Despite increasing adoption of neuromodulation to treat overactive bladder (OAB), percutaneous tibial nerve stimulation (PTNS) dropout rates appear high.
In a real-world study of 163 patients from a urology clinic in Stony Brook, New York, only 104 completed the initial 12 weeks of PTNS and just 81 proceeded with maintenance therapy administered every 1 to 6 weeks. Dropout rates increased over 1 year. At 3, 6, 9, and 12 months, only 77.8%, 58.0%, 45.6%, and 39.5% of patients, respectively, were still compliant with PTNS, Chris Du, MD, of Stony Brook Medicine, and colleagues reported in Urology.
The top reasons for dropout were worsening of urinary symptoms/lack of efficacy reported by 21 patients, burdensome time commitment reported by 9, loss of insurance reported by 5, medical comorbidities such as a cancer diagnosis reported by 4, request for alternative OAB treatment mentioned by 2, and unknown reasons ascribed to 8.
On univariate analysis only, significantly more patients who completed 12 months of maintenance than who dropped out reported continued symptom improvement of more than 50%: 97% vs 59%, respectively. Notably, significantly more patients with multiple sclerosis (44% vs 18%) and any neurologic history (56% vs 29%) continued the third-line treatment for 12 months. Gender, race, Medicare, employment, distance to clinic, disability, pre-PTNS urinary symptoms, and smoking status did not predict continuation.
“These dropout rates are comparable to compliance rates at one year (22-33%) with medical OAB therapy,” Dr Du’s team wrote. For patients with multiple sclerosis or neurological history, “[i]t is likely that the increased urologic risk of neurogenic bladder in these patients leads to higher rates of compliance,” the investigators suggested.
According to the study authors, future studies are needed to better understand the high PTNS dropout rates and whether innovations such as the implantable tibial nerve-stimulating device improves these rates.
Du C, Berg W, Siegal AR, et al. Real-world compliance with percutaneous tibial nerve stimulation maintenance therapy in an American Population. Published online February 10, 2021. Urology. doi:10.1016/j.urology.2021.02.005