Are high-care nursing home residents at greater risk of unplanned hospital admission than other elderly patients when exposed to Beers potentially inappropriate medications?

AIM: To compare the risk of unplanned hospitalization in high-care nursing home residents taking Beers potentially inappropriate medications (PIM) against that of other elderly.
METHODS: Using an enhanced case-time-control design and conditional logistic regression applied to the pharmaceutical claims and other linked data of 245436 Western Australians aged ≥ 65 years (1993-2005), the study derived odds ratios for unplanned hospitalization in each group, from which attributable fractions, numbers, proportions and rates of PIM-related admissions were derived.
RESULTS: Overall, 383150 unplanned hospitalizations were identified. PIM exposure was associated with a similar proportional increase in unplanned hospitalizations in high-care nursing home residents as in other older people; adjusted OR 1.21 (95% CI 1.10-1.34; attributable fraction 17.5%) versus OR 1.19 (95% CI 1.16-1.21; attributable fraction 15.7%). However, high-care nursing home residents had much higher estimated rates of hospitalizations attributed to Beers medications than other elderly (3951 vs 1394 per 100000 person-years). The relative risk of unplanned hospitalization rose similarly in both groups with increasing numbers of different PIM taken (OR 5.1 for 10 vs 0 PIM), but was affected more markedly by 3-month PIM consumption in nursing home residents (OR 4.85, 95% CI 2.40-9.83 for 900 vs 0 PIM daily doses) than in other older adults (OR 2.10, 95% CI 1.73-2.55).
CONCLUSIONS: High-care nursing home residents do not appear to have a greater relative risk of unplanned hospitalization when given PIM, but do incur a higher absolute burden than other older adults. Physicians should exert caution with Beers medications in all older patients, restricting the number of different PIM and PIM quantity prescribed whenever possible.