Subgroups of failure after surgery for pelvic organ prolapse and associations with quality of life outcomes: a longitudinal cluster analysis.

Abstract

BACKGROUND\nTreatment outcomes after pelvic organ prolapse (POP) surgery are often presented as dichotomous success or failure based upon anatomic and symptom criteria. However, clinical experience suggests some women with outcome failures are asymptomatic and perceive their surgery to be successful, while others have anatomic resolution, but continue to report symptoms. Characterizing failure types could be a useful step to refine definitions of success, understand mechanisms of failure, and identify individuals who may benefit from specific therapies.\n\n\nOBJECTIVES\nTo identify clusters of women with similar failure patterns over time and assess associations between clusters and the Pelvic Organ Prolapse Distress Inventory (POPDI), Short-Form Six-Dimension health index (SF-6D), patient global impression of improvement (PGI-I), patient satisfaction items questionnaire (PSIQ), and quality-adjusted life years (QALYs).\n\n\nSTUDY DESIGN\nOutcomes were evaluated for up to 5 years in a cohort of participants (N=709) with stage 2 or greater POP who underwent surgical POP repair and had sufficient follow-up in one of 4 multi-center surgical trials conducted by the NICHD Pelvic Floor Disorders Network. Surgical success was defined as a composite measure requiring anatomic success (Pelvic Organ Prolapse Quantification system points Ba, Bp, and C ≤ 0), subjective success (absence of bothersome vaginal bulge symptoms), and absence of retreatment for POP. Participants who experienced surgical failure and attended ≥ 4 visits from baseline through 60 months after surgery were longitudinally clustered accounting for similar trajectories in Ba, Bp, and C, and degree of vaginal bulge bother; missing data were imputed. Participants with surgical success were grouped into a separate cluster.\n\n\nRESULTS\nSurgical failure was reported in 39% (276/709) of the women included in the analysis. Failures clustered into 4 mutually exclusive subgroups: A) asymptomatic intermittent anterior wall failures, B) symptomatic intermittent anterior wall failures, C) asymptomatic intermittent anterior and posterior wall failures and D) symptomatic all-compartment failures. Each cluster had different bulge symptoms, anatomy, and retreatment associations with quality of life outcomes. Asymptomatic intermittent anterior wall failures (N=150) were most similar to surgical successes with Ba values that averaged around -1 cm but fluctuated between anatomic success (Ba ≤ 0) and failure (Ba > 0) over time. Symptomatic intermittent anterior wall failures (N=82) were anatomically similar to asymptomatic intermittent anterior failures but women in this cluster persistently reported bothersome bulge symptoms and the lowest QOL, SF-6D scores, and perceived success. Women with asymptomatic intermittent anterior and posterior wall failures (N=28) had the most severe preoperative POP but the lowest symptomatic failure rate and retreatment rate. Participants with symptomatic all-compartment failures (N=16) had symptomatic and anatomic failure early after surgery and the highest retreatment of any cluster.\n\n\nCONCLUSIONS\nFour clusters of POP surgical failure were identified in participants up to 5 years after POP surgery: asymptomatic intermittent anterior wall failures, symptomatic intermittent anterior wall failures, asymptomatic intermittent anterior and posterior wall failures, and symptomatic all-compartment failures. These groups provide granularity about the nature of surgical failures after POP surgery. Future work is planned for predicting these distinct outcomes using patient characteristics that can be used for counseling individual women.