To critically review published articles that have examined the relationship between medication use and functional status decline in the elderly.
The MEDLINE and EMBASE databases were searched for English-language articles published from January 1986 to December 2010. Search terms included aged, humans, drug utilization, polypharmacy, inappropriate prescribing, anticholinergics, psychotropics, antihypertensives, drug burden index, functional status, function change or decline, activities of daily living, gait, mobility limitation, and disability. A manual search of the reference lists of the identified articles and the authors’ article files, book chapters, and recent reviews was conducted to retrieve additional publications. Only articles that used rigorous observational or interventional designs were included. Cross-sectional studies and case series were excluded from this review.
Nineteenstudies met the inclusion criteria. Five studies addressed the impact of suboptimal prescribing on function, three of which found an increased risk of worse function in community-dwelling subjects receiving polypharmacy. Three of the four studies that assessed benzodiazepine use and functional status decline found a statistically significant association. One cohort study identified no relationship between antidepressant use and functional status while a randomized trial found that amitriptyline, but not desipramine or paroxetine, impaired certain measures of gait. Two studies found that increasing anticholinergic burden was associated with worse functional status. In a study of hospitalized rehabilitation patients, users of hypnotics/anxiolytics (e.g., phenobarbital, zolpidem) had lower relative Functional Independence Measure motor gains than nonusers. Use of multiple central nervous system (CNS) drugs (using different definitions) was linked to greater declines in self-reported mobility and Short Physical Performance Battery (SPPB) scores in two community-based studies. Another study of nursing home patients did not report a significant decline in SPPB scores in those taking multiple CNS drugs. Finally, two studies found mixed effects between antihypertensive use and functional status in the elderly.
Benzodiazepines and anticholinergics have been consistently associated with impairments in functional status in the elderly. The relationships between suboptimal prescribing, antidepressants, and antihypertensives and functional status decline were mixed. Further research using established measures and methods is needed to better describe the impact of medication use on functional status in older adults.
Keywords: drug utilization, activities of daily living, aged