Childhood obesity and adult cardiovascular mortality: a 57-y follow-up study based on the Boyd Orr cohort

Few studies have examined associations between childhood overweight and adult disease. We examined the relation between BMI measured in childhood and adult all-cause and cardiovascular mortality in a 57-y follow-up of a cohort study based on the Carnegie (Boyd Orr) Survey of Family Diet and Health in prewar Britain (1937-1939). Complete baseline and follow-up data were available for 1165 males and 1234 females who were aged between 2 y and 14 y 9 mo when they were examined. All-cause and cardiovascular mortality were associated with higher childhood BMIs. Compared with those with BMIs between the 25th and 49th centiles, the hazard ratio (95% CI) for all-cause mortality in those above the 75th BMI centile for their age and sex was 1.5 (1.1, 2.2) and for ischemic heart disease it was 2.0 (1.0, 3.9). There was also a suggestion of a nonlinear association with overall mortality; those in the 25-49th centile of the BMI distribution had the lowest mortality rates. The linear associations may be due in part to the tracking of BMI between childhood and adulthood. High BMI in adults is known to be associated with raised blood pressure and abnormal lipid profiles. The relative contributions of adult and childhood overweight to the observed mortality patterns are uncertain. From the public health perspective, strategies aimed at reducing weight in childhood are important but may only affect adult health if such weight reduction persists into adulthood.