Group-Based Trajectory of Body Shape From Ages 5 to 55 Years and Cardiometabolic Disease Risk in 2 US Cohorts

Abstract

The association of adiposity across the life span with cardiometabolic risk is not completely delineated. We used a group-based modeling approach to identify distinct trajectories of body shape from ages 5 years to 55 years among 84,792 women from the Nurses' Health Study (1976-2010) and 37,706 men from the Health Professionals Follow-up Study (1986-2010) and assessed the associations between these trajectories and incidence of type 2 diabetes and cardiovascular disease (CVD) during a 17-year follow-up period. Compared with those who maintained leanness throughout the life span ("lean-stable" trajectory), participants who maintained a medium body shape ("medium-stable" trajectory) had somewhat increased risk. Those who started lean but had a moderate or marked increase in adiposity ("lean-moderate increase" and "lean-marked increase" trajectories) had even higher risk (e.g., for a "lean-marked increase" trajectory, the hazard ratio for diabetes was 8.11 (95% confidence interval (95% CI): 7.10, 9.27) in women and 2.36 (95% CI: 2.04, 2.74) in men; for CVD, it was 1.38 (95% CI: 1.25, 1.52) in women and 1.28 (95% CI: 1.16, 1.41) in men). Participants who started heavy and became heavier (a "heavy-increase" trajectory) had substantially elevated risk (for diabetes, the hazard ratio was 7.34 (95% CI: 6.40, 8.42) in women and 2.80 (95% CI: 2.37, 3.31) in men; for CVD, it was 1.55 (95% CI: 1.40, 1.71) in women and 1.35 (95% CI: 1.20, 1.53) in men). Our data showed that trajectories of body shape from ages 5 to 55 years were associated with subsequent risk of developing type 2 diabetes and CVD.

Keywords: adiposity; cardiovascular diseases; diabetes mellitus; obesity.

Figure 1.

Figure drawing used to assess body shape at ages 5, 10, 20, 30, and 40 years among women from the Nurses’ Health Study (1988) (A) and men from the Health Professionals Follow-up Study (1988) (B). (Reproduced from Stunkard et al. (21) with permission from Lippincott Williams & Wilkins, Philadelphia, Pennsylvania).

Figure 2.

Trajectories of body shape by age among women from the Nurses’ Health Study (1976–2010) (A) and men from the Health Professionals Follow-up Study (1986–2010) (B). We identified distinct trajectories of body fatness across the life span using a group-based modeling approach. In 1988, participants in both cohorts were asked to recall their body shapes in early and middle life by choosing one of 9 pictorial body diagrams (Figure 1) that best depicted their body outline at ages 5, 10, 20, 30, and 40 years. We calculated body mass index (weight (kg)/height (m)²) at ages 50 and 55 years and then converted body mass index to the same scale as that used at younger ages. Participants included prevalent cases of cancer, cardiovascular disease, and diabetes at age 55 years.