Polypharmacy reviews in prison healthcare: a pilot service evaluation

Abstract Introduction The prison population experiences disproportionately high healthcare complexity, with medication burden rates significantly higher than the general population.[1] Despite the increased polypharmacy risk and significant anticholinergic burden (ACB), the nursing service-led prison healthcare system in HMP Edinburgh (HMPE), a male residential prison, lacked integrated clinical pharmacy input. In response to this service gap and evidence of medication-related harm, the first onsite lead pharmacist and trainee pharmacist initiated a pilot polypharmacy service. An evaluation of this pilot service is essential to understand resource requirements for equitable care in prisons. Aim To evaluate the implementation of a polypharmacy review pilot service delivered by a lead pharmacist and a trainee pharmacist within HMPE. Methods Based on size and ageing population demographics, one residential hall was selected from HMPE with resident capacity of 872. Patients in this hall with more than eight long-term medications participated in polypharmacy reviews between April–July 2025. Patients were identified through manual review of paper prescribing records. Selection criteria and reviews were structured on Scottish government polypharmacy guidance protocols. Clinical review process used ACB Calculator, formulary guidelines, and renal function assessments. Face-to-face reviews were supported with national patient reported outcome measure (PROM) questionnaires, completed a week before and a week after appointment. Polypharmacy reviews focused on Realistic Medicine principles, safe evidence-based prescribing, and involved local multidisciplinary team. Outcomes assessed were clinical interventions per patient, ACB scores, time taken for case review pre-appointment, and PROMs. Results Of the hall’s 100 residents, 21 met the inclusion criteria. Sixteen comprehensive reviews were completed within the trainee pharmacist placement time constraints. Median number of medications was 10 (IQR 9–13), with lengthy review duration of 90 minutes (IQR 75–120) due to paper-based systems and fragmented clinical data. Five reviews (31%) required ≥120 minutes. Median baseline ACB scores were 5 (IQR 2.5–6), with 9/16 patients (60%) having scores ≥5, significantly exceeding the clinical threshold of 3 associated with increased risks of cognitive impairment and adverse outcomes.[2] Median interventions per patient were 2 (IQR 2–4). Interventions aligned with national polypharmacy indicators included missed folic acid supplementation with high-dose methotrexate (30 mg), delayed diabetes medication initiation, and inappropriate inhaler therapy. Clinical interventions reduced ACB scores, including one significant score reduction from 7 to 2. PROM data indicated improved patient understanding of medications, with qualitative feedback: ‘You explained the medication changes to me and nobody does that here.’ Conclusion This pilot service evaluation provides preliminary evidence supporting the need for polypharmacy services in custody settings. Key strengths include successfully implementing evidence-based polypharmacy interventions in an understudied, vulnerable population. Small sample size and lack of follow-up data limit applicability to wider populations. Community patients receive annual polypharmacy reviews; HMPE patients previously had none. This pilot reduces access disparity for a high-risk population. Future work should focus on scaling up with dedicated pharmacy technician support to reduce pharmacist review time and include evaluation with sustained follow-up on patient outcomes. The interventions and outcomes support clear rationale for enhanced clinical pharmacy resources to address healthcare inequities in custody settings.