Program to Reduce Incontinence through Diet and Exercise (PRIDE)

Background
Obesity is an established and modifiable risk factor for urinary incontinence, but conclusive evidence for a beneficial effect of weight loss on urinary incontinence is lacking.

Methods

We randomly assigned 338 overweight and obese women with at least 10 urinary incontinence episodes per week to an intensive 6-month weight-loss program that included diet, exercise, and behavior modification (226 patients) or to a structured education program (112 patients).

Results

The mean (±SD) age of the participants was 53±11 years. The body-mass index (the weight in kilograms divided by the square of the height in meters) (36±6) and the weekly number of incontinence episodes as recorded in a 7-day diary of voiding (24±18) were similar for both groups at baseline. The women in the intervention group had a mean weight loss of 8.0% (7.8 kg), as compared with 1.6% (1.5 kg) in the control group (P<0.001). After 6 months, the mean weekly number of incontinence episodes decreased by 47% in the intervention group, as compared with 28% in the control group (P = 0.01). As compared with the control group, the intervention group had a greater decrease in the frequency of stress-incontinence episodes (P = 0.02), but not of urge-incontinence episodes (P = 0.14). A higher proportion of the intervention group than of the control group had a clinically relevant reduction of 70% or more in the frequency of all incontinence episodes (P<0.001), stress-incontinence episodes (P = 0.009), and urge-incontinence episodes (P = 0.04).

Conclusions

A 6-month behavioral intervention targeting weight loss reduced the frequency of self-reported urinary-incontinence episodes among overweight and obese women as compared with a control group. A decrease in urinary incontinence may be another benefit among the extensive health improvements associated with moderate weight reduction. (ClinicalTrials.gov number, NCT00091988.)
Methods
Eligible participants were randomly assigned at a 2:1 ratio to an intensive 6-month behavioral weight-loss program or to a structured four-session education program (the control group). Randomization
was performed with the use of randomly permuted blocks of three or six, stratified according to clinical center, with random assignment concealed in tamper-proof envelopes. The participants were aware of their treatment assignment, but the staff members who collected the outcome data were not.

The participants completed questionnaires concerning their demographic characteristics, medical and behavioral history, and history of incontinence that were routinely used by the investigators.

The participants were weighed to the nearest 0.5 kg on a calibrated digital scale (Tanita BWB 800) while wearing street clothes and without shoes. Height was measured at baseline to the nearest centimeter with the use of a calibrated, wall-mounted stadiometer and a horizontal measuring block.

The participants were trained to complete a 7-day diary of voiding (see the Supplementary Appendix, available with the full text of this article at NEJM.org), and interviewers reviewed the diaries with the participants to answer questions and reconcile inconsistencies.15,16 The participants recorded the time of each void and each incontinence episode. According to the instructions provided, the participants identified each episode as stress incontinence (involuntary loss of urine with coughing, sneezing, straining, or Weight Loss to Treat Urinary Incontinence n engl j med 360;5 nejm.org january 29, 2009 37 exercise), urge incontinence (loss of urine associated with a strong need or urge to void), or other. For the purposes of analysis, each woman was then classified as having stress-only incontinence, stress-predominant incontinence (i.e., at least two thirds of the total number of episodes were stress episodes), urge-only incontinence, urge-predominant continence (i.e., at least two thirds of the total number of episodes were urge episodes), or mixed incontinence (i.e., at least two types were reported, but no type constituted two
thirds of the total number of episodes).

背景 肥胖已被证实为尿失禁的可干预危险因素，但目前仍缺乏体重减轻对尿失禁具有有益影响的确凿证据。

方法 本研究将338名每周至少出现10次尿失禁发作的超重及肥胖女性，随机分配至为期6个月的强化减重干预组（包含饮食控制、运动及行为矫正，共226例），或结构化健康教育对照组（共112例）。

结果 受试者的平均年龄（±标准差）为53±11岁。基线时，两组的体重指数（即体重千克数除以身高米数的平方，36±6）以及7天排尿日记记录的每周尿失禁发作次数（24±18）均无显著差异。干预组受试者的平均体重下降幅度为8.0%（折合7.8kg），对照组仅为1.6%（折合1.5kg）（P<0.001）。干预6个月后，干预组的每周平均尿失禁发作次数较基线下降47%，对照组则下降28%（P=0.01）。与对照组相比，干预组的压力性尿失禁发作频率下降更显著（P=0.02），但急迫性尿失禁发作频率无明显差异（P=0.14）。干预组中，尿失禁总发作频率较基线下降70%及以上且具有临床意义的受试者占比显著高于对照组（P<0.001），压力性尿失禁发作频率下降70%及以上且具有临床意义的占比也更高（P=0.009），急迫性尿失禁发作频率下降70%及以上且具有临床意义的占比同样如此（P=0.04）。

结论 与对照组相比，为期6个月的以减重为目标的行为干预，可降低超重及肥胖女性自我报告的尿失禁发作频率。适度减重带来的诸多健康获益中，尿失禁症状改善或许是其中一项额外益处。（本研究注册于ClinicalTrials.gov，编号NCT00091988。）

方法 符合入组标准的受试者以2:1的比例被随机分配至为期6个月的强化行为减重干预组，或结构化四课时健康教育对照组。随机分组采用按临床中心分层的3或6个单位的随机区组设计，分组信息隐藏于防拆封信封中。受试者知晓自己的分组情况，但收集结局数据的研究人员并不知情。
受试者填写研究人员常规使用的问卷，内容涵盖人口统计学特征、病史与行为史以及尿失禁病史。
受试者身着日常衣物、脱鞋，使用校准后的数字化体重秤（"Tanita BWB 800"）测量体重，精度可达0.5kg。基线身高测量采用校准后的壁挂式身高计与水平测量块，精度可达1cm。
受试者接受培训以完成7天排尿日记（详见补充附录，可在NEJM.org获取本文全文及附录），访员会与受试者一同审核日记，解答疑问并修正不一致之处15,16。受试者需记录每次排尿及每次尿失禁发作的时间。根据研究指南，受试者需将每次发作归类为压力性尿失禁（咳嗽、喷嚏、用力或运动时出现不自主漏尿）、急迫性尿失禁（伴随强烈排尿冲动时出现漏尿）或其他类型。为便于分析，每位女性被分为以下类别：单纯压力性尿失禁、压力性为主型尿失禁（即压力性发作占总发作次数的三分之二及以上）、单纯急迫性尿失禁、急迫性为主型尿失禁（即急迫性发作占总发作次数的三分之二及以上），以及混合性尿失禁（即存在至少两种类型的发作，但任一类型占比均不足总发作次数的三分之二）。