Effectiveness of an intervention to optimise the use of mirabegron for overactive bladder: a quasi-experimental study in primary care

Abstract

Background: Overactive bladder is a composite of lower urinary tract storage symptoms. Pharmacological treatment is widely employed despite markedly modest efficacy data, adverse effects, and costs for the health system.

Aim: To determine the 12-month efficacy of an intervention delivered by GPs on mirabegron revision and, if appropriate, discontinuation of treatment.

Design and setting: Multicentre, quasi-experimental study in Barcelona (Catalonia), Spain.

Method: Two groups composed of 17 intervention and 34 control practices were formed. The follow-up period was 12 months, from 1 January to 31 December 2017. A structured intervention was designed consisting of initiatives with GPs and urology/gynaecology specialists. The primary outcome was mirabegron use at 12 months.

Results: Of the 1932 patients, a significant discontinuation in treatment was observed at 12 months' follow-up in the intervention group (IG) (n = 433 out of 762, 56.8%), in contrast with the control one (CG) (n = 484 out of 1170, 41.4%) (P<0.001). There was also a reduced incorporation of new treatments in the IG (n = 214 out of 762, 28.1%) compared with the CG (n = 595 out of 1170, 50.9%) (P<0.001). In relation to patients with treatment at the beginning and end of the period, there was a decrease of 219 (28.7%) patients in the IG and an increase of 111 (9.5%) in the CG (P<0.001).

Conclusion: The structured intervention showed optimisation in the use of mirabegron. When considering discontinuation it is necessary to provide clear data on the benefits and/or risks for patients and their caregivers, as such information is a precondition for shared decision making.

Keywords: costs; deprescribing; mirabegron; overactive bladder; patient-centred care; persistence (time to discontinuation).

Figure 1.

Flow of patients treated with mirabegron and intervention performed. PHCS = primary healthcare service.

Figure 2.

Follow-up of patients under treatment with mirabegron from January to December 2017, by control and intervention groups. New treatments are also included.

Figure 3.

Change over the baseline period (December versus January 2017) of the number of patients treated with mirabegron, by the primary care service, control group, and intervention group. Patients without discontinuation of treatment and new patients are included. CG = control group. IG = intervention group. PHCS = primary healthcare service. ^aDifferences between CG and IG (P<0.001).

Figure 4.

Change in the baseline of patients treated with mirabegron adjusted by the population served, by intervention and control groups. CG = control group. IG = intervention group. PHCS = primary health are service. ^aDifferences between the intervention and control groups (P<0.001).