Trajectory classes of depressive symptoms in a community sample of older adults

To identify trajectories of depressive symptoms in older community residents.

Depressive symptomatology, based on a modified Center for Epidemiological Studies-Depression scale, was obtained at years 0, 3, 6, and 10, in the Duke Established Populations for Epidemiologic Studies of the Elderly (n = 4162). Generalized growth mixture models identified the latent class trajectories present. Baseline demographic, health, and social characteristics distinguishing the classes were identified using multinomial logistic regression.

Four latent class trajectories were identified. Class 1 - stable low depressive symptomatology (76.6% of the sample); class 2 - initially low depressive symptomatology, increasing to the subsyndromal level (10.0%); class 3 - stable high depressive symptomatology (5.4%); class 4 - high depressive symptomatology improving over 6 years before reverting somewhat (8.0%). Class 1 was younger, male gender, with better education, health, and social resources, in contrast to class 3. Class 2 had poorer cognitive functioning and higher death rate. Class 4 had better health and social resources.

Reduction in high depressive symptomatology is associated with more education, better health, fewer stressful events, and a larger social network. Increasing depressive symptomatology is accompanied by poorer physical and cognitive health, more stressful life events, and greater risk of death.