Cognitive impairment, chronic disease burden, and functional disability: A population study of older Italians

Objective: To evaluate associations of cognitive impairment and disease burden with disability in an elderly population. Methods: The Mini-Cog was used as a cognitive screen in a population-based survey of health and functional status of 2,192 randomly selected older adults ( age 65 + years) in 11 regions of Italy. Associations of cognitive and disease measures with functional outcomes were calculated using hierarchical logistic regressions including age, Mini-Cog score, disease burden, age, education, and geographic region. Statistical significance was assigned at p < 0.01. Results: Mini-Cog scores were related to all functional indicators ( activities of daily living [ADLs], social activities, exercise, telephone and face-to-face conversation, urinary control, and ability to read the newspaper) as well as stroke, falls, and dementia diagnoses. In univariate analyses, low education was associated with Mini-Cog scores, disease burden, and disability. However, in logistic regressions, Mini-Cog score and disease burden, but not education, remained significant predictors of all basic ADLs and most higher-order functions. Functional disability was best predicted by a Mini-Cog cutoff score of 1 out of 5. Overall, although both are significant, the impact of cognitive impairment on basic ADL impairment was over four times greater than that of disease burden ( accounting for 14% versus 3% of variance). Conclusion: Cognitive impairment assessed by the Mini-Cog is a more powerful predictor of impaired ADLs than disease burden in older adults. The association of education with Mini-Cog score did not bias its ability to predict functional status. Results suggest that the Mini-Cog could be useful in assessing older population assistance needs.