SUPINE EMPTY STRESS TEST AS A PREDICTOR OF LOW VALSALVA LEAK POINT PRESSURE

Our objective was to determine whether a positive supine empty stress test is predictive of a low Valsalva leak point pressure (less than or equal to 60 cm of water). Evaluation was carried out on 179 patients with a history of genuine stress incontinence confirmed with urodynami c testing. All patients had a supine stress test performed after voidi ng. Residual urine determinations were all <100 cc. A vesical Valsalva leak point pressure determination (cough and strain) was performed du ring multichannel urodynamics with 150 cc in the bladder. Urethral pro filometry was performed at maximum capacity. There was a statistically significant relationship between a low leak point pressure and a posi tive supine empty stress test (P < 0.000). The supine empty stress tes t had a sensitivity of 79% and a specificity of 62.5% for the detectio n of a low leak point pressure. The negative predictive value was high at 90%. For the age group 50 years and younger the negative predictiv e value was 95%. However, there was no significant relationship betwee n a positive supine empty stress test and a low maximal urethral closu re pressure. We conclude that the supine empty stress test is a useful screening test for a low leak point pressure but not a low urethral c losure pressure. Its high negative predictive value is useful in exclu ding the presence of a low leak point pressure and may help the clinic ian to determine which patients with genuine stress incontinence need further assessment of the dynamic function of the urethral sphincter. (C) 1998 Wiley-Liss, Inc.