Activity, adiposity and weight change in Jamaican adults / Actividad, adiposidad y cambio de peso en los adultos jamaicanos

OBJECTIVE: Populations in developing countries are particularly vulnerable to the development of obesity in the period of rapid transition to a more modernized lifestyle. We sought to determine the relationship between activity energy expenditure (AEE), adiposity and weight change in an adult population undergoing rapid socio-economic transition. METHODS: Total daily energy expenditure (TDEE) was measured using the doubly labelled water method, resting energy expenditure (REE) using indirect calorimetry and AEE calculated as the difference between TDEE and REE, in adults from a working class community in Spanish Town, Jamaica. During six years of follow-up, weight was measured between one and four times. Mixed effects regression modelling was used to test for association between components of the energy budget and weight change. RESULTS: Men (n = 17) weighed more but women (n = 18), had significantly more body fat, 38.5% vs 24.5%, respectively (p < 0.01). Men had higher levels of EE, particularly AEE after adjustment for body weight, 66.3 versus 46.4 kJ/kg.d for men and women, respectively (p < 0.001). At baseline, adjusted AEE was inversely associated with body fat in men and women, r = -0.46 and r = -0.48, respectively (p < 0.05). Mean rate of weight change was + 1.1 and + 1.2 kg/year for men and women, respectively. No component of EE, ie TDEE, REE or AEE, significantly predicted weight change in this small sample. CONCLUSIONS: These results suggest an important role for AEE in maintaining low levels of adiposity. The lack of association between EE and weight change, however, suggests populations in transition are at risk of obesity from environmental factors (eg dietary) other than simply declining physical activity levels.

OBJETIVO: Las poblaciones en los países en vía de desarrollo son particularmente vulnerables al desarrollo de la obesidad en el período de rápida transición a un estilo de vida más moderno. Buscamos determinar la relación entre el gasto energético por actividad (GEA), la adiposidad y el cambio de peso en una población adulta en proceso de rápida transición socio-económica. MÉTODOS: El gasto energético total diario (GETD) fue medido usando el método del agua doblemente marcada, gasto energético en reposo (GER) usando calorimetría indirecta y el GEA calculado como la diferencia entre GETD y GER, en adultos de una comunidad de clase obrera en Spanish Town, Jamaica. Durante seis años de seguimiento, el peso fue medido entre una y cuatro veces. Un modelo de regresión de efectos mixtos fue usado para probar la asociaciF3n entre los componentes del presupuesto de la energEDa y el cambio de peso. RESULTADOS: Los hombres (n = 17) pesaron más pero las mujeres (n = 18) teníEDan significativamente más grasa corporal, 38.5% frente a 24.5%, respectivamente (p < 0.01). Los hombres tenían niveles más altos de GE, particularmente GEA después del ajuste por peso corporal, 66.3 frente a 46.4 kJ/kg.d para los hombres y mujeres, respectivamente (p < 0.001). Al inicio, el GEA ajustado estaba inversamente asociado con la grasa del cuerpo en los hombres y mujeres, r = -0.46 y r = -0.48, respectivamente (p < 0.05). La tasa media de cambio de peso fue +1.1 y +1.2 kg/ano para los hombres y mujeres, respectivamente. Ningún componente de GE, es decir, GETD, GER o GEA, predijo significativamente el cambio de peso en esta muestra pequeña. CONCLUSIONES: Estos resultados sugieren un papel importante del GEA en cuanto a mantener niveles bajos de adiposidad. Sin embargo, la falta de asociación entre GE y cambio de peso, sugiere que las poblaciones en transición corren el riesgo de obesidad debido a factores ambientales (p.ej. dietéticos) distintos de la mera...

Features of isolated post-challenge hyperglycaemia in Jamaican adults

Isolated post-challenge hyperglycaemia (IPH) can be defined as a two-hour plasma glucose concentration > or = 11.1 mmol/L with a fasting plasma glucose concentration < 7.0 mmol/L. The aim of this prospective study was to determine the prevalence of IPH in a cohort of Jamaican individuals, and to determine if simple clinical features may predict the presence and subsequent diagnosis of IPH. A cohort of 1694 adults aged 25-74 years without physician-diagnosed diabetes mellitus was randomly selected. An oral glucose tolerance test (OGTT) was performed. Anthropometry, blood pressure and lipid profiles were measured. The prevalence of undiagnosed diabetes mellitus by the 1999 World Health Organization criteria was 6.4. IPH accounted for 24 of these cases and 1.4 of the entire population. Individuals with IPH were significantly older, with greater body mass index, waist-hip ratio, systolic blood pressure, fasting blood glucose, total cholesterol and LDL-cholesterol than individuals with normal glucose tolerance. Individuals with IPH were not significantly different from individuals with fasting plasma glucose levels > or = 7 mmol/L (i.e. fasting hyperglycaemia) in anthropometry or blood pressure. However, total cholesterol and LDL-C were significantly elevated in the IPH group. OGTT screening of individuals with impaired fasting glucose (i.e. 6.1-6.9 mmol/l) could reduce the IPH group by 50. Reducing the threshold for fasting glucose to 5.6 mmol/L would correctly classify 87 of the population. We concluded that individuals with IPH have features of the metabolic syndrome, which can aid in selection for screening. OGTT screening of individuals with fasting glucose values of 5.6-6.9 mmol/l is needed to identify IPH