Stimulation latency and comparison of cycling regimens in women using sacral neuromodulation

In this two-part study, we sought to define how long sacral neuromodulation users with overactive bladder should trial a new setting before attributing symptoms to that setting. Subsequently, we evaluated patient preferences of variable stimulation regimens.

In the initial phase of this prospective pilot study, participants' devices were turned off and later reactivated; time to symptom recurrence and resolution were recorded. In phase two, participants trialed four settings in a masked fashion with random order. After unmasking, participants chose their preferred setting and were followed 1 year.

Twelve subjects completed phase one. With the device off, the mean time to symptom recurrence was 11.25 days. Mean time to symptom regression following reactivation was 6.42 days. Combined, the 90th percentile was 15 days for symptoms to reflect the device's new setting. Among 23 women completing part two, the most popular setting at the time of unmasking was a 1-hr on, 2-hr off cycled setting chosen by 7 (30%) participants. According to published estimates of battery longevity, 14 (61%) participants chose a more energy-conserving setting at the time of unmasking. The mean difference in estimated battery longevity between the chosen and baseline regimens was 14.5 months. These gains diminished in the following year with clinical changes in device settings by patients and providers.

Sacral neuromodulation patients should allow a 2-week trial before attributing symptoms to a new setting. With additional information, many opt for energy-conserving settings. A 1-hr on, 2-hr off regimen warrants further study. Neurourol. Urodynam. 36:486-489, 2017. © 2016 Wiley Periodicals, Inc.