Nocturia: Symptom or Disease?

by Sep 2018Nocturia

Matt T. Rosenberg, MD, presented “Nocturia: Symptom or Disease?” during the 19th Annual Future Directions in Urology Symposium on August 11, 2018 in Colorado Springs, Colorado.

How to cite: Rosenberg, Matt T. “Nocturia: Symptom or Disease?” August 11, 2018. Accessed [date today]. https://grandroundsinurology.com/nocturia-symptom-or-disease

Nocturia: Symptom or Disease? – Summary

Matt T. Rosenberg, MD, discusses the multiple etiologies of nocturia and nocturnal polyuria and corresponding treatment options, emphasizing the need for shared care when managing nocturia. He then reviews the efficacy and safety of a novel version of desmopressin for reducing the kidney’s production of urine at night time.

To further expand your knowledge of the management of nocturia, visit the Nocturia Next Generation Learning Center.

The Quality of Life Burden of Nocturia and Nocturnal Polyuria

The International Continence Society defines nocturia as waking at night to urinate, with each voiding episode preceded and followed by sleep. Urologists consider waking to void twice or more per night to be clinically relevant nocturia. Nocturnal polyuria, while similar to nocturia, refers to nighttime urine production greater than 20% of the total urine volume output for younger adults, and greater than 33% for older adults.

Although the prevalence rate of nocturia is high, not everyone with symptoms chooses to receive treatment. Even so, nocturia poses a high burden to patients. Sleep deprivation associated with nocturia can lead to productism problems and absenteeism. For the elderly population, waking to void at night poses an increased risk of falling and fractures.   

Evaluating the Causes of Nocturia

Nocturia is a multifactorial condition. Benign prostatic hyperplasia (BPH) can obstruct the bladder’s ability to empty completely, leading to a shortened filling time, and as a result, cause the patient to void more frequently at night. Similarly, overactive bladder (OAB) and small bladder capacity can lead to nighttime urination. Additionally, patient’s symptoms may be due to unrelated sleep disorders in certain cases.

Dr. Rosenberg emphasizes the idea that despite the frequency or cause of nocturia, physicians should select patients to treat based on degree of bother.

The Multiple Etiologies of Nocturnal Polyuria

Dr. Rosenberg categorizes the etiologies of nocturnal polyuria into overconsumption, overdiuresis, and too little antidiuresis.

Oftentimes, patients will habitually drink water before or during the nighttime. Patient counseling can address this issue. Overconsumption can also be a challenge for patients with dipsogenic diabetes insipidus or diabetes mellitus. Patients can experience overdiuresis due to third-space fluid absorption, diuretic medications, renal conditions, and congestive heart failure. Lack of antidiuretic hormone attributes to nocturia, as well.

Nocturia Treatment Options

Dr. Rosenberg advises physicians to first address any behavioral patterns or separate factors a patient might have when treating a patient with nocturia. For example, consider alpha blockers, 5α-Reductase inhibitors (5-ARIs), or phosphodiesterase type 5 (PDE5) inhibitors for treating BPH, antimuscarinics or beta-3 adrenergic receptor agonists for treating OAB, and refer patients to seek care from a sleep clinic for any sleep disorders they may have.

Desmopressin: Pausing Urine Production in the Kidney

In certain cases, however, it is necessary to directly treat patients for nocturnal polyuria due to a lack of antidiuresis. Dr. Rosenberg explains that the mechanism of action for desmopressin is to increase water absorption in the distal tubule and collecting ducts, therefore decreasing nocturnal polyuria. This does not change the total volume of urine created over a 24-hour period, but instead pauses the production of urine for a small number of hours.

Unfortunately, traditional desmopressin formulations have an associated risk of hyponatremia. However, desmopressin acetate nasal spray (DANS), a novel version of desmopressin, has a high bioavailability that allows for low dosing and a short antidiuretic effect that lasts 4-6 hours. Data shows that DANS effectively decreases the volume of urine the kidney produces at night. Accordingly, this decreased urine production leads to decreased bladder filling and events of waking at night to void.
Dr. Rosenberg reviews clinical trials suggesting that DANS has a relatively low risk of hyponatremia, as well as the contraindications, warnings, and precautions for the drug. He also advises physicians to monitor patients’ sodium levels prior to initiating DANS treatment, on day 7, on day 30, and then periodically after treatment as clinically appropriate.

Which Specialty is in Charge of Urine?

Dr. Rosenberg adequate management of nocturia requires shared care. Urologists should investigate to determine if a patient’s symptoms originate from the prostate or the bladder, while primary care physicians should investigate the kidneys. Urologists and primary care physicians also must work together in general to safely treat and monitor this condition.