José Fernando Gómez

The mobility gap between older men and women: The embodiment of gender

OBJECTIVES To present the study design and baseline results of the longitudinal International Mobility in Aging Study (IMIAS) on gender differences in physical performance and mobility disability prevalence in five diverse societies. METHODS Data are from surveys on random samples of people aged 65-74 years at Canadian (Kingston, Ontario; Saint-Hyacinthe, Quebec), Mediterranean (Tirana, Albania) and Latin American sites (Natal, Brazil; Manizales, Colombia) (N=1995). Mobility disability was defined as reporting difficulty in walking 400m or climbing stairs. Activities of daily living (ADL) disability was based on any self-reported difficulty in five mobility-related ADLs. The short physical performance battery (SPPB) was used to assess physical performance. Poisson regression models were fitted to estimate prevalence ratios. RESULTS Age-adjusted prevalence of low SPPB, mobility disability and ADL disability were higher in women than in men in all sites except for Kingston. After adjustment for education and income, gender differences in SPPB and ADL disability attenuated or disappeared in Saint-Hyacinthe and Manizales but remained large in Tirana and Natal and mobility disability remained more frequent in women than in men at all sites except Kingston. After further adjustment by chronic conditions and depressive symptoms, gender differences in mobility remained large at all sites except Kingston but only in Tirana did women have significantly poorer physical performance than men. DISCUSSION Results provide evidence for gender as a risk factor to explain poorer physical function in women and suggest that moving toward gender equality could attenuate the gender gap in physical function in old age.

Validez y fiabilidad de la escala de Braden para predecir riesgo de úlceras por presión en ancianos1

Objetivo Determinar la validez predictiva y la fiabilidad de la escala de Braden para predecir el riesgo de ulceras por presion (UP) en ancianos en una institucion de referencia de tercer nivel de atencion. DiseNo Estudio de cohorte. Material y mEtodos Se tomaron los 831 pacientes sin UP al ingreso, mayores de 60 anos, hospitalizados al menos durante 72 horas en el Hospital de Caldas durante un ano, septiembre 1988-1999. Las variables demograficas y el diagnostico primario al ingreso a las salas de hospitalizacion se tomaron de la historia clinica. Se clasifico el tipo de piel, se valoro el estado funcional mediante la escala de Barthel. La version original en ingles de la escala de Braden se tradujo al espanol y se aplico a las 72 horas del ingreso y cada semana hasta tres semanas, evaluando de forma simultanea el desarrollo de UP, las cuales se estadificaron de I a IV. La sensibilidad, la especificidad, el Valor Predictivo Positivo (VPP) y el Valor Predictivo Negativo (VPN) fueron calculados para los diferentes puntajes de la Escala de Braden en las cuatro aplicaciones o hasta la evaluacion anterior a la deteccion de la primera UP. Resultados El promedio de edad fue 71,9 (DE 8), 57% eran hombres y 96,9% procedian del hogar. El puntaje en la escala de Barthel oscilo entre 0 y 100 con una media de 46,9. En cuanto a los diagnosticos al ingreso las enfermedades cardiovasculares, osteomusculares, gastrointestinales y neurologicas fueron en su orden las patologias mas frecuentes. El 8,04% de los sujetos estudiados desarrollaron UP durante el estudio, 71,6% la desarrollaron durante la primera semana, 20,8% en la segunda y 7,5% en la tercera semana. Se presentaron principalmente en sacro y en estados I y II. El rango de los puntajes en la Escala de Braden oscilo entre 6 y 23. El percentil 25 en todas las evaluaciones estuvo entre 15 y 16 puntos, y el percentil 75 en 21. Las variaciones de los puntajes entre las tres evaluaciones fueron minimas. Las Curvas Operantes de Receptor (COR) derivadas de los datos muestran que un puntaje de 16 produce un punto de corte optimo donde simultaneamente se maximiza la sensibilidad a 85,4% y la especificidad a 63,2% con un VPP de 12,5 en ese punto y un VPN de 98,6. Conclusiones Este estudio permite concluir que en ancianos hospitalizados la escala de Braden para predecir riesgo de UP es confiable y valida, con un punto de corte de 16. Ademas sugiere que se deben tener en cuenta otros factores que afectan su validez como la edad y el estado funcional.

Cortisol and physical performance in older populations: Findings from the international mobility in aging study (IMIAS)

OBJECTIVE To compare diurnal cortisol profiles across samples of older adults from diverse populations and to examine if differences in circadian cortisol secretion are associated with poor physical performance (SPPB<9). METHODS Data were collected during the baseline survey of the International Mobility in Aging Study conducted in 2012 in Kingston (Canada), Saint-Hyacinthe (Canada), Tirana (Albania) and Manizales (Colombia). Salivary cortisol was collected from a subsample of 309 participants instructed to collect saliva on two consecutive days, and 5 different intervals each day: upon awakening (M1), 30min (M2) and 60min after awakening, at 15:00h and before bedtime (E). Cortisol was analyzed using enzyme immunoassay kits. Physical performance was measured by the Short Physical Performance Battery (SPPB). Mixed linear models were fit to assess the associations between cortisol diurnal output and physical performance, adjusting for potential confounders. RESULTS Kingston, Saint-Hyacinthe and Tirana residents had significantly higher cortisol values than their Manizales counterparts, with the population from Tirana showing the highest levels. Attenuated morning cortisol peak (M2) (p=0.025), higher cortisol bed time (E) (p=0.005), and lower M2/E ratio (p<0.001) were found among those with SPPB<9 compared with those with good physical performance (SPPB≥9). These results were not altered after adjustment by potential confounders. CONCLUSION Cortisol profiles varied across four diverse populations of older adults. Circadian cortisol secretion is associated with physical performance as an attenuated morning response and higher bed time values were observed in older adults with SPPB<9.

Model-based recursive partitioning to identify risk clusters for metabolic syndrome and its components: findings from the International Mobility in Aging Study

Objective Conceptual models underpinning much epidemiological research on ageing acknowledge that environmental, social and biological systems interact to influence health outcomes. Recursive partitioning is a data-driven approach that allows for concurrent exploration of distinct mixtures, or clusters, of individuals that have a particular outcome. Our aim is to use recursive partitioning to examine risk clusters for metabolic syndrome (MetS) and its components, in order to identify vulnerable populations. Study design Cross-sectional analysis of baseline data from a prospective longitudinal cohort called the International Mobility in Aging Study (IMIAS). Setting IMIAS includes sites from three middle-income countries—Tirana (Albania), Natal (Brazil) and Manizales (Colombia)—and two from Canada—Kingston (Ontario) and Saint-Hyacinthe (Quebec). Participants Community-dwelling male and female adults, aged 64–75 years (n=2002). Primary and secondary outcome measures We apply recursive partitioning to investigate social and behavioural risk factors for MetS and its components. Model-based recursive partitioning (MOB) was used to cluster participants into age-adjusted risk groups based on variabilities in: study site, sex, education, living arrangements, childhood adversities, adult occupation, current employment status, income, perceived income sufficiency, smoking status and weekly minutes of physical activity. Results 43% of participants had MetS. Using MOB, the primary partitioning variable was participant sex. Among women from middle-incomes sites, the predicted proportion with MetS ranged from 58% to 68%. Canadian women with limited physical activity had elevated predicted proportions of MetS (49%, 95% CI 39% to 58%). Among men, MetS ranged from 26% to 41% depending on childhood social adversity and education. Clustering for MetS components differed from the syndrome and across components. Study site was a primary partitioning variable for all components except HDL cholesterol. Sex was important for most components. Conclusion MOB is a promising technique for identifying disease risk clusters (eg, vulnerable populations) in modestly sized samples.