Diseases and Their Relationship With Sleep


Cancer is a general term for over 100 different diseases, and it affects the body in many ways. Pain from the tumor can disrupt sleep and various discomforts from treatment can wreak havoc on a patient’s ability to get to and stay asleep. A Duke University study found that the effect of cancer on sleep is "one of the most persistent and disruptive" challenges a typical cancer patient faces.

The stress of a cancer diagnosis and worrying about what is often a long-term disease and lengthy treatment causes a lot of insomnia.

Oncology nurses speak a lot about “cancer-related fatigue” (CRF), but sleep disturbances are more than just fatigue.  Insufficient sleep can make the patient more irritable and less amenable (both psychologically and physically) to treatments.  Chemotherapy patients experience insomnia at three times the rate of the general population

Fatigue is a side effect of chemotherapy, radiation therapy, and surgery.  The patient feels sleepy during the day and experiences unrefreshing sleep at night.

Breast cancer often shifts the cortisol patterns so the levels of this stress hormone associated with sleep are higher in the afternoon than upon morning awakening.  Also, cancer in the chest (e.g. esophageal or lung cancer) can make apnea worse.

Here’s an interesting PDF on cancer-related fatigue and sleep
disorders: http://theoncologist.alphamedpress.org/content/12/suppl_1/35.full.pdf

Both doctors and patients may be reluctant to use pharmacological treatments for insomnia because the cancer patient is already taking so many drugs.  Opioids - strong pain drugs given to some cancer patients – depress breathing and are not given to people with apnea.

There is also interest among scientists in the connection between the body's circadian cycles and cancer growth.

Circadian rhythms and tumor growth.

Circadian Disruption Accelerates Tumor Growth and Angio/Stromagenesis through a Wnt Signaling Pathway


Multiple Sclerosis

Many multiple sclerosis patients have sleep disorders and although there are no definitive numbers, there are suggestions that ratesC of insomnia, restless legs syndrome, and apnea run higher than in the general population. Sleep disorders in MS patients are often underdiagnosed.

Fatigue is one of the most complained-about symptoms of MS and the more advanced the disease is, the worse the fatigue.  It is not clear how much of the fatigue is due to the disease and how much is due to sleep disturbances.  In any case, recent studies indicate that fatigue plays a minor part in sleep disorders.

It may be that the sleep disorders contribute to the fatigue. REM sleep behavior disorder, and sleep disordered breathing, leg cramps, and insomnia are all prevalent in MS patients. An Italian study found that half of MS patients had restless leg syndrome. A recent survey found multiple sclerosis patients are underdiagnosed in the area of sleep disorders.

Medicines for the MS may interfere with sleep, as well as the pain of the disease.  Because MS is incurable Doctors look at improving sleep quality and duration as a way of improving the quality of life Insomnia is more common in MS patients than in the general population and more common than in people many other chronic diseases.  It also appears to be more common in women with MS than in men.

The bodies of people with MS have trouble with thermal regulation, which is tied to the sleep cycle.  Yawning is also a common symptom of MS.

NIH: Sleep disturbances in multiple sclerosis.


People with hypertension are more apt to suffer from insomnia, although how much more likely they are to have sleep problems is not clear. Estimates range from an insomnia prevalence more than twice the average of people with normal blood pressure to only slightly more prevalent.

A study published in American Heart Association’s journal Hypertension found that quality of sleep was tied to cardiovascular health.  Poor quality sleep is correlated with high blood pressure.  Specifically, a lack of Stage 3 deep sleep and hypertension go together, regardless of the length of sleep time a person gets.  It’s long been known there is a correlation between apnea and high blood pressure, although this could be due to a common cause (obesity).  The correlation between poor quality sleep and high body weight has also been known for a long time.  This Harvard Medical School study is the first direct tie between lack of deep sleep and high blood pressure.

On average, a person’s blood pressure drops 10 points (millimeters of mercury) when he or she goes into deep sleep. Although even though the best adult sleepers spend less than two hours per night in deep sleep, this nightly respite appears to be important to maintaining reasonable waking blood pressure.  An earlier study published in 2003 stated that people who lack the nighttime fall in blood pressure are at greater risk for cardiovascular events.

A similar result was found by the Dept of Veterans Affairs in a study specifically of older men.  The men in the study did not have hypertension at the time the researchers started following them, but they did have poor quality sleep.  A decrease in slow-wave sleep is common in the elderly. These men developed hypertension over the next several years at a high rate, further suggesting a connection between poor sleep and high blood pressure. http://www.ncbi.nlm.nih.gov/pubmed/21876072

A British study of women only found an even stronger correlation between insomnia and hypertension in premenopausal women: Short sleep (low average sleep time per night) has been linked with risk for hypertension.

Women who get high blood pressure during pregnancy also have higher rates of sleep-disordered breathing.  The causes and effects here are not clear. People with the very serious problem of pulmonary hypertension are known to have poor quality sleep; this is an incidence of insomnia being a symptom of another condition.

Cardiobrief: Studies Probe Effect Of CPAP And Sleep Apnea On Hypertension

A recent study has cast doubt on the connection between insomnia and hypertension. This was a large study and looked specifically at the question of a link, but was unable to find one. As near as we can tell, both insomnia and hypertension are very common and in most cases probably have connections to other issues in the body, so even if there is no direct connection, they are both worth considering in any treatment plan.


Fibromyalgia, despite being common, is still somewhat mysterious. Patients have a range on symptoms, including rather bad pain.  This website addresses sleep issues.  When formulating its most recent diagnostic definition of fibromyalgia in 2010, the American College of Rheumatology included excessive daytime sleepiness, fatigue, tiredness, and insomnia.

Polysomnographic tests have found fibromyalgia patients sleep about the normal amount, but with an increase in short-wave shallow sleep at the expense of deep sleep – a  deterioration in sleep quality common to many illnesses.  They also more frequently have periodic leg movements associated with cortical arousals, although if there is a connection with restless legs syndrome is not clear.

Detailed study has found that people with fibromyalgia and chronic fatigue syndrome more often transition from REM sleep to Stage 1 sleep and from Stage 3 or 4 sleep to Stage 1 sleep than healthy people, although the architecture of sleep patterns between the two illnesses are different.

Obesity is common in fibromyalgia patients and also the severity of the obesity correlates with lower sleep quality.


Arthritis sufferers also have sleep disturbances more often that those without arthritis.  Part of this can be traced to the pain of the arthritis. But in addition to pain the symptoms and effects of arthritis come into play also.  The fatigue that people feel, which they describe as different from normal tiredness, makes it difficult to sleep. Depression is often co-morbid with arthritis and makes it difficult to sleep.  Polysomnograms have shown arthritis patients have fragmented sleep.


People with cirrhosis often have sleep disturbances. These appear to be circadian alterations, with the body’s time signals shifted later.  A study found one-third of cirrhosis patients had delayed sleep phase syndrome due to their illness.


Insomnia and other disturbances are common symptoms of tinnitus, or ringing in the ears, the insomnia makes the tinnitus more miserable and may contribute to the development of mental illness. It has been suggested that hyperarousal is a common underpinning in the development of both tinnitus and insomnia.

Common Cold

Cold and flu symptoms get worse at night and make it harder to sleep. Nasal congestion can make you cough and sleeping with the mouth open is uncomfortable. Cytokines released by the immune system to fight the disease can have paradoxical effects on sleep, sometimes enhancing the subjective experience of sleep and increasing sleep time, and sometimes making it difficult to maintain sleep. Cold medicines sometimes contain pseudoephedrine as a decongestant and that drug is chemically similar to amphetamine and acts as a stimulant to some people, although some find it helps them sleep. Antihistamines in cold medicine usually induce drowsiness, but works the opposite for a subset of the population.

Over-the-counter pain relievers can reduce aching and help you sleep, although be sure to check the ingredients of any cold medicine, as some of them already contain an analgesic. Humidifiers help some people by taking care of dry air and providing white noise.

Sleep and its connection to health

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