Moriarty, F.; Razzaque, S.; McDowell, R.; Fahey, T. Prescribing Variation in General Practices in England Following a Direct Healthcare Professional Communication on Mirabegron. J. Clin. Med.2018, 7, 320.
Moriarty, F.; Razzaque, S.; McDowell, R.; Fahey, T. Prescribing Variation in General Practices in England Following a Direct Healthcare Professional Communication on Mirabegron. J. Clin. Med. 2018, 7, 320.
Moriarty, F.; Razzaque, S.; McDowell, R.; Fahey, T. Prescribing Variation in General Practices in England Following a Direct Healthcare Professional Communication on Mirabegron. J. Clin. Med.2018, 7, 320.
Moriarty, F.; Razzaque, S.; McDowell, R.; Fahey, T. Prescribing Variation in General Practices in England Following a Direct Healthcare Professional Communication on Mirabegron. J. Clin. Med. 2018, 7, 320.
Abstract
Introduction Pharmacovigilance may detect safety issues after marketing of medications, and this can result in regulatory action such as direct healthcare professional communications (DHPC). DHPC can be effective in changing prescribing behaviour, however the extent to which prescribers vary in their response to DHPC is unknown. This study aims to explore changes in prescribing and prescribing variation among GP practices following a DHPC on the safety of mirabegron, a medication to treat overactive bladder (OAB). Methods This is an interrupted time series study of English GP practices from 2014-2017. NHS Digital provided monthly statistics on aggregate practice-level prescribing and practice characteristics (practice staff and registered patient profiles, Quality & Outcomes Framework indicators, and deprivation of the practice area). The primary outcome was monthly mirabegron items as a percentage of all OAB drug items. The exposure was a DHPC issued by the European Medicines Agency in September 2015. Variation between practices in mirabegron prescribing before and after the DHPC was assessed using the systematic component of variation (SCV). Multilevel segmented regression with random effects quantified the change in level and trend of prescribing after the DHPC. Practice characteristics were assessed for their association with a reduction in prescribing following the DHPC. Results This study included 7,408 practices. During September 2015, 88.9% of practices prescribed mirabegron and mirabegron composed a mean of 8.2% (SD 6.8) of OAB items. Variation between practices was classified as very high and the median SCV did not change significantly (p=0.11) in the 6 months after the September 2015 DHPC (12.4) compared to before (11.6). Before the DHPC, there was a monthly trend of 0.294 (95%CI, 0.287, 0.301) percentage points increase in mirabegron percentage. There was no significant change in the month immediately after the DHPC (-0.023, 95% CI -0.105 to 0.058) however there was a significant reduction in trend (-0.036, 95% CI -0.049 to -0.023). Higher numbers of registered patients and patients aged ≥65 years, and practice area deprivation were associated with having a significant decrease in level and slope of mirabegron prescribing post-DHPC. Conclusion Variation in mirabegron prescribing was high over the study period and did not change substantively following the DHPC. There was no immediate prescribing change post-DHPC, although the monthly growth did slow. Knowledge of the degree of variation in and determinants of response to safety communications may allow those that do not change prescribing to be provided with additional supports.
Keywords
pharmacovigilance; drug safety; segmented regression; interrupted time series; variation
Subject
Medicine and Pharmacology, Pharmacology and Toxicology
Copyright:
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