Validity of Utility Measures for Women with Pelvic Organ Prolapse

Pelvic organ prolapse is a common condition that frequently co-exists with urinary and fecal incontinence. The impact of prolapse on quality of life is typically measured through condition-specific quality of life instruments. Utility preference scores are a standardized generic health related quality of life (HRQOL) measure that summarizes morbidity on a scale from 0 (death) to 1 (optimum health). Utility preference scores quantify disease severity and burden and are widely used in cost-effectiveness research. The validity of utility preference instruments in women with pelvic organ prolapse has not been established.

The objective of this study was to evaluate the construct validity of generic quality of life instruments for measuring utility scores in women with pelvic organ prolapse. Our hypothesis was that women with multiple pelvic floor disorders would have worse (lower) utility scores than women with pelvic organ prolapse only and that women with all three pelvic floor disorders would have the worst (lowest) utility scores.

This was a prospective observational study of 286 women with pelvic floor disorders from a referral female pelvic medicine and reconstructive surgery practice. All women completed the following general health-related quality of life questionnaires: Health Utilities Index Mark 3, EuroQol, and Short Form 6D and a visual-analogue scale. Pelvic floor symptom severity and condition specific quality of life were measured using the Pelvic Floor Distress Inventory and Pelvic Floor Impact Questionnaire, respectively. We measured the relationship between utility scores and condition-specific quality of life scores and also compared utility scores between four groups of women: 1) pelvic organ prolapse only, 2) pelvic organ prolapse and stress urinary incontinence, 3) pelvic organ prolapse and urgency urinary incontinence, and 4) pelvic organ prolapse, urinary incontinence and fecal incontinence.

Of 286 women enrolled, 191 (67%) had pelvic organ prolapse, mean age was 59 and 73% were Caucasian. Among women with prolapse, 30 (16%) also had stress urinary incontinence, 39 (20%) had urgency urinary incontinence and 42 (22%) had fecal incontinence. For the Health Utilities Index Mark 3, EuroQol, and Short Form 6D, the pattern in utility scores was noted to be lowest (worst) in the prolapse + urinary incontinence + fecal incontinence group (0.73-0.76), followed by the prolapse + urgency urinary incontinence group (0.77-0.85) and utility scores were the highest (best) for the prolapse only group (0.80-0.86). Utility scores from all generic instruments except the visual analog scale were significantly correlated with the Pelvic Floor Distress Inventory and Pelvic Floor Impact Questionnaire total scores (r-values -0.26 to -0.57), and prolapse, bladder, and bowel subscales (r-values -0.16 to -0.50). Utility scores from all instruments except the visual analog scale were highly correlated with each other (r = 0.53 to 0.69, p <0.0001).

The Health Utilities Index Mark 3, EuroQol, and Short Form 6D, but not the visual analogue scale, provide valid measurements for utility scores in women with pelvic organ prolapse and associated pelvic floor disorders and could potentially be used for cost-effectiveness research.

American journal of obstetrics and gynecology. 2017 Oct 05 [Epub ahead of print]

Heidi S Harvie, Daniel D Lee, Uduak U Andy, Judy A Shea, Lily A Arya

Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine., Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine. Electronic address: ., Department of Medicine, University of Pennsylvania School of Medicine.