[Socioeconomic inequalities in the onset and progression of disability in a cohort of older people in Santiago (Chile)]

Abstract

Objective: To describe and compare socioeconomic inequalities in the onset and progression of disability in a cohort of Chilean community-dwelling older people that provides unprecedented information about this process in Chile.

Methods: The data were drawn from a 10-year longitudinal study (2000-2010) that followed a probabilistic and representative sample of the SABE (Health, Welfare and Aging) cohort. The present study was based on 78% (1019) of the baseline sample of adults aged 60 years or more living in Santiago, Chile. Functional limitation was defined on the basis of a combination of six basic activities of daily living, seven instrumental activities, and seven mobility activities (limited, no limited). Socioeconomic position (high, medium and low) was assessed by combining measures of household equipment, wealth, and education.

Results: The initial prevalence of functional limitation was 47.3% (95%CI: 44.2-50.4) with a clear socioeconomic gradient (60.1% low, 47.5% medium, and 28.7% high; p<0.001). At the end of the follow-up, older adults with low socioeconomic status remained functionally limited while those with high socioeconomic status remained non-limited. The incidence density of functional limitation also followed a socioeconomic gradient (5.33, 6.59 and 7.73 per 100 years-person for low, medium and high socioeconomic status). Social inequalities were also observed for mortality.

Conclusion: This study corroborates the social stratification of functional status and mortality, suggesting that aging is not a leveler of inequalities. In Latin-American countries, policies should aim to reduce inequalities by attempting to limit exposure to risk factors and to compensate for deficiencies (especially among the poorest older people) in order to prevent the progression of functional impairment to disability.