Abstract P526: Associations of Body Mass Index Variability From Childhood and Midlife Class II and Class III Obesity

Background: Short periods of weight loss followed by weight gain (BMI variability) has been linked to adverse cardiovascular outcomes in adults. However, less is known about the effect of long-term BMI variability from childhood on midlife class II and class III obesity. We identified this effect in a cohort of Black and White midlife adults living in a rural community. Methods: We studied 1,268 midlife participants of the Bogalusa Heart Study (age at baseline 9.5 ± 3.5 years, age at midlife 48.2 ± 5.2 years, 59.5% women, 34.4% Black) with ≥4 measurements of BMI and other traditional cardiovascular risk factors (CVRF) from childhood. Long-term BMI variability was computed as deviation from age-predicted values (DEV). Logistic regression, adjusting for age, sex, race, CVRF, depression, alcohol use, education, and employment status, was conducted to assess associations between long-term BMI variability and midlife obesity (class II and III, BMI ≥35kg/m 2 and ≥40kg/m 2 , respectively). Interactions between race, sex and long-term BMI variability were assessed. Results: Prevalence of midlife class II and class III obesity were 26.81%(n=340) and 12.7%(n=161), respectively. DEV was positively significantly associated with having midlife class II and class III obesity. For class II obesity, no significant interactions between DEV and race or sex were observed. For class III obesity, interactions of DEV with race and sex were significant; the odds of having class III midlife obesity per unit increase in DEV were greater in White participants and in men compared with Black participants and women(see Table 1). Conclusions: We identified associations between long-term BMI variability from childhood and midlife obesity. Race and sex were observed to modify the effect of BMI variability on having midlife obesity. Further studies are needed to elucidate the role of long-term BMI variability as a predictor for increased risk of midlife obesity.