Urinary Cytokines in Predicting Intradetrusor Onabotulinumtoxin-A Response

The impact of asymptomatic bacteriuria and inflammation on response to Onabotulinumtoxin-A for overactive bladder is poorly understood. This work compares baseline differences in asymptomatic bacteriuria status and urinary inflammatory markers between women who respond to Onabotulinumtoxin-A and those who do not.

Women undergoing intradetrusor Onabotulinumtoxin-A injection for refractory overactive bladder submitted a catheterized urine sample to assess for asymptomatic bacteriuria and quantification of 12 urinary cytokines and chemokines at the time of injection. Clinical responders were defined as meeting a minimal clinical difference of > 11 on the Urinary Distress Inventory Short Form after treatment. The proportion of asymptomatic bacteriuria and concentration of urinary biomarkers in Onabotulinumtoxin-A responders compared to non-responders were analyzed.

Of the 75 participants, 45 (60%) were Onabotulinumtoxin-A responders. Responders did not differ in baseline characteristics apart from age (66.0 ± 14.2 [responders] vs. 74.3 ± 7.8 years [non-responders], p < 0.01). There was no difference in asymptomatic bacteriuria rates in responders (37.8%) versus non-responders (40.7%, p = 0.09). No single inflammatory marker was predictive of treatment response when controlling for age. Decision tree analysis allowed for 80% classification accuracy of responders. MCP1 and IP10 were major features in the decision tree analysis, but their impact varied by age. Adding asymptomatic bacteriuria to the decision tree analysis did not improve classification nor function as an important predictive feature.

Asymptomatic bacteriuria does not affect Onabotulinumtoxin-A response. Older women were less likely to respond to Onabotulinumtoxin-A treatment and experienced a differential impact of inflammatory cytokines.