How do we diagnose detrusor underactivity? Comparison of diagnostic criteria based on an urodynamic measure

Abstract

PurposeTo compare several contemporary urodynamic criteria for diagnosing detrusor underactivity (DU) and estimate how well they coincide with each other.Materials and MethodsFrom our prospective urodynamic database we identified nonneurogenic lower urinary tract symptoms (LUTS) patients older than 60 years between 2003 and 2014. Patients were reclassified based on four and three contemporary criteria for DU among men and women. Each criterion was compared with the others using the McNemar test.ResultsUrodynamic data of 4,372 patients (3,357 men and 1,015 women) were analyzed. In men, the prevalence of DU was estimated to be 56%, 17%, 5%, and 10% based on bladder contractility index, Abrams-Griffith number, maximal detrusor pressure at maximal flow rate (PdetQmax) 30, and bladder voiding efficiency (BVE) criteria. In women, 14.9%, 9.6%, and 6.4% of patients were classified as having DU based on maximal flow rate/postvoid residual (Qmax/PVR), PdetQmax 30, and BVE criteria. For individual subjects, all 4 criteria for men were significantly different from each other, while PdetQmax 30 and BVE criteria for women did not differ significantly (p=0.065). Additionally, BVE criterion for men and PdetQmax 30 and BVE criteria for women could distinguish the differences of patient age, free Qmax and free PVR between patient with and without DU.ConclusionsEach urodynamic criterion for men does not coincide with each other in the diagnosis of DU within individual subjects. On the other hand, PdetQmax 30 criteria and BVE criteria for women could be appropriately applied to clinical practice when diagnosing DU in women with LUTS.

<p>The Prevalence of Detrusor Underactivity and its Symptoms Co-relation with Urodynamic Study Findings in Patients with Lower Urinary Tract Symptoms</p>

“…22 Medical treatment has been given to the majority of the patients, which might be reflected with missed diagnosis due to the long duration of the prevalent problem and overlap of DU characteristics with other common symptoms such as bladder overactivity, urinary tract infections, and BOO. 23,24 The findings of the current study are supported by the findings of Rademakers et al, 25 who reported a prevalent increase of hesitancy, weak stream, and incomplete bladder emptying in women with DU as compared to men.…”

The role of urodynamics in females with lower urinary tract symptoms

“…The only definitive finding that is confirmed is the presence of an acontractile detrusor muscle, where there is no detrusor pressure recorded during voiding and the patient will void by straining only [1]. Other parameters that were discussed to assess such patients included: P det Q max <30 cmH 2 O, Q max <10 mL/s, and a bladder voiding efficiency (which is voided volume divided by voided volume plus PVR and <90% is suggestive of detrusor underactivity), reduced maximum cystometric capacity, and impaired compliance [47,48]. Therefore, UDS is important in such patients.…”

Underactive bladder in aging rats is associated with a reduced number of serotonin‐expressing cells in the urethra and is improved by serotonin application to the urethra

“…In humans, a correct diagnosis of DU is only possible by pressure flow studies that require the simultaneous measurement of detrusor pressure and urine flow . However, a recent study showed a good correlation between pressure flow studies and BVE in women . Moreover, a BVE <60% is commonly used to define DU .…”

“…16 However, a recent study showed a good correlation between pressure flow studies and BVE in women. 17 Moreover, a BVE <60% is commonly used to define DU. 18 Therefore, we believe that the BVE of 48% in the aged female rats used in this study is a robust indicator of DU.…”