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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 50(10): 1000-1006, 2022 Oct 24.
Artículo en Zh | MEDLINE | ID: mdl-36299223

RESUMEN

Objective: To explore the association between genetic variants of matrix metalloproteinase enzyme 2 (MMP2) gene and the blood pressure of children and adolescents. Methods: This cross-sectional study was performed in 2016 and included 4 155 children and adolescents in the urban area of Guangzhou. Physical examinations (including body height, weight, and blood pressure), questionnaires (including general characteristics, physical exercise, parental educational level, household income, etc.), and blood sampling were performed. Multivariable linear regression models were used to investigate the associations of MMP2 genetic variations (rs243865, rs7201) and the genetic risk score (GRS) level with standardized blood pressure. Mediating effect of standardized body mass index (BMI) was further assessed by process analysis in the association between GRS level and blood pressure, and potential additive interaction between physical activity and GRS level was analyzed using the product term in the regression model. Results: A total of 4 155 primary and secondary schoolchildren were finally included in the analysis, consisting of 1 401 (33.7%) second grade pupils of primary school, 1 422 (34.2%) first grade pupils of middle school, and 1 332 (32.1%) first-grade students of senior high school. After adjusting for age, sex, parental educational level, and family income, as compared to the rs243865 TT genotype, the CC/CT genotype increased diastolic blood pressure (DBP) by 0.461 standard deviations (SD) (ß for dominant model=0.461, 95%CI 0.199-0.723). When compared to the rs7201 CC genotype, the AA/AC genotype showed 0.147 SD higher systolic blood pressure (SBP) (ß for recessive model=0.147, 95%CI 0.014-0.279) and 0.171 SD increased DBP (ß for recessive model=0.171, 95%CI 0.039-0.304). For each increment of GRS level, SBP and DBP increased by 0.151 SD (ß for dominant model=0.151, 95%CI 0.029-0.272) and 0.242 SD (ß=0.242, 95%CI 0.120-0.363), respectively. The mediating effect of BMI accounted for 28.3% and 12.6% of the total effect of GRS on SBP and DBP, respectively. After controlling BMI, the direct effect of GRS on DBP remained statistically significant (P<0.001). The insufficient moderate-to-vigorous physical activity (<0.5 h/d) showed a significant interaction with GRS on SBP under additive scale (ß for interaction=0.518, 95%CI 0.088-0.949, P=0.018). Conclusions: rs243865 and rs7201 variants in MMP2 gene are associated with the elevated blood pressure of children and adolescents. Obesity may yield a mediation role in the associations, while insufficient physical activity may have a positively additive interaction with MMP2 genetic variants.


Asunto(s)
Presión Sanguínea , Hipertensión , Metaloproteinasa 2 de la Matriz , Adolescente , Niño , Humanos , Presión Sanguínea/genética , Índice de Masa Corporal , Estudios Transversales , Hipertensión/complicaciones , Hipertensión/genética , Metaloproteinasa 2 de la Matriz/genética , Obesidad Infantil/complicaciones , Obesidad Infantil/genética , Ejercicio Físico/genética
2.
Gastroenterology ; 155(3): 687-695.e10, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29857091

RESUMEN

BACKGROUND & AIMS: As more treatment options for inflammatory bowel diseases become available, it is important to identify patients most likely to respond to different therapies. We created and validated a scoring system to identify patients with Crohn's disease (CD) who respond to vedolizumab. METHODS: We collected data from the GEMINI 2 phase 3 trial of patients with active CD treated with vedolizumab for 26 weeks (n = 814) and performed logistic regression analysis to identify factors associated with clinical, steroid-free, and durable remission (derivation set). We used these data to develop a clinical decision support tool, which we validated using data from 366 participants in a separate clinical practice observational cohort of patients with active CD treated with vedolizumab for 26 weeks (the VICTORY cohort). We evaluated the ability of this tool to identify patients in clinical remission or corticosteroid-free remission, or those with mucosal healing (MH), clinical remission with MH, or corticosteroid-free remission with MH after vedolizumab therapy using receiver operating characteristic area under the curve (AUC) analyses. The primary outcome was to develop and validate a list of factors associated with achieving remission by vedolizumab in patients with active CD. RESULTS: In the derivation analysis, we identified absence of previous treatment with a tumor necrosis factor antagonist (+3 points), absence of prior bowel surgery (+2 points), absence of prior fistulizing disease (+2 points), baseline level of albumin (+0.4 points per g/L), and baseline concentration of C-reactive protein (reduction of 0.5 points for values between 3.0 and 10.0 mg/L and 3.0 points for values >10.0 mg/L) as factors associated with remission. In the validation set, our model identified patients in clinical remission with an AUC of 0.67, patients in corticosteroid-free remission with an AUC of 0.66, patients with MH with an AUC of 0.72, patients in clinical remission with MH with an AUC of 0.73, and patients in corticosteroid-free clinical remission with MH with an AUC of 0.75. A cutoff value of 13 points identified patients in clinical remission after vedolizumab therapy with 92% sensitivity, patients in corticosteroid-free remission with 94% sensitivity, patients with MH with 98% sensitivity, patients with clinical remission and MH with 100% sensitivity, and patients with corticosteroid-free clinical remission with MH with 100% sensitivity. CONCLUSIONS: We developed and validated a scoring system to identify patients with CD most likely to respond to 26 weeks of vedolizumab therapy. Further studies are needed to optimize its accuracy in select populations and determine its cost-effectiveness.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Enfermedad de Crohn/tratamiento farmacológico , Fármacos Gastrointestinales/administración & dosificación , Quimioterapia de Inducción/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Adulto , Área Bajo la Curva , Proteína C-Reactiva/análisis , Femenino , Humanos , Quimioterapia de Inducción/métodos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Resultado del Tratamiento
3.
J Intern Med ; 286(6): 644-650, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31077464

RESUMEN

BACKGROUND: Severe hypertriglyceridemia (serum triglyceride >10 mmol L-1 ) is implicated in ~9% of acute pancreatitis cases. Certain guidelines list severe hypertriglyceridemia as an indication for plasmapheresis. OBJECTIVE: We assembled the natural trajectory of triglyceride levels in patients with acute pancreatitis due to severe hypertriglyceridemia who were managed conservatively without plasmapheresis to evaluate the effectiveness of this approach. METHODS: A retrospective chart review was performed on 22 hospital admissions for acute pancreatitis episodes considered to be caused by severe hypertriglyceridemia. Patients were managed supportively, with cessation of oral intake (NPO) and intravenous hydration. Insulin infusion was used in 12 patients to manage concurrent hyperglycaemia. RESULTS: Triglyceride levels for the group were evaluated using a mixed-effects model. The average triglyceride level fell from 45.4 mmol L-1 on presentation to 13.3 mmol L-1 within 48 h, corresponding to a mean 69.8% decrease. Regression analysis showed a triglyceride half-life of 30.6 h. Findings were similar for NPO-only and insulin infusion subgroups. CONCLUSION: Patients with severe hypertriglyceridemia and acute pancreatitis can be conservatively managed safely and effectively without plasmapheresis.


Asunto(s)
Tratamiento Conservador , Hipertrigliceridemia/complicaciones , Hipertrigliceridemia/terapia , Pancreatitis/etiología , Pancreatitis/terapia , Enfermedad Aguda , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Eur J Neurol ; 26(4): 651-659, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30565793

RESUMEN

BACKGROUND AND PURPOSE: Cognitive enhancers are commonly prescribed to people with Alzheimer's disease and related dementias to improve cognition and function. However, their effectiveness for individuals in the pre-stages of dementia, particularly in functional motor outcomes, remains unknown. We aimed to determine the efficacy of donepezil, a cognitive enhancer that improves cholinergic neurotransmission, on gait performance in mild cognitive impairment (MCI). METHODS: This was a double-blind, placebo-controlled trial including 60 older adults with MCI, randomized to receive donepezil (10 mg/daily, maximal dose) or placebo. Primary outcome was gait speed (cm/s) under single and three dual-task conditions (counting backwards by 1 or 7 and naming animals) measured using an electronic walkway. Dual-task gait cost (DTC), a valid measure of motor-cognitive interaction, was calculated as the percentage change between single (S) and dual-task (D) gait speeds: [(S - D)/S] × 100. Secondary outcomes included attention, executive function, balance and falls. RESULTS: After 6 months, the donepezil group experienced an improvement in dual-task gait speed (range 4-11 cm/s), although this was not statistically significant. The donepezil group showed a significant reduction in DTC (improvement) by counting backwards by 1 and 7 compared with placebo (10.25% vs. 1.75%, P = 0.048; 21.38% vs. 14.64%, P = 0.037, intention-to-treat analysis). Per-protocol analyses showed that all three DTCs improved in the donepezil group, along with a non-significant reduction of rate of falls. CONCLUSIONS: Donepezil treatment improved dual-task gait speed and DTC in elderly patients with MCI. Our results support the concept of reducing falls in MCI by targeting the motor-cognitive interface.


Asunto(s)
Accidentes por Caídas/prevención & control , Disfunción Cognitiva/tratamiento farmacológico , Donepezilo/uso terapéutico , Marcha/efectos de los fármacos , Nootrópicos/uso terapéutico , Anciano , Anciano de 80 o más Años , Cognición/efectos de los fármacos , Disfunción Cognitiva/fisiopatología , Donepezilo/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Masculino , Nootrópicos/administración & dosificación
5.
BMC Public Health ; 19(1): 841, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31253112

RESUMEN

BACKGROUND: Our objective was to determine the influence of the HealtheSteps™ lifestyle prescription program on physical activity and modifiable risk factors for chronic disease in individuals at risk. METHODS: One hundred eighteen participants were recruited from 5 sites in Southwestern Ontario, Canada and randomized to either the intervention (HealtheSteps™ program, n = 59) or a wait-list control group (n = 59). The study comprised three phases: an Active Phase (0 to 6 months) consisted of bi-monthly in-person lifestyle coaching with access to a suite of eHealth technology supports (Heathesteps app, telephone coaching and a private HealtheSteps™ social network) followed by a Minimally-Supported Phase I (6 to 12 months), in which in-person coaching was removed, but participants still had access to the full suite of eHealth technology supports. In the final stage, Minimally-Supported Phase II (12 to 18 months), access to the eHealth technology supports was restricted to the HealtheSteps™ app. Assessments were conducted at baseline, 6, 12 and 18 months. The study primary outcome was the 6-month change in average number of steps per day. Secondary outcomes included: self-reported physical activity and sedentary time; self-reported eating habits; weight and body composition measures; blood pressure and health-related quality of life. Data from all participants were analyzed using an intent-to-treat approach. We applied mixed effects models for repeated measurements and adjusted for age, sex, and site in the statistical analyses. RESULTS: Participants in HealtheSteps™ increased step counts (between-group [95% confidence interval]: 3132 [1969 to 4294], p < 0.001), decreased their sitting time (- 0.08 [- 0.16 to - 0.006], p = 0.03), and improved their overall healthful eating (- 1.5 [- 2.42 to - 0.58], p = 0.002) to a greater extent compared to control at 6 months. Furthermore, exploratory results showed that these individuals maintained these outcomes 12 months later, after a minimally-supported phase; and retained improvements in sedentary time and improved healthful eating after 18 months. No differences in self-reported physical activity, health-related quality of life, weight, waist circumference or blood pressure were observed between groups at 6 months. CONCLUSIONS: Our findings suggest that HealtheSteps™ is effective at increasing physical activity (i.e., step counts per day), decreasing weekday sitting time, and improving healthful eating in adults at increased risk for chronic disease after 6 months; however, we did not see change in other risk factors. Nonetheless, the maintenance of these behaviours with minimal support after 12 and even 18 months indicates the promise of HealtheSteps™ for long-term sustainability. TRIAL REGISTRATION: The trial was registered on April 6, 2015 with ClinicalTrials.gov (identifier: NCT02413385 ).


Asunto(s)
Enfermedad Crónica/prevención & control , Ejercicio Físico/psicología , Promoción de la Salud/métodos , Estilo de Vida Saludable , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Ontario , Evaluación de Programas y Proyectos de Salud , Factores de Riesgo , Autoinforme
6.
Cochrane Database Syst Rev ; 1: CD011450, 2018 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-29338066

RESUMEN

BACKGROUND: Endoscopic assessment of mucosal disease activity is routinely used to determine eligibility and response to therapy in clinical trials of ulcerative colitis. The operating properties of the existing endoscopic scoring indices are unclear. OBJECTIVES: A systematic review was undertaken to evaluate the development and operating characteristics of endoscopic scoring indices for the evaluation of ulcerative colitis. SEARCH METHODS: We searched MEDLINE, Embase and CENTRAL from inception to 5 July 2016. We also searched references and conference proceedings (Digestive Disease Week, United European Gastroenterology Week, European Crohn's and Colitis Organization). SELECTION CRITERIA: Any study design (e.g. randomized controlled trials, cohort studies, case series) that evaluated endoscopic indices for evaluation of ulcerative colitis disease activity were considered for inclusion. Eligible participants were adult patients (> 16 years), diagnosed with ulcerative colitis using conventional clinical, radiologic and endoscopic criteria. DATA COLLECTION AND ANALYSIS: Two authors independently reviewed the studies identified from the literature search. These authors also independently extracted and recorded data on the number of patients enrolled; number of patients per treatment arm; patient characteristics including age and gender distribution; endoscopic index; and outcomes such as reliability (intra-rater and inter-rater), validity (content, construct, criterion), responsiveness and feasibility. Any disagreements regarding study inclusion or data extraction were resolved by discussion and consensus with a third author. Risk of bias was assessed by determining whether assessors were blinded to clinical information and whether assessors scored the endoscopic index independently. We also assessed the methodological quality of the validation studies using the COSMIN checklist MAIN RESULTS: A total of 23 reports of 20 studies met the pre-defined inclusion criteria and were included in the review. Of the 20 included validation studies, 19 endoscopic scoring indices were assessed, including the Azzolini Classification, Baron Score, Blackstone Endoscopic Interpretation, Chinese Grading System of Ulcerative Colitis, Endoscopic Activty Index, Jeroen Score, Magnifying Colonoscopy Grade, Matts Score, Mayo Clinic Endoscopic Subscore, Modified Baron Score, Modified Mayo Clinic Endoscopic Subscore, Osada Score, Rachmilewtiz Endoscopic Score, St. Mark's Index, Ulcerative Colitis Colonoscopic Index of Serverity (UCCIS), endoscopic component of the Ulcerative Colitis Disease Activity Index (UCDAI), Ulcerative Colitis Endoscopic Index of Severity (UCEIS), Witts Sigmoidoscopic Score and Watson Grade. The individuals who performed the endoscopic scoring were blinded to clinical and/or histologic information in ten of the included studies, not blinded to clinical and/or histologic information in one of the included studies, and it was unclear whether blinding occurred in the remaining nine included studies. Independent observation was confirmed in four of the included studies, unclear in five of the included studies, and non-applicable (since inter-rater reliability was not assessed) in the remaining eleven included studies. The methodological quality (COSMIN checklist) of most of the included studies was rated as 'good' or 'excellent'. One study that assessed responsiveness was rated as 'fair'. The inter-rater reliability of nine endoscopic scoring indices including the Baron Score, Blackstone Endoscopic Interpretation, Endoscopic Activity Index, Matts Score, Mayo Clinic Endoscopic Subscore, Osada Score, UCCIS, UCEIS, Watson Grade was assessed in seven studies, with estimates of correlation, ƙ, ranging from 0.44 to 0.97. The iIntra-rater reliability of seven endoscopic scoring indices including the Baron Score, Blackstone Endoscopic Interpretation, Matts Score, Mayo Clinic Endoscopic Subscore, Osada Score, UCCIS and UCEIS was assessed in three studies, with estimates of correlation, ƙ, ranging from 0.41 to 0.86. No studies assessed content validity. Three studies evaluated the criterion validity of three endoscopic scoring indices including the Rachmilewitz Endoscopic Score, Magnifying Colonoscopy Grade and the UCCIS. These indices were correlated with objective markers of disease activity including albumin, blood leukocytes, C-reactive protein, fecal calprotectin, hemoglobin, mucosal interleukin-8 concentration and platelet count. Correlation estimates ranged from r = -0.19 to 0.83. Thirteen endoscopic scoring indices were tested for construct validity in 13 studies. Estimates of correlation between the endoscopic scoring indices and other measures of disease activity ranged from r = 0.27 to 0.93. Two studies explored the responsiveness of four endoscopic scoring indices including the Mayo Endoscopic Subscore, Modified Baron Score, Modified Mayo Endoscopic Subscore and UCEIS. One study concluded that the Modified Baron Score, Modified Mayo Endoscopic Subscore and UCEIS had similar responsiveness for detecting disease change in ulcerative colitis. The other included study concluded that the UCEIS may be the most accurate endoscopic scoring tool. None of the included studies formally assessed feasibility. AUTHORS' CONCLUSIONS: While the UCEIS, UCCIS and Mayo Clinic Endoscopic Subscore have undergone extensive validation, none of these instruments have been fully validated and only two studies assessed responsiveness. Further research on the operating properties of these indices is needed given the lack of a fully-validated endoscopic scoring instrument for the evaluation of disease activity in ulcerative colitis.


Asunto(s)
Colitis Ulcerosa/diagnóstico , Colonoscopía , Colitis Ulcerosa/patología , Humanos , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Sigmoidoscopía
7.
BMC Geriatr ; 18(1): 93, 2018 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-29661156

RESUMEN

BACKGROUND: Physical exercise, cognitive training, and vitamin D are low cost interventions that have the potential to enhance cognitive function and mobility in older adults, especially in pre-dementia states such as Mild Cognitive Impairment (MCI). Aerobic and progressive resistance exercises have benefits to cognitive performance, though evidence is somewhat inconsistent. We postulate that combined aerobic exercise (AE) and progressive resistance training (RT) (combined exercise) will have a better effect on cognition than a balance and toning control (BAT) intervention in older adults with MCI. We also expect that adding cognitive training and vitamin D supplementation to the combined exercise, as a multimodal intervention, will have synergistic efficacy. METHODS: The SYNERGIC trial (SYNchronizing Exercises, Remedies in GaIt and Cognition) is a multi-site, double-blinded, five-arm, controlled trial that assesses the potential synergic effect of combined AE and RT on cognition and mobility, with and without cognitive training and vitamin D supplementation in older adults with MCI. Two-hundred participants with MCI aged 60 to 85 years old will be randomized to one of five arms, four of which include combined exercise plus combinations of dual-task cognitive training (real vs. sham) and vitamin D supplementation (3 × 10,000 IU/wk. vs. placebo) in a quasi-factorial design, and one arm which receives all control interventions. The primary outcome measure is the ADAS-Cog (13 and plus modalities) measured at baseline and at 6 months of follow-up. Secondary outcomes include neuroimaging, neuro-cognitive performance, gait and mobility performance, and serum biomarkers of inflammation (C reactive protein and interleukin 6), neuroplasticity (brain-derived neurotropic factor), endothelial markers (vascular endothelial growth factor 1), and vitamin D serum levels. DISCUSSION: The SYNERGIC Trial will establish the efficacy and feasibility of a multimodal intervention to improve cognitive performance and mobility outcomes in MCI. These interventions may contribute to new approaches to stabilize and reverse cognitive-mobility decline in older individuals with MCI. TRIAL REGISTRATION: Identifier: NCT02808676. https://www.clinicaltrials.gov/ct2/show/NCT02808676 .


Asunto(s)
Cognición/fisiología , Disfunción Cognitiva/rehabilitación , Suplementos Dietéticos , Terapia por Ejercicio/métodos , Tolerancia al Ejercicio/fisiología , Marcha/fisiología , Entrenamiento de Fuerza/métodos , Anciano , Anciano de 80 o más Años , Disfunción Cognitiva/psicología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
8.
Gastrointest Endosc ; 86(6): 1079-1087, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28760533

RESUMEN

BACKGROUND AND AIMS: EUS is a potentially useful modality to assess severity of inflammation in ulcerative colitis (UC). We assessed the reliability of existing EUS indices and correlated them with endoscopic and histologic scores. METHODS: Four blinded endosonographers assessed 58 endoscopic and EUS videos in triplicate, from patients with UC. Intrarater and interrater reliability of the hyperemia and Tsuga scores were estimated by using intra-class correlation coefficients (ICCs). Correlation with the Mayo endoscopy score, modified Baron score (MBS), Ulcerative Colitis Endoscopic Index of Severity (UCEIS), and Geboes histopathology score (GHS) were calculated by using bootstrapping methods. A RAND consensus process led to development of standardized definitions and a revised EUS-UC score. RESULTS: ICCs for intrarater reliability were 0.76 (95% confidence interval [CI], 0.71-0.80) for the hyperemia score and 0.85 (95% CI, 0.79-0.89) for the Tsuga score. Corresponding values for interrater reliability were 0.34 (95% CI, 0.25-0.42) and 0.36 (95% CI, 0.24-0.46). Correlation between hyperemia and Tsuga scores to Mayo scoring system, MBS, UCEIS, and the GHS were 0.39 (95% CI, 0.15-0.61) and 0.28 (95% CI, 0.04-0.51), 0.38 (95% CI, 0.16-0.57) and 0.25 (95% CI, -0.01-0.48), 0.41 (95% CI, 0.16-0.62) and 0.27 (95% CI, 0.01-0.50), 0.37 (95% CI, -0.01-0.48) and 0.24 (95% CI, 0.13-0.57), respectively. The revised EUS-UC score included bowel wall thickening, depth of inflammation, and hyperemia. CONCLUSIONS: Although substantial to almost perfect intrarater agreement existed for EUS indices in UC, interrater agreement was fair. Standardization of item definitions with development of a revised evaluative instrument has potential application as an evaluative and prognostic tool for UC. (Clinical trial registration number: NCT01852760.).


Asunto(s)
Colitis Ulcerosa/diagnóstico por imagen , Colitis Ulcerosa/patología , Endosonografía , Adulto , Anciano , Anciano de 80 o más Años , Colonoscopía , Femenino , Humanos , Hiperemia/diagnóstico por imagen , Inflamación/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Método Simple Ciego , Grabación en Video , Adulto Joven
9.
Cochrane Database Syst Rev ; 5: CD011256, 2017 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-28542712

RESUMEN

BACKGROUND: Disease activity can be determined using clinical, endoscopic or histologic criteria in patients with ulcerative colitis (UC). Persistent disease activity is associated with poor outcomes. Histologic disease activity has been shown to be associated with relapse, colectomy and colorectal cancer. The ability to objectively evaluate microscopic disease activity using histology is important for both clinical practice and clinical trials. However, the operating properties of the currently available histologic indices remain unclear. OBJECTIVES: A systematic review was undertaken to identify and evaluate the development and operating characteristics of histologic disease activity indices used to assess disease activity in people with ulcerative colitis. SEARCH METHODS: We searched MEDLINE, EMBASE, PubMed, CENTRAL and the Cochrane IBD Review Group Specialized Trials Register from inception to 2 December 2016 for applicable studies. There were no language or document type restrictions. SELECTION CRITERIA: Any study design (e.g. randomized controlled trials, cohort studies, case series) that evaluated a histologic index in patients with UC were considered for inclusion. Eligible patients were adults (> 18 years), diagnosed with UC using conventional clinical, radiographic, endoscopic and histologic criteria. DATA COLLECTION AND ANALYSIS: Two authors (MHM and CEP) independently reviewed the titles and abstracts of the studies identified from the literature search. A standardized form was used to assess eligibility of trials for inclusion and for data extraction.Two authors (MHM and CEP) independently extracted and recorded data, which included the number of patients enrolled, number of patients per treatment arm, patient characteristics including age and gender distribution, and the name of the histologic index. Outcomes (i.e. intra-rater reliability, inter-rater reliability, internal consistency, content validity, criterion validity, construct validity, responsiveness, and feasibility) were recorded for each trial. MAIN RESULTS: In total, 126 reports describing 30 scoring indices were identified through the screening process. Eleven of the 30 scoring indices have undergone some form of index validation. Intra-rater reliability was assessed for eight scoring indices. Inter-rater reliability was evaluated for all 11 of the scoring indices. Three of the indices underwent content validation. Two of the included scoring indices assessed criterion validity. Six of the included scoring indices explored content validity. Two of the included scoring indices were tested for responsiveness. AUTHORS' CONCLUSIONS: The Nancy Index and the Robarts Histopathology Index have undergone the most validation in that four operating properties including reliability, content validity, construct validity (hypothesis testing) and criterion validity have been tested. However, none of the currently available histologic scoring indices have been fully validated. In order to determine the optimal endpoint for histologic healing in UC, more research is required. The optimal index would need to be fully validated.


Asunto(s)
Colitis Ulcerosa/patología , Índice de Severidad de la Enfermedad , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Heces/química , Humanos , Lactoferrina/análisis , Recuento de Leucocitos , Complejo de Antígeno L1 de Leucocito/análisis , Variaciones Dependientes del Observador , Elastasa Pancreática/análisis , Reproducibilidad de los Resultados
10.
Cochrane Database Syst Rev ; 9: CD011572, 2017 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-28886205

RESUMEN

BACKGROUND: It is important to minimize placebo rates in randomised controlled trials (RCTs) to efficiently detect treatment differences between interventions. Historically, high placebo rates have been observed in clinical trials of ulcerative colitis (UC). A better understanding of factors influencing placebo rates may lead to more informed clinical trial design. OBJECTIVES: A systematic review and meta-analysis was conducted to evaluate placebo response and remission rates in RCTs evaluating UC treatments in adult patients. SEARCH METHODS: Electronic databases (i.e. MEDLINE, EMBASE, and CENTRAL) were searched from inception to 1 March 2017 with no language restrictions applied. Reference lists and conference proceedings of major gastroenterology meetings were also handsearched to identify additional studies. SELECTION CRITERIA: Placebo-controlled RCTs of adult patients with UC treated with corticosteroids, aminosalicylates, immunosuppressives or biologics were eligible, provided enrolment and outcome assessment was conducted using the Ulcerative Colitis Disease Activity Index (UCDAI) or the Mayo Clinic Score. The minimum trial duration was two weeks for induction trials and four months maintenance trials. DATA COLLECTION AND ANALYSIS: Pairs of authors independently determined study eligibility and extracted data with any disagreements resolved through consensus. Outcomes of interest included the proportion of patients with clinical response and remission. Trial characteristics such as the design, participant demographics and disease history, interventions, and enrolment and assessment criteria were also recorded. The methodological quality of the included studies was evaluated using the Cochrane risk of bias tool. Pooled placebo response and remission rates and 95% confidence intervals (95% CI) were calculated using a binomial normal model for proportions. Induction of remission and maintenance studies were pooled separately. The impact of study-level characteristics on placebo response and remission rates was investigated using mixed-effects meta-regression analyses with logits of event rates as the outcome variables. An assessment of pooled placebo rates over time was conducted using a cumulative meta-analysis based on date of publication. Publication bias was examined using funnel plots. MAIN RESULTS: The screening process identified 61 included studies which encompass 58 induction phases (5111 patients randomised to placebo) and 12 maintenance phases (1579 patients randomised to placebo). For induction trials, the pooled estimate of placebo response was 33% (95% CI 30% to 36%) while the pooled estimate of placebo remission was 12% (95% CI 9% to 15%). For maintenance trials, the pooled estimate of placebo response was 23% (95% CI 19% to 28%) while the pooled estimate of placebo remission was 17% (95% CI 10% to 27%).Studies enrolling patients with more active disease confirmed objectively by endoscopy were associated with significantly lower placebo remission and response rates than trials enrolling patients with less active disease (27% versus 4%, OR 2.60, 95% CI 1.25 to 5.42, P = 0.01 for UCDAI endoscopy sub score ≥1 versus ≥ 2 for remission; and 27% versus 4%, OR 1.70, 95% CI 1.02 to 2.82, P = 0.02 for UCDAI endoscopy sub score greater than or equal to one versus greater than or equal to two for response). With respect to drug class, the lowest placebo response and remission rates were observed in trials evaluating corticosteroids (23%; 95% CI 19 to 29%, and 5%; 95% CI 2 to 11%, respectively). Trials of biologics had the highest placebo response rate (35%; 95% CI 30 to 41%), while trials evaluating aminosalicylates had the highest placebo remission rate (18%; 95% CI 12 to 24%). Disease duration of greater than five years prior to enrolment was associated with a significantly lower placebo response rate compared to disease duration of less than or equal to five years (29% versus 47%, respectively; OR 0.54, 95% CI 0.32 to 0.92, P = 0.02). The requirement of a minimum rectal bleeding score for study eligibility was associated with an increased placebo response rate compared to studies that did not use rectal bleeding for trial eligibility (37% versus 32%, respectively; OR 1.70, 95% CI 1.02 to 2.82, P = 0.02). Finally, the time point of primary outcome assessment was found to be significantly associated with placebo remission rates such that every one week increment in endpoint assessment was associated with a 6% increase in the placebo remission rate (OR 1.06, 95% CI 1.02 to 1.10, P = 0.01).Cumulative meta-analysis indicated a consistent increase in the placebo response rate from 1987 to 2007 (from 13% to 33%), although rates have remained constant from 2008 to 2015 (32% to 34%). Similarly, placebo remission rates increased from 1987 to 2007 (5% to 14%) but have remained constant from 2008 to 2015 (12 to 14%). On meta-regression, there were no statistically significant differences between the 1987-2007 and 2008-2015 point estimates for both response (P = 0.81) and remission (P = 0.32). AUTHORS' CONCLUSIONS: Placebo response and remission rates vary according to endoscopic disease severity and rectal bleeding score at trial entry, class of agent, disease duration, and the time point at which the primary outcome was measured. These observations have important implications for the design and conduct of future clinical trials in UC and will help researchers design trials, determine required sample sizes and also provide useful information about trial design features which should be considered when planning new trials.


Asunto(s)
Ácidos Aminosalicílicos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Productos Biológicos/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Quimioterapia de Inducción , Quimioterapia de Mantención , Adulto , Hemorragia Gastrointestinal/complicaciones , Hemorragia Gastrointestinal/diagnóstico , Humanos , Quimioterapia de Inducción/estadística & datos numéricos , Quimioterapia de Mantención/estadística & datos numéricos , Efecto Placebo , Ensayos Clínicos Controlados Aleatorios como Asunto , Recto
11.
Cochrane Database Syst Rev ; (8): CD010642, 2016 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-27501379

RESUMEN

BACKGROUND: Endoscopic assessment of mucosal disease activity is widely used to determine eligibility and response to therapy in clinical trials of treatment for Crohn's disease. However, the operating properties of the currently available endoscopic indices remain unclear. OBJECTIVES: A systematic review was undertaken to evaluate the development and operating characteristics of the Crohn's Disease Endoscopic Index of Severity (CDEIS) and Simple Endoscopic Scale for Crohn's Disease (SES-CD). SEARCH METHODS: Electronic searches of the MEDLINE (1966 to December 2015), EMBASE (1980 to December 2015), and Cochrane CENTRAL Register of Controlled Trials (Issue 12, 2015) databases were supplemented by manual reviews of reference listings and conference proceedings (Digestive Disease Week, United European Gastroenterology Week, European Crohn's and Colitis Organization). SELECTION CRITERIA: Any study design (e.g. randomized controlled trials, cohort studies, case series) that evaluated either or both the CDEIS or SES-CD in patients with Crohn's disease was considered for inclusion. Eligible participants were adult patients (> 16 years), diagnosed with Crohn's disease using conventional clinical, radiographic, and endoscopic criteria. DATA COLLECTION AND ANALYSIS: Two authors (RK, JKM) independently reviewed the titles and abstracts of the studies identified from the literature search. The full texts of potentially relevant citations were reviewed for inclusion and the study investigators were contacted to clarify any unclear data. Any disagreements were resolved by discussion and consensus with a third author. A standardized form was used to assess eligibility of trials for inclusion in the study and for data extraction.Two authors independently extracted and recorded data (RK, SAN). The number of patients enrolled; number of patients per treatment arm; patient characteristics including age and gender distribution; endoscopic index; and outcomes such as intra-rater reliability, inter-rater reliability responsiveness, validity, feasibility, construct validity, and criterion validity were recorded for each trial. MAIN RESULTS: Forty-three reports of 30 studies fulfilled the inclusion criteria.For the SES-CD, inter-rater reliability was assessed in four studies. In the development study for the SES-CD (Daperno 2004), the overall ICC (0.9815, 95% CI 0.9705 to 0.9884) and the kappa for the regions is high; however the paired raters were in the same room which introduces the potential for bias.For the CDEIS, inter-rater reliability was assessed in six studies. Daperno 2014 reported that the ICC for the CDEIS was 0.985 (95% CI 0.939-1.000) for average measures of video score and was 0.835 (95% CI 0.540-0.995) for single measures of video score.With respect to validity, correlation between the CDEIS and clinical measures, including C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), was also reported. The estimates of correlation with CRP were r = 0.521 (Sipponen 2010b), r = 0.553 (Sipponen 2008a) and r = 0.608 (Sipponen 2008c). For the SES-CD, the corresponding values for correlation with CRP ranged from r = 0.46 (Jones 2008) to r = 0.68 (Green 2011).Responsiveness data for the CDEIS were available in nine studies. Seven studies demonstrated statistically significant decreases in the CDEIS score after administration of a treatment of known efficacy. Minimal responsiveness data were available for the SES-CD. Sipponen 2010a and Sipponen 2010b demonstrated statistically significant changes in the SES-CD score after subjects were administered a treatment of known efficacy.No studies were identified that explicitly evaluated the feasibility for either the SES-CD or the CDEIS. The SES-CD requires fewer calculations and may therefore be easier to use than the CDEIS. AUTHORS' CONCLUSIONS: Although they are used in clinical trials, the CDEIS and SES-CD remain incompletely validated. Future research is required to determine the operating properties and to define the optimal index.


Asunto(s)
Enfermedad de Crohn/patología , Endoscopía Gastrointestinal , Índice de Severidad de la Enfermedad , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Estudios de Cohortes , Heces/química , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados
12.
Gut ; 64(10): 1539-45, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25336114

RESUMEN

OBJECTIVE: Although low infliximab trough concentrations and antibodies to infliximab (ATI) are associated with poor outcomes in patients with Crohn's disease (CD), the clinical relevance of ATI in patients with adequate infliximab concentrations is uncertain. We evaluated this question using an assay sensitive for identification of ATI in the presence of infliximab. DESIGN: In an observational study, 1487 trough serum samples from 483 patients with CD who participated in four clinical studies of maintenance infliximab therapy were analysed using a fluid phase mobility shift assay. Infliximab and ATI concentrations most discriminant for remission, defined as a C-reactive protein concentration of ≤ 5 mg/L, were determined by receiver operating characteristic curves. A multivariable regression model evaluated these factors as independent predictors of remission. RESULTS: Based upon analysis of 1487 samples, 77.1% of patients had detectable and 22.9% had undetectable infliximab concentrations, of which 9.5% and 71.8%, respectively, were positive for ATI. An infliximab concentration of > 2.79 µg/mL (area under the curve (AUC) = 0.681; 95% CI 0.632 to 0.731) and ATI concentration of < 3.15 U/mL (AUC = 0.632; 95% CI 0.589 to 0.676) were associated with remission. Multivariable analysis showed that concentrations of both infliximab trough (OR 1.8; 95% CI 1.3 to 2.5; p < 0.001) and ATI (OR 0.57; 95% CI 0.39 to 0.81; p = 0.002) were independent predictors of remission. CONCLUSIONS: The development of ATI increases the probability of active disease even at low concentrations and in the presence of a therapeutic concentration of drug during infliximab maintenance therapy. Evaluation of strategies to prevent ATI formation, including therapeutic drug monitoring with selective infliximab dose intensification, is needed.


Asunto(s)
Anticuerpos Monoclonales/sangre , Enfermedad de Crohn/tratamiento farmacológico , Infliximab/administración & dosificación , Adulto , Biomarcadores/sangre , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/inmunología , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/inmunología , Fármacos Gastrointestinales/farmacocinética , Humanos , Infliximab/inmunología , Infliximab/farmacocinética , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Inducción de Remisión , Índice de Severidad de la Enfermedad
13.
Dig Dis Sci ; 59(4): 838-49, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24323180

RESUMEN

BACKGROUND: Computed tomography (CT) and magnetic resonance (MR) enterography are now widely used to diagnose and monitor Crohn's disease. AIM: We sought to assess the use of enterography for management of inflammatory bowel disease (IBD) in our medical center. METHODS: We performed a retrospective review of all patients diagnosed with IBD who underwent MR or CT enterography from November 1, 2010 to October 25, 2012 at our institution. We assessed disease complications identified by enterography, agreement between disease activity determined by endoscopy and enterography, association between inflammatory markers and enterography-determined disease activity and recommended changes in medical and surgical management following enterography. RESULTS: A total of 311 enterography studies (291 MR and 20 CT enterographies) were performed on 270 patients, including 258 (83.0 %) on patients with presumed Crohn's disease and 53 (17.0 %) with presumed ulcerative colitis. Active small bowel (SB) disease was noted in 73/311 (23.5 %) studies. Complications including strictures, perianal fistulas, abscesses and SB fistulas were noted in 108/311 (34.7 %) studies. Endoscopic and enterography defined active disease had an agreement of κ = 0.36 in the ileum (n = 179). A total of 142/311 (45.7 %) enterographies were associated with recommended medication changes within 90 days while surgery or endoscopic dilation of stricture was recommended following 41/311 (13.2 %) enterographies. Enterography resulted in a change in diagnosis from ulcerative colitis to Crohn's in 5/311 (1.6 %) studies. CONCLUSION: Enterography reveals active disease and complications not evident on endoscopy and should be considered in the initial diagnosis, assessment of disease activity, and monitoring of therapy in patients with IBD.


Asunto(s)
Enfermedades Inflamatorias del Intestino/diagnóstico , Intestino Delgado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X , Adulto , Endoscopía del Sistema Digestivo , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos
14.
J Prev Alzheimers Dis ; 11(5): 1490-1499, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39350396

RESUMEN

BACKGROUND: It has been suggested that up to 40% of dementia cases worldwide are associated with modifiable risk factors; however, these estimates are not known in Canada. Furthermore, sleep disturbances, an emerging factor, has not been incorporated into the life-course model of dementia prevention. OBJECTIVE: To estimate the population impact of 12 modifiable risk factors in Canadian adults including sleep disturbances, by sex and age groups, and to compare with other countries. DESIGN: Cross-sectional analysis of Canadian Longitudinal Study on Aging baseline data. SETTING: Community. PARTICIPANTS: 30,097 adults aged 45 years and older. MEASUREMMENTS: Prevalence and Population Attributable Fractions (PAFs) associated with less education, hearing loss, traumatic brain injury, hypertension, excessive alcohol, obesity, smoking, depression, social isolation, physical inactivity, diabetes, and sleep disturbances. RESULTS: The risk factors with the largest PAF were later life physical inactivity (10.2%; 95% CI, 6.8% to 13%), midlife hearing loss (6.5%; 3.7% to 9.3%), midlife obesity (6.4%; 4.1% to 7.7%), and midlife hypertension (6.2%; 2.7% to 9.3%). The PAF of later life sleep disturbances was 3.0% (95% CI, 1.8% to 3.8%). The 12 risk factors accounted for 51.9% (32.2% to 68.0%) of dementia among men and 52.4% (32.5% to 68.7%) among women. Overall, the combined PAF of all risk factors was 49.2% (31.1% to 64.9%), and it increased with age. CONCLUSION: Nearly up to 50% of dementia cases in Canada are attributable to 12 modifiable risk factors across the lifespan. Canadian risk reduction strategies should prioritize targeting physical inactivity, hearing loss, obesity, and hypertension.


Asunto(s)
Demencia , Humanos , Canadá/epidemiología , Masculino , Femenino , Demencia/epidemiología , Demencia/prevención & control , Factores de Riesgo , Estudios Longitudinales , Anciano , Persona de Mediana Edad , Estudios Transversales , Envejecimiento , Prevalencia , Anciano de 80 o más Años , Obesidad/epidemiología , Hipertensión/epidemiología , Trastornos del Sueño-Vigilia/epidemiología , Pérdida Auditiva/epidemiología
15.
Stat Med ; 32(29): 5077-90, 2013 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-23824874

RESUMEN

The performance of a diagnostic tool yielding quantitative or ordinal measurements is often assessed in terms of its area under the receiver operating characteristic curve (AUC). As new diagnostic tools are constantly being developed, a frequently occurring task is to compare multiple AUCs as derived from the same group of subjects. For this purpose, previous methods have usually used an omnibus chi-square test, which may not be very informative. We present here methods for comparing several correlated AUCs using simultaneous confidence intervals. To improve small sample properties, we adopt the method of variance estimates recovery in which confidence limits for each AUC are obtained on the basis of the logit and inverse hyperbolic sine transformations. A simulation study demonstrates the superior performance of the proposed approach. The methods are illustrated with two examples.


Asunto(s)
Área Bajo la Curva , Intervalos de Confianza , Pruebas Diagnósticas de Rutina/métodos , Curva ROC , Niño , Simulación por Computador , Pruebas Diagnósticas de Rutina/normas , Femenino , Humanos , Obstrucción Intestinal/complicaciones , Obstrucción Intestinal/cirugía , Miopía/etiología , Estado Nutricional , Neoplasias Ováricas/complicaciones , Neoplasias Ováricas/cirugía
16.
Clin Transl Gastroenterol ; 14(11): e00629, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37578211

RESUMEN

INTRODUCTION: Phase 2 trials are fundamental to the rational and efficient design of phase 3 trials. We aimed to determine the relationship of treatment effect size estimates from phase 2 and phase 3 clinical trials on advanced therapeutics in inflammatory bowel disease. METHODS: MEDLINE, EMBASE, CENTRAL, and the Cochrane library were searched from inception to December 19, 2022, to identify paired phase 2 and 3 placebo-controlled induction studies of advanced therapeutics for Crohn's disease (CD) and ulcerative colitis (UC). Treatment effect sizes were expressed as a risk ratio (RR) between the active arm and placebo arm. For the same therapeutics, RRs from phase 2 trials were divided by the RR from phase 3 trial to quantify the relationship of effect sizes between phases. RESULTS: Twenty-two studies (9 phase 2 trials, 13 phase 3 trials) were included for CD and 30 studies (12 phase 2 trials, 18 phase 3 trials) for UC. In UC (pooled RR 0.72; 95% confidence interval: 0.58-0.86; RR <1 indicates smaller treatment effect sizes in phase 2 trials), but not CD (pooled RR 1.01; 95% confidence interval: 0.84-1.18), phase 2 trials systematically underestimated treatment effect sizes for the primary endpoint compared with phase 3 trials. The underestimation was observed for clinical, but not endoscopic, endpoints in UC. DISCUSSION: Treatment effect sizes for the primary and clinical endpoints were similar across clinical trial phases in CD, but not UC, where only endoscopic endpoints were comparable. This will help inform clinical development plans and future trial design.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Inducción de Remisión , Quimioterapia de Inducción , Ensayos Clínicos Fase III como Asunto , Ensayos Clínicos Fase II como Asunto
17.
J Prev Alzheimers Dis ; 10(4): 875-885, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37874110

RESUMEN

BACKGROUND/OBJECTIVES: CAN-THUMBS UP is designed as a comprehensive and innovative fully remote program to 1) develop an interactive and compelling online Brain Health Support Program intervention, with potential to positively influence dementia literacy, self-efficacy and lifestyle risk factors; 2) enroll and retain a community-dwelling Platform Trial Cohort of individuals at risk of dementia who will participate in the intervention; 3) support an open platform trial to test a variety of multidomain interventions that might further benefit individuals at risk of dementia. This manuscript presents the Brain Health Support Program Study protocol. DESIGN/SETTING: Twelve-month prospective multi-center longitudinal study to evaluate a fully remote web-based educational intervention. Participants will subsequently be part of a Platform Trial Cohort and may be eligible to participate in further dementia prevention clinical trials. PARTICIPANTS: Three hundred fifty older adults who are cognitively unimpaired or have mild cognitive impairment, with at least 1 well established dementia risk factor. INTERVENTION: Participants engage in the Brain Health Support Program intervention for 45-weeks and complete pre/post intervention measures. This intervention is designed to convey best available evidence for dementia prevention, consists of 181 chapters within 8 modules that are progressively delivered, and is available online in English and French. The program has been developed as a collaborative effort by investigators with recognized expertise in the program's content areas, along with input from older-adult citizen advisors. MEASUREMENTS: This study utilizes adapted remote assessments with accessible technologies (e.g. videoconferencing, cognitive testing via computer and mobile phone, wearable devices to track physical activity and sleep, self-administered saliva sample collection). The primary outcome is change in dementia literacy, as measured by the Alzheimer's Disease Knowledge Scale. Secondary outcomes include change in self-efficacy; engagement using the online program; user satisfaction ratings; and evaluation of usability and acceptance. Exploratory outcomes include changes in attitudes toward dementia, modifiable risk factors, performance on the Neuropsychological Test Battery, performance on self-administered online cognitive assessments, and levels of physical activity and sleep; success of the national recruitment plan; and the distribution of age adjusted polygenic hazard scores. CONCLUSIONS: This fully remote study provides an accessible approach to research with all study activities being completed in the participants' home environment. This approach may reduce barriers to participation, provide an easier and less demanding participant experience, and reach a broader geography with recruitment from all regions of Canada. CAN-THUMBS UP represents a Canadian contribution to the global World-Wide FINGERS program (alz.org/wwfingers).


Asunto(s)
Enfermedad de Alzheimer , Encéfalo , Anciano , Humanos , Canadá , Estudios Longitudinales , Estudios Prospectivos
18.
Stat Med ; 31(29): 3972-81, 2012 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-22764084

RESUMEN

The number of subjects required to estimate the intraclass correlation coefficient in a reliability study has usually been determined on the basis of the expected width of a confidence interval. However, this approach fails to explicitly consider the probability of achieving the desired interval width and may thus provide sample sizes that are too small to have adequate chance of achieving the desired precision. In this paper, we present a method that explicitly incorporates a prespecified probability of achieving the prespecified width or lower limit of a confidence interval. The resultant closed-form formulas are shown to be very accurate.


Asunto(s)
Modelos Estadísticos , Tamaño de la Muestra , Intervalos de Confianza , Humanos , Reproducibilidad de los Resultados , Proyectos de Investigación
19.
Alzheimers Res Ther ; 14(1): 94, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35820915

RESUMEN

BACKGROUND: Multidomain trials to prevent dementia by simultaneously targeting multiple risk factors with non-pharmacological lifestyle interventions show promise. Designing trials to evaluate the efficacy of individual interventions and their combinations is methodologically challenging. Determining the efficacy is, nevertheless, important to individuals, payers, and for resource allocations to support intervention implementation. MAIN BODY: The central rationale for seminal trials improving cardiovascular health or reducing falls risk in older adults is that multifactorial conditions may be amenable to improvement by simultaneously targeting multiple modifiable risk factors. Similar reasoning underlies lifestyle interventions to reduce dementia risk using combinations of physical exercise, cognitive training, diet, amelioration of vascular-metabolic risk factors, and improving sleep quality. Randomizing individuals with at least two modifiable risk factors to "standardly tailored" interventions to mitigate their risk factors, versus a comparator arm, will yield an unbiased estimate of the cumulative average effect of modifying more versus fewer risk factors. The between-group difference in the cognitive primary outcome will reflect both the main effects of the mitigated risk factors, as well as their synergistic effects. However, given the positive trial results, there are inherent challenges in quantifying post hoc which components, or combination of components, were responsible for improvements in cognition. Here, we elaborate on these methodological challenges and important considerations in using a standardly tailored design with two arms (one consisting of multidomain interventions tailored to participants' risk profiles and another consisting of active control conditions). We compare this approach to fully factorial designs and highlight the disadvantages and advantages of each. We discuss partial solutions, including analytical strategies such as risk reduction scores that measure reductions in the number or severity of risk factors in each study arm. Positive results can support the causal inference that between-group differences in the primary cognitive outcome were due to risk factor modification. CONCLUSION: Standardly tailored designs are pragmatic and feasible evaluations of multidomain interventions to reduce dementia risk. We propose sensitivity and exploratory analyses of between-group reductions in the severity of risk factors, as a methodology to bolster causal inferences that between-group differences in the primary cognitive outcome are due to the risk factors modified.


Asunto(s)
Demencia , Estilo de Vida , Anciano , Cognición , Demencia/prevención & control , Humanos , Factores de Riesgo , Conducta de Reducción del Riesgo
20.
J Crohns Colitis ; 16(5): 717-736, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34758084

RESUMEN

BACKGROUND: Precision in estimating placebo rates is important for clinical trial design. AIM: To quantify placebo rates across relevant endpoints in Crohn's disease [CD] trials and identify the factors influencing these rates in a contemporary meta-analysis. METHODS: We searched MEDLINE, EMBASE, and CENTRAL from inception to March 2021. Eligible studies were placebo-controlled trials of pharmacological interventions for CD. Placebo response and remission rates for induction and maintenance trials were extracted and pooled by random-effects to quantify placebo rates across studies. Mixed-effects meta-regression was used to evaluate the effects of study-level characteristics on placebo rates. RESULTS: In 125 studies [91 induction, 46 maintenance], placebo clinical remission and response rates for induction studies were 18% (95% confidence interval [CI] 16, 21%], and 32% [95% CI 29, 35%], respectively, and for maintenance studies were 28% [95% CI 23, 34%] and 30% [95% CI 24, 37%], respectively. Endoscopic remission and response rates in induction studies were 8% [95% CI 4, 18%] and 16% [95% CI 11, 23%], respectively. Trials enrolling patients with prior biologic exposure, longer disease duration, and higher CD activity index scores were associated with lower placebo clinical remission rates. Increased duration of follow-up, more follow-up visits, and a greater proportion of patients with colonic disease distribution were associated with higher clinical placebo rates. CONCLUSIONS: Placebo remission and response rates in CD trials vary according to the phase of the trial, endpoint assessed, and induction or maintenance design. These contemporary estimates will help to inform future CD trial design.


Asunto(s)
Enfermedad de Crohn , Enfermedad de Crohn/tratamiento farmacológico , Humanos , Quimioterapia de Inducción , Quimioterapia de Mantención , Ensayos Clínicos Controlados Aleatorios como Asunto , Inducción de Remisión
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