In how many patients urodynamics should be omitted? Data from a single-centre database on the basis of the upstream trial

The role of invasive urodynamics (iUDS) before surgery for benign prostatic obstruction (BPO) is debated. The UPSTREAM trial showed that adding iUDS to routine care does not decrease the number of patients who will undergo surgery nor ensure better outcomes after surgery. Ito and coworkers showed that patients could be divided into two categories according to certain parameters. The primary aim of this study was to determine the proportion of patients with BPO undergoing iUDS who exhibit characteristics predictive of good surgical outcome. This retrospective study included consecutive male patients with BPO and lower urinary tract symptoms (LUTS) who underwent iUDS at our centre between January 2013 and March 2024. Patients were categorized based on UPSTREAM trial criteria for good surgical outcomes (IPSS > 16, IPSS QoL > 4, Q max < 9.8 mL/s, age ≤ 74 years). Further analysis examined bladder outlet obstruction index (BOOI ≥ 48) and bladder contractility index (BCI ≥ 123). Among 212 patients analysed, 38.2% met all criteria for good surgical outcomes, while 61.8% exhibited at least one unfavourable criterion. In particular, 90/131 patients had one unfavourable criterion, 32/131 had two, and 9/131 had three. Among these patients, concerning BOOI and BCI analysis, 74% had a BCI < 123, 48.1% had a BOOI < 48, and 45% had both a BCI < 123 and BOOI < 48. Our findings suggest that fewer than 40% of patients undergoing iUDS before potential BPO surgery have a good prognosis based on clinical characteristics. Among those with ‘unfavourable criteria’, given the high prevalence of detrusor underactivity (DU) and non-obstructive profiles, urodynamics may refine and optimize surgical selection.