Long-Term Effectiveness and Safety of Sacral Neuromodulation With InterStim for Lower Urinary Tract Dysfunction

This is an observational analytical retrospective cohort study with a single cross-sectional follow-up assessment. The study will include adult patients who underwent definitive implantation of the InterStim™ sacral neuromodulation system at Hospital Universitario Fundación Santa Fe de Bogotá between January 1, 2010, and June 30, 2026, for lower urinary tract dysfunction, including overactive bladder, urgency urinary incontinence, non-obstructive acontractile detrusor, and non-obstructive urinary retention.

Eligible patients will be identified consecutively using available institutional sources, including surgical scheduling records, procedure codes, and implantable device records. Data will be obtained from two sources: retrospective review of electronic medical records and a single telephone follow-up assessment.

Medical record review will include sociodemographic and clinical characteristics, indication for sacral neuromodulation, previous treatments, available pre-implantation patient-reported outcome measures, procedural characteristics, perioperative complications, reprogramming, reinterventions, device replacements, explantations, and other events occurring during follow-up.

During the single telephone follow-up, contactable patients who agree to participate will complete the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF), the Patient Global Impression of Improvement (PGI-I), and a 5-point Likert satisfaction scale. Current device status, catheter use, and additional urinary medications will also be recorded.

Effectiveness will be assessed using patient-reported urinary outcomes, including change in ICIQ-UI SF score when a pre-implantation score is available, with a reduction of at least 4 points considered clinically meaningful improvement. The PGI-I will provide an assessment of perceived improvement regardless of the availability of a baseline questionnaire. Additional effectiveness outcomes will include complete continence among patients with overactive bladder or urgency urinary incontinence and catheter independence among patients with non-obstructive urinary retention.

Safety outcomes will include perioperative and postoperative complications, classified according to the Clavien-Dindo classification, as well as reinterventions, device replacement, and surgical explantation. Device outcomes will include the frequency and causes of replacement or explantation and replacement- or explant-free device survival at 1, 3, 5, and 10 years.

Follow-up time will vary according to the date of definitive implantation and will extend from the index implantation date to the telephone assessment for patient-reported outcomes, or to the last available medical record information, definitive explantation, or death, as applicable for safety and device-survival outcomes.