Influence of the cognitive impairment level on the performance of the Timed "Up & Go" Test (TUG) in elderly institutionalized people.

The purpose of this study was to determine clinical variables influence (comorbid medical condition, functional independence, depressive and neuropsychiatric symptoms) on the performance of the TUG, taking into account the level of cognitive impairment in elderly institutionalized people. A cross-sectional analysis of 405 sedentary older adults living in rural home care facilities was carried out. All the participants performed the TUG and the Mini Mental State Examination (MMSE). Those who were screened positive for cognitive impairment carried out a battery of specific test aimed to assess their functional independence (Katz Index (KI)), memory function (Fuld Object Memory Evaluation (FOME)), depressive symptoms (Cornell Scale) and neuropsychiatric disturbances (Neuropsychiatric Inventory (NPI)). Applying multiple linear regression, TUG was associated with age (β=0.161, p<0.001), MMSE (β=-0.013, p<0.001) and KI (β=0.621, p<0.001). According to the defined regression model, it was noticed that the higher the level of cognitive impairment, the lower the adjustment of the model (R(2)=0.593; R(2)=0.493; R(2)=0.478). In conclusion, it seems that the performance of the TUG in institutionalized elderly people who screened positive for dementia, is mainly influenced by their functional independence and their age. Comorbid medical condition, depressive and neuropsychiatric symptoms do not seem to show any association, regardless of the level of cognitive impairment.