Novel clinical diagnostic criteria based on noninvasive examination findings to predict the presence of urodynamic detrusor underactivity in men

Aims: To investigate the usefulness of novel clinical diagnostic criteria based on noninvasive examination findings to diagnose urodynamic detrusor underactivity (DU) in men. Methods: We developed clinical diagnostic criteria to predict the presence of urodynamic DU in men as follows: (a) bladder voiding efficiency <70% on uroflowmetry, (b) existence of "sawtooth and interrupted waveforms" on uroflowmetry, and (c) ultrasonography-documented intravesical prostatic protrusion <10 mm. We analyzed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of these clinical criteria for diagnosing urodynamic DU in men aged 50 years or above with lower urinary tract symptoms who underwent urodynamic studies. Results: Of the 314 men analyzed (mean age, 72.4 years; mean detrusor contraction index [DCI], 98.8; and mean bladder outlet obstruction index [BOOI], 43.9), 89 men met this clinical DU diagnostic criteria. Of these, 79 men (88.8%) had urodynamic DU (DCI < 100 and BOOI < 40), nine (10.1%) had DU + BOO (DCI < 100 and BOOI >= 40), and one (1.1%) had normal voiding functions. None of the men with urodynamic BOO (DCI >= 100 and BOOI >= 40) met the clinical DU diagnostic criteria. The sensitivity, specificity, PPV, and NPV of these clinical diagnostic criteria for urodynamic DU were 69.3%, 95.0%, 88.8%, and 84.4%, respectively. Conclusion: The proposed clinical DU diagnostic criteria showed a high PPV (88.8%) for diagnosing urodynamic DU. None of the patients with BOO met the clinical diagnostic criteria for DU. These clinical DU diagnostic criteria may be useful in identifying men with urodynamic DU in clinical practice.