Women represent a growing proportion of all older people, but added survival means increasing disability associated with chronic conditions such as cardiovascular and respiratory disease, cancer and diabetes, and functional limitations that impact on daily living [1–4]. What is not well understood is the extent to which, apart from age, social and economic factors differently contribute to disability in older men and women. This paper analyses differences in disability prevalence between men and women aged 50 and over, using multi-country data from the World Health Survey (WHS).
Disability spans physical, mental and psychosocial functioning, encompassing a complex suite of conditions, activities and relationships [2, 5]. This study adopts the most recent definition of disability based on the International Classification of Functioning, Disability and Health (ICF) developed by the World Health Organization (WHO) . Under the ICF “disability” includes limitations in functioning resulting from interactions between the individual’s “health condition” (e.g. diseases, injuries, and disorders) and “environmental factors”. These decrements in body function and capacity are not necessarily linked to a particular health condition .
At a population level, “social determinants” or the conditions in which people are born, live, work and age, influence morbidity and mortality . Differences in health between men and women are attributed to both biological and social factors [8–12]. Social determinants contribute to gender inequalities and inequities – unfair and avoidable differences in health . In many countries age adjusted disability prevalence rates are higher for women and those in the poorest wealth quintile .
A study of gender differences in health at ages 50 and older in 11 European countries, England and the United States showed that, after adjusting for age, women were more likely than men to have disabling, non-lethal conditions including functioning problems and depressive symptoms . Socioeconomic disadvantage, measured by occupation, lower levels of income and education in higher-income countries is associated with greater disability among older women [14–16]. Evidence from studies in lower- and middle-income countries also shows association between social factors and disability in older women [10, 11, 17–20].
The aims of this study are to: identify and assess how disability in males and females aged 50 and older is separately associated with a range of social factors; measure and evaluate the effects of sex (i.e. being male or female) on disability in people aged 50 and older after adjusting for the effects of age and the social determinants, and decompose the extent to which these different factors explain male–female differences in disability in older adults.
This study fills several gaps in the existing literature with regard to the determinants of disability in older adult populations for several reasons. Firstly the data derive from a large multi-country survey that used the same instrument and methodology to collect health and other information at the individual level across high-, middle- and low-income countries. Secondly, using an internationally agreed definition of disability based on the ICF, an advanced statistical method is applied to create a measure of disability which ensured cross country comparability. Thirdly, the study focusses specifically on the social determinants of health in men and women . Finally, we apply a decomposition method to show how age and social factors contribute to the disability difference between men and women in this large international dataset.