Effect of a multifaceted antibiotic stewardship intervention to improve antibiotic prescribing for suspected urinary tract infections in frail older adults (ImpresU): pragmatic cluster randomised controlled trial in four European countries.

Objective: To evaluate whether antibiotic prescribing for suspected urinary tract infections in frail older adults can be reduced through a multifaceted antibiotic stewardship intervention.

Design: Pragmatic, parallel, cluster randomised controlled trial, with a five month baseline period and a seven month follow-up period.

Setting: 38 clusters consisting of one or more general practices (n=43) and older adult care organisations (n=43) in Poland, the Netherlands, Norway, and Sweden, from September 2019 to June 2021.

Participants: 1041 frail older adults aged 70 or older (Poland 325, the Netherlands 233, Norway 276, Sweden 207), contributing 411 person years to the follow-up period.

Intervention: Healthcare professionals received a multifaceted antibiotic stewardship intervention consisting of a decision tool for appropriate antibiotic use, supported by a toolbox with educational materials. A participatory-action-research approach was used for implementation, with sessions for education, evaluation, and local tailoring of the intervention. The control group provided care as usual.

Main Outcome Measures: The primary outcome was the number of antibiotic prescriptions for suspected urinary tract infections per person year. Secondary outcomes included the incidence of complications, all cause hospital referrals, all cause hospital admissions, all cause mortality within 21 days after suspected urinary tract infections, and all cause mortality.

Results: The numbers of antibiotic prescriptions for suspected urinary tract infections in the follow-up period were 54 prescriptions in 202 person years (0.27 per person year) in the intervention group and 121 prescriptions in 209 person years (0.58 per person year) in the usual care group. Participants in the intervention group had a lower rate of receiving an antibiotic prescription for a suspected urinary tract infection compared with participants in the usual care group, with a rate ratio of 0.42 (95% confidence interval 0.26 to 0.68). No differences between intervention and control group were observed in the incidence of complications (<0.01 0.05 per person year), hospital referrals (<0.01 0.05), admissions to hospital (0.01 0.05), and mortality (0 0.01) within 21 days after suspected urinary tract infections, nor in all cause mortality (0.26 0.26).

Conclusions: Implementation of a multifaceted antibiotic stewardship intervention safely reduced antibiotic prescribing for suspected urinary tract infections in frail older adults.

Trial Registration: ClinicalTrials.gov NCT03970356.