The association between personal income and aging: A population-based 13-year longitudinal study.

INTRODUCTION: Population aging is set to increase the elder dependency ratio, causing a rapid increase in healthcare expenditures and financial burden on the government. This study aims to construct an aging score from age-related diseases and to perform longitudinal analyses to examine the association between personal income and aging.

METHODS: A total of 86,838 subjects drawn from a community with 384,617 residents in northern Taiwan were examined. Personal income and aging-related diseases were measured from the National Health Insurance database during 1997-2010. Multiple linear regression and stratified analyses were used.

RESULTS: Our results indicate that subjects with low personal income (defined as monthly income ≤610 USD) can have high aging scores as calculated by selected aging-related diseases. In stratified analyses, moreover, subjects with low personal income tended to have higher aging scores across different anthropometric groups. The association was particularly evident in subjects >60years old, and they were noted across multiple strata, including those of catastrophic illness as well as type of primary care setting.

CONCLUSIONS: This study found evidence for association between low income and aging in a population with compulsory health insurance program, where accessibility barriers were low in terms of health care resources and personal socioeconomic status. The economic inequity causes difference in aging process, which deserves for future interventions.