Depression moderates the frailty-subjective health relationship among centenarians

Abstract

The correspondence between subjective health and objective indicators of health (e.g., physical functions) often wanes as people get older. Multiple models have proposed the role of psychosocial characteristics in moderating the subjective-objective health correspondence. This paper adds to the current understanding of subjective health in advanced age by examining the moderation effect of depression on the frailty-subjective health association. Cross-sectional data analysis was conducted on 153 Chinese near- and centenarians of Hong Kong Centenarian Study. Frailty was measured as a composite of fatigue, low resistance, low aerobic activities, presence of 5 or more chronic illnesses, and unintended weight loss. Depression was measured by the Geriatric Depression Scale-Short Form (GDS-SF). Subjective health was assessed using a 5-point scale running from 1 (very poor) to 5 (very good). 19.6% of the sample was regarded as non-frail, 56.2% was pre-frail, and 24.2% was frail. Mean scores (SD) for GDS-SF and subjective health were 2.6 (3.7) and 3.3 (0.9) respectively. Hierarchical multiple regressions were used to investigate the moderation effect after controlling for demographic variables. Results show that living with family, favorable socio-economic status, and lower level of frailty were significant independent predictors of subjective health. More important, fewer depressive symptoms, but not a lower level of lethargy, were associated with a weaker frailty-subjective health relationship. Our results imply a protective psychological mechanism that enables elderly to counter the deleterious effect of functional limitations on subjective health. We call for future studies to explore the role of psychosocial capital in coping with functional limitations.