Abstract / Summary
Aim To quantify between‐practice variation in potentially inappropriate prescribing (PIP) among middle‐aged adults (45–64 years) in UK general practice, and to identify patient‐ and practice‐level characteristics associated with PIP. Methods Repeated cross‐sectional study using linked data from the Lambeth DataNet and Quality Outcomes Framework across 41 GP practices in South London (2014–2019). The study included patients aged 45–64 years prescribed ≥1 medicines in each year from 2014 to 2019 ( n = 46 633–52 582). PIP was identified using the 22 PROMPT (PRescribing Optimally in Middle‐aged People's Treatments) criteria. Multilevel negative binomial regression estimated associations with patient‐ and practice‐level characteristics, expressed as rate ratios (RR) with 95% confidence intervals. Results PIP prevalence was 18%–20%, stable across the study period. Practice‐level prevalence ranged from 14% to 24%. The SCV was 1.72 (low) and the ICC was 0.08, with approximately 8% of variance attributable to practice‐level differences. Polypharmacy was the strongest predictor (adjusted RR 4.04, 95% CI 3.96–4.11), followed by multimorbidity (RR 2.44, 95% CI 2.40–2.50). Black/African/Caribbean/Black British ethnicity was associated with lower PIP (RR 0.77, 95% CI 0.75–0.78). Practice‐based pharmacist presence and teaching practice status were associated with modestly lower PIP, while APMS contract type was associated with higher PIP (RR 1.20, 95% CI 1.10–1.32). Conclusion Most variation occurred at the patient level, but practice organizational characteristics were also associated with PIP and warrant further investigation in an age group for which direct medicines‐optimization evidence remains limited.