Developmental trajectories of body mass index throughout the life course: An application of latent class growth (mixture) modelling

The aims of this study are 1) to analyse developmental trajectories of body fatness from adolescence into adulthood, hereby determining the number and characteristics of distinct body fatness trajectories, and 2) to relate these distinct subgroups to indicators of cardiovascular disease risk, revealing subgroups specifically at risk. Furthermore, this paper will illustrate in more detail the application of latent class growth (mixture) modelling (LCGMM) on longitudinal, observational data. Data were obtained from the Amsterdam Growth and Health Longitudinal Study, an ongoing observational study of apparently healthy participants (N=336). Participants were followed up from 13-42 years of age. Body mass index was used as a marker for body fatness and CVD-risk factors included Mean Arterial Pressure and HDL-Cholesterol. LCGMM were used for the identification of developmental trajectories of body fatness and linear regression analyses were used for the associations between the trajectories and CVD-risk. Analyses revealed three distinct trajectories; a “normative” trajectory (88.4%); a progressively overweight trajectory (4.5%); and a progressively overweight but stabilising trajectory (7.1%). Statistically significant differences in CVDrisk between these trajectories appeared. These results show that body fatness development throughout life is heterogeneous, showing differences in CVD-risk. This paper also demonstrates that LCGMM is a promising technique to distinguish between subjects with different developmental trajectories. Developmental trajectories of body mass index throughout the life course | 39