Birth weight, childhood growth and abdominal obesity in adult life.

Objective: To examine the relationship of adult abdominal obesity to birth weight, childhood growth and lifetime socioeconomic circumstances.

Methods: A cohort of 3200 men and women with measured waist and hip circumference, height and weight at age 43 who have been followed since their birth in March 1946 in England, Scotland and Wales. Regression models were used to examine mean waist-hip ratio and waist circumference in relation to prospective measures of birth weight, weight relative to height in childhood at ages 4, 7, 11 and 15 and adult body mass index, and to test the independent and interactive nature of the associations and adjust for childhood and adult social class.

Results: There was a small inverse effect of birth weight on waist-hip ratio (P=0.037) but not waist circumference in women, after adjustment for current body size. Relative weight at age 7 was inversely related to waist-hip ratio and waist circumference in men (P<0.001 for both) and waist circumference in women (P=0.007) after adjustment for current body size. These relationships were attenuated in men of large body mass index (P<0.01 for interactions between relative weight at 7 y and body mass index in both cases) but were not modified by birth weight. Relative weights at other ages showed similar patterns to those observed at age 7, the effect being weakest at age 4. These findings were independent of lifetime socioeconomic circumstances.

Conclusion: This study found a small prenatal inverse effect of fetal growth on adult waist-hip ratio due to a reduced hip size. There was also an inverse postnatal effect of childhood growth such that for any given adult body size those who had been lighter in childhood were more at risk of abdominal obesity. These relationships were independent of childhood socioeconomic circumstances and support the idea that insulin resistance may be linked to low weight in childhood.