Urodynamic characterisation of women with naive urinary incontinence: a population-based study in subjectively incontinent and healthy 53-63 years old women

OBJECTIVES: To compare the urodynamic characteristics in a group of middle-aged women with untreated urinary incontinence with the findings in a control group of healthy women. METHODS: Sixty women with mild-to-moderate urinary incontinence and 28 symptom-free women, 53-63 years old, were randomly chosen out of a large health questionnaire study. All were investigated with a detailed history, gynaecological examination, urinalysis, frequency-volume chart, and urodynamics including cystometry and pressure-flow analysis. RESULTS: The maximum urinary flow was significantly higher in the incontinent group of women, 22+/-1ml/s, than in the healthy controls, 16+/-2ml/s (p<0.01). The acceleration of flow, with a theoretical maximum of 0 degrees, was also significantly faster in the incontinent, 20 degrees, than in the healthy women, 32 degrees (p=0.01). In the five women with urge incontinence only, maximum urinary flow was 26+/-2.4ml/s and the flow acceleration 7 degrees. In incontinent women, both a lower opening pressure and detrusor pressure at maximum flow were seen compared with the healthy women, though the difference did not reach statistical significance. The incontinent and the healthy women did not differ regarding bladder volumes or pressures during filling. CONCLUSION: The findings of this study indicate the presence of an increased efficiency of the urethral opening mechanism in incontinent women compared to normal, irrespective of the type(s) of symptoms present.