Drug Burden Index associated with function in community-dwelling older people in Finland: a cross-sectional study

Background. This cross-sectional study aimed to investigate the relationship between exposure to anticholinergic and sedative medications, measured with the Drug Burden Index (DBI), and functional outcomes in community-dwelling older people living in Finland. 

Methods. The study population consisted of community-dwelling older people (n 700) enrolled in the Geriatric Multidisciplinary Strategy for the Good Care of the Elderly (GeMS) study. Outcomes included walking speed, chair stands test, grip strength, timed up and go (TUG) test, instrumental activities of daily living (IADL), and Barthel Index. 

Results. Exposure to DBI drugs was identified in 37% of participants: 24% had a DBI range between >0 <1, and 13% DBI ≥1. After adjusting for confounders, exposure to DBI drugs was associated with slower walking speed (P < 0.0001), poorer performance on chair stands (P 0.0001) and TUG (P < 0.0001), difficulties in IADL (P < 0.0001), and Barthel Index (P < 0.0001). The mean adjusted walking speed, time to complete chair stands and TUG, IADL, and Barthel scores were significantly poorer among participants with higher DBI ranges. 

Conclusion. In older adults living in Finland, DBI was associated with impaired function on previously tested and new outcomes. This finding supports the use of the DBI as tool, in combination with other assessments, to identify older people at risk of functional impairment. The findings highlight the need for revision of current guidelines to improve the quality of drug use in older people.