Improvements in Antibiotic Appropriateness for Cystitis in Older Nursing Home Residents: A Quality Improvement Study With Randomized Assignment

Abstract

ObjectiveTo determine the impact of an educational quality improvement initiative on the appropriateness of antibiotic prescribing restricted to uncomplicated cystitis in older noncatheterized nursing home residents. DesignQuality improvement study with randomized assignment. Settings and ParticipantsTwenty-five nursing homes in United States were randomized to the intervention or usual care group by strata that included state, urban/rural status, bed size, and geographic separation. MethodsA 12-month trial of a low-intensity multifaceted antimicrobial stewardship intervention focused on uncomplicated cystitis in nursing home residents vs usual care. The outcome was the modified Medication Appropriateness Index as assessed by a blinded geriatric clinical pharmacist and consisted of an assessment of antibiotic effectiveness, dosage, drug-drug interactions, and duration. ResultsThere were 75 cases (0.15/1000 resident days) in intervention and 92 (0.22/1000 resident days) in control groups with a probable cystitis per consensus guidelines. Compared with controls, there was a statistically nonsignificant 21% reduction in the risk of inappropriate antibiotic prescribing (nonzero Medication Appropriateness Index score rate 0.13 vs 0.21/1000 person days; adjusted incident rate ratio 0.79; 95% confidence interval 0.45‒1.38). There was a favorable comparison in inappropriateness of duration (77% vs 89% for intervention vs control groups, respectively; P = .0394). However, the intervention group had more problems with drug-drug interactions than the control group (8% vs 1%, respectively; P = .0463). Similarly, the intervention group had a nonsignificant trend toward more problems with dosage (primarily because of the lack of adjustment for decreased renal function) than the control group (32% vs 25%, respectively; P = .3170). Both groups had similar rates of problems with choice/effectiveness (44% vs 45%; P = .9417). The most common class of antibiotics prescribed inappropriately was quinolones (25% vs 23% for intervention versus control groups, respectively; P = .7057). Conclusions and ImplicationsA low-intensity intervention showed a trend toward improved appropriate antibiotic prescribing in nursing home residents with likely uncomplicated cystitis. Efforts to improve antibiotic prescribing in addition to the low-intensity intervention might include a consultant pharmacist in a nursing home to identify inappropriate prescribing practices.