**Chung-Cheng Wang 1,2, Yung-Hong Jiang <sup>3</sup> and Hann-Chorng Kuo 3,\***


Received: 1 March 2020; Accepted: 15 March 2020; Published: 16 March 2020

**Abstract:** Diabetes mellitus (DM) is an independent risk factor for overactive bladder (OAB). The pathophysiology of DM-associated OAB is multifactorial and time-dependent. Diabetic bladder dysfunction is highly associated with diabetic complications, mainly including diabetic neuropathy and atherosclerosis. Chronic systemic inflammation and bladder urothelial inflammation may contribute to the onset of OAB. Intravesical botulinum toxin A (BoNT-A) injection has proved to be a successful treatment for idiopathic and neurogenic OAB. BoNT-A can inhibit the efferent pathways of the bladder as well as the chronic inflammation and hypersensitivity via the afferent pathways. We conducted a review of the published literature in Pubmed using a combination of two keywords, namely "botulinum toxin A" (BoNT-A) and "overactive bladder", with or without the additional keywords "detrusor overactivity", "diabetes mellitus", "inflammation", and "urodynamic study". We also reviewed the experience of our research teams, who have published several studies of the association between DM and OAB. Since limited data support the effectiveness and safety of BoNT-A for treating patients with DM-associated OAB, a comprehensive evaluation of diabetic complications and urodynamic study is needed before treatment. In the future, it is imperative to explore the clinical characteristics and inflammatory biomarkers of diabetes as determining predictors of the treatment efficacy.

**Keywords:** diabetes mellitus; overactive bladder; inflammation; botulinum toxin

**Key Contribution:** Through inhibiting chronic inflammation and hypersensitivity of urinary bladder, intravesical BoNT-A injection appears to be effective and safe in patients with DM-associated OAB. A comprehensive evaluation of DM complications and urodynamic studies is needed before treatment.
