Association analysis of ADRB3:rs4994 with urodynamic outcome, six months after a single intra-detrusor injection of botulinum toxin, in women with overactive bladder

Intra-detrusor injection of botulinum neurotoxin type A (BoNT/A) is recommended as a possible treatment for patients with overactive bladder (OAB) in whom first-line therapies have failed. The c.190T > C (rs4994) polymorphism in the gene encoding the beta-3 adrenergic receptor (ADRB3) has been suggested to be associated with predisposition to OAB or with response to OAB treatment via a cholinergic muscarinic receptor antagonist. This prospective study aimed to use a urodynamic parameter-based assessment of response, six months after a single intra-detrusor injection of BoNT/A in female OAB patients, to elucidate possible association with the ADRB3 polymorphism.

The study group consisted of 138 consecutive, Polish, adult, female OAB patients. Urodynamic parameters were recorded before injection of BoNT/A and at six months after administration. ADRB3:rs4994 variants were identified by the sequencing of genomic DNA extracted from buccal swabs.

Apart from baseline, and relative, increase in Maximum Cystometric Capacity (MCC) six months after BoNT/A injection, no significant differences were found in urodynamic parameters between reference TT homozygotes and women with at least one C allele.

Our results do not exclude that ADRB3:rs4994 variants are associated with a positive urodynamic test-based response to intra-detrusor injection of BoNT/A in females with OAB.