Impact of anticholinergic load on bladder function.

INTRODUCTION AND HYPOTHESIS

Our aim was to evaluate the impact of anticholinergic load on urinary retention based on postvoid residual (PVR) on micturition study. Secondary objectives were to assess the effect of anticholinergic load on other urodynamic parameters.

METHODS

This was a retrospective cohort study of women who underwent urodynamics (UDS) at one academic institution. All medications being taken by the women at the time of UDS were scored using the anticholinergic risk scale (ARS). This validated scale assigns rank scores to each medication based on its anticholinergic potential. Women were dichotomized into two anticholinergic cohorts: low (0-1) or high (≥2) ARS scores.

RESULTS

During the study period, 599 women underwent UDS. ARS scores ranged from 0 to 8, with 440 (73.5 %) having low (≤1) and 159 (26.5 %) having high (≥2) scores. For our primary outcome of micturition PVR, there was no difference between low and high ARS groups (66.8 ± 108.6 ml vs. 78.6 ± 121.0 ml, p = 0.25). There was also no difference between ARS groups in other voiding function parameters. Sensitivity analyses did demonstrate a difference in micturition PVR, with ARS 0-4 (n = 583) vs. ARS ≥ 5 (n = 16): 68.3 ± 109.1 ml vs. 127.5 ± 185.7 (p < 0.01) ,as well as maximum cystometric capacity (MCC): 420.8 ± 181.3 ml vs. 526.1 ± 252.4 ml (p = 0.02).

CONCLUSIONS

Despite the prevalence and risks associated with the use of medications with anticholinergic properties, a cumulative effect on bladder function was only demonstrated with very high anticholinergic risk scores of ≥5.