Obesity deserves special mention for its role in causing or exacerbating stress incontinence. Many researchers report an association (that remains after adjusting for age and parity) between increased weight and body mass index (BMI) and urinary incontinence. For example, a dose–response relationship between BMI and severe urinary incontinence was described (30). Compared with women with a BMI less than 25 kg/m2, odds ratios (OR) for the following BMI groups were: 25 to 29, OR 2.0 (range 1.7–2.3); 30 to 34, OR 3.1 (2.6–3.7); 35 to 39, OR 4.2 (3.3–5.3); 40+ 5.0 (3.4–7.3). A prospective randomized study evaluating overweight and obese women with at least 10 urinary incontinence episodes per week undergoing an intensive 6-month weight-loss program versus structured education program found that women in the weight-loss program had a mean weight loss of 8.0% and decreased their leakage episodes by 47% compared to mean weight loss of 1.6% and 28% reduction in leakage episodes in the education program group (31).
Initial Evaluation The initial evaluation of patients with incontinence requires a systematic approach to consider possible causes. The basic evaluation should include the following items: history (including assessment of quality of life and degree of bother from symptoms), physical examination, and simple primary care level tests. Most women can begin nonsurgical treatment after this basic evaluation.
History A thorough medical history should be obtained from every incontinent patient. The history should include a review of symptoms, general medical history, review of past surgery, and current medications. The woman’s most troubling symptoms must be ascertained—how often she leaks urine, how much urine she leaks, what provokes urine loss, what improves or worsens the problem, and what treatment (if any) she had in the past. It is essential to keep the patient’s chief symptom at the forefront to avoid inappropriate management. Consider, for example, a woman whose chief concern is that once a month, while leading a business seminar, she has a sudden, overwhelming urge to void followed by complete bladder emptying. She finds this leakage devastating and is considering quitting her job because of her acute embarrassment. On occasion, she leaks a few drops of urine during exercise, but this minor leakage does not bother her. During the evaluation, urodynamics reveal minimal stress urinary incontinence at capacity during strong coughing. No detrusor overactivity is seen. The patient is offered, and undergoes, a surgical procedure for her documented urodynamic stress incontinence. Not surprisingly, her chief symptom is not improved and she is devastated.
The general medical history may reveal systemic illnesses that have a direct bearing on urinary incontinence, such as diabetes mellitus (which produces osmotic diuresis if glucose control is poor), vascular insufficiency (which can lead to incontinence at night when peripheral edema is mobilized into the vascular system, resulting in increased diuresis), chronic pulmonary disease (which can lead to stress incontinence from chronic coughing), or a wide variety of neurologic conditions that can affect the neurourologic axis at any point from the cerebral cortex to the peripheral nervous system. Medications that may affect the lower urinary tract are summarized in Table 26.3 (32–35).