Sex differences in the associations between birthweight and lipid levels in middle-age: findings from the 1958 British birth cohort.

OBJECTIVE: To examine sex differences in birthweight-lipid associations. METHODS AND
RESULTS: Using prospectively collected data on birthweight and non-fasting lipid levels at age 44-45 y from the 1958 British birth cohort (3603 men and 3583 women), sex differences in birthweight-lipid associations were examined. There were inverse associations between birthweight and total and low-density-lipoprotein (LDL)-cholesterol among women (a 1 kg increase in birthweight was associated with a 0.13 mmol/L reduction in total cholesterol (p<0.001) and a 0.07 mmol/L reduction in LDL-cholesterol (p=0.02)) but no associations among men (p=0.005 and p=0.01, respectively, for birthweight x sex interactions). There was an inverse association between birthweight and triglycerides of a similar magnitude in both sexes (a 1 kg increase in birthweight was associated with a 7% reduction in triglyceride levels in sex-adjusted models (p<0.001)). There was no association between birthweight and high-density-lipoprotein-cholesterol. Associations were largely unaltered after adjustment for covariates. Of birthweight, current height and BMI, the latter was the strongest predictor of lipid levels.
CONCLUSIONS: The finding of an inverse association between birthweight and triglycerides in both sexes and of inverse associations between birthweight and total and LDL-cholesterol only in women suggests that the mechanisms underlying the associations with birthweight may vary for different lipids.