Detrusor instability in men: correlation of lower urinary tract symptoms with urodynamic findings

We evaluated the correlation of lower urinary tract symptoms suggestive of detrusor instability with urodynamic findings in men.

Enrolled in our prospective study were 160 consecutive neurologically intact men referred for urodynamic evaluation of persistent lower urinary tract symptoms. All patients had storage symptoms suggestive of detrusor instability. Patients were further clinically categorized according to the chief complaint of urge incontinence, frequency and urgency, nocturia or difficult voiding. The clinical and urodynamic diagnosis in all patients as well as specific urodynamic characteristics of those with detrusor instability were analyzed according to the these 4 clinical categories.

Mean patient age was 61 +/- 15 years. The chief complaint was urge incontinence in 28 cases (17%), frequency and urgency in 57 (36%), nocturia in 30 (19%) and difficult voiding in 45 (28%). Detrusor instability was diagnosed in 68 cases (43%). A higher incidence of detrusor instability was associated with urge incontinence than with the other clinical categories (75% versus 36%, p <0.01). Of the patients 109 (68%) had bladder outlet obstruction, including 50 (46%) with concomitant detrusor instability. The prevalence of bladder outlet obstruction was similar in all patients regardless of the chief complaint. All other urodynamic diagnoses were also similar in the 4 clinical categories. The mean bladder volume at which involuntary detrusor contractions occurred were lower in patients with urge incontinence and frequency and urgency than in those with nocturia and difficult voiding (277.1 +/- 149.4 and 267.7 +/- 221.7 versus 346.7 +/- 204.6 and 306.2 +/- 192.1 ml., respectively, not statistically significant, p = 0.07).

Detrusor instability and bladder outlet obstruction are common in men with lower urinary tract symptoms. The symptom of urge incontinence strongly correlated with detrusor instability. Other lower urinary tract symptoms did not correlate well with any urodynamic findings. Therefore, we believe that an accurate urodynamic diagnosis may enable focused and more efficient management of lower urinary tract symptoms in men.