INTRODUCTION AND OBJECTIVES: The Sustained Therapeutic Effects of Percutaneous Tibial Nerve Stimulation (STEP) Study evaluated long term therapy effectiveness with percutaneous tibial nerve stimulation (PTNS) for overactive bladder symptoms (OAB). The objective of this review is to evaluate the treatment interval frequency though 12 months of sustained therapy.
METHODS: Subjects participating in STEP who met the primary endpoint of success after 12 weekly PTNS treatments were invited to participate in the long term study. Subjects were prescribed an initial tapering protocol of PTNS for 3 months and then received ongoing therapy at an individualized frequency as determined by the investigator and subject to maintain sustained improvement in the subjects' OAB symptoms. Questionnaires were completed every 3 months and voiding diaries were completed every 6 months from initial treatment baseline.
RESULTS: Of the 60 subjects eligible to continue, 87% (52/60) enrolled in the STEP Study. Of the 52 subjects, 52 completed 6 months, 49 continued through 9 months and 46 continued to 12 months. The mean number of days between treatments and the mean number of treatments per month by follow up interval is outlined in the table below. Voiding diary parameters at 6 and 12 months were significant for improvement compared to baseline for frequency, incontinence episodes, nighttime voids and moderate to severe urgency episodes.
CONCLUSIONS: Sustained efficacy of PTNS was demonstrated over 12 months following initial success at 12 weeks. Treatment interval frequency results in this study closely mimic those of 12 month outcomes reported in similar trials.
Source: Original Poster