Timing and risk factors for functional changes associated with medical hospitalization in older patients.

BACKGROUND: Older medical patients often experience a decline in function associated with hospitalization. Some of this decline is already established at hospital admission, whereas some occurs during hospitalization. Objectives of this study were to separately describe pre-hospital and in-hospital functional changes in older Australian medical patients and to identify risk factors associated with these functional changes.
METHODS: Secondary analysis of data from a prospective controlled trial conducted in general medical units of an Australian tertiary teaching hospital. Participants were 615 consecutive patients aged 65 years or older admitted under a general medical unit for more than 2 days, discharged alive, and not fully dependent at pre-admission baseline. Activities of daily living measured 2 weeks before admission, at admission, and at discharge were used to calculate rates of pre-hospital and in-hospital decline and of in-hospital recovery to pre-admission function. Potential predictors including age, sex, diagnosis, illness severity, pre-admission function, pre-admission supports, and documented "geriatric syndromes" (dementia, falls, malnutrition) were investigated for each functional change outcome using multiple logistic regression models.
RESULTS: Sixty-four percent of participants had pre-hospital functional decline; only 42% of these had recovered to pre-admission function by hospital discharge. Only 7% had in-hospital decline. The different functional change variables had distinct patterns of predictors.
CONCLUSIONS: Most decline occurred prior to hospitalization and was associated with common indicators of poor outcomes in hospitalized elders. In-hospital decline was uncommon, suggesting that in-hospital recovery may be a more appropriate intervention target.