Introduction 

Nocturia is the need to awaken more than once per night to void (urinate). It is the occurrence of urinary frequency during nighttime sleep. Although nocturia can exist with other symptoms of the lower urinary tract (LUTS), the most common reason is the overproduction of urine at night.

Nocturia is lower urinary tract dysfunction caused by urine overproduction at nighttime. It is called nocturnal polyuria (NP) and is associated with renal and cardiovascular factors.¹ The nocturia can be categorised into two upper urinary tract and lower urinary tract dysfunction. Nocturia has been regarded as one of a range of symptoms related to lower urinary tract symptoms (LUTS), including overactive bladder (OAB) and benign prostatic obstruction (BPO).²

Many people facing nocturia accept it as a part of ageing so do not ask for help. Nocturia is prevalent in older people but impacts a notable fraction of younger individuals as well. A study on 76% of persons assigned female at birth (AFAB) and 69% of persons assigned male at birth (AMAB), aged above 40 reported more than 2 nocturnal voids in the United Kingdom, Sweden, and the United States.²

A significant percentage (4% to 18%) of persons assigned female at birth (AFAB) studied were affected by more than 2 voids/night in their 20s and 30s, while the percentage increased by 28% to 62% in their 70s and 80s. These statistics are almost similar in person assigned male at birth (AMAB) where 2% to 17% of men aged 20-30 years reported more than 2 voids/night rises to 29% to 59% when aged 70-80.² Consequently, nocturia is prevailing in both AMAB and AFAB of all age groups and has profound consequences on the quality of life. In the young population, it causes a rise in morbidity and mortality. Nocturia as a condition deserves public health attention. 

Psychological effects

Nocturia is a bothersome condition that diminishes the quality of life and leads to sleep disturbances, embarrassment, social anxiety, and low self-esteem. Ill health, daytime drowsiness and fatigue, poor concentration, stress, and lack of motivation are other effects.³ This may result in an increased risk of depression, anxiety, and other psychological impacts.¹ However, in depressive individuals the tendency to catastrophize symptoms increases the possibility of bother from urinary symptoms.

Sleep disruption

Sleep is necessary for the physical and mental functioning. However, repeated disruptions caused by nighttime voiding can degrade sleep quality and quantity. The sleep disturbances accompanied by depressive symptoms may cause a person to urinate during the sleep period. It is due to being more often awake, resulting in more frequent urination. It is more prevalent than those encountering abnormal bladder capacity or polyuria as a cause of nocturia.⁶ 

A study in the United States by Sleep Heart Health on 6342 AMAB and AFAB revealed a notable relation between self-reported nocturia and measures of sleep disruption. The sleep measures included sleep efficiency, total sleep time, arousal index, oxygen saturation, and proportion of REM sleep.² Therefore, nocturia is a factor for sleep disturbance, making it the most bothersome Lower urinary tract symptom (LUTS).

Mood disturbances and cognitive impairment

A survey of 20 to 64-year-old participants and 1,948 AMAB and AFAB in Sweden disclosed that urination more than 2 times/night causes poor mental health.¹ It also induces cognitive impairment as reduced concentration, irritability due to improper sleep, and poor memory. 

AMAB with nocturia ≥ 2 times/night are prone to depression 2 times more than that of AFAB with nocturia. In a study conducted on 547 AMAB clinic patients in the US, those with 3 ≥ nocturia events were at considerable risk of depression. Thus, depression and nocturia emerge as frequently comorbid (exist together). Physical health starts to get affected when nocturia frequency is 1, but beyond that mental health becomes evident.

Anxiety and fatigue due to anticipation of night awakenings

A review proposed a bidirectional relevance of nocturia with anxiety and depression. According to the Hospital Anxiety and Depression Scale (HADS), anxiety and depression rise with a rise in the frequency of nocturia and are reported more in AFAB than AMAB.³ Sleep interruptions due to nocturia causes lethargy adversely impacting mood and relationships. It reduces daytime functioning and daily activities initially and diminishes work performance gradually. Nocturia affects productivity, cognitive performance, and quality of life.

Quality of life

Nocturia causes imbalances in mental and physical health and reduces quality of life (QoL). Lethargy and interrupted sleep worsen health conditions. A decline in sleep quality is indirectly related to the factors of poor health associated with nocturia such as diabetes, disturbed glucose homeostasis, and hypertension. 

The association of poor sleep with poor health is not always substantiated. In the elderly population, a direct connection between nocturia and mortality is established based on the observation provided by the Olmsted County Study. This demonstrated a link between nocturia and mortality in men aged 60 years or more. The association of mortality rate with nocturia was likely caused by impaired sleep resulting in risk of falls and fractures in elderly patients of nocturia.¹

Contributing factors

The causes of nocturia are multifactorial. Improper evaluation of underlying reasons results in poor clinical outcomes as the main cause remains unaddressed. Consequently, clinicians or healthcare professionals need to find contributing factors to treat nocturia and address them. 

Medical conditions 

Daytime symptoms increase nocturnal urinary frequency, often due to a reduced bladder storage capacity. In the patients subjected to BPO or OAB medications to treat nocturia, the prime reason for nocturia may not be limited to their enlarged prostate or bladder dysfunction. 

There may be several factors contributing to the overproduction of urine at night. It includes large production of atrial natriuretic peptide(a hormone that helps to regulate blood pressure and water-salt balance) caused by sleep apnea or congestive heart failure, prostate cancer, and abnormalities in the secretion of antidiuretic hormone (arginine vasopressin/AVP).

Thus nocturia may be induced by various other medical conditions such as nocturnal polyuria, sleep disorder, diabetes, decrease in functional bladder capacity, heart disease, high blood pressure, and inflammatory bowel disease. The associated factors and comorbidities linked to nocturia are arthritis, asthma, uterine prolapse, bladder infection, hysterectomy, menopausal status, and prostatitis.³

Psychological disorders

A study demonstrated that nocturia leads to an increase in the odds of reporting depression and depression in the same way increases the possibility of disclosing the results of nocturia. This was evident in Finland where the cases of nocturia and depressive symptoms helped to determine a relationship between nocturia and depressive symptoms.

A group of 1,580 men between 50-70 years old was studied during a 5-year period which reported that antidepressant or antipsychotic medications did not result in a rise in the nocturia incident rate. It was affirmed that untreated depressive symptoms may contribute to nocturia.¹

Other factors- Lifestyle factors (e.g., fluid intake before bed, caffeine consumption)

Some of the other factors contributing to nocturia include:

1. Drinking enough fluid before going to bed
2. Consumption of beverages consisting of alcohol, caffeine, and other diuretic liquids
3. Medications containing diuretics or water pills result in the removal of excess fluid and salt from the body through urination
4. Habit or routine- an unintentional training of the body to wake up to urinate, even if not needed or such other habit

Nocturia thus affecting the quality of life is a result of medical conditions, imbalanced mental health, and other behavioral factors. It widely affects the elderly population and impacts AFAB as well as AMAB has reported. This requires treatment and management to live a better life.

Management and treatment

A review of eight trials/groups of trials for OAB (overactive bladder) treated with antimuscarinics (a type of drug) reported that in trials. The drug did not reduce the number of nocturnal voids.⁴ In other trials, a considerable decline in nocturnal voids was reported. However, its implementation on placebo groups (involved in clinical trials) reduces the nocturnal voids only by 0.2. Consequently, clinicians should consider nocturia to be a major concern and must take steps to unveil the myth that nocturia is a part of ageing. There are various measures to treat or manage nocturia which are: 

Medical interventions

In nocturia, finding and treating the underlying cause is important. In other words, nocturia is caused by sleep apnea. A patient needs a sleep specialist and if prostate enlargement is the reason and medication or surgery for its treatment. It is essential to consult the healthcare provider or clinicians about the treatments that will work best as per the underlying cause. Some of the medications used to treat it include:

• Anticholinergics: These are used to reduce overactive bladder symptoms and 40% of people reported success with their use 
• Diuretics: Such medications aid in the regulation of urine one may produce
• Desmopressin: It helps kidneys to produce less urine

Behavioural strategies

In nocturia, a major cause of concern is the overproduction of urine during nighttime. It may be possible that nocturia does not respond to the treatments used to increase urine flow or bladder capacity leading to a decrease in urgency.⁵ Therefore, the healthcare provider/clinician may suggest certain changes in lifestyle with or without medication to treat nocturia which include:

• Restricting fluid intake in the evening, particularly caffeinated beverages, is a self-treatment
• Taking diuretic medication during the morning or at least six hours before sleep
• Taking naps in the afternoon will allow the bloodstream to absorb liquid
• Adjusting the sleep environment may practise good sleep hygiene or sleep therapy
• Elevation of the legs while sitting at home will help in fluid distribution
• Bladder training exercises or physical therapy like Pelvic floor to strengthen the pelvic floor muscles
• Use therapy or techniques to manage stress, anxiety and depression
• Wearing compression stockings will help with fluid distribution

Other interventions

The prevalence of nocturia and associated reasons, bother the affected population and in some instances, people with nocturia seem reluctant to discuss it. Patients with nocturia look at nocturnal frequency as a part of ageing and thus it remains underreported for many reasons. The role of healthcare providers or clinicians is becoming significant to step up to make people aware of such as:

• Individuals with nocturia or their relatives should consider their condition to be sufficiently serious to consult a healthcare provider
• Dismantle the myths like nocturia is not treatable resulting in not seeking attention for nocturia
• Educate the patients about the facts, symptoms, and complications associated with nocturia to disseminate awareness for its management and available treatments
• Healthcare professionals ask about the symptoms in the elderly who get examined for other illnesses or symptoms

Educating patients and diagnosing underlying reasons reduce its repercussions on quality of life. Efforts to improve related symptoms in patients' health and well-being through behavioural strategies and lifestyle changes would significantly help to reduce the economic burden on the individual and society.

Summary

Nocturia is the most significant reason for sleep disruption. It is accompanied by various negative impacts on psychological health and quality of life for a large proportion of the population. It prevails in AMAB and AFAB of all ages but may get bothersome in younger adults. Here, the repercussions of sleep disturbance become more detrimental to daytime activity and later to health and mortality. The causes of nocturia affect the efficacy of treatment opted to cure it.

The consequences of nocturia are often underestimated by clinicians, leading to failure in proper evaluation of the condition and associated causes. The multifactorial reasons of nocturia, declining health with age, and other comorbidities in such patients may lead to mortality. Greater public health attention to nocturia is therefore needed.