Personality and health as predictors of income decrease in old age: findings from the longitudinal SMILE study.

BACKGROUND There is much evidence for the influence of low socio-economic status on poor health. It is, however, also important to study the ways in which people attain and retain their socio-economic status and the factors that predict changes in socio-economic status, such as a decrease in income. Such mobility also occurs in older populations, in which financial and health-related changes are very common, especially after retirement. METHODS Three years of follow-up data from 1443 Dutch men and women aged 55 years and older who participated in the Study on Medical Information and Lifestyles Eindhoven (SMILE) were gathered. Logistic regression analyses were used to study the independent effects of physical and mental dysfunction and severity of chronic diseases and adverse personality factors on decrease in income. RESULTS Social anxiety (OR = 1.62, 95% CI: 1.09-2.40), physical dysfunction (OR = 1.71, 95% CI: 1.07-2.74) and severe diseases (OR = 1.37, 95% CI: 1.05-1.78) were significant predictors of decrease in income. These contributions were independent of each other, and remained robust after controlling for other confounding factors, such as gender, age and educational level and change in employment status. Mental dysfunction and other personality characteristics, such as hostility and mastery, did not contribute to decrease in income. CONCLUSION Social anxiety and poor physical health are relevant factors associated with decrease in income in old age. The findings suggest that these factors are important in retaining one's socio-economic status. Future longitudinal research is necessary to further disentangle the mechanisms and pathways related to socio-economic health inequalities along the life-course.