Therapeutic outcomes and predictive factors of intradetrusor onabotulinumtoxinA for neurogenic detrusor overactivity (NDO) associated with spinal cord lesion.

[PURPOSE] Intradetrusor onabotulinumtoxinA (Botox) is an established treatment for neurogenic detrusor overactivity (NDO), although predictors of success remain unclear. This study evaluated the therapeutic efficacy of Botox and identified predictors of response in patients with spinal cord lesion (SCL)-related NDO.

[METHODS] We retrospectively reviewed 167 patients with SCL-related NDO who received intradetrusor 200 U Botox at a single center between January 1, 2002, and December 31, 2024. Treatment response was classified using the Global Response Assessment (GRA) as excellent (GRA = 3), moderately improved (GRA = 2), mildly improved (GRA = 1), or no change (GRA = 0). Success was defined as GRA = 3 or 2. Baseline demographics, neurological level, and videourodynamic (VUDS) parameters, including detrusor pressure at maximum flow (Pdet), maximum flow rate, voided volume, post-void residual, voiding efficiency (VE), bladder outlet obstruction index (BOOI), and bladder contractility index (BCI), were analyzed as predictors.

[RESULTS] VUDS confirmed detrusor overactivity in 92.8%. Overall, 51.5% (86/167) achieved an excellent response, 43.1% (72/167) improved, and 5.4% (9/167) showed no change. Outcomes did not differ by neurological level (P = 0.665). Patients with successful outcomes had higher baseline P (41.9 ± 20.3 vs 22.9 ± 13.4 cmH₂O, P < 0.001), BOOI (33.2 ± 21.9 vs 12.7 ± 15.2, P < 0.001), and BCI (63.6 ± 33.0 vs 48.4 ± 27.9, P = 0.010), but lower VE (0.28 ± 0.31 vs 0.40 ± 0.35, P = 0.045). Logistic regression analysis showed that higher Pdet, BOOI, and BCI predicted treatment success, while higher VE predicted nonresponse. Sex distribution differed across GRA groups (P = 0.004), with more men in the failure group. Acute adverse events were similar among groups.

[CONCLUSIONS] Intradetrusor Botox produced good efficacy in SCL-related NDO. Higher baseline detrusor pressure, bladder contractility, and bladder outlet resistance predicted better outcomes, whereas greater VE was associated with nonresponse. Neurological level did not influence treatment success.