[Urodynamic phenomena in the aging bladder]

Are there different patterns of detrusor overactivity which are clinically relevant? ICI-RS 2018

INTRODUCTION

Different patterns of detrusor overactivity (DO) have been described and included in several standardization terminology documents. However, it is unclear if these different patterns have any clinical significance.

METHODS

This is a report of the proceedings of Proposal 3: "Are there different patterns of detrusor overactivity which are clinically relevant?" from the annual International Consultation on Incontinence-Research Society (ICIRS) meeting, which took place from 14 to 16 June 2018, in Bristol, UK.

RESULTS

We have collected and discussed, as a committee, the evidence about different urodynamic (UD) patterns of detrusor overactivity and their potential clinical significance. We reviewed the important previous basic research and clinical studies and compiled summaries. The discussion focused on clinical relevance of different UD patterns of DO and what further research is required.

CONCLUSIONS

There are several UD definitions of patterns of detrusor overactivity, however the clinical relevance of these definitions remains unclear. Future research should concentrate on defining the pattern of DO in relation to clinical diagnosis, gender, age, and treatment outcomes.

Urodynamic Investigation: A Valid Tool to Define Normal Lower Urinary Tract Function?

Objectives

To evaluate whether urodynamic investigation (UDI), the gold standard to assess refractory lower urinary tract symptoms (LUTS), is appropriate to select healthy volunteers with apparent normal lower urinary tract function as control subjects for comparative studies.

Subjects and Methods

42 healthy subjects (22 women, mean age 32±10 years; 20 men, mean age 37±12 years) without LUTS were included into this prospective single-centre cohort study. All subjects recorded a 3-day bladder diary, completed validated questionnaires regarding LUTS, and underwent neuro-urological assessment as well as free uroflowmetry. Same session repeat UDI was performed according to “Good Urodynamic Practice” recommended by the International Continence Society, but using an air-charged instead of a water-filled catheter, and evaluated by a blinded investigator.

Results

All 3-day bladder diaries, LUTS questionnaires, neuro-urological assessments and free uroflowmetries were within normal limits. Overall (either during the first or second UDI), same session repeat UDI revealed pathological findings in 71% (30/42): Detrusor overactivity was detected in 14% (3/22) and 30% (6/20), post void residual >100mL in 14% (3/22) and 25% (5/20), bladder outlet obstruction in 9% (2/22) and 20% (4/20) and detrusor sphincter dyssynergia in 77% (17/22) and 65% (13/20) of our women and men, respectively.

Repeatability of detrusor overactivity (κ = 0.78, 95% CI: 0.54–1.02) and detrusor sphincter dyssynergia (κ = 0.77, 95% CI: 0.55–0.98) showed substantial agreement between both UDIs. All other assessed urodynamic parameters had wide 95% limits of agreement for differences in the parameters indicating poor repeatability.

Conclusions

More than 70% of our healthy subjects showed pathological urodynamic findings. Although UDI is the gold standard to assess refractory LUTS, it seems not to be applicable in healthy subjects to define normal lower urinary tract function. Therefore, we do not recommend using UDI to select healthy control subjects.

Safety and efficacy of desmopressin for the treatment of nocturia in elderly patients: a cohort study

PURPOSE

Desmopressin is used widely to treat nocturnal polyuria (NP), but there is concern of hyponatremia especially in elderly patients. This study aimed to evaluate the safety and efficacy of long-term desmopressin treatment in elderly patients with NP.

METHODS

Patients who were ≥65 years old with NP were analyzed. All patients were started on 0.1 mg desmopressin, and the dose was escalated to 0.2 mg depending on patient symptoms. All patients were educated the mechanism of desmopressin. The voiding diary and serum sodium levels were evaluated at baseline, 3-7 days after starting treatment and every 3-6 months. Safety was evaluated by hyponatremia, hyponatremic symptoms and other adverse drug events. The mean changes in number of nocturia and nocturnal urine volume (NUV) were evaluated for efficacy.

RESULTS

A total of 68 patients were included. The mean age was 72.6 (66-85) years. The mean night-time frequency was 3.0 ± 1.8 day, and the mean serum sodium level was 141.2 ± 2.1 mEq/L at baseline. The mean follow-up period was 27.9 months. The mean decrease in serum sodium level was 1.3 ± 3.4 mEq/L at the last follow-up (p = 0.003). Hyponatremia incidence was 4.4 %, and all patients recovered by stopping medication. Severe adverse events were not observed. The mean night-time frequency had decreased by 2.1, and the NUV had decreased by 374.2 ± 261.3 mL at the last follow-up (p < 0.001).

CONCLUSIONS

Desmopressin at doses below 0.2 mg is safe and effective in elderly patients with NP if patients are well informed and are closely followed up.

Alteration in contractile responses in human detrusor smooth muscle from obstructed bladders with overactivity

INTRODUCTION

In this study, we aimed to evaluate changes in contractile responses under in vitro conditions in detrusor overactivity (DO) in patients with bladder outflow obstruction (BOO).

MATERIALS AND METHODS

Detrusor strips obtained during open prostatectomy procedure from 16 patients with BOO related to benign prostate hyperplasia were evaluated under in vitro conditions. Patients were assigned to two groups as patients with (DO) and without (no DO) DO. Four detrusor strips were prepared from each bladder in dimensions of 2 x 10 mm, and were suspended in organ bath. Responses to carbachol (10(-8) to 10(-3)M), electrical field stimulation (EFS) (0.5-32 Hz), single-dose adenosine 5'-triphosphate (ATP) (10(-3)M) and KCl (120 mM) were recorded to evaluate the contractile responses. EFS responses were repeated in the presence of NG-nitro-L-arginine methyl ester (L-NAME; 10 muM) and L-NAME + indomethacin. All responses were expressed as mg tension developed per mg of bladder tissue. Data obtained were compared using independent t test and one-way ANOVA test. Values of p < 0.05 were accepted as statistically significant.

RESULTS

Of the 16 patients on whom open prostatectomy was performed because of BOO, 8 of the patients were determined as no DO and 8 as DO. There were no differences between groups regarding age and residual urine. We found statistically significant differences between groups regarding dimensions of prostate, maximum bladder capacity and maximum bladder pressure. In the comparison of cumulative dose of carbachol, it was seen that responses were higher in the DO group, but the differences were not statistically significant. In EFS application, contractile responses were found to increase significantly in the DO group. No changes were observed between groups for ATP and KCl. EFS responses were found to be significantly higher in presence of L-NAME + indomethacin in the no DO group; however, no difference was seen in the DO group.

CONCLUSIONS

Detrusor contractile responses to EFS increased in patients with BOO in presence of overactivity. These changes in contractile responses are observed possibly as a result of deterioration in neuromodulation, rather than as a result of changes in purinergic or cholinergic receptor sensation or level. We suggest that a noncholinergic-nonpurinergic mechanism can have some effect on these changes.

Clinical observations of the effect of antidiuretic hormone on nocturia in elderly men

OBJECTIVE

To evaluate the effect of desmopressin on nocturia, based on patients' subjective scoring of nocturia, as desmopressin is widely used to treat nocturnal enuresis and nocturnal polyuria.

PATIENTS AND METHODS

We investigated a specific subgroup of 28 men with benign prostate obstruction and nocturia who were treated with desmopressin. Patients with nocturnal polyuria were excluded. All the patients were refractory to treatment with antimuscarinics or anticholinergics, e.g. oxybutynin, tolterodine, and propantheline bromide. We assessed the effect of desmopressin using a quantitative nocturia score and analysed its synergistic effect with alpha-blockers.

RESULTS

The mean frequency of nocturia was 6.1 before desmopressin and most (86%) patients had an improvement in nocturia within 1-12 weeks of treatment with desmopressin. There was a 43% reduction in nocturia after using desmopressin (P < 0.001). The correlation coefficient between the number of nocturnal voids and the reduction in nocturia after treatment with desmopressin was 0.756, indicating that the more severe the nocturia, the more effective was desmopressin.

CONCLUSIONS

Desmopressin is effective for refractory nocturia in elderly men with no nocturnal polyuria, and has limited side-effects.