Nocturia

Frequent nighttime urination is a condition known as nocturia. Elderly men often suffer from this condition as a symptom of other diseases, medications being taken or simply because of changes the body undergoes as it ages.

British urologist Lucy Abraham and colleagues note that 60 percent of men in their 70s experience this problem.

How Urination Occurs:
Urine is produced by the kidneys and travels through the ureters to the bladder to be stored. The bladder is a muscular sac that holds urine until it is ready to be released into the urethra, the tube that connects the bladder to the outside of the body. The bladder is emptied when the detrusor muscle, the muscle within the bladder wall, contracts thereby squeezing urine out of the body. At the same time the bladder contracts, the urinary sphincter relaxes. The relaxed sphincter acts like an open door, which allows the urine to pass and exit the body.

Aging Body
As the body ages the bladder muscle becomes less able to hold the amount of liquid that it becomes filled with. It sends messages to the brain that it needs to be emptied more frequently than it used to.

Prostate Cancer
Nocturia is a common symptom of prostate cancer, according to the National Cancer Institute. Other urinary symptoms of prostate cancer are having trouble starting and stopping urination, and having a weak flow.

Type 2 Diabetes
Type 2 diabetes may be the cause of nocturia in older individuals. According to Japanese urologist Koji Yoshimura and colleagues in their study of more than 6,000 subjects, diabetes is a risk factor for nocturia. In addition, they note that individuals aged 70 and older have a six times greater risk for nocturia than individuals aged 49 or younger.

For both men and women there are multiple factors that could cause nocturia including:

-  Behavioral patterns
  -  Diuretic medications
  -  Caffeine
  -  Alcohol
  -  Overactive bladder treatment
  -  Excessive fluids before bedtime

  - Diminished nocturnal bladder capacity- This can be due to decreased functional or nocturnal bladder capacity. Urine production will then exceed the bladder capacity causing the individual to be awakened in order to void.
  - Fluid redistribution- When a person lies down to sleep, fluid is reabsorbed into the blood stream. During the day, gravity causes fluid to accumulate in the body’s lower extremities. When this happens, the kidneys clean the increased fluid in the blood by producing more urine. This leads to excess fluid in legs, ankles, and fingers causing them to swell.

Benign Prostatic Hyperplasia
Benign prostate hyperplasia-BPH-is a common disorder among many older men that is caused by an enlarged prostate. This oversized prostate can put pressure on the bladder and cause nocturia. In a Dutch study by Luba W. Gourova and colleagues of nearly 3,000 men with nocturia, more than half-58.1 percent-were diagnosed with BPH.

Medications May Cause Nocturia
According to California nephrologists Dean A. Kujubu and Sherif R. Aboseif, some medications may cause nocturia, particularly diuretics and calcium channel blockers. They also noted that excessive consumption of alcohol and caffeinated beverage increase the risk for nocturia.

Obesity and Overweight
A study by Finnish urologist Kari A.O. Tikkinen and colleagues found that being overweight or obese increase the risk for nocturia. Among men aged 70 to 79, those with a body mass index equal to or greater than 30 had nearly five times the risk of having nocturia as same-age men with a body mass index of 25 to 29.9.

Summary points

Nocturia, or frequent night time urination, is a common but poorly reported and largely misunderstood urological disorder in adults

Nocturia has a role in numerous aspects of people’s health and wellbeing

Multiple factors may cause nocturia in both men and women

Identifying nocturia, determining its causes, and appropriating effective treatment are keys to improving patients’ quality of life

A complete history and physical examination must be conducted

Treatment options for nocturia depend on the diagnosis and underlying cause(s)

Sacral neuromodulation is a new, minimally invasive surgical technique for patients in whom pharmacotherapy has failed and non-surgical or surgical interventions have proved unsuccessful

Although evidence of its efficacy is preliminary, the procedure has been successfully implemented in numerous patients, notably reducing the degree of urgency and total number of voids

Nocturnal Polyuria
Some patients with nocturia produce large amounts of urine, a condition called nocturnal polyuria. According to nephrologists Dean A. Kujubu and Sherif R. Aboseif, most people produce twice as much urine during the day as at night. But for some people, the nighttime urine volume exceeds the daytime volume.

According to urology professor Serge P. Marinkovic at the Southern Illinois School of Medicine, nocturnal polyuria may be caused by a disruption of vasopressin, an antidiuretic hormone produced by the pituitary gland. Alternatively, it could also be caused by sleep apnea, which can increase the level of water excretion due to elevated concentrations of atrial natriuretic peptide, a diuretic hormone that is secreted by the atrium of the heart.

They recommend sleep studies for those who may have obstructive sleep apnea, especially if they have diabetes, hypertension or asthma. They also note that nocturnal polyuria may be caused by congestive heart failure, and individuals with nocturnal polyuria should receive an echocardiogram and comprehensive medical evaluation.

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By Christine Adamec

Provided by ArmMed Media