Dementia and loss of functional autonomy in the elderly

Aim: To determine the role played by dementia in the loss of functional autonomy in elderly patients, in terms of progression and recovery, through several stages of increasing disability. Method: Study data were derived from 13 years of follow-up in the PAQUID (Elderly Persons quid ), cohort which at baseline included 3 777 community dwellers aged 65 and over who lived at home in the Gironde and Dordogne regions in Southwestern France. Functional autonomy was assessed by studying their disability in basic Activities of Daily Living (ADL), Instrumental ADL (IADL) and mobility restriction assessed on the Rosow-Breslau scale, combined in a four-grade hierarchical indicator. The diagnosis of dementia was confirmed by a neurologist. We used a five-state Markov model to estimate transition intensities between these four disability grades and to death. Results: A total of 579 incident-cases of dementia was observed over the 13 years of follow-up. After adjustment for age (in two categories: younger and older than 80 years), gender, educational level, place of residence, receiving assistance at home, institutionalization and the number of drugs the patients were currently taking, dementia remained strongly associated with an increase in the risk of progression to IADL disability and then to ADL disability. The process was accelerated in institutionalized participants but slower in participants with a higher educational level. Conclusion: Dementia is a major determinant of loss of functional autonomy in the elderly, independent of the modifying effects of other psychosocial factors.