Insomnia can double the risk of prostate cancer in men, a study has shown.
The risk rises proportionately with the severity of sleep problems, researchers found, increasing from 1.6 to 2.1 times the usual level.
Why poor sleep can affect men's chances of developing the disease is unexplained. But a previous link has been seen between insomnia and breast cancer in women.
"Sleep problems are very common in modern society and can have adverse health consequences," said study leader Dr Lara Sigurdardottir, from the University of Iceland in Reykjavik.
"Women with sleep disruption have consistently been reported to be at an increased risk for breast cancer, but less is known about the potential role of sleep problems in prostate cancer."
Each year around 40,000 men in the UK are diagnosed with prostate cancer and 10,000 die from the disease.
The researchers studied more than 2,000 men aged 67 to 96 who were questioned about their sleeping habits. Specifically, they were asked if they took sleeping pills, had trouble falling asleep, found it difficult to get back to sleep after waking in the night, or woke early and stayed awake.
Among the participants, between 8.7% and 5.7% reported severe and very severe sleep problems. None had prostate cancer at the start of the study, which continued for five years.
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A lump or swelling anywhere on your body needs checking out
AXA’s research found that 79% of people were able to correctly identify breast lumps as a potential indicator of cancer. But a lump or swelling in any part of the body, including the armpit, neck, abdomen, groin or chest area, is worth having checked by a doctor.
Talk about your toilet habits
Diarrhoea or changes in bowel habits are most likely to be caused by a stomach bug or eating something that disagrees with you. But if you’re noticing changes that have lasted more than a few days, for example if your bowel movements are looser for three weeks or more, or you notice any blood when you’ve been to the toilet, then make an appointment to get it checked out.
Sores and ulcers should disappear quickly – investigate them if they don’t
A lot of people get mouth ulcers when their immune system is low or they’re stressed. Generally they’re nothing to worry about and, as the lining of the mouth regenerates itself every couple of weeks, shouldn’t last long. But any ulcer that hasn’t healed after three weeks merits attention from your doctor or dentist. The same goes for any sore or spot that lasts for several weeks without healing – get it checked by a doctor.
Difficult passing urine – not just an inevitable consequence of age
Many men find it more difficult to pass urine as they get older, needing to go more often or urgently or being unable to go when they need to. These problems are usually caused by an enlarged prostate, which is a common condition that is not in itself cause for concern. But occasionally these symptoms can be a sign of prostate cancer – either way, men experiencing these symptoms should see their GP. Similarly, while urinary tract infections are the most likely cause of women having pain or difficulty passing urine, this should pass relatively quickly. If it doesn’t, then any sudden urges to pass urine or the need to go more often should be discussed with your doctor.
Lost weight without dieting?
It’s natural for most people’s weight to fluctuate over time. But if you haven’t instigated any changes in your diet or exercise regime and have obviously lost weight, then talk to your doctor. And if you’re experiencing heavy night sweats you should seek medical advice – these don’t always have a sinister cause, and can be brought about by certain infections or medications, but they’re worth checking.
Coughing up blood needs to be checked out
If you’ve coughed up any blood, you should see your doctor, regardless of the amount of blood or frequency. It can be a sign of lung cancer, so needs to be checked out.
Coughs and sore throats
Most of us will experience coughs or croaky voices at some point, normally when we’ve had a cold. But as with many other changes to your body, anything that hasn’t gone away after three weeks or so should be investigated.
Educate yourself on what to look out for
AXA’s research found women were more likely than men to identify key cancer warning signs, including breast lumps, changes in bowel habits and irregular moles. But for both men and women, ensuring you’re aware of symptoms to keep an eye out for is important. Knowledge is power: understanding what you’re looking for means you can any changes checked out quickly.
Know your own body
AXA’s research found only 6% of men and 3% of women check their bodies daily for anything unusual. But understanding what’s normal for your own body is essential if you’re to spot when anything has changed. If you do notice changes that are persisting for a long time, or causing you pain and discomfort, then see your GP.
Don’t put off seeing the doctor!
A sizeable 61% of people AXA spoke to admitted they’d delayed seeing their doctor when they spotted changes that could be potential flags for cancer. But early detection of any problems can make a huge difference if any treatment is then needed. Similarly, if changes are harmless your doctor will be able to reassure you. Overall, the sooner you go to see your GP, the better.
During this time, 6.4% of the men were diagnosed with prostate cancer. Compared with men who had no problems sleeping, those suffering from insomnia were significantly more likely to develop prostate cancer.
The association was stronger for advanced stage disease. For men with "very severe" sleep problems, the risk of being diagnosed with advanced prostate cancer was more than tripled.
The researchers took steps to rule out the possibility that sleep problems were caused by undiagnosed prostate cancer or enlarged prostate glands, which can cause an urge to urinate during the night.
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Build time into your day for a bedtime routine-we are more like dimmer switches than ‘on-off switches’ so we need time to unwind. This may include a warm bath, a hot milky drink/chamomile tea and listening to some relaxing music or an audio book.
Pull your socks up
Wear socks to bed. Cold feet = a poor night's sleep. Due to the fact that they have the poorest circulation, the feet often feel cold before the rest of the body and studies have shown that wearing socks reduces night awakenings.
Use sunlight to set your body clock
As soon as you get up in the morning, go outside and get some fresh air for 10 minutes. The bright sunlight (or any bright light) tells your body’s natural biological clock that it’s time to wake up and that same clock will then be set to tell your body it’s time to go to sleep about 14-16 hours later.
Don't change your bedtime. You should go to bed and wake up at about the same time each day, even on the weekends! This will help your body to get into a sleep rhythm and make it easier to fall asleep and get up in the morning.
Change your bedding once a week and dust regularly. Fresh crisp sheets will help you get a better night’s sleep and clearing excess dust can help minimise any irritation in the airways, which could disrupt sleep. Review your bed linen for a better night’s sleep and choose sheets that feel comfortable against your skin. Research carried out by Lenor has shown that 74% of people surveyed slept drastically better on freshly washed bed sheets.
If you're too warm it can lead to a fitful night's sleep. Your body works hard to regulate your temperature while you're asleep, so help it along with cool, breathable cottons and keep the room cool at 16-18 degrees centigrade. If you share your bed and like different temperatures consider buying two separate duvets.
Exercise to sleep
Regular exercisers have better quality sleep. Aerobic exercise in particular has a significant impact on sleep particularly when it’s done in daylight so try to integrate exercise into your life by moving throughout the day eg getting off the bus one stop early, taking a walk in your lunch break etc.
Set yourself a technology cut off time
Computers, mobiles, smart phones and TVs all over stimulate our minds and ruin sleep, so try to turn them off at around 9pm. Where possible keep them out of the bedroom.
Room and bed sheet fragrance
Fragrances can set the tone of the room and generate a calming effect which will induce better quality deep sleep leaving you more rested, energetic and alert the next morning. Filling the bedroom with lavender or chamomile scents around an hour before bedtime will create the proper atmosphere for relaxation, sleep or romance. Try washing your sheets in fragrant Lenor fabric softener or alternatively place a few drops of relaxing aromatherapy oils on your pillow.
Sleep in complete darkness or as close to that as you can. There also should be as little light in the bathroom as possible if you get up in the middle of the night. As soon as you turn on the light, your body will immediately cease all production of the important sleep aid melatonin which regulates the sleep-wake cycle.
The findings are published in the American Association for Cancer Research journal Cancer Epidemiology, Biomarkers & Prevention.
Dr Sigurdardottir added: "Prostate cancer is one of the leading public health concerns for men, and sleep problems are quite common. If our results are confirmed with further studies, sleep may become a potential target for intervention to reduce the risk of prostate cancer."
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