BackgroundSocioeconomic status has been operationalised in a variety of ways, most commonly as education, social class, or income. In this study, we also use occupational complexity and a SES-index as alternative measures of socioeconomic status. Studies show that in analyses of health inequalities in the general population, the choice of indicators influence the magnitude of the observed inequalities. Less is known about the influence of indicator choice in studies of older adults. The aim of this study is twofold: i) to analyse the impact of the choice of socioeconomic status indicator on the observed health inequalities among older adults, ii) to explore whether different indicators of socioeconomic status are independently associated with health in old age.MethodsWe combined data from two nationally representative Swedish surveys, providing more than 20 years of follow-up. Average marginal effects were estimated to compare the association between the five indicators of SES, and three late-life health outcomes: mobility limitations, limitations in activities of daily living (ADL), and psychological distress.ResultsAll socioeconomic status indicators were associated with late-life health; there were only minor differences in the effect sizes. Income was most strongly associated to all indicators of late-life health, the associations remained statistically significant when adjusting for the other indicators. In the fully adjusted models, education contributed to the model fits with 0–3% (depending on the outcome), social class with 0–1%, occupational complexity with 1–8%, and income with 3–18%.ConclusionsOur results indicate overlapping properties between socioeconomic status indicators in relation to late-life health. However, income is associated to late-life health independently of all other variables. Moreover, income did not perform substantially worse than the composite SES-index in capturing health variation. Thus, if the primary objective of including an indicator of socioeconomic status is to adjust the model for socioeconomic differences in late-life health rather than to analyse these inequalities per se, income may be the preferable indicator. If, on the other hand, the primary objective of a study is to analyse specific aspects of health inequalities, or the mechanisms that drive health inequalities, then the choice of indicator should be theoretically guided.Electronic supplementary materialThe online version of this article (10.1186/s12939-017-0670-3) contains supplementary material, which is available to authorized users.

This suggests the importance of childhood living conditions in maintaining cognitive function even in late life.

Background: The global number of centenarians is still strongly growing and information about the health and healthcare needs of this segment of the population is needed. This study aimed to estimate the prevalence of frailty among centenarians included in a multinational study and to investigate associated factors. Methods: The 5-COOP study is a cross-sectional survey including 1,253 centenarians in 5 countries (Japan, France, Switzerland, Denmark, and Sweden). Data were collected using a standardized questionnaire during a face-to-face interview (73.3%), telephone interview (14.5%), or by postal questionnaire (12.2%). The 5 dimensions of the frailty phenotype (weight loss, fatigue, weakness, slow walking speed, and low level of physical activity) were assessed by using self-reported data. Factors associated with frailty criteria were investigated by using multivariate regression models. Results: Almost 95% of the participants had at least 1 frailty criterion. The overall prevalence of frailty (3 criteria or more) was 64.7% (from 51.5% in Sweden to 77.6% in Switzerland), and 32.2% of the participants had 4 or 5 criteria. The most frequent criteria were weakness (84.2%), slow walking speed (77.6%), and low level of physical activity (72.5%), followed by fatigue (43.8%) and weight loss (23.8%). Factors associated with frailty included data collection modes, country of residence, gender, living in institution, depression, dementia, disability, falls, and sensory impairments. Conclusions: This study shows that reaching 100 years of age rarely goes without frailty and sheds light on factors associated with frailty at a very old age.