Annoying Nocturia: Causes, Diagnosis & Treatment

What is nocturia?

When a person needs to wake up to urinate more than once during sleep every night, he/she can be defined as suffering from nocturia.

In fact, nocturia is particularly common among the elderly, and their conditions are more severe when compared to other age groups. Literatures show that approximately 50% of adults aged 65 or above need to wake up to urinate at least once every night, and about 24% of them experience two or more nocturia episodes per night. The overall prevalence of nocturia is roughly the same for both genders.

Why is nocturia a problem?

When a patient constantly wakes up to urinate every night, sleep quality is inevitably the primary concern. Due to cumulative sleep deprivation and the habit of nocturia, over 40% of patients with nocturia find it difficult to fall back to sleep after waking up. The more frequent of the problem, the more severe their sleep disturbances.

In view of this, patients who urinate three times or more per night have a significantly higher overall mortality rate than the general population.

Furthermore, obesity, diabetes, depression, and heart disease have also been related to nocturia.

Next is the risk of falls and injuries caused by nocturia. One-fourth of elderly fall during nighttime and among 25% of them are directly related to nocturia. In particular, those who urinate at least twice a night have more than doubled their risk of fractures and fall-related injuries.

Due to these various impacts, patients' quality of life and productivity may decline, which can further lead to exhaustion, mood swings, drowsiness, fatigue, hypersomnia, poor concentration, and cognitive impairment.

Last but not least, since patients with nocturia wake up during nighttime, it can affect their partners' health by disrupting their sleep.  

In short, nocturia causes a wide range of issues, impacting not only the patient's physical and mental health but also the sleep quality of partner. Therefore, it is best for patients to address nocturia and seek medical attention promptly.

Common causes of nocturia

There are four main causes of nocturia, including nocturnal polyuria, global polyuria, bladder storage problems and sleep disorders.

Nocturnal polyuria is the most common cause of nocturia which accounts for up to 88% of the cases.

According to the International Continence Society, nocturnal polyuria is defined as nighttime urine output exceeding certain percentage of the total 24-hour urine output in different age groups. For example, when an adult's nighttime urine output exceeds 20% ​​of the total 24-hour urine output; or for an elderly when his/her nighttime urine output exceeds 33% of the total 24-hour urine output, they are considered to be suffering from nocturnal polyuria. In addition, a decrease in hourly urine output during daytime, resulting in a normal total 24-hour urine output also not uncommon in this group of patients.

There are two main causes of nocturnal polyuria. One is personal habits and preferences, including drinking too much water and soup, caffeinated beverages, excessive alcohol consumption, salty foods, and using diuretics at night. The other is pathological influences, including a decrease in arginine vasopressin (AVP) secretion – an antidiuretic hormone secreted in the posterior pituitary gland, or an increase in atrial natriuretic peptide (ANP) secretion – a diuretic hormone produced by right atrium. These two hormones interact with each other to regulate fluid balance.

As the name implies, global polyuria refers to the daily urine output exceeding a normal range. Normal urine output should be between 1500 and 2000 ml per day; while urine  output reaches 3000 ml or more can be classified global polyuria. Estrogen deficiency, renal insufficiency, diabetes insipidus, diabetes mellitus, medication effects, hypercalcemia, and excessive water intake are the possible causes of global polyuria.

For bladder storage problem, there are various possible causes, including benign prostatic hyperplasia, overactive bladder, irradiation effects, non-infectious cystitis, bladder stones, urinary tract infection, urinary retention, atrophic vaginitis, alcohol, caffeine, and anxiety, which will not be discussed here in details.

On the other hand, if a patient is unable to return to sleep quickly after nocturnal urination, or complains of morning fatigue, he/she may possibly suffer from sleep disorder related nocturia.

In general, since the causes of nocturia are complex, urologist will assess the patient from multiple aspects before making a conclusive diagnosis.

How to diagnose nocturia?

To diagnose nocturia, urologist firstly reviews a patient's medical history and daily life styles, such as urination symptoms, drinking habits, caffeine and alcohol intake, sleep habits, and dietary habits (particularly those high in sodium). Past medical history, especially history of hypertension, heart disease, heart failure, diabetes, and use of diuretics and beta-blockers, is crucial.

Urologist will also conduct a physical examination to identify the cause. These include an abdominal examination to evaluate different urinary problems (such as overdistended bladder or high post-void residual volume); an auscultatory examination to determine if the nocturia is related to cardiac problems (for example, looking for signs such as crackles, shortness of breath, tachycardia, and dyspnea); an examination of the lower extremities to look for edema; and, for male patients, a per rectal examination to rule out prostate problem.

Besides, patients may need to keep a 24-hour voiding diary to record the daily fluid intake, urination frequency and volume in order to monitor daily body's fluid balance.

In addition, urologist will arrange investigations such as uroflowmetry, urodynamic study, flexible cystoscopy and prostate cancer screening for patients if need to further confirm the diagnosis.

Treatment options for nocturia

When is nocturia considered an pathological issue? Most people do not recognize this is an issue until their sleep is significantly disrupted. However, when nocturia reaches two or more times per night and becomes bothersome, it is considered pathological and requires treatment.

There are three main types of treatment options for nocturia, which includes lifestyle changes, physiotherapy, and medical treatment.

For lifestyle modification, the first thing to pay attention to is eating habits. These include: limiting the total daily fluid intake to two liters per day, or reducing your usual water intake by 25%; limiting water intake in the afternoon and evening, especially between dinner and bedtime, and avoiding drinking water 2 to 3 hours before bedtime. Avoiding tea, coffee and alcoholic beverages in the evening, and reducing salt and protein intake in the diet especially during dinner.

Secondly, it's important to change the habits of medication intake, especially for long-term diuretic users. For example, taking the medication in the early afternoon allows diuretic effects to end before bedtime. If a diuretic is taken twice daily, the evening dose should ideally be taken at around 3:00 PM, 6 to 8 hours before bedtime, to minimize nighttime urination. It's also recommended to take the nighttime medication with only a sip of water.

Patients should also avoid standing for long periods during the day and keep their lower limbs elevated after dinner to reduce lower limbs edema. Besides, patients can wear compression stockings if needed.

In addition, patients should establish regular sleep habits to improve sleep quality. For example, avoid naps after 3 p.m., minimize the use of electronic device before bed, optimize bedroom environment, and avoid excessive thinking during sleep. Patients are also encouraged to exercise more during daytime. Patients should quit smoking to prevent nicotine from interfering with sleep quality.

To reduce the risk of falls caused by nocturia, patient should consider to place a urinal next to the bed, remove any obstructions, loose rugs or furniture on the way between the bed and the toilet, and install a nightlight to illuminate the path to the toilet.

Physiotherapy aims to strength the pelvic floor muscle (also known as Kegel exercises) in order to improve incontinence and frequency caused by overactive bladder.

For patients experiencing nocturia due to conditions such as benign prostatic hyperplasia (BPH), overactive bladder, menopausal symptoms, sleep disorders, and hormonal deficiencies, urologist may prescribe medications to improve the conditions.

Overall, nocturia and its problems are diverse and distributing. If it is not treated early, it could turn out to be a continuous irritable topic for both the patients and their partners. Therefore, patients should seek medical attention promptly to preserve their quality of life.

Reference:

• Herschorn, S., Gajewski, J., Schulz, J., & Corcos, J. (2007). A population‐based study of urinary symptoms and incontinence: the Canadian Urinary Bladder Survey. BJU International, 101(1), 52–58. https://doi.org/10.1111/j.1464-410x.2007.07198.x
• Prince, D., Pedler, K., & Rashid, P. (2012). Nocturia--a guide to assessment and management. PubMed, 41(6), 399–402. https://pubmed.ncbi.nlm.nih.gov/22675680

> If you have any questions or concerns, please feel free to schedule a consultation appointment with our surgeons.