Male sex and poverty predict abrupt health decline: Deficit accumulation patterns and trajectories in the KORA-Age cohort study

Abstract

Ageing individuals differ both in their deficit accumulation (DA) trajectories and resulting DA patterns (improvement, stability, gradual or abrupt decline). This heterogeneity is still incompletely understood. The objectives of this study were thus to identify determinants of DA trajectories and DA patterns in people aged 65 and older. Data originates from the 2009 baseline assessment and 2012 follow-up of the KORA (Cooperative Health Research in the Region of Augsburg)-Age study from Southern Germany. DA was measured with a Frailty Index (FI). The effects of socio-demographic, socio-economic and lifestyle factors were analyzed using generalized linear mixed models and multinomial regressions. FI scores were available for 1076 participants at baseline (mean age 76years, 50% female) and 808 participants at follow-up. Higher baseline FI levels were significantly associated with higher age, female sex, lower physical activity, moderate alcohol consumption and obesity. Longitudinal increase in FI levels over 3years was 31% (CL: [-3%; 77%]) independent of all examined predictors. The most frequent DA patterns were stability (59%) and gradual decline (30%). Compared to stability, higher age, male sex and low income predicted (mostly fatal) abrupt decline. In conclusion, several factors are associated with FI levels at baseline whereas the change in FI levels over time seems hardly modifiable. Thus, future research should investigate if the same factors predicting older-age FI levels constitute predictors of DA onset earlier in life. Towards the end of life, being male with low income may increase the risk for abrupt decline, indicating need for early detection.

Keywords: Aged; Ageing; Epidemiologic factors; Health status; Longitudinal studies; Models; Social determinants of health; Statistical.