Standing Vs Supine; Does it Matter in Cough Stress Testing?

OBJECTIVES: The aim of this study was to compare the sensitivity of cough stress test in the standing versus supine position in the evaluation of incontinent females.

METHODS: We performed a prospective observational study of women with the chief complaint of urinary incontinence (UI) undergoing a provocative cough stress test (CST). Subjects underwent both a standing and a supine CST. Testing order was randomized via block randomization. Cough stress test was performed in a standard method via backfill of 200 mL or until the subject described strong urge. The subjects were asked to cough, and the physician documented urine leakage by direct observation. The gold standard for stress UI diagnosis was a positive CST in either position.

RESULTS: Sixty subjects were enrolled, 38 (63%) tested positive on any CST, with 38 (63%) positive on standing compared with 29 (28%) positive on supine testing. Nine women (15%) had positive standing and negative supine testing. No subjects had negative standing with positive supine testing. There were no significant differences in positive tests between the 2 randomized groups (standing first and supine second vs. supine first and standing second). When compared with the gold standard of any positive provocative stress test, the supine CST has a sensitivity of 76%, whereas the standing CST has a sensitivity of 100%.

CONCLUSIONS: The standing CST is more sensitive than the supine CST and should be performed in any patient with a complaint of UI and negative supine CST. The order of testing either supine or standing first does not affect the results.