From Missed to Flagged: NWL’s 5‑ARI PSA Safety Prompts

Hammersmith & Fulham Partnership

Project summary

Patients on 5‑alpha‑reductase inhibitors (5‑ARIs) have PSA levels reduced by about half. If this isn’t recognised, cancer risk can be underestimated and two‑week‑wait (2WW) referrals delayed. In January 2024, I set out to create a reliable, system‑level fix across our Hammersmith & Fulham PCN (~70–80k population), moving beyond ad‑hoc education.

I began with an audit at my practice. In January 2025, a search found 58 patients on 5‑ARIs; several needed urology input to ensure PSA interpretation was adjusted. We added script notes and a prominent home‑page reminder on each record to “double PSA if on 5‑ARI.” In August 2025, a re‑audit still found 31 patients and three needing 2WW consideration.

Meanwhile another PCN practice had a late prostate cancer diagnosis where a PSA result was not adjusted for a 5‑ARI. Their search found 30 patients; they adopted the same notes and reminders. A third practice found 25 patients (one 2WW, two urology referrals). A fourth found 39 (two 2WW, one repeat PSA). A fifth had 25 patients (2WW data unavailable). These results showed education and local reminders helped but did not make safety consistent.

To make safety reliable at scale, in August 2025 I proposed a system change to NWL pathology/radiology: add a simple 5‑ARI checkbox with brief guidance to the PSA request form, and include an automatic interpretive comment on PSA results reminding clinicians to adjust values (double the PSA) when a patient is on a 5‑ARI, with a nudge to consider 2WW if thresholds are met. NWL agreed, creating two decision‑support prompts at ordering and at result review.

Early outcomes across the PCN indicate better case‑finding and timelier escalation. Post‑implementation, practices reported clearer documentation that PSA was adjusted for 5‑ARI use and additional patients identified for urgent assessment, consistent with the cases above. Patients benefited from clearer explanations, fewer unnecessary repeat tests, and faster movement onto the right pathway.

This approach aligns with medicines optimisation principles: it improves patient safety, embeds evidence into routine practice, and supports multidisciplinary working between primary care, pathology/radiology IT, and urology. It is low‑cost and highly replicable: one request‑form checkbox and a standardised result comment that work across systems. While formal ROI data are not yet captured, the change saves clinical time otherwise spent re‑auditing and re‑reviewing borderline results and is expected to reduce avoidable repeats and delays—delivering value for patients and the NHS at scale.