Desmopressin is an effective treatment for mixed nocturia with nocturnal polyuria and decreased nocturnal bladder capacity

Serum Sodium Alterations in Children with Primary Monosymptomatic Nocturnal Enuresis Using Desmopressin

Background: Hyponatremia/water intoxication has been considered a rare but serious complication of desmopressin (DDAVP) for the treatment of primary monosymptomatic nocturnal enuresis (PMNE). Objectives: This study aimed to identify the incidence and risk factors of serum sodium (Na) alterations in children with PMNE treated with oral or intranasal DDAVP. Methods: A total of 201 patients with PMNE were evaluated in 2 groups using intranasal (n = 127) or oral DDAVP (n = 74) for approximately 6 months. Treatment efficacy was defined as a more than 50% decrease in wet nights after 1 month of treatment. Serum Na was measured before, during, and after treatment in all patients. Predisposing factors of serum Na disturbance were evaluated concomitantly. Results: The mean age of patients was 8.8 ± 2.6 (5 - 17.5) years, and males outnumbered females (M/F = 1.68). Treatment efficacy was 100% in 93 (46.2%), and > 90% in 157 (78.1%) cases. Oral DDAVP had significantly more therapeutic effects than intranasal treatment (P = 0.024). However, serum Na had no significant difference between the 2 groups (P = 0.52). Hyponatremia occurred in 7 (3.5%) patients (3 in oral treatment and 4 in intranasal treatment; P = 0.73) with no significant correlation to age, gender, body weight, frequency of enuresis, and initial serum Na. However, decreased serum Na > 5 mEq/L was a significant risk factor for the prediction of hyponatremia in our patients (P < 0.001). Conclusions: Oral DDAVP had more therapeutic effects than intranasal treatment for the treatment of PMNE. Serum Na had no significant alteration in both oral and intranasal treatments, and hyponatremia was a rare complication of DDAVP, which occurred significantly in children with a > 5-mEq/L decrease of initial serum Na concentration. As a suggestion, monitoring serum Na is not an essential follow-up in asymptomatic patients in DDAVP treatment.

Maladaptation of Renal Hemodynamics Contributes to Kidney Dysfunction Resulting from Thoracic Spinal Cord Injury in Mice

Renal dysfunction is a hallmark of spinal cord injury (SCI). Several SCI sequalae are implicated, however, the exact pathogenic mechanism of renal dysfunction is unclear. Herein, we found that T3 (T3Tx) or T10 (T10Tx) complete thoracic spinal cord transection induced hypotension, bradycardia, and hypothermia immediately after injury. T3Tx-induced hypotension but not bradycardia or hypothermia slowly recovered to levels in T10Tx SCI and uninjured mice ~16 h after injury as determined by continuous radiotelemetry monitoring. Both types of thoracic SCI led to a marked decrease in albuminuria and proteinuria in all phases of SCI, while the kidney injury marker, NGAL, rapidly increased in the acute phase, remaining elevated in the chronic phase of T3Tx SCI. Renal interstitial and vascular elastin fragmentation after SCI were worsened during chronic T3Tx SCI. In the chronic phase, renal vascular resistance response to a step increase in renal perfusion pressure or a bolus injection of Ang II or NE was almost completely abolished after T3Tx SCI. Bulk RNAseq analysis showed enrichment of genes involved in extracellular matrix (ECM) remodeling and chemokine signaling in the kidney from T3Tx SCI mice. Serum levels of interleukin 6 was elevated in the acute but not chronic phase of T3Tx and T10Tx SCI, while serum amyloid A1 level was elevated in both acute and chronic phases. We conclude that tissue fibrosis and hemodynamic impairment are involved in renal dysfunction resulting from thoracic SCI; these pathological alterations, exacerbated by high thoracic-level injury, is mediated at least partly by renal microvascular ECM remodeling.

Effects of vasopressin receptor agonists on detrusor smooth muscle tone in young and aged bladders: Implications for nocturia treatment

PURPOSE

The main goal of this study was to determine the effects of arginine vasopressin (AVP) and desmopressin on bladder contractility and to examine whether the effects of these vasopressin receptor (VR) agonists differ in young versus aged animals. These aims were addressed using urinary bladders from young (3 months) and aged (24 month) female Fischer 344 rats that were isolated and dissected into strips for isometric tension recordings. Bladder strips were exposed to AVP and desmopressin through the perfusate, and tension changes recorded.

RESULTS

In young rat bladders, AVP, an agonist at both vasopressin-1 receptors (V₁Rs) and vasopressin-2 receptor (V₂Rs), concentration-dependently caused contraction of bladder strips with a sensitivity that was greater in young versus aged bladder strips. Removal of the mucosa did not alter the sensitivity of young bladder strips to AVP yet enhanced the AVP sensitivity of aged bladder strips. The differential sensitivity to AVP between young denuded and aged denuded bladder strips was similar. In contrast to AVP, desmopressin (V₂R selective agonist) relaxed bladder strips. This response was reduced by removal of the mucosa in young, but not aged, bladder strips.

CONCLUSION

These findings support a direct role for VRs in regulating detrusor tone with V₁Rs causing contraction and V₂Rs relaxation. In aged bladders, the contractile response to V₁R activation is attenuated due to release of a mucosal factor that attenuates V₁R-induced contractions. Also in aged bladders, the relaxation response to V₂R activation is attenuated by lack of release of a mucosal factor that contributes to V₂R-induced relaxation. Thus age-associated changes in the bladder mucosa impair the effects of VRs on bladder tone. Because the V₂R signaling system is impaired in the older bladder, administering an exogenous V₂R agonist (e.g., desmopressin) could counteract this defect. Thus, desmopressin could potentially increase nighttime bladder capacity through detrusor relaxation in concert with decreased urine production, reducing nocturnal voiding frequency.

Associations between nighttime and daytime maximum voided volumes: Relevance for nocturia?

AIM

The relationship between maximum voided volumes (MVV) during the night and day is poorly understood. Such measurements are important because they are often used to indicate functional bladder capacity (FBC), a relevant parameter for nocturia. This study examined the association of such nighttime and daytime measurements in men with nocturia.

METHODS

We retrospectively analyzed 356 24-hour voiding diaries showing ≥2 nocturnal voids from 220 men at an outpatient urology clinic. We defined small FBC as MVV ≤ 200 mL.

RESULTS

A total of 131 entries demonstrated a nocturnal MVV ≤ 200 mL, of which a majority (98 [74.8%]) also showed a 24-hour MVV ≤ 200 mL (ie, global small FBC), and 33 (25.2%) exceeded the 200 mL threshold during the day (ie, nocturnal-specific small FBC). Correspondingly, among voiding diaries without global small FBC (n = 258), most (225/258 [87.2%]) showed a nocturnal MVV > 200 mL. Data were similar when analyzing only the first complete voiding diary per case, when limiting analyses to those without benign prostatic obstruction, and when limiting analyses to cases with nocturnal polyuria.

CONCLUSION

Nocturia may be attributable to nocturnal-specific small FBC or global small FBC. Although the etiology of nocturnal-specific small FBC remains unclear, it was present in a significant minority of patients with small FBC, thus necessitating more directed research. Conversely, diminished nocturnal MVV was nevertheless relatively uncommon in the absence of global small FBC, such that nocturnal-only voiding diaries may provide a rational alternative for follow-up evaluation in patients with nocturia due to global small bladder capacity.

Desmopressin-Induced Severe Hyponatremia with Central Pontine Myelinolysis: A Case Report

Desmopressin, a synthetic vasopressin analog, is used to treat central diabetes insipidus, hemostatic disorders such as von Willebrand’s disease, and nocturnal enuresis. We present the case of a 69-year-old man who developed severe hyponatremia during treatment with intranasal desmopressin at 10 µg twice daily for chronic polyuria and nocturia thought to be due to central diabetes insipidus. After 5 months of therapy, the patient noticed progressive fatigue, anorexia, dizziness, weakness, light-headedness, decreased concentration, and new-onset falls. At 6 months of therapy, the patient was brought to the emergency department for altered mental status and was found to be severely hyponatremic with a serum sodium level of 96 mmol/L, down from a value of 134 mmol/L at the initiation of therapy. The intranasal desmopressin was discontinued and the patient was admitted to the intensive care unit where the hyponatremia was slowly corrected over the next week to 132 mmol/L, never increasing by more than 8 mmol/L a day, with careful fluid management. This included infusion of over 11 L of 5% dextrose to account for a high urine output, which peaked at 7.4 L in 1 day. However, while the recommended rate for sodium correction was followed, the patient’s magnetic resonance imaging of the brain obtained after discharge displayed evidence of central pontine myelinolysis. Despite this finding, the patient eventually returned to his baseline mental status with no permanent neurologic deficits.

Evaluation and management of patients with nocturia

Nocturia, or awakening one or more times to void at night, becomes clinically significant with two or more voids a night. In the past, nocturia has typically been viewed as a symptom of benign prostatic hyperplasia and/or overactive bladder syndrome. However, newer evidence supports that this is no longer just a symptom but a medical condition that warrants further workup and treatment given its effect on quality of life. The negative effects of nocturia include sleep fragmentation, decreased productivity at work, and increased risk of falls and fractures. A workup to find the underlying cause of nocturia will help guide treatment, which may include pharmacologic agents.

The risk of hyponatremia with desmopressin use for nocturnal polyuria

BACKGROUND

Desmopressin is used for treating nocturnal polyuria, but hyponatremia is an associated concern in the elderly due to impaired urinary dilution. This study was undertaken to characterize hyponatremia occurring in adults using desmopressin for nocturnal polyuria.

METHODS

Data from 172 patients who were prescribed desmopressin for nocturnal polyuria at a urology clinic from September 2010 through February 2013 were retrospectively analyzed. Demographic and laboratory parameters were investigated to examine the risk factors for desmopressin-associated hyponatremia.

RESULTS

The average follow-up serum sodium measured 21 ± 22 days after using desmopressin was 138 ± 5 mmol/l. Hyponatremia (<135 mmol/l) was found in 24 patients (14%), and it was severe in 7 (<126 mmol/l). In the hyponatremic patients, serum sodium decreased by 11 ± 6 mmol/l. Patients with hyponatremia were older than those with normonatremia (78 ± 7 vs. 68 ± 9 years, p < 0.0001). The presence of either hyponatremia-predisposing comorbidities or concurrent medications was associated with hyponatremia. Patients with hyponatremia had lower basal hemoglobin (11 ± 2 vs. 13 ± 2 g/dl, p < 0.001) and serum sodium (139 ± 2 vs. 140 ± 2 mmol/l, p < 0.05) than those with normonatremia. Multivariate logistic regression after adjustment for basal serum sodium showed that advanced age (OR 1.15; 95% CI 1.03-1.27) and lower hemoglobin level (OR 0.64; 95% CI 0.43-0.94) were independently associated with hyponatremia.

CONCLUSION

Hyponatremia is not infrequently associated with desmopressin use. Those with advanced age (≥65 years) and lower hemoglobin are at risk of desmopressin-associated hyponatremia and need to be carefully monitored.

Effect of combined systematized behavioral modification education program with desmopressin in patients with nocturia: a prospective, multicenter, randomized, and parallel study

Purpose

The aims of this study were to investigate the efficacy of combining the systematized behavioral modification program (SBMP) with desmopressin therapy and to compare this with desmopressin monotherapy in the treatment of nocturnal polyuria (NPU).

Methods

Patients were randomized at 8 centers to receive desmopressin monotherapy (group A) or combination therapy, comprising desmopressin and the SBMP (group B). Nocturia was defined as an average of 2 or more nightly voids. The primary endpoint was a change in the mean number of nocturnal voids from baseline during the 3-month treatment period. The secondary endpoints were changes in the bladder diary parameters and questionnaires scores, and improvements in self-perception for nocturia.

Results

A total of 200 patients were screened and 76 were excluded from the study, because they failed the screening process. A total of 124 patients were randomized to receive treatment, with group A comprising 68 patients and group B comprising 56 patients. The patients' characteristics were similar between the groups. Nocturnal voids showed a greater decline in group B (-1.5) compared with group A (-1.2), a difference that was not statistically significant. Significant differences were observed between groups A and B with respect to the NPU index (0.37 vs. 0.29, P=0.028), the change in the maximal bladder capacity (-41.3 mL vs. 13.3 mL, P<0.001), and the rate of patients lost to follow up (10.3% [7/68] vs. 0% [0/56], P=0.016). Self-perception for nocturia significantly improved in both groups.

Conclusions

Combination treatment did not have any additional benefits in relation to reducing nocturnal voids in patients with NPU; however, combination therapy is helpful because it increases the maximal bladder capacity and decreases the NPI. Furthermore, combination therapy increased the persistence of desmopressin in patients with NPU.

Comparison of nocturia response to desmopressin treatment between patients with normal and high nocturnal bladder capacity index

OBJECTIVE

To compare efficacy of desmopressin for treatment of nocturia between patients with normal and high nocturnal bladder capacity index (NBCi).

METHODS

Retrospective analysis of adult patients treated with desmopressin for nocturia. Patients were analyzed according to high or normal NBCi value before treatment.

RESULTS

55 patients were identified, aged 49-84, 47 males, 8 females, who started desmopressin 0.2 mg nocte between 2009 and 2011. Two groups (N: normal and H: high NBCi) were similar regarding number, gender, age, 24 h urine volume, and nocturnal urine volume. On treatment, nocturnal volume decreased by mean of 364 mL. Number of nightly voids decreased in N group from 3.11 to 1.50, in H from 3.96 to 1.44. Nocturnal polyuria and nocturia indices also decreased significantly. NBCi remained the same in N group (0.56 on therapy) and in H group decreased to mean 0.63. All on-treatment values were statistically similar in N and H groups. Pretreatment differences were abolished with treatment. NBCi was significantly correlated to nocturia reduction-larger reduction was observed in patients with higher NBCi. In 8/55 patients, hyponatremia was detected, but without clinical consequences.

CONCLUSIONS

The results indicate that the effectiveness of desmopressin on nocturia is not dependent upon the patient's pretreatment NBCi.