Lifecourse predictors of normal metabolic parameters in overweight and obese adults

Not all overweight and obese individuals appear to be at equal risk of developing metabolic abnormalities. We sought to examine the effect of factors from different stages of life on risk of metabolic abnormalities at age 50 years in overweight and obese adults.

Longitudinal study of all persons born in Newcastle upon Tyne, UK in May and June 1947 and followed to age 50 years when a clinical examination took place and a detailed questionnaire on health and lifestyle was completed. Participants in this study (n=223) were those defined as being overweight or obese with a body mass index (BMI) greater than or equal to 25 at age 50 years. Subjects were defined as 'metabolically normal' if they had normal lipids, glucose and blood pressure.

Lower BMI was the strongest predictor of remaining metabolically normal in both men and women. After adjusting for BMI, lower levels of cigarette smoking and higher levels of physical activity were independently associated with being metabolically normal in men. No other factors were independently associated with being metabolically normal in women. A stronger inverse relationship between BMI and metabolic status was found in men (Odds ratio (OR) per unit increase in BMI=0.65, 95% confidence intervals (95% CI) 0.52-0.81) than in women (OR=0.90, 95% CI 0.82-0.99). No association was seen for factors operating in fetal, infant and childhood life.

Adult factors made a greater contribution to remaining metabolically normal than birth or childhood factors in this sample of overweight and obese adults. A lower adult BMI appeared to reduce the risk in men and women and lower cigarette smoking and higher level of physical activity also independently reduced the risk in men. Public health policy to reduce the burden of morbidity associated with obesity should continue to encourage weight loss, physical activity and smoking cessation.