Patients suffering from chronic pain often find that their problems are compounded by the additional difficulties that come with insomnia and sleeping disorders. Of those who report experiencing chronic pain, approximately 65% report having sleep disorders, such as disrupted or non-restorative sleep.
In a recent study, it was found that approximately two-thirds of patients with chronic back pain suffered from sleep disorders. Research has demonstrated that disrupted sleep will, in turn, exacerbate the chronic back pain problem. Thus, a vicious cycle develops in which the back pain disrupts one’s sleep, and difficulty sleeping makes the pain worse, which in turn makes sleeping more difficult, etc.
Why it Occurs
Common causes of insomnia include:
• Stress. Concerns about work, school, health or family can keep your mind active at night, making it difficult to sleep. Stressful life events, such as the death or illness of a loved one, divorce or a job loss, may lead to insomnia.
• Anxiety. Everyday anxieties as well as more-serious anxiety disorders may disrupt your asleep.
• Depression. You might either sleep too much or have trouble sleeping if you’re depressed. This may be due to chemical imbalances in your brain or because worries that accompany depression may keep you from relaxing enough to fall asleep. Insomnia often accompanies other mental health disorders as well.
• Medications. Many prescription drugs can interfere with sleep, including some antidepressants, heart and blood pressure medications, allergy medications, stimulants (such as Ritalin) and corticosteroids. Many over-the-counter (OTC) medications, including some pain medication combinations, decongestants and weight-loss products, contain caffeine and other stimulants. Antihistamines may initially make you groggy, but they can worsen urinary problems, causing you to get up to urinate more during the night.
• Caffeine, nicotine and alcohol. Coffee, tea, cola and other caffeine-containing drinks are well-known stimulants. Drinking coffee in the late afternoon and later can keep you from falling asleep at night. Nicotine in tobacco products is another stimulant that can cause insomnia. Alcohol is a sedative that may help you fall asleep, but it prevents deeper stages of sleep and often causes you to awaken in the middle of the night.
• Medical conditions. If you have chronic pain, breathing difficulties or a need to urinate frequently, you might develop insomnia. Conditions linked with insomnia include arthritis, cancer, heart failure, lung disease, gastroesophageal reflux disease (GERD), overactive thyroid, stroke, Parkinson disease and Alzheimer’s disease. Making sure that your medical conditions are well treated may help with your insomnia. If you have arthritis, for example, taking a pain reliever before bed may help you sleep better.
• Change in your environment or work schedule. Travel or working a late or early shift can disrupt your body’s circadian rhythms, making it difficult to sleep. Your circadian rhythms act as internal clocks, guiding such things as your sleep-wake cycle, metabolism and body temperature.
• Poor sleep habits. Habits that help promote good sleep are called sleep hygiene. Poor sleep hygiene includes an irregular sleep schedule, stimulating activities before bed, an uncomfortable sleep environment and use of your bed for activities other than sleep or sex.
• ‘Learned’ insomnia. This may occur when you worry excessively about not being able to sleep well and try too hard to fall asleep. Most people with this condition sleep better when they’re away from their usual sleep environment or when they don’t try to sleep, such as when they’re watching TV or reading.
• Eating too much late in the evening. Having a light snack before bedtime is OK, but eating too much may cause you to feel physically uncomfortable while lying down, making it difficult to get to sleep. Many people also experience heartburn, a backflow of acid and food from the stomach into the esophagus after eating. This uncomfortable feeling may keep you awake
Insomnia and aging
Insomnia becomes more common with age. As you get older, changes can occur that may affect your sleep. You may experience:
• A change in sleep patterns. Sleep often becomes less restful as you age, and you may find that noise or other changes in your environment are more likely to wake you as you get older. With age, your internal clock often advances, which means you get tired earlier in the evening and wake up earlier in the morning. But older people generally still need the same amount of sleep as younger people do.
• A change in activity. You may be less physically or socially active. Activity helps promote a good night’s sleep. You may also be more likely to take a daily nap, which also can interfere with sleep at night.
• A change in health. The chronic pain of conditions such as arthritis or back problems as well as depression, anxiety and stress can interfere with sleep. Older men often develop noncancerous enlargement of the prostate gland (benign prostatic hyperplasia), which can cause the need to urinate frequently, interrupting sleep. In women, hot flashes that accompany menopause can be equally disruptive.
Other sleep-related disorders, such as sleep apnea and restless legs syndrome, also become more common with age. Sleep apnea causes you to stop breathing periodically throughout the night. Restless legs syndrome causes unpleasant sensations in your legs and an almost irresistible desire to move them, which may prevent you from falling asleep.
• Increased use of medications. Older people use more prescription drugs than younger people do, which increases the chance of insomnia caused by a medication.
The moderately positive relationship between pain severity and sleep complaints, and the specificity of pain-related arousal and mediating variables such as depression, illustrate that insomnia in relation to chronic pain is multifaceted and poorly understood. This may explain the limited success of the available treatments. Non-pharmacological interventions should not be considered as single interventions, but in association with one another.
Some non-pharmacological interventions especially the cognitive and behavioral approaches, can be easily implemented in general practice (e.g. stimulus control, sleep restriction, imagery training and progressive muscle relaxation).
Hypnotics are routinely prescribed in the medically ill, regardless of their adverse effects; however, their long-term efficacy is not supported by robust evidence. Antidepressants provide an interesting alternative to hypnotics, since they can improve pain perception as well as sleep disorders in selected patients. Sedative antipsychotics can be considered for sleep disturbances in those patients exhibiting psychotic features, or for those with contraindications to benzodiazepines. Low doses of sedative antipsychotics may improve chronic insomnia in the elderly. However, no intervention is likely to be effective unless a good physician-patient relationship is developed.
1. CNS Drugs. 2004;18(5):285-96. Management of insomnia in patients with chronic pain conditions.
Stiefel F, Stagno D; Psychiatry Service, University Hospital Lausanne, 1011 Lausanne, Switzerland. Frederic.Stiefel@inst.hospvd.ch