Bladder training for treating overactive bladder in adults

Overactive bladder (OAB) is a common chronic and bothersome condition. Bladder training is widely prescribed as a first-line treatment for OAB, but the efficacy has been systematically evaluated for urinary incontinence rather than OAB alone.To evaluate the benefits and harms of bladder training for treating adults with OAB compared to no treatment, anticholinergics, β3-adrenoceptor agonists, or pelvic floor muscle training (PFMT) alone or in combination.We used standard, extensive Cochrane search methods. The latest search date was 6 November 2022.We included randomized controlled trials involving adults aged 18 years or older with non-neurogenic OAB. We excluded studies of participants whose symptoms were caused by factors outside the urinary tract (e.g. neurologic disorders, cognitive impairment, gynecologic diseases).We used standard Cochrane methods. Our primary outcomes were 1. participant-reported cure or improvement, 2. symptom- and condition-related quality of life (QoL), and 3.Secondary outcomes included 4. participant-reported satisfaction, 5. number of incontinence episodes, 6. number of urgency episodes, and 7. number of micturition episodes. For the purpose of this review, we considered two time points: immediately after the treatment (early phase) and at least two months after the treatment (late phase). We used GRADE to assess certainty of evidence for each outcome.We included 15 trials with 2007 participants; participants in these trials were predominantly women (89.3%). We assessed the risk of bias of results for primary and secondary outcomes, which across all studies was similar and predominantly of high risk of bias, and none were at low risk of bias. The certainty of evidence was low to very low, with some moderate, across measured outcomes. Bladder training versus no treatment: three studies involving 92 participants compared bladder training to no treatment. The evidence is very uncertain about the effects of bladder training on cure or improvement at the early phase (risk ratio (RR) 17.00, 95% confidence interval (CI) 1.13 to 256.56; 1 study, 18 participants; very low-certainty evidence). Bladder training may reduce the number of incontinence episodes (mean difference (MD) -1.86, 95% CI -3.47 to -0.25; 1 study, 14 participants; low-certainty evidence). No studies measured symptom- and condition-related QoL, number of adverse events, participant-reported satisfaction, number of urgency episodes, or number of micturition episodes in the early phase. Bladder training versus anticholinergics: seven studies (602 participants) investigated the effects of bladder training versus anticholinergic therapy. Bladder training may be more effective than anticholinergics on cure or improvement at the early phase (RR 1.37, 95% CI 1.10 to 1.70; 4 studies, 258 participants; low-certainty evidence). The evidence is very uncertain about the effects of bladder training on symptom- and condition-related QoL (standardized mean difference (SMD) -0.06, 95% CI -0.89 to 0.77; 2 studies, 117 participants; very low-certainty evidence). Although the evidence is very uncertain, there were fewer adverse events in the bladder training group than in the anticholinergics group (RR 0.03, 95% CI 0.01 to 0.17; 3 studies, 187 participants; very low-certainty evidence). The evidence is very uncertain about the effects of the number of incontinence episodes per 24 hours (MD 0.36, 95% CI -0.27 to 1.00; 2 studies, 117 participants; very low-certainty evidence), the number of urgency episodes per 24 hours (MD 0.70, 95% CI -0.62 to 2.02; 2 studies, 92 participants; very low-certainty evidence), and the number of micturition episodes per 24 hours (MD -0.35, 95% CI -1.90 to 1.20; 3 studies, 175 participants; very low-certainty evidence). No studies measured participant-reported satisfaction in the early phase. Bladder training versus PFMT: three studies involving 203 participants compared bladder training to PFMT. The evidence is very uncertain about the different effects between bladder training and PFMT on symptom- and condition-related QoL at the early phase (SMD 0.10, 95% CI -0.19 to 0.40; 2 studies, 178 participants; very low-certainty evidence). There were no adverse events in either group at the early phase (1 study, 97 participants; moderate-certainty evidence). The evidence is uncertain about the effects of the number of incontinence episodes per 24 hours (MD 0.02, 95% CI -0.35 to 0.39, 1 study, 81 participants; low-certainty evidence) and very uncertain about the number of micturition episodes per 24 hours (MD 0.10, 95% CI -1.44 to 1.64; 1 study, 81 participants; very low-certainty evidence). No studies measured cure or improvement, participant-reported satisfaction, or number of urgency episodes in the early phase. Although we were interested in studies examining bladder training versus β3-adrenoceptor agonists, in combination with β3-adrenoceptor agonists versus β3-adrenoceptor agonists alone, and in combination with PFMT versus PFMT alone, we did not identify any eligible studies for these comparisons.This review focused on the effect of bladder training to treat OAB. However, most of the evidence was low or very-low certainty. Based on the low- or very low-certainty evidence, bladder training may cure or improve OAB compared to no treatment. Bladder training may be more effective to cure or improve OAB than anticholinergics, and there may be fewer adverse events. There may be no difference in efficacy or safety between bladder training and PFMT. More well-designed trials are needed to reach a firm conclusion.