A possible association between pharmacological treatment of overactive bladder (OAB) and cognitive decline has been described. This is the first prospective study assessing the effect of pharmacological treatment with antimuscarinics and/or beta-3 agonists on cognitive function in patients with OAB syndrome with a 6-month follow-up.

A non-experimental before-and-after study was conducted in patients with OAB, with an indication to start pharmacological treatment with antimuscarinics and/or beta-3 agonists. The Mini-Mental State Examination (MMSE) test was administered before treatment, at 3 and 6 months of follow-up.  To evaluate the relationship between the primary outcome (changes in cognitive function), the delta of the MMSE was calculated, comparing the initial score with the scores three and six months after treatment initiation. The relationship between changes in MMSE scores and exposure factors was analyzed, along with a descriptive analysis based on the variable type. The calculated sample size was 74 patients (power = 0,8; alfa error = 0,05 ).

A total of 116 patients with OAB were included. 72% of patients completed three and six months of follow-up, while the remaining 28% completed only three months. 74% of patients were treated with beta-3 agonists, 24% with antimuscarinics, and 0,8% received combined therapy. The pre-treatment prevalence of mild cognitive impairment was 20,6%, and the cumulative overall incidence was 15% at six months. When evaluating the effect of treatment, it was observed that 21,9% of patients had a statistically significant decrease of two or more units in the MMSE score at 3 months and 7,6% at six months (p = 0,0278). The MMSE domains were evaluated independently, finding that at three months, time orientation, place orientation, attention, and language showed a significant change in the mean scores, while at six months, all domains presented a substantial decrease. No significant differences were found between the treatment groups when comparing the delta in MMSE scores between beta-3 agonists and antimuscarinics.

These results suggest that pharmacological treatment for OAB syndrome does show a negative effect on cognitive function for both antimuscarinics and beta-3 agonists after three and six months of treatment. A significant decline is observed in all evaluated domains of the MMSE after six months. Our results differed with previous studies that showed no significant differences between treatment with beta-3 agonists and placebo in cognitive function and studies that showed a higher risk with antimuscarinics than with beta-3 agonists, which wasn’t observed in this cohort.

The treatment of OAB syndrome with anticholinergics and/or beta-3 agonists is associated with a negative impact on cognitive function after three and six months of follow-up. Given the population’s aging and the risk of cognitive decline, physicians must consider the use of screening tools such as the MMSE. Overall, the findings reinforce the need for careful monitoring of the cognitive effects of overactive bladder treatment.

Wagg A, Staskin D, et al. Eur Urol . 2020 Feb;77(2):211-220
Dmochowski RR, Thai S, etl al. Neurourol Urodyn. 2021;40(1):28–37