Distinct body mass index trajectories to young-adulthood obesity and their different cardiometabolic consequences

Objective:

Different body mass index (BMI) trajectories that result in obesity may have diverse health consequences, yet this heterogeneity is poorly understood. We aimed to identify distinct classes of individuals who share similar BMI trajectories and examine associations with cardiometabolic health.

Approach and Results:

Using data on 3549 participants in ALSPAC (Avon Longitudinal Study of Parents and Children), a growth mixture model was developed to capture heterogeneity in BMI trajectories between 7.5 and 24.5 years. Differences between identified classes in height growth curves, body composition trajectories, early-life characteristics, and a panel of cardiometabolic health measures at 24.5 years were investigated. The best mixture model had 6 classes. There were 2 normal-weight classes: normal weight (nonlinear; 35% of sample) and normal weight (linear; 21%). Two classes resulted in young-adulthood overweight: normal weight increasing to overweight (18%) and normal weight or overweight (16%). Two classes resulted in young-adulthood obesity: normal weight increasing to obesity (6%) and overweight or obesity (4%). The normal-weight-increasing-to-overweight class had more unfavorable levels of trunk fat, blood pressure, insulin, HDL (high-density lipoprotein) cholesterol, left ventricular mass, and E/e′ ratio compared with the always-normal-weight-or-overweight class, despite the average BMI trajectories for both classes converging at ≈26 kg/m² at 24.5 years. Similarly, the normal-weight-increasing-to-obesity class had a worse cardiometabolic profile than the always-overweight-or-obese class.

Conclusions:

Individuals with high and stable BMI across childhood may have lower cardiometabolic disease risk than individuals who do not become overweight or obese until late adolescence.