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1.
Biostatistics ; 25(1): 220-236, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36610075

RESUMO

Trial-level surrogates are useful tools for improving the speed and cost effectiveness of trials but surrogates that have not been properly evaluated can cause misleading results. The evaluation procedure is often contextual and depends on the type of trial setting. There have been many proposed methods for trial-level surrogate evaluation, but none, to our knowledge, for the specific setting of platform studies. As platform studies are becoming more popular, methods for surrogate evaluation using them are needed. These studies also offer a rich data resource for surrogate evaluation that would not normally be possible. However, they also offer a set of statistical issues including heterogeneity of the study population, treatments, implementation, and even potentially the quality of the surrogate. We propose the use of a hierarchical Bayesian semiparametric model for the evaluation of potential surrogates using nonparametric priors for the distribution of true effects based on Dirichlet process mixtures. The motivation for this approach is to flexibly model relationships between the treatment effect on the surrogate and the treatment effect on the outcome and also to identify potential clusters with differential surrogate value in a data-driven manner so that treatment effects on the surrogate can be used to reliably predict treatment effects on the clinical outcome. In simulations, we find that our proposed method is superior to a simple, but fairly standard, hierarchical Bayesian method. We demonstrate how our method can be used in a simulated illustrative example (based on the ProBio trial), in which we are able to identify clusters where the surrogate is, and is not useful. We plan to apply our method to the ProBio trial, once it is completed.


Assuntos
Ensaios Clínicos como Assunto , Humanos , Teorema de Bayes , Resultado do Tratamento
2.
J Pineal Res ; 76(5): e12985, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38888087

RESUMO

Previous studies have reported inconsistent results about exogenous melatonin's sleep-promoting effects. A possible explanation relies on the heterogeneity in administration schedule and dose, which might be accountable for differences in treatment efficacy. In this paper, we undertook a systematic review and meta-analysis of double-blind, randomized controlled trials performed on patients with insomnia and healthy volunteers, evaluating the effect of melatonin administration on sleep-related parameters. The standardized mean difference between treatment and placebo groups in terms of sleep onset latency and total sleep time were used as outcomes. Dose-response and meta-regression models were estimated to explore how time of administration, dose, and other treatment-related parameters might affect exogenous melatonin's efficacy. We included 26 randomized controlled trials published between 1987 and 2020, for a total of 1689 observations. Dose-response meta-analysis showed that melatonin gradually reduces sleep onset latency and increases total sleep time, peaking at 4 mg/day. Meta-regression models showed that insomnia status (ß = 0.50, p < 0.001) and time between treatment administration and the sleep episode (ß = -0.16, p = 0.023) were significant predictors of sleep onset latency, while the time of day (ß = -0.086, p < 0.01) was the only significant predictor of total sleep time. Our results suggest that advancing the timing of administration (3 h before the desired bedtime) and increasing the administered dose (4 mg/day), as compared to the exogenous melatonin schedule most used in clinical practice (2 mg 30 min before the desired bedtime), might optimize the efficacy of exogenous melatonin in promoting sleep.


Assuntos
Melatonina , Ensaios Clínicos Controlados Aleatórios como Assunto , Distúrbios do Início e da Manutenção do Sono , Melatonina/administração & dosagem , Humanos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Relação Dose-Resposta a Droga , Sono/efeitos dos fármacos
3.
Br J Cancer ; 129(1): 61-71, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37149701

RESUMO

BACKGROUND: Adherence to adjuvant tamoxifen therapy is suboptimal, and acceptance of tamoxifen for primary prevention is poor. Published results indicate effect of low-dose tamoxifen therapy. Using questionnaire data from a randomised controlled trial, we describe side effects of standard and low-dose tamoxifen in healthy women. METHODS: In the KARISMA trial, 1440 healthy women were randomised to 6 months of daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. Participants completed a 48-item, five-graded Likert score symptom questionnaire at baseline and follow-up. Linear regression models were used to identify significant changes in severity levels across doses and by menopausal status. RESULTS: Out of 48 predefined symptoms, five were associated with tamoxifen exposure (hot flashes, night sweats, cold sweats, vaginal discharge and muscle cramps). When comparing these side effects in premenopausal women randomised to low doses (2.5, 5 mg) versus high doses (10, 20 mg), the mean change was 34% lower in the low-dose group. No dose-dependent difference was seen in postmenopausal women. CONCLUSIONS: Symptoms related to tamoxifen therapy are influenced by menopausal status. Low-dose tamoxifen, in contrast to high-dose, was associated with less pronounced side effects, a finding restricted to premenopausal women. Our findings give new insights which may influence future dosing strategies of tamoxifen in both the adjuvant and preventive settings. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03346200.


Assuntos
Neoplasias da Mama , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Tamoxifeno/uso terapêutico , Fogachos/induzido quimicamente , Fogachos/tratamento farmacológico , Fogachos/prevenção & controle , Pré-Menopausa , Inquéritos e Questionários , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/induzido quimicamente , Antineoplásicos Hormonais/efeitos adversos
4.
BJU Int ; 132(6): 696-704, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37704215

RESUMO

OBJECTIVE: To evaluate the performance of risk calculators (RCs) predicting lymph node invasion (LNI) and extraprostatic extension (EPE) in men undergoing transperineal magnetic resonance imaging/transrectal ultrasound (TRUS)-fusion template saturation biopsy (TTSB) and conventional systematic TRUS-guided biopsy (SB). PATIENTS AND METHODS: The RCs were tested in a consecutive cohort of 645 men undergoing radical prostatectomy with extended pelvic LN dissection between 2005 and 2019. TTSB was performed in 230 (35.7%) and SB in 415 (64.3%) men. Risk of LNI and EPE was calculated using the available RCs. Discrimination, calibration, and clinical usefulness stratified by different biopsy techniques were assessed. RESULTS: Lymph node invasion was observed in 23 (10%) and EPE in 73 (31.8%) of cases with TTSB and 53 (12.8%) and 158 (38%) with SB, respectively. RCs showed an excellent discrimination and acceptable calibration for prediction of LNI based on TTSB (area under the curve [AUC]/risk estimation: Memorial Sloan Kettering Cancer Center [MSKCC]-RC 0.79/-4%, Briganti (2012)-RC 0.82/-4%, Gandaglia-RC 0.81/+6%). These were comparable in SB (MSKCC-RC 0.78/+2%; Briganti (2012)-RC 0.77/-3%). Decision curve analysis (DCA) revealed a net benefit at threshold probabilities between 3% and 6% when TTSB was used. For prediction of EPE based on TTSB an inferior discrimination and variable calibration were observed (AUC/risk estimation: MSKCC-RC 0.71/+8% and Martini (2018)-RC 0.69/+2%) achieving a net benefit on DCA only at risk thresholds of >17%. Performance of RCs for prediction of LNI and EPE based on SB showed comparable results with a better performance in the DCA for LNI (risk thresholds 1-2%) and poorer performance for EPE (risk threshold >20%). This study is limited by its retrospective single-institution design. CONCLUSIONS: The potentially more accurate grading ability of TTSB did not result in improved performance of preoperative RCs. Prediction tools for LNI proved clinical usefulness while RCs for EPE did not.


Assuntos
Nomogramas , Neoplasias da Próstata , Masculino , Humanos , Estudos Retrospectivos , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Linfonodos/patologia , Biópsia , Prostatectomia , Biópsia Guiada por Imagem/métodos
5.
Br J Sports Med ; 57(15): 979-989, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36854652

RESUMO

OBJECTIVE: To estimate the dose-response associations between non-occupational physical activity and several chronic disease and mortality outcomes in the general adult population. DESIGN: Systematic review and cohort-level dose-response meta-analysis. DATA SOURCES: PubMed, Scopus, Web of Science and reference lists of published studies. ELIGIBILITY CRITERIA: Prospective cohort studies with (1) general population samples >10 000 adults, (2) ≥3 physical activity categories, and (3) risk measures and CIs for all-cause mortality or incident total cardiovascular disease, coronary heart disease, stroke, heart failure, total cancer and site-specific cancers (head and neck, myeloid leukaemia, myeloma, gastric cardia, lung, liver, endometrium, colon, breast, bladder, rectum, oesophagus, prostate, kidney). RESULTS: 196 articles were included, covering 94 cohorts with >30 million participants. The evidence base was largest for all-cause mortality (50 separate results; 163 415 543 person-years, 811 616 events), and incidence of cardiovascular disease (37 results; 28 884 209 person-years, 74 757 events) and cancer (31 results; 35 500 867 person-years, 185 870 events). In general, higher activity levels were associated with lower risk of all outcomes. Differences in risk were greater between 0 and 8.75 marginal metabolic equivalent of task-hours per week (mMET-hours/week) (equivalent to the recommended 150 min/week of moderate-to-vigorous aerobic physical activity), with smaller marginal differences in risk above this level to 17.5 mMET-hours/week, beyond which additional differences were small and uncertain. Associations were stronger for all-cause (relative risk (RR) at 8.75 mMET-hours/week: 0.69, 95% CI 0.65 to 0.73) and cardiovascular disease (RR at 8.75 mMET-hours/week: 0.71, 95% CI 0.66 to 0.77) mortality than for cancer mortality (RR at 8.75 mMET-hours/week: 0.85, 95% CI 0.81 to 0.89). If all insufficiently active individuals had achieved 8.75 mMET-hours/week, 15.7% (95% CI 13.1 to 18.2) of all premature deaths would have been averted. CONCLUSIONS: Inverse non-linear dose-response associations suggest substantial protection against a range of chronic disease outcomes from small increases in non-occupational physical activity in inactive adults. PROSPERO registration number CRD42018095481.


Assuntos
Doenças Cardiovasculares , Neoplasias , Masculino , Adulto , Feminino , Humanos , Estudos Prospectivos , Doenças Cardiovasculares/prevenção & controle , Exercício Físico/fisiologia , Doença Crônica
6.
Int J Neuropsychopharmacol ; 24(8): 601-614, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-33890987

RESUMO

BACKGROUND: Negative symptoms are a core aspect of psychopathology in schizophrenia. Currently available pharmacological agents have proven minimally efficacious for remediating negative symptoms. A promising treatment avenue is the intranasal administration of the neuropeptide oxytocin. However, there have been inconsistencies in effects of oxytocin on negative symptoms throughout the literature, and factors leading to inconsistent effects are unclear. METHODS: We conducted a systematic review and meta-analysis of randomized clinical trials to compare the effectiveness of oxytocin with placebo for the treatment of negative symptoms and determine moderators of treatment effect. Random effects meta-analyses and dose-response meta-analysis were performed on mean changes in negative symptoms. RESULTS: In an initial analysis of all 9 identified randomized clinical trials, intranasal oxytocin showed no significant effect on negative symptoms. For higher doses (>40-80 IU), a beneficial effect on negative symptoms was found with a moderate effect size, but this effect disappeared after exclusion of 1 outlier study. The dose-response meta-analysis predicted that higher doses of oxytocin may be more efficacious for negative symptoms. For positive symptoms, no beneficial effect of oxytocin was found in the main meta-analysis, but the dose-response meta-analysis suggested a potential advantage of higher doses. CONCLUSIONS: The present results show no consistent beneficial effect of intranasal oxytocin for the treatment of negative and positive symptoms. The dose-response meta-analysis does not allow drawing any firm conclusions but suggests that high doses of intranasal oxytocin may be more efficacious. If future studies are conducted, an effort to reach adequate CNS concentrations for a sufficient duration is required.


Assuntos
Ocitocina/farmacologia , Esquizofrenia/tratamento farmacológico , Administração Intranasal , Relação Dose-Resposta a Droga , Humanos , Avaliação de Resultados em Cuidados de Saúde , Ocitocina/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Esquizofrenia/fisiopatologia
7.
BJU Int ; 127(5): 585-595, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33058469

RESUMO

OBJECTIVES: To evaluate the postoperative complication and mortality rate following laparoscopic radical cystectomy (RARC) with intracorporeal urinary diversion (ICUD) in octogenarians. PATIENTS AND METHODS: We conducted a retrospective analysis comparing postoperative complication and mortality rates depending on age in a consecutive series of 1890 patients who underwent RARC with ICUD for bladder cancer between 2004 and 2018 in 10 European centres. Outcomes of patients aged <80 years and those aged ≥80 years were compared with regard to postoperative complications (Clavien-Dindo grading) and mortality rate. Cancer-specific mortality (CSM) and other-cause mortality (OCM) after surgery were calculated using the non-parametric Aalen-Johansen estimator. RESULTS: A total of 1726 patients aged <80 years and 164 aged ≥80 years were included in the analysis. The 30- and 90-day rate for high-grade (Clavien-Dindo grades III-V) complications were 15% and 21% for patients aged <80 years compared to 11% and 13% for patients aged ≥80 years (P = 0.2 and P = 0.03), respectively. In a multivariable logistic regression analysis adjusting for pre- and postoperative variables, age ≥80 years was not an independent predictor of high-grade complications (odds ratio 0.6, 95% confidence interval 0.3-1.1; P = 0.12). The non-cancer-related 90-day mortality was 2.3% for patients aged ≥80 years and 1.8% for those aged <80 years, respectively (P = 0.7). The estimated 12-month CSM and OCM rates for those aged <80 years were 8% and 3%, and for those aged ≥80 years, 15% and 8%, respectively (P = 0.009 and P < 0.001). CONCLUSIONS: The minimally invasive approach to RARC with ICUD for bladder cancer in well-selected elderly patients (aged ≥80 years) achieved a tolerable high-grade complication rate; the 90-day postoperative mortality rate was driven by cancer progression and the non-cancer-related rate was equivalent to that of patients aged <80 years. However, an increased OCM rate in this elderly group after the first year should be taken into account. These results will support clinicians and patients when balancing cancer-related vs treatment-related risks and benefits.


Assuntos
Cistectomia/mortalidade , Complicações Pós-Operatórias/epidemiologia , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/mortalidade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Cistectomia/efeitos adversos , Europa (Continente)/epidemiologia , Feminino , Humanos , Excisão de Linfonodo/efeitos adversos , Excisão de Linfonodo/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/mortalidade , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , Derivação Urinária/efeitos adversos
8.
World J Urol ; 39(4): 1153-1159, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32472278

RESUMO

PURPOSE: To describe the predictive value of information on previous benign biopsy for the outcome of MRI-targeted biopsies. METHODS: An exploratory analysis was conducted using data from a prospective, multicenter, paired diagnostic study of 532 men undergoing diagnostics for prostate cancer during 2016-2017. All men underwent 1.5 T MRI; systematic prostate biopsies; and MRI-targeted biopsies to MRI lesions with Prostate Imaging Reporting and Data System version 2, PI-RADS ≥ 3. The main outcome was numbers of detected prostate cancer characterized by grade group (GG) where GG ≥ 2 defined clinically significant cancer (csPCa). RESULTS: Men with previous biopsies had significantly more often negative MRI (26% vs. 17%, p < 0.05) compared to men without previous biopsies. Men with previous biopsies showed higher rates of benign biopsies (41% vs. 26%, p < 0.05) and lower rates of GG2 (17% vs. 30%, p < 0.05) and GG ≥ 3 (5% vs. 10%, p < 0.05) cancer. Biopsy-naïve men had higher proportions of highly suspicious MRI lesions (PIRADS 5; p < 0.05) and a higher proportion of significant cancer in those lesions (p = 0.05). In multivariate regression analysis, a previous benign prostate biopsy was associated with less than half the odds of csPCa (OR 0.38; 95% CI 0.20-0.71). CONCLUSION: In this large prospective multicenter trial, we showed that men with a previous prostate biopsy had higher proportions of MRIs without lesions and lower proportion of highly suspicious lesions than biopsy-naïve men. Further, biopsy-naïve men showed higher detection of clinically significant cancer when using MRI-targeted biopsies. Also, in the era of MRI-targeted biopsy strategies, biopsy history should be carefully considered in biopsy decisions. TRIAL REGISTRATION: NCT02788825 (ClinicalTrials.gov). Date of registration June 2, 2016.


Assuntos
Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Humanos , Masculino , Anamnese , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Br J Sports Med ; 54(20): 1195-1201, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31406017

RESUMO

OBJECTIVES: To systematically review and analyse studies of high amounts of physical activity and mortality risk in the general population. ELIGIBILITY CRITERIA: Inclusion criteria related to follow-up (minimum 2 years), outcome (mortality from all causes, cancer, cardiovascular disease (CVD) or coronary heart disease), exposure (eg, a category of >1000 metabolic equivalent of task (MET) min/week), study design (prospective cohort, nested case control or case-cohort) and reports of cases and person years of exposure categories. INFORMATION SOURCES: Systematic searches were conducted in Embase and Pubmed from database inception to 2 March 2019. RISK OF BIAS: The quality of the studies was assessed with the Newcastle-Ottawa scale. INCLUDED STUDIES: From 31 368 studies identified, 48 were included. Two authors independently extracted outcome estimates and assessed study quality. SYNTHESIS OF RESULTS: We estimated hazard ratios (HRs) using random effect restricted cubic spline dose-response meta-analyses. Compared with the recommended level of physical activity (750 MET min/week), mortality risk was lower at physical activity levels exceeding the recommendations, at least until 5000 MET min/week for all cause mortality (HR=0.86, 95% CI 0.78 to 0.94) and for CVD mortality (HR=0.73, 95% CI 0.56 to 0.95). STRENGTHS AND LIMITATIONS OF EVIDENCE: The strengths of this study include the detailed dose-response analyses, inclusion of 48 studies and examination of sources of heterogeneity. The limitations include the observational nature of the included studies and the inaccurate estimations of amount of physical activity. INTERPRETATION: Compared with the recommended level, mortality risk was lower at physical activity levels well above the recommended target range. Further, there was no threshold beyond which lifespan was compromised. REGISTRATION: PROSPERO CRD42017055727.


Assuntos
Exercício Físico , Mortalidade , Doenças Cardiovasculares/mortalidade , Causas de Morte , Doença das Coronárias/mortalidade , Metabolismo Energético , Humanos , Neoplasias/mortalidade , Fatores de Risco
10.
Eur J Nutr ; 57(2): 689-701, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28070638

RESUMO

BACKGROUND/OBJECTIVES: Several epidemiological studies have analyzed the associations between red and processed meat and bladder cancer risk but the shape and strength of the associations are still unclear. Therefore, we conducted a dose-response meta-analysis to quantify the potential association between red and processed meat and bladder cancer risk. METHODS: Relevant studies were identified by searching the PubMed database through January 2016 and reviewing the reference lists of the retrieved articles. Results were combined using random-effects models. RESULTS: Five cohort studies with 3262 cases and 1,038,787 participants and 8 cases-control studies with 7009 cases and 27,240 participants met the inclusion criteria. Red meat was linearly associated with bladder cancer risk in case-control studies, with a pooled RR of 1.51 (95% confidence interval (CI) 1.13, 2.02) for every 100 g increase per day, while no association was observed among cohort studies (P heterogeneity across study design = 0.02). Based on both case-control and cohort studies, the pooled relative risk (RR) for every 50 g increase of processed meat per day was 1.20 (95% CI 1.06, 1.37) (P heterogeneity across study design = 0.22). CONCLUSIONS: This meta-analysis suggests that processed meat may be positively associated with bladder cancer risk. A positive association between red meat and risk of bladder cancer was observed only in case-control studies, while no association was observe in prospective studies.


Assuntos
Dieta/efeitos adversos , Medicina Baseada em Evidências , Alimentos em Conserva/efeitos adversos , Produtos da Carne/efeitos adversos , Carne/efeitos adversos , Neoplasias da Bexiga Urinária/etiologia , Animais , Bovinos , Humanos , Incidência , Reprodutibilidade dos Testes , Fatores de Risco , Carneiro Doméstico , Sus scrofa , Neoplasias da Bexiga Urinária/epidemiologia
11.
Diabetologia ; 59(12): 2527-2545, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27747395

RESUMO

AIMS/HYPOTHESIS: Inverse associations between physical activity (PA) and type 2 diabetes mellitus are well known. However, the shape of the dose-response relationship is still uncertain. This review synthesises results from longitudinal studies in general populations and uses non-linear models of the association between PA and incident type 2 diabetes. METHODS: A systematic literature search identified 28 prospective studies on leisure-time PA (LTPA) or total PA and risk of type 2 diabetes. PA exposures were converted into metabolic equivalent of task (MET) h/week and marginal MET (MMET) h/week, a measure only considering energy expended above resting metabolic rate. Restricted cubic splines were used to model the exposure-disease relationship. RESULTS: Our results suggest an overall non-linear relationship; using the cubic spline model we found a risk reduction of 26% (95% CI 20%, 31%) for type 2 diabetes among those who achieved 11.25 MET h/week (equivalent to 150 min/week of moderate activity) relative to inactive individuals. Achieving twice this amount of PA was associated with a risk reduction of 36% (95% CI 27%, 46%), with further reductions at higher doses (60 MET h/week, risk reduction of 53%). Results for the MMET h/week dose-response curve were similar for moderate intensity PA, but benefits were greater for higher intensity PA and smaller for lower intensity activity. CONCLUSIONS/INTERPRETATION: Higher levels of LTPA were associated with substantially lower incidence of type 2 diabetes in the general population. The relationship between LTPA and type 2 diabetes was curvilinear; the greatest relative benefits are achieved at low levels of activity, but additional benefits can be realised at exposures considerably higher than those prescribed by public health recommendations.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Exercício Físico/fisiologia , Animais , Humanos , Atividades de Lazer , Atividade Motora/fisiologia , Estudos Prospectivos , Fatores de Risco
12.
Stat Med ; 35(21): 3661-75, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27161124

RESUMO

Assessing the magnitude of heterogeneity in a meta-analysis is important for determining the appropriateness of combining results. The most popular measure of heterogeneity, I(2) , was derived under an assumption of homogeneity of the within-study variances, which is almost never true, and the alternative estimator, R^I, uses the harmonic mean to estimate the average of the within-study variances, which may also lead to bias. This paper thus presents a new measure for quantifying the extent to which the variance of the pooled random-effects estimator is due to between-studies variation, R^b, that overcomes the limitations of the previous approach. We show that this measure estimates the expected value of the proportion of total variance due to between-studies variation and we present its point and interval estimators. The performance of all three heterogeneity measures is evaluated in an extensive simulation study. A negative bias for R^b was observed when the number of studies was very small and became negligible as the number of studies increased, while R^I and I(2) showed a tendency to overestimate the impact of heterogeneity. The coverage of confidence intervals based upon R^b was good across different simulation scenarios but was substantially lower for R^I and I(2) , especially for high values of heterogeneity and when a large number of studies were included in the meta-analysis. The proposed measure is implemented in a user-friendly function available for routine use in r and sas. R^b will be useful in quantifying the magnitude of heterogeneity in meta-analysis and should supplement the p-value for the test of heterogeneity obtained from the Q test. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Metanálise como Assunto , Viés , Intervalos de Confiança , Humanos , Estatística como Assunto
13.
BMC Med Res Methodol ; 16: 91, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27485429

RESUMO

BACKGROUND: Meta-analytical methods are frequently used to combine dose-response findings expressed in terms of relative risks. However, no methodology has been established when results are summarized in terms of differences in means of quantitative outcomes. METHODS: We proposed a two-stage approach. A flexible dose-response model is estimated within each study (first stage) taking into account the covariance of the data points (mean differences, standardized mean differences). Parameters describing the study-specific curves are then combined using a multivariate random-effects model (second stage) to address heterogeneity across studies. RESULTS: The method is fairly general and can accommodate a variety of parametric functions. Compared to traditional non-linear models (e.g. E max, logistic), spline models do not assume any pre-specified dose-response curve. Spline models allow inclusion of studies with a small number of dose levels, and almost any shape, even non monotonic ones, can be estimated using only two parameters. We illustrated the method using dose-response data arising from five clinical trials on an antipsychotic drug, aripiprazole, and improvement in symptoms in shizoaffective patients. Using the Positive and Negative Syndrome Scale (PANSS), pooled results indicated a non-linear association with the maximum change in mean PANSS score equal to 10.40 (95 % confidence interval 7.48, 13.30) observed for 19.32 mg/day of aripiprazole. No substantial change in PANSS score was observed above this value. An estimated dose of 10.43 mg/day was found to produce 80 % of the maximum predicted response. CONCLUSION: The described approach should be adopted to combine correlated differences in means of quantitative outcomes arising from multiple studies. Sensitivity analysis can be a useful tool to assess the robustness of the overall dose-response curve to different modelling strategies. A user-friendly R package has been developed to facilitate applications by practitioners.


Assuntos
Antipsicóticos/farmacologia , Metanálise como Assunto , Algoritmos , Antipsicóticos/uso terapêutico , Relação Dose-Resposta a Droga , Humanos , Dinâmica não Linear , Ensaios Clínicos Controlados Aleatórios como Assunto , Processos Estocásticos
14.
Am J Epidemiol ; 180(8): 763-75, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25156996

RESUMO

Several studies have analyzed the relationship between coffee consumption and mortality, but the shape of the association remains unclear. We conducted a dose-response meta-analysis of prospective studies to examine the dose-response associations between coffee consumption and mortality from all causes, cardiovascular disease (CVD), and all cancers. Pertinent studies, published between 1966 and 2013, were identified by searching PubMed and by reviewing the reference lists of the selected articles. Prospective studies in which investigators reported relative risks of mortality from all causes, CVD, and all cancers for 3 or more categories of coffee consumption were eligible. Results from individual studies were pooled using a random-effects model. Twenty-one prospective studies, with 121,915 deaths and 997,464 participants, met the inclusion criteria. There was strong evidence of nonlinear associations between coffee consumption and mortality for all causes and CVD (P for nonlinearity < 0.001). The largest risk reductions were observed for 4 cups/day for all-cause mortality (16%, 95% confidence interval: 13, 18) and 3 cups/day for CVD mortality (21%, 95% confidence interval: 16, 26). Coffee consumption was not associated with cancer mortality. Findings from this meta-analysis indicate that coffee consumption is inversely associated with all-cause and CVD mortality.


Assuntos
Doenças Cardiovasculares/mortalidade , Café , Neoplasias/mortalidade , Consumo de Bebidas Alcoólicas/epidemiologia , Doenças Cardiovasculares/epidemiologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Neoplasias/epidemiologia , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia
15.
J Consult Clin Psychol ; 92(5): 296-309, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38829329

RESUMO

OBJECTIVE: Evidence on the optimal "dose" of cognitive behavioral therapy (CBT) for treating major depressive disorder is sparse. This analysis aimed to evaluate the dose-response curve in CBT using a nonlinear approach, whereby "dose" was defined as number of treatment sessions. The dose-response curve of CBT was compared to other psychotherapies and pharmacological treatments for depression. METHOD: A systematic review and metaregression analysis of randomized controlled trials (RCTs) examining the efficacy of CBT in adults with acute depression was conducted. Treatment arms examining other psychosocial or pharmacological interventions were also analyzed. Cubic spline metaregression techniques were used to model nonlinear dose-response curves. RESULTS: Seventy-two studies and 7,377 participants were included. Modeling the dose-response curve between change of depression symptom severity and the number of CBT sessions resulted in a nonlinear curve characterized by a strong improvement in symptom severity from baseline within the first eight sessions. Symptom reduction continues in the further course of the treatment, but at a slower pace. A similar pattern of symptom development was found for other therapies as well, although the prominence of early improvement and overall effect sizes vary across treatment arms. CONCLUSION: Results imply a general tendency for the strongest alleviation of depressive symptom severity in early stages of CBT treatment, thus, if aiming at symptom alleviation, speak for short CBT interventions. However, these findings have to be discussed in the light of the limited data regarding the sustainability of treatment effects in short-term therapies and effects beyond symptomatic changes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Terapia Cognitivo-Comportamental , Transtorno Depressivo Maior , Humanos , Terapia Cognitivo-Comportamental/métodos , Transtorno Depressivo Maior/terapia , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
JAMA Netw Open ; 7(5): e2412616, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38776083

RESUMO

Importance: Noninvasive brain stimulation (NIBS) interventions have been shown to be efficacious in several mental disorders, but the optimal dose stimulation parameters for each disorder are unknown. Objective: To define NIBS dose stimulation parameters associated with the greatest efficacy in symptom improvement across mental disorders. Data Sources: Studies were drawn from an updated (to April 30, 2023) previous systematic review based on a search of PubMed, OVID, and Web of Knowledge. Study Selection: Randomized clinical trials were selected that tested transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) for any mental disorder in adults aged 18 years or older. Data Extraction and Synthesis: Two authors independently extracted the data. A 1-stage dose-response meta-analysis using a random-effects model was performed. Sensitivity analyses were conducted to test robustness of the findings. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Main Outcomes and Measures: The main outcome was the near-maximal effective doses of total pulses received for TMS and total current dose in coulombs for tDCS. Results: A total of 110 studies with 4820 participants (2659 men [61.4%]; mean [SD] age, 42.3 [8.8] years) were included. The following significant dose-response associations emerged with bell-shaped curves: (1) in schizophrenia, high-frequency (HF) TMS on the left dorsolateral prefrontal cortex (LDLPFC) for negative symptoms (χ2 = 9.35; df = 2; P = .009) and TMS on the left temporoparietal junction for resistant hallucinations (χ2 = 36.52; df = 2; P < .001); (2) in depression, HF-DLPFC TMS (χ2 = 14.49; df = 2; P < .001); (3) in treatment-resistant depression, LDLPFC tDCS (χ2 = 14.56; df = 2; P < .001); and (4) in substance use disorder, LDLPFC tDCS (χ2 = 33.63; df = 2; P < .001). The following significant dose-response associations emerged with plateaued or ascending curves: (1) in depression, low-frequency (LF) TMS on the right DLPFC (RDLPFC) with ascending curve (χ2 = 25.67; df = 2; P = .001); (2) for treatment-resistant depression, LF TMS on the bilateral DLPFC with ascending curve (χ2 = 5.86; df = 2; P = .004); (3) in obsessive-compulsive disorder, LF-RDLPFC TMS with ascending curve (χ2 = 20.65; df = 2; P < .001) and LF TMS on the orbitofrontal cortex with a plateaued curve (χ2 = 15.19; df = 2; P < .001); and (4) in posttraumatic stress disorder, LF-RDLPFC TMS with ascending curve (χ2 = 54.15; df = 2; P < .001). Sensitivity analyses confirmed the main findings. Conclusions and Relevance: The study findings suggest that NIBS yields specific outcomes based on dose parameters across various mental disorders and brain regions. Clinicians should consider these dose parameters when prescribing NIBS. Additional research is needed to prospectively validate the findings in randomized, sham-controlled trials and explore how other parameters contribute to the observed dose-response association.


Assuntos
Transtornos Mentais , Estimulação Transcraniana por Corrente Contínua , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Estimulação Transcraniana por Corrente Contínua/métodos , Transtornos Mentais/terapia , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
J Clin Psychiatry ; 84(2)2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36752753

RESUMO

Objective: To investigate the association of metabolic side effects with antipsychotic dose, we conducted a dose-response meta-analysis of randomized controlled trials (RCTs) in which antipsychotics were administered to people with schizophrenia. The primary outcome was mean change in weight. The secondary outcomes were the mean changes in metabolic parameters.Data Sources: MEDLINE, Embase, PubMed, PsyARTICLES, PsycINFO, Cochrane Database of Systematic Reviews, and different trial registries were searched for articles published in English until February 2021.Study Selection: We identified fixed-dose RCTs with first- or second-generation antipsychotics. The quality of RCTs was measured with Cochrane's Risk of Bias tool.Data Extraction: We performed a dose-response meta-analysis.Results: We retained 52 RCTs including 22,588 participants. With the exception of aripiprazole long-acting injectable (LAI), all investigated antipsychotics presented significant dose-response associations with weight, from lurasidone with a quasi-parabolic shaped curve (9 studies, estimation of 95% effective dose [ED95; 59.93 mg/d] = 0.53 kg/6 wk) to olanzapine LAI with a curve that continued to increase with the dose (1 study, ED95 [15.05 mg/d] = 4.29 kg/8 wk). All curves could be ordered in 3 different classes of shapes-quasi-parabolic, plateau, and ascending.Conclusions: We found significant dose-response associations for weight and metabolic variables, with a unique signature for each antipsychotic. Weight gain can occur at a relatively low median effective dose, and increasing doses can be associated with greater weight gain for some drugs. Despite several limitations, including the limited number of available studies, our results may provide useful information for preventing weight gain and metabolic disturbance by adapting antipsychotic doses.Registration: PROSPERO ID number CRD42021176569.


Assuntos
Antipsicóticos , Esquizofrenia , Humanos , Antipsicóticos/efeitos adversos , Benzodiazepinas/efeitos adversos , Revisões Sistemáticas como Assunto , Esquizofrenia/tratamento farmacológico , Esquizofrenia/induzido quimicamente , Aumento de Peso
18.
Lancet Digit Health ; 5(10): e703-e711, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37690911

RESUMO

BACKGROUND: Artificial intelligence (AI) as an independent reader of screening mammograms has shown promise, but there are few prospective studies. Our aim was to conduct a prospective clinical trial to examine how AI affects cancer detection and false positive findings in a real-world setting. METHODS: ScreenTrustCAD was a prospective, population-based, paired-reader, non-inferiority study done at the Capio Sankt Göran Hospital in Stockholm, Sweden. Consecutive women without breast implants aged 40-74 years participating in population-based screening in the geographical uptake area of the study hospital were included. The primary outcome was screen-detected breast cancer within 3 months of mammography, and the primary analysis was to assess non-inferiority (non-inferiority margin of 0·15 relative reduction in breast cancer diagnoses) of double reading by one radiologist plus AI compared with standard-of-care double reading by two radiologists. We also assessed single reading by AI alone and triple reading by two radiologists plus AI compared with standard-of-care double reading by two radiologists. This study is registered with ClinicalTrials.gov, NCT04778670. FINDINGS: From April 1, 2021, to June 9, 2022, 58 344 women aged 40-74 years underwent regular mammography screening, of whom 55 581 were included in the study. 269 (0·5%) women were diagnosed with screen-detected breast cancer based on an initial positive read: double reading by one radiologist plus AI was non-inferior for cancer detection compared with double reading by two radiologists (261 [0·5%] vs 250 [0·4%] detected cases; relative proportion 1·04 [95% CI 1·00-1·09]). Single reading by AI (246 [0·4%] vs 250 [0·4%] detected cases; relative proportion 0·98 [0·93-1·04]) and triple reading by two radiologists plus AI (269 [0·5%] vs 250 [0·4%] detected cases; relative proportion 1·08 [1·04-1·11]) were also non-inferior to double reading by two radiologists. INTERPRETATION: Replacing one radiologist with AI for independent reading of screening mammograms resulted in a 4% higher non-inferior cancer detection rate compared with radiologist double reading. Our study suggests that AI in the study setting has potential for controlled implementation, which would include risk management and real-world follow-up of performance. FUNDING: Swedish Research Council, Swedish Cancer Society, Region Stockholm, and Lunit.


Assuntos
Neoplasias da Mama , Mamografia , Feminino , Humanos , Masculino , Inteligência Artificial , Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Mamografia/métodos , Estudos Prospectivos , Suécia
19.
JAMA Netw Open ; 5(4): e228959, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35482309

RESUMO

Importance: Mortality rates resulting from bladder cancer have remained unchanged for more than 30 years. The surgical community has put hope in robot-assisted radical cystectomy (RARC) with intracorporeal urinary diversion (ICUD) in an effort to improve surgical outcomes and bladder cancer survival without strong supporting evidence. Objective: To evaluate perioperative, safety, and survival outcome differences between RARC with ICUD and open radical cystectomy (ORC). Design, Setting, and Participants: This nationwide population-based cohort study used data from the Swedish National Register of Urinary Bladder Cancer and population-based Cause of Death Register, which includes clinical information on tumor characteristics, treatment, and survival and covers approximately 97% of patients with urinary bladder cancer in Sweden. All patients who underwent radical cystectomy for bladder cancer in any hospital between January 2011 and December 2018 were included. Follow-up data were collected until December 2019. Data analysis was conducted from June to December 2020. Exposures: RARC or ORC. Main Outcomes and Measures: The main outcomes were all-cause and cancer-specific mortality between RARC and ORC, compared using propensity score matching. Secondary outcomes were differences in perioperative outcomes after the different surgical approaches. Results: Throughout the observation period, 889 patients underwent RARC and 2280 patients underwent ORC at 24 Swedish hospitals. The median (IQR) age was 71 (66-76) years and 2386 patients (75.3%) were men. After a median (IQR) follow-up of 47 (28-71) months, the 5-year cancer-specific mortality rates were 30.2% (variance, 1.59) for ORC and 27.6% (variance, 3.12) for RARC, and the overall survival rates were 57.7% (variance, 2.46) for ORC and 61.4% (variance, 5.11) for RARC. In the propensity score-matched analysis, RARC was associated with a lower all-cause mortality (hazard ratio, 0.71; 95% CI, 0.56-0.89; P = .004). Compared with ORC, RARC was associated with a lower estimated blood loss (median [IQR] 150 [100-300] mL vs 700 [400-1300] mL; P < .001), intraoperative transfusion rate (odds ratio [OR], 0.05; 95% CI, 0.03-0.08; P < .001), and shorter length of stay (median [IQR], 9 [6-13] days vs 13 [10-17] days; P < .001), and with a higher lymph node yield (median [IQR], 20 [15-27] lymph nodes vs 14 [8-24] lymph nodes; P < .001) and 90-day rehospitalization rate (OR, 1.28; 95% CI, 1.02-1.60; P = .03). The RARC group, compared with the ORC group had lower risk of Clavien-Dindo grade III or higher complications (OR, 0.62; 95% CI, 0.43-0.87; P = .009). Conclusions and Relevance: These findings suggest that compared with ORC, RARC with ICUD was associated with a lower overall mortality rate, fewer high-grade complications, and more favorable perioperative outcomes.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Neoplasias da Bexiga Urinária , Idoso , Estudos de Coortes , Cistectomia/efeitos adversos , Cistectomia/métodos , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Suécia/epidemiologia , Resultado do Tratamento , Neoplasias da Bexiga Urinária/cirurgia
20.
Prostate Cancer Prostatic Dis ; 25(2): 165-173, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34239046

RESUMO

BACKGROUND: Several studies evaluated prostate cancer (PCa) outcomes in Black men on active surveillance (AS); most studies contained few Black men and results were conflicting. We performed a systematic review and meta-analyze of race and outcomes on AS. METHODS: A systematic search was performed for articles of men with Grade Group 1 or 2 (GG1 or GG2) PCa on AS. All studies required race-specific comparative progression data. Progression to treatment, PSA, or biopsy progression were considered and relative risk (RR) estimates of Black men progressing were extracted and pooled using random-effects models. Differences by study-level characteristics were evaluated using subgroup and a cumulative meta-analysis by time. RESULTS: In total, 12 studies were included (3137 Black and 12,206 non-Black men); eight prospective (27%, n = 4210) and four retrospectives (73%, n = 11,133) cohorts. The overall RR of progression for Black men was 1.62 (95%CI, 1.21-2.17), I2 = 64% (95% CI, 32-80%), (χ2 = 30.23; P = 0.001; τ2 = 0.16). Black men with GG1 PCa alone had a higher pooled progression: RR = 1.81 (95% CI, 1.23-2.68). Including only studies with clinical progression (excluding progression to treatment), potentiated results: RR = 1.82 (95%CI, 1.27-2.60). However, a cumulative meta-analysis demonstrated decreasing pooled effect over time, with contemporary studies after 2019 showing a tempered effect (RR: 1.29, 95% CI: 1.20-1.39). CONCLUSIONS: Many studies attribute racial disparity in PCa to delayed presentation of disease, however, AS is unique since all AS eligible men have a low grade and stage PCa. Our findings suggest Black men may have an increased risk of progression during AS, but the association is not so strong that Black men should be discouraged from undergoing AS. Indeed, contemporary evidence suggests stricter inclusion, better confirmatory testing or better access to care may temper these findings. Importantly, these results utilize self-reported race, a social construct that has many limitations.


Assuntos
Neoplasias da Próstata , Biópsia , Humanos , Masculino , Gradação de Tumores , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/terapia , Conduta Expectante
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