Multimorbidity, frailty and functional disability in octogenarians: A structural equation analysis of relationship

Path analysis allows for an understanding of the complex interrelationships between multiple variables and interactions in the octogenarians. The aim of this study was to estimate the isolated and combined prevalence of multimorbidity, frailty and functional disability and the direct and indirect association of these conditions in octogenarians. A cross-sectional study was conducted with 166 community-dwelling individuals aged 80 years or older participating in the FIBRA80+ epidemiological study. Multimorbidity was defined by three or more chronic diseases, frailty according to 3 or more components of physical frailty phenotype and functional disability as aid needed to perform one or more activities of daily living (ADLs). Associations were tested by Pearson's chi-square test; the relationship between the variables of interest and the mediating variables was tested with structural equation (path) analysis. We observed a higher prevalence of seniors with disability and multimordibity/disability. In path analysis, number of chronic diseases mediated the relation between sex and number of frailty components (p = 0.031), and these mediated the relation between number of diseases and disability (p = 0.008). The study points out the relationship between the simultaneous presence and interaction between multimorbidity, functional disability and frailty. Through path analysis, our findings provide characteristics in relation to the health-disease process, mainly mediation and interaction among octogenarians.