Instrumental Activities of Daily Living as a Potential Marker of Frailty: A Study of 7364 Community-Dwelling Elderly Women (the EPIDOS Study)

BACKGROUND: A number of clinical conditions have been shown to be associated with frailty in elderly people. We hypothesized that incapacities on the Instrumental Activities of Daily Living (IADLs) scale could make it possible to identify this population. We investigated the associations between IADL incapacities and the various known correlates of frailty in a cohort of community-dwelling elderly women. METHODS: Cross-sectional analysis was carried out on the data from 7364 women aged over 75 years (EPIDOS Study). The IADL was the dependent variable. Sociodemographic, medical, and psychological performance measures were obtained during an assessment visit. Falls in the previous 6 months and fear of falling were also ascertained. Body composition was measured by dual-energy x-ray absorptiometry. The factors associated with disability in at least one IADL were included in a logistic regression model. RESULTS: Thirty-two percent of the population studied had disability in at least one IADL item. This group was significantly older (81.7 +/- 4.1 yr vs 79.8 +/- 3.4 yr), had more frequent histories of heart disease, stroke, depression or diabetes, and was socially less active (p =.001). These associations persisted after multivariate analysis. Cognitive impairment as assessed by the Pfeiffer test (Pfeiffer score <8) was closely associated with disabilities on the IADL (OR 3.101, 95% confidence interval [CI] 2.19-4.38). Falls and fear of falling were also more frequent in the group of women with an abnormal IADL (p =.001) but only fear of falling remained significantly associated with incapacities on at least one IADL item after logistic regression (OR 1.47, 95% CI 1.28-1.69). Women with disability on at least one IADL item also had lower bone mineral density, this was independent of the other factors. CONCLUSION: Our results confirmed that women with disability on at least one IADL item are frailer because they had more associated disorders, poorer cognitive function and more frequent falls. Disabilities on this scale could be a good tool for identifying individuals at risk of frailty among elderly persons living at home and in apparent good health. This finding requires confirmation by longitudinal studies.