Minimally invasive surgical therapies (MIST) for benign prostatic hyperplasia (BPH) are expected to reduce lower urinary tract symptoms (LUTS) and medication burden. However, the extent to which storage symptoms, particularly overactive bladder (OAB), improve remains unclear.
We aimed to evaluate temporal changes in LUTS-related medication use and to identify predictors of postoperative OAB medication requirement following MIST.

This multicenter retrospective study included patients undergoing Water Vapor Thermal Therapy (WVTT) or Prostatic Urethral Lift (PUL). Changes in BPH medications, OAB medications, and anticholinergic use were assessed at baseline and at 1, 3, and 6 months postoperatively.
Multivariable logistic regression was used to identify predictors of postoperative OAB medication use. Sensitivity analysis for de novo OAB and inverse probability of treatment weighting (IPTW) were performed to confirm robustness.

A total of 164 patients (WVTT n=107; PUL n=57) were analyzed.
BPH medication use significantly decreased in both groups (median 2→0, p<0.001), indicating a substantial reduction in pharmacological burden.
In contrast, OAB medication use did not significantly change over time. Anticholinergic use decreased in the WVTT group (p<0.05), although the proportion of patients requiring OAB medication remained largely unchanged.
Multivariable analysis identified baseline OAB medication use as a strong independent predictor of postoperative OAB medication requirement (OR 7.37, 95% CI 2.32–23.40, p<0.001). No significant associations were observed for age, prostate volume, intravesical prostatic protrusion, or surgical modality.
Sensitivity analyses, including de novo OAB and IPTW adjustment, confirmed the robustness of these findings and demonstrated no significant differences between WVTT and PUL.

While MIST effectively alleviates obstruction and reduces voiding-related medication burden, storage symptoms appear to follow a distinct clinical trajectory. The persistence of OAB medication use, together with the strong predictive value of baseline OAB status, suggests that storage dysfunction is largely independent of bladder outlet obstruction and only partially reversible.
These findings provide real-world evidence of a pathophysiological dissociation between voiding and storage symptoms, indicating that postoperative OAB reflects underlying bladder dysfunction rather than residual obstruction.
Clinically, this highlights the need for a paradigm shift in perioperative management: patients with pre-existing OAB should be recognized as a distinct phenotype requiring tailored strategies, including continued or adjunctive pharmacotherapy beyond surgical intervention.

MIST reduces obstruction-related symptoms but does not fully resolve storage dysfunction. Baseline OAB status defines a distinct clinical phenotype and should guide individualized postoperative management strategies.