Background

Depression and disability are closely linked. Less is known regarding clinical and subclinical depressive symptoms over time and risk of disability and mortality.

Methods

Responses to the Center for Epidemiologic Studies Short Depression scale (CES-D10) were assessed over a 4-year period in men (n = 1032) and women (n = 1070) aged 70-79 years initially free from disability. Depressive symptom trajectories were defined with group-based models. Disability (2 consecutive reports of severe difficulty walking one-quarter mile or climbing 10 steps) and mortality were determined for 9 subsequent years. Hazard ratios (HRs) were estimated using Cox proportional hazards adjusted for covariates.

Results

Three trajectories were identified: persistently nondepressed (54% of men, 54% of women, mean baseline CES-D10: 1.16 and 1.46), mildly depressed and increasing (40% of men, 38% of women, mean baseline CES-D10: 3.60 and 4.35), and depressed and increasing (6% of men, 8% of women, mean baseline CES-D10: 7.44 and 9.61). Disability and mortality rates per 1,000 person years were 41.4 and 60.3 in men and 45.8 and 41.9 in women. Relative to nondepressed, men in the mildly depressed (HR = 1.45, 95% confidence interval [CI] 1.11-1.89) and depressed trajectories (HR = 2.12, 95% CI 1.33-3.38) had increased disability; women in the depressed trajectory had increased disability (HR = 2.02, 95% CI 1.37-2.96). Men in the mildly depressed (HR = 1.24, 95% CI 1.01-1.52) and depressed trajectories (HR = 1.63, 95% CI 1.10-2.41) had elevated mortality risk; women exhibited no mortality risk.

Conclusions

Trajectories of depressive symptoms without recovery may predict disability and mortality in apparently healthy older populations, thus underscoring the importance of monitoring depressive symptoms in geriatric care.

Objectives

To examine body mass index (BMI) trajectories with change in lean mass and physical function in old age.

Design

Prospective cohort study.

Setting

Health, Aging and Body Composition Study.

Participants

Black and white men (n = 482) and women (n = 516) aged 73.1 ± 2.7 and initially free of disability.

Measurements

A group-based trajectory model was used to determine BMI trajectories, the path a person's BMI followed over 9 years. Lean mass, gait speed, grip strength, and knee extension strength were assessed at baseline and after 9 years, and relative changes were calculated. Multivariable linear regression was used to determine associations between trajectories and relative change in lean mass and physical function.

Results

Four BMI trajectories were identified for men and four for women. Although all demonstrated a decline in BMI, the rate of decline differed according to trajectory for women only. Men in Trajectory 4 (mean BMI at baseline 33.9 ± 2.3 kg/m(2) ) declined more than those in Trajectory 1 (mean BMI at baseline 22.9 ± 1.6 kg/m(2) ) in gait speed (-9.91%, 95% confidence interval (CI) = -15.15% to -4.67%) and leg strength (-8.63%, 95% CI = -15.62% to -1.64%). Women in Trajectory 4 (mean BMI at baseline 34.9 ± 3.0 kg/m(2) ) had greater losses than those in Trajectory 1 (mean BMI at baseline 20.5 ± 1.6 kg/m(2) ) in lean mass in the arms (-3.19%, 95% CI = -6.16% to -0.23%). No other associations were observed.

Conclusion

Obese men had the highest risk of decline in physical function despite similar weight loss between trajectories, whereas overweight and obese women who lost the most weight had the greatest risk of lean mass loss. The weight at which a person enters old age is informative for predicting loss in lean mass and physical function, illustrating the importance of monitoring weight.