Frequent toilet trips at night linked to higher risk of mortality

SINGAPORE - Having to get up two or more times during the night to urinate may seem simply like an inconvenience but it may be a sign that something is wrong.

This problem of having to make frequent trips to the toilet at night is a growing one, affecting more people as the population here ages.

Recent research shows that a man who wakes up two or more times each night to urinate, a symptom called nocturia, is 1.49 times more likely to die earlier than a man who wakes up only once or not at all.

Similarly, a woman with nocturia has 1.32 times the risk of dying earlier as a woman who does not need to get up to urinate during the night.

The study also showed that the more often one got up to urinate, the higher the risk of death.

For instance, among men in the 20 to 49 age group, those who urinated once at night had a 1.4 times higher risk of mortality. This grew to 2.55 times for men who made two night toilet visits and 3.94 times for those who made three and more visits.

The researchers of the New England Research Institutes in the United States calculated these increased risks after taking into account the effects of age, body mass index, marital status, education, smoking, cardiovascular disease, diabetes, hypertension and use of medication.

But the study did not account for other possible confounding factors, such as overactive bladder syndrome, obstructive sleep apnoea (interrupted night-time breathing), benign prostatic hyperplasia (prostate enlargement) and drinking habits before bedtime.

The findings were published in The Journal Of Urology, the official journal of the American Urological Association, in February 2011.

It examined the health records of nearly 16,000 men and women aged 20 and older.

Data from more than 2,000 people in Singapore aged 20 and above, published in the urology journal, BJU International, in 2006, found that 16 per cent woke up twice or more times at night and 5 per cent woke up three or more times.

Dr Teo Jin Kiat, a registrar at the department of urology at Changi General Hospital, said a large overseas study has also shown that less than 5 per cent of people aged 39 and younger have nocturia.

This rises to between 15 and 20 per cent for those aged 50 to 79, and to more than one in five of those aged 80 and above.

It is expected that elderly people wake up more often to urinate at night because of reduced bladder capacity.

With an ageing population, more people are suffering from chronic diseases, such as diabetes, which can cause nocturia.

Dr Gerald Tan, a consultant urologist at Mount Elizabeth Novena Hospital, said he sees double the number of patients with nocturia now than 10 years ago. Six out of every 10 patients he sees with urinary problems will also have nocturia.

Professor Kesavan Esuvaranathan, head of the department of urology at the National University Hospital (NUH), said he sees at least 20 patients with lower urinary tract symptoms, including nocturia, in a week.

This has prompted the setting up of a dedicated nocturia clinic. It will open in September as an extension of the urology service at NUH.

The weekly clinic will see patients whose main complaint is nocturia.

Nocturia a sign of other ailments

Nocturia a sign of other ailments

What is clear to doctors here is that nocturia on its own does not cause death.

Instead, the underlying illnesses that give rise to nocturia are what can kill. For example, obstructive sleep apnoea can raise the risk of death.

In patients with the condition, the airway becomes blocked during sleep, causing frequent pauses in breathing which wake them up.

Dr Kenny Pang, an ear, nose and throat surgeon at Asia Sleep Centre at Paragon, said waking up frequently at night leads to poor quality fragmented sleep.

Poor sleep, in turn, causes a rise in the stress hormone, cortisol, which leads to lower immunity and makes a person more susceptible to infections, he added.

Reduced quality and quantity of sleep has been linked to daytime fatigue, decreased concentration, poorer work performance and accidents.

Obstructive sleep apnoea also increases the risk of high blood pressure and, hence, the risk of heart attack and strokes.

Dr Ng Lay Guat, head and senior consultant at the department of urology at the Singapore General Hospital, warned that it may be more worrying for young people to experience nocturia as it could signal the earlier onset of diseases.

Prof Kesavan said nocturia can even signal to doctors the severity of a patient's illness. For instance, the worse a person's heart function, the greater the pooling of fluids in the lower limbs during the day and, as a result, he has a higher frequency of night-time urination.

Dr Lim Kok Bin, a specialist in urology and consultant at Raffles Urology Centre at Raffles Hospital, agreed that nocturia could be a marker for either poorly controlled chronic illnesses or a harbinger of chronic illnesses.

In addition, the frail, elderly person who wakes up at night to urinate is also at increased risk of falls and fractures, which, in turn, increases his risk of infections and death.

Dr Roy Ng, the head and senior consultant at the division of urogynaecology and pelvic reconstructive surgery at NUH, said women with osteoporosis (brittle bone disease) have a tendency to fracture the neck of the thigh bone, which then causes them to be bed-bound and prone to chest infections, which are sometimes fatal.

Associate Professor Chia Sing Joo, a senior consultant at the department of urology at Tan Tock Seng Hospital, added that standing up upon waking to visit the toilet can lead to a sudden drop in blood pressure - a condition called postural hypotension that is more common in older people - which puts people at increased risk of stroke.

Finding out the root causes

Finding out the root causes

With greater awareness that nocturia can arise from non-urological problems, doctors are now taking more care in establishing the cause of frequent night-time urination and treating any underlying diseases.

Prof Kesavan said in the past, some doctors often ascribed nocturia to benign prostatic hyperplasia in men and stopped short of reviewing the cardiac treatment for such patients.

These days, however, doctors realise that even if an enlarged prostate is treated, a patient's nocturia may not improve as much as other lower urinary tract symptoms due to other existing conditions, such as heart disease.

The cause of nocturia can usually be determined by a detailed medical history, doing a physical examination and reviewing the patient's medication.

Getting the patient to keep a voiding diary - which records the time, volume and type of fluid intake and urine output - also helps.

Tests to assess urinary flow rate and residual volume may be ordered.

Dr Roy Ng said that it is easiest to correct lifestyle factors, such as the drinking of caffeinated beverages near bedtime. Once that is done, other medical conditions will then be investigated.

In their study, the researchers of the New England Research Institutes concluded that nocturia "may present a window of opportunity for intervention in men and women who otherwise may not be considered at increased risk" of death.

But it has not been proven that intervening in night-time urination will reduce morbidity or subsequent mortality risk, they added.

Clearing the way for a better night's sleep

Clearing the way for a better night's sleep

Bible teacher Francis Wan, 62, was diagnosed with obstructive sleep apnoea five years ago. Since then, he has been using a continuous positive airway pressure mask to help blow air into his nose and keep his airway open when he sleeps.

When the strap fastening the mask to his face loosened in recent years, it roused him from sleep three times a night. The act of gasping for air also exerted pressure on his bladder and made him feel the urge to go to the bathroom when he woke up.

This disrupted his sleep and made him so sleepy during the day that the father of two grown-up children had three accidents while driving.

Last month, he underwent surgery to remove the breathing obstructions.

Dr Pang corrected his deviated nasal septum and reduced his sinus turbinates (glandular structures on the inner walls of the nose) and tongue base. The doctor also removed his tonsils (glands at the side and back of the throat) and expanded the back of his throat.

Mr Wan no longer uses the mask and his other conditions are under control. These include his sensitive sinuses, asthma and gastro-oesophageal reflux disease.

Previously, the act of sucking in air deeply into the throat caused stomach acid to flow into his food pipe.

Mr Wan said he now wakes up once each night, if at all, to urinate.

"I feel more refreshed in the morning. The best part for my family is that I no longer snore," he added.

Nocturia can often be resolved by following these lifestyle tips:

Nocturia can often be resolved by following these lifestyle tips:

1. Reduce your fluid intake approximately four hours before you sleep. In fact, try not to drink two hours before bedtime, unless you are very thirsty.

2. Eat your dinner more than two hours before bedtime, so that you can pass out any fluid before you sleep.

3. When consuming medication after dinner, do not drink too much water.

4. Avoid alcoholic and caffeinated beverages in the evening. These make you urinate more often.

5. Refrain from keeping a container of water beside your bed.

6. If you want to hydrate your throat when you wake up in the middle of the night, have a sip of water rather than drink an entire glass.

7. Keep yourself warm by using a blanket or wear socks when you sleep as a cold environment is a stimulant for urination.

Source: Professor Kesavan Esuvaranathan, head of the department of urology at the National University Hospital

joanchew@sph.com.sg


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