Kahng, S.K., R.E. Dunkle, and James S. Jackson. 2004. "The Relationship Between the Trajectory of Body Mass Index and Health Trajectory Among Older Adults - Multilevel Modeling Analyses." Research on Aging, 26:31-61.
Little is known about the cross-sectional or longitudinal relationships between body weight and health at older ages. Using multilevel modeling analyses, this study examined the trajectories of body mass index (BMI), chronic health conditions (CHC), and functional disability (FD); factors associated with the trajectories; and the relationships between the trajectories. The sample of elders aged 65 and older participated in the Americans Changing Lives longitudinal study. Participants showed decreasing BMI and increasing CHC and FD with time. Current smokers presented lower BMI at Wave I and showed a slower decrease in BMI over time than those who never smoked. Obesity was associated with more CHC and greater FD at Wave I but did not influence their changes. Elders who experienced a slower decrease in BMI showed a slower increase in CHC and FD; the change in health was not related to the change in BMI.