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1.
AJNR Am J Neuroradiol ; 44(5): 582-588, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37105682

RESUMEN

BACKGROUND AND PURPOSE: The Systolic Blood Pressure Intervention (SPRINT) randomized trial demonstrated that intensive blood pressure management resulted in slower progression of cerebral white matter hyperintensities, compared with standard therapy. We assessed longitudinal changes in brain functional connectivity to determine whether intensive treatment results in less decline in functional connectivity and how changes in brain functional connectivity relate to changes in brain structure. MATERIALS AND METHODS: Five hundred forty-eight participants completed longitudinal brain MR imaging, including resting-state fMRI, during a median follow-up of 3.84 years. Functional brain networks were identified using independent component analysis, and a mean connectivity score was calculated for each network. Longitudinal changes in mean connectivity score were compared between treatment groups using a 2-sample t test, followed by a voxelwise t test. In the full cohort, adjusted linear regression analysis was performed between changes in the mean connectivity score and changes in structural MR imaging metrics. RESULTS: Four hundred six participants had longitudinal imaging that passed quality control. The auditory-salience-language network demonstrated a significantly larger decline in the mean connectivity score in the standard treatment group relative to the intensive treatment group (P = .014), with regions of significant difference between treatment groups in the cingulate and right temporal/insular regions. There was no treatment group difference in other networks. Longitudinal changes in mean connectivity score of the default mode network but not the auditory-salience-language network demonstrated a significant correlation with longitudinal changes in white matter hyperintensities (P = .013). CONCLUSIONS: Intensive treatment was associated with preservation of functional connectivity of the auditory-salience-language network, while mean network connectivity in other networks was not significantly different between intensive and standard therapy. A longitudinal increase in the white matter hyperintensity burden is associated with a decline in mean connectivity of the default mode network.


Asunto(s)
Encéfalo , Hipertensión , Humanos , Presión Sanguínea , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Hipertensión/diagnóstico por imagen , Hipertensión/tratamiento farmacológico , Mapeo Encefálico/métodos
2.
J Nutr Health Aging ; 22(10): 1148-1161, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30498820

RESUMEN

OBJECTIVES: Sarcopenia, defined as an age-associated loss of skeletal muscle function and muscle mass, occurs in approximately 6 - 22 % of older adults. This paper presents evidence-based clinical practice guidelines for screening, diagnosis and management of sarcopenia from the task force of the International Conference on Sarcopenia and Frailty Research (ICSFR). METHODS: To develop the guidelines, we drew upon the best available evidence from two systematic reviews paired with consensus statements by international working groups on sarcopenia. Eight topics were selected for the recommendations: (i) defining sarcopenia; (ii) screening and diagnosis; (iii) physical activity prescription; (iv) protein supplementation; (v) vitamin D supplementation; (vi) anabolic hormone prescription; (vii) medications under development; and (viii) research. The ICSFR task force evaluated the evidence behind each topic including the quality of evidence, the benefit-harm balance of treatment, patient preferences/values, and cost-effectiveness. Recommendations were graded as either strong or conditional (weak) as per the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Consensus was achieved via one face-to-face workshop and a modified Delphi process. RECOMMENDATIONS: We make a conditional recommendation for the use of an internationally accepted measurement tool for the diagnosis of sarcopenia including the EWGSOP and FNIH definitions, and advocate for rapid screening using gait speed or the SARC-F. To treat sarcopenia, we strongly recommend the prescription of resistance-based physical activity, and conditionally recommend protein supplementation/a protein-rich diet. No recommendation is given for Vitamin D supplementation or for anabolic hormone prescription. There is a lack of robust evidence to assess the strength of other treatment options.


Asunto(s)
Tamizaje Masivo/métodos , Sarcopenia/diagnóstico , Sarcopenia/terapia , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Sarcopenia/patología
3.
J Frailty Aging ; 7(3): 150-154, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30095144

RESUMEN

To reduce disability and dependence in older adults, frailty may represent an appropriate target for intervention. While preventing frailty through lifestyle interventions may be the optimal public health approach for many population groups, pharmacological approaches will likely be needed for individuals who meet frailty criteria or who have comorbid conditions that contribute to and complicate the frailty syndrome, and for those who are not compliant with lifestyle interventions. Barriers to successful development of drug treatments for frailty include variability in how the frailty syndrome is defined, lack of agreement on the best diagnostic tools and outcome measures, and the paucity of sensitive, reliable, and validated biomarkers. The International Conference on Frailty and Sarcopenia Research Task Force met in Miami, Florida, on February 28, 2018, to consider the status of treatments under development for frailty and discuss potential strategies for advancing the field. They concluded that at the present time, there may be a more productive regulatory pathway for adjuvant treatments or trials targeting specific functional outcomes such as gait speed. They also expressed optimism that several studies currently underway may provide the insight needed to advance drug development for frailty.


Asunto(s)
Ensayos Clínicos como Asunto/métodos , Fragilidad/tratamiento farmacológico , Proyectos de Investigación , Comités Consultivos , Anciano , Congresos como Asunto , Humanos
4.
Ageing Res Rev ; 46: 42-59, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29803716

RESUMEN

Growing evidence suggests chronic low-grade inflammation (LGI) as a possible mechanism underlying the aging process. Some biological and pharmaceutical compounds may reduce systemic inflammation and potentially avert functional decline occurring with aging. The aim of the present meta-analysis was to examine the association of pre-selected interventions on two established biomarkers of inflammation, interleukin-6 (IL-6), and C-reactive protein (CRP) in middle-age and older adults with chronic LGI. We reviewed the literature on potential anti-inflammatory compounds, selecting them based on safety, tolerability, acceptability, innovation, affordability, and evidence from randomized controlled trials. Six compounds met all five inclusion criteria for our systematic review and meta-analysis: angiotensin II receptor blockers (ARBs), metformin, omega-3, probiotics, resveratrol and vitamin D. We searched in MEDLINE, PubMed and EMBASE database until January 2017. A total of 49 articles fulfilled the selection criteria. Effect size of each study and pooled effect size for each compound were measured by the standardized mean difference. I2 was computed to measure heterogeneity of effects across studies. The following compounds showed a significant small to large effect in reducing IL-6 levels: probiotics (-0.68 pg/ml), ARBs (-0.37 pg/ml) and omega-3 (-0.19 pg/ml). For CRP, a significant small to medium effect was observed with probiotics (-0.43 mg/L), ARBs (-0.2 mg/L), omega-3 (-0.17 mg/L) and metformin (-0.16 mg/L). Resveratrol and vitamin D were not associated with any significant reductions in either biomarker. These results suggest that nutritional and pharmaceutical compounds can significantly reduce established biomarkers of systemic inflammation in middle-age and older adults. The findings should be interpreted with caution, however, due to the evidence of heterogeneity across the studies.


Asunto(s)
Envejecimiento/metabolismo , Dietoterapia/tendencias , Sistemas de Liberación de Medicamentos/tendencias , Medicina Basada en la Evidencia/tendencias , Estado Nutricional/fisiología , Anciano , Anciano de 80 o más Años , Envejecimiento/efectos de los fármacos , Envejecimiento/patología , Dietoterapia/métodos , Sistemas de Liberación de Medicamentos/métodos , Medicina Basada en la Evidencia/métodos , Humanos , Inflamación/metabolismo , Inflamación/patología , Inflamación/terapia , Persona de Mediana Edad
5.
Aging Clin Exp Res ; 30(6): 633-641, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28836178

RESUMEN

BACKGROUND: In older adults, impaired control of standing balance in the lateral direction is associated with the increased risk of falling. Assessing the factors that contribute to impaired standing balance control may identify areas to address to reduce falls risk. AIM: To investigate the contributions of physiological factors to standing lateral balance control. METHODS: Two hundred twenty-two participants from the Pittsburgh site of the Health, Aging and Body Composition Study had lateral balance control assessed using a clinical sensory integration balance test (standing on level and foam surface with eyes open and closed) and a lateral center of pressure tracking test using visual feedback. The center of pressure was recorded from a force platform. Multiple linear regression models examined contributors of lateral control of balance performance, including concurrently measured tests of lower extremity sensation, knee extensor strength, executive function, and clinical balance tests. Models were adjusted for age, body mass index, and sex. RESULTS: Larger lateral sway during the sensory integration test performed on foam was associated with longer repeated chair stands time. During the lateral center of pressure tracking task, the error in tracking increased at higher frequencies; greater error was associated with worse executive function. The relationship between sway performance and physical and cognitive function differed between women and men. DISCUSSION: Contributors to control of lateral balance were task-dependent. Lateral standing performance on an unstable surface may be more dependent upon general lower extremity strength, whereas visual tracking performance may be more dependent upon cognitive factors. CONCLUSIONS: Lateral balance control in ambulatory older adults is associated with deficits in strength and executive function.


Asunto(s)
Accidentes por Caídas , Equilibrio Postural/fisiología , Desempeño Psicomotor/fisiología , Anciano de 80 o más Años , Índice de Masa Corporal , Retroalimentación Sensorial , Femenino , Humanos , Extremidad Inferior , Masculino , Percepción , Postura/fisiología , Presión
6.
J Frailty Aging ; 5(1): 6-14, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26980363

RESUMEN

BACKGROUND: Converging evidence suggests that physical activity is an effective intervention for both clinical depression and sub-threshold depressive symptoms; however, findings are not always consistent. These mixed results might reflect heterogeneity in response to physical activity, with some subgroups of individuals responding positively, but not others. OBJECTIVES: 1) To examine the impact of genetic variation and sex on changes in depressive symptoms in older adults after a physical activity (PA) intervention, and 2) to determine if PA differentially improves particular symptom dimensions of depression. DESIGN: Randomized controlled trial. SETTING: Four field centers (Cooper Institute, Stanford University, University of Pittsburgh, and Wake Forest University). PARTICIPANTS: 396 community-dwelling adults aged 70-89 years who participated in the Lifestyle Interventions and Independence for Elders Pilot Study (LIFE-P). INTERVENTION: 12-month PA intervention compared to an education control. MEASUREMENTS: Polymorphisms in the serotonin transporter (5-HTT), brain-derived neurotrophic factor (BDNF), and apolipoprotein E (APOE) genes; 12-month change in the Center for Epidemiologic Studies Depression Scale total score, as well as scores on the depressed affect, somatic symptoms, and lack of positive affect subscales. RESULTS: Men randomized to the PA arm showed the greatest decreases in somatic symptoms, with a preferential benefit in male carriers of the BDNF Met allele. Symptoms of lack of positive affect decreased more in men compared to women, particularly in those possessing the 5-HTT L allele, but the effect did not differ by intervention arm. APOE status did not affect change in depressive symptoms. CONCLUSIONS: Results of this study suggest that the impact of PA on depressive symptoms varies by genotype and sex, and that PA may mitigate somatic symptoms of depression more than other symptoms. The results suggest that a targeted approach to recommending PA therapy for treatment of depression is viable.


Asunto(s)
Apolipoproteínas E/genética , Factor Neurotrófico Derivado del Encéfalo/genética , Depresión , Terapia por Ejercicio/métodos , Estilo de Vida , Actividad Motora , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Anciano , Anciano de 80 o más Años , Depresión/diagnóstico , Depresión/genética , Depresión/fisiopatología , Depresión/terapia , Femenino , Humanos , Vida Independiente/psicología , Masculino , Actividad Motora/genética , Actividad Motora/fisiología , Polimorfismo Genético , Escalas de Valoración Psiquiátrica , Factores Sexuales , Resultado del Tratamiento
7.
Osteoporos Int ; 27(6): 2109-16, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26856584

RESUMEN

UNLABELLED: Obesity appears protective against osteoporosis in cross-sectional studies. However, results from this longitudinal study found that obesity was associated with bone loss over time. Findings underscore the importance of looking at the longitudinal relationship, particularly given the increasing prevalence and duration of obesity among older adults. INTRODUCTION: Cross-sectional studies have found a positive association between body mass index (BMI) and bone mineral density (BMD), but little is known about the longitudinal relationship in US older adults. METHODS: We examined average annual rate of change in BMD by baseline BMI in the Health, Aging, and Body Composition Study. Repeated measurement of BMD was performed with dual-energy X-ray absorptiometry (DXA) at baseline and years 3, 5, 6, 8, and 10. Multivariate generalized estimating equations were used to predict mean BMD (femoral neck, total hip, and whole body) by baseline BMI (excluding underweight), adjusting for covariates. RESULTS: In the sample (n = 2570), 43 % were overweight and 24 % were obese with a mean baseline femoral neck BMD of 0.743 g/cm(2), hip BMD of 0.888 g/cm(2), and whole-body BMD of 1.09 g/cm(2). Change in total hip or whole-body BMD over time did not vary by BMI groups. However, obese older adults lost 0.003 g/cm(2) of femoral neck BMD per year more compared with normal weight older adults (p < 0.001). Femoral neck BMD change over time did not differ between the overweight and normal weight BMI groups (p = 0.74). In year 10, adjusted femoral neck BMD ranged from 0.696 g/cm(2) among obese, 0.709 g/cm(2) among normal weight, and 0.719 g/cm(2) among overweight older adults. CONCLUSIONS: Findings underscore the importance of looking at the longitudinal relationship between body composition and bone mineral density among older adults, indicating that high body mass may not be protective for bone loss over time.


Asunto(s)
Índice de Masa Corporal , Densidad Ósea , Absorciometría de Fotón , Anciano , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Estudios Longitudinales , Masculino , Factores de Tiempo
8.
J Clin Endocrinol Metab ; 100(4): 1343-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25642590

RESUMEN

CONTEXT: Higher dietary net acid loads have been associated with increased bone resorption, reduced bone mineral density (BMD), and increased fracture risk. OBJECTIVE: The objective was to compare bicarbonate (HCO3) measured in arterialized venous blood samples to skeletal outcomes. DESIGN: Arterialized venous samples collected from participants in the Health, Aging and Body Composition (Health ABC) Study were compared to BMD and rate of bone loss. SETTING: The setting was a community-based observational cohort. PARTICIPANTS: A total of 2287 men and women age 74 ± 3 years participated. INTERVENTION: Arterialized venous blood was obtained at the year 3 study visit and analyzed for pH and pCO2. HCO3 was determined using the Henderson-Hasselbalch equation. MAIN OUTCOME MEASURE: BMD was measured at the hip by dual-energy x-ray absorptiometry at the year 1 (baseline) and year 3 study visits. RESULTS: Plasma HCO3 was positively associated with BMD at both year 1 (P = .001) and year 3 (P = .001) in models adjusted for age, race, sex, clinic site, smoking, weight, and estimated glomerular filtration rate. Plasma HCO3 was inversely associated with rate of bone loss at the total hip over the 2.1 ± 0.3 (mean ± SD) years between the two bone density measurements (P < .001). Across quartiles of plasma HCO3, the rate of change in BMD over the 2.1 years ranged from a loss of 0.72%/y in the lowest quartile to a gain of 0.15%/y in the highest quartile of HCO3. CONCLUSIONS: Arterialized plasma HCO3 was associated positively with cross-sectional BMD and inversely with the rate of bone loss, implying that systemic acid-base status is an important determinant of skeletal health during aging. Ongoing bone loss was linearly related to arterialized HCO3, even after adjustment for age and renal function. Further research in this area may have major public health implications because reducing dietary net acid load is possible through dietary intervention or through supplementation with alkaline potassium compounds.


Asunto(s)
Envejecimiento/fisiología , Bicarbonatos/sangre , Densidad Ósea , Resorción Ósea , Osteoporosis/sangre , Anciano , Envejecimiento/sangre , Análisis de los Gases de la Sangre/métodos , Composición Corporal/fisiología , Resorción Ósea/sangre , Resorción Ósea/fisiopatología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Osteoporosis/fisiopatología
9.
Osteoarthritis Cartilage ; 23(3): 370-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25528106

RESUMEN

BACKGROUND: Vitamin K-dependent (VKD) proteins, including the mineralization inhibitor matrix-gla protein (MGP), are found in joint tissues including cartilage and bone. Previous studies suggest low vitamin K status is associated with higher osteoarthritis (OA) prevalence and incidence. OBJECTIVE: To clarify what joint tissues vitamin K is relevant to in OA, we investigated the cross-sectional and longitudinal association between vitamin K status and knee OA structural features measured using magnetic resonance imaging (MRI). METHODS: Plasma phylloquinone (PK, vitamin K1) and dephosphorylated-uncarboxylated MGP ((dp)ucMGP) were measured in 791 older community-dwelling adults who had bilateral knee MRIs (mean ± SD age = 74 ± 3 y; 67% female). The adjusted odds ratios (and 95% confidence intervals) [OR (95%CI)] for presence and progression of knee OA features according to vitamin K status were calculated using marginal models with generalized estimating equations (GEEs), adjusted for age, sex, body mass index (BMI), triglycerides and other pertinent confounders. RESULTS: Longitudinally, participants with very low plasma PK (<0.2 nM) were more likely to have articular cartilage and meniscus damage progression after 3 years [OR (95% CIs): 1.7(1.0-3.0), 2.6(1.3-5.2) respectively] compared to sufficient PK (≥ 1.0 nM). Higher plasma (dp)ucMGP (reflective of lower vitamin K status) was associated with higher odds of meniscus damage, osteophytes, bone marrow lesions, and subarticular cysts cross-sectionally [ORs (95% CIs) comparing highest to lowest quartile: 1.6(1.1-2.3); 1.7(1.1-2.5); 1.9(1.3-2.8); 1.5(1.0-2.1), respectively]. CONCLUSION: Community-dwelling men and women with very low plasma PK were more likely to have progression of articular cartilage and meniscus damage. Plasma (dp)ucMGP was associated with presence of knee OA features but not progression. Future studies are needed to clarify mechanisms underlying vitamin Ks role in OA.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Cartílago Articular/patología , Proteínas de la Matriz Extracelular/metabolismo , Meniscos Tibiales/patología , Osteoartritis de la Rodilla/metabolismo , Vitamina K 1/metabolismo , Deficiencia de Vitamina K/metabolismo , Anciano , Estudios de Cohortes , Estudios Transversales , Descarboxilación , Progresión de la Enfermedad , Femenino , Humanos , Incidencia , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Oportunidad Relativa , Osteoartritis de la Rodilla/epidemiología , Osteoartritis de la Rodilla/patología , Osteofito/epidemiología , Osteofito/metabolismo , Osteofito/patología , Fosforilación , Deficiencia de Vitamina K/epidemiología , Proteína Gla de la Matriz
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