An epidemiological study of self-care restriction and joint pain in older people [PhD Thesis]

Self-care restriction is proposed in the World Health Organization’s International Classification of Functioning (ICF) as an important functional consequence of health conditions. In contrast to traditional approaches which focus only on an individual’s physical capacity, the ICF model also acknowledges the potential role of contextual factors such as environmental factors and personal needs. This thesis aims to understand the occurrence, course, and determinants of self-care restriction, as defined in the ICF, in community-dwelling adults aged 50 years and over, particularly in relation to joint pain and from a novel perspective: person-perceived participation restriction in which individuals judge whether their self-care needs are met “as and when I have wanted”. Data collected at three time points, by postal questionnaire across 6 years in the North Staffordshire Osteoarthritis project, were used in the analysis (n=7725 at baseline). The prevalence of person-perceived restricted self-care was 11.5% (95% CI 10.8, 12.2). A parsimonious model of factors associated with self-care restriction included age, activity limitation, depression, cognitive impairment, perceived inadequacy of income and low educational attainment. Older adults with joint pain were more likely to report self-care restriction, although this association was not independent of other factors. The frequencies of onset and persistence of restricted self-care at three years were 6.6% (95% CI 5.9, 7.5) and 38.9% (95% CI 33.7, 44.3) respectively. The key factors associated with restricted self-care at baseline were also predictive of the onset of self-care restriction at three years, but only depression was predictive of persistence. Unmet need for help and assistance was associated with restricted self-care in older adults with joint pain. However, those who received help were also more likely to report restriction. These analyses suggest a range of potential health and social targets for reducing self-care restriction in individuals with joint pain in middle and old age.