Bidirectional Relationship between Pain and Sleep

Understanding Pain | Common Sleep Problems in Chronic Pain | How Pain Affects Sleep How Sleep Affects Pain | The 3-way Bridge of Sleep, Pain, & Mental Health

Overview

Everyone has experienced pain at some time in their life. However, individuals who experience chronic pain know better than most how challenging it is to achieve a restful night’s sleep when pain is always there.

Experts believe that the link between sleep and pain is bidirectional, implies that changes in one can significantly impact the other.

This article will focus on this crucial relationship and provide tips to improve sleep for persons with painful conditions.

Understanding Pain

Although pain is an abstract concept and could mean different things to different people, most experts describe it as an unpleasant sensory or mental experience that results from actual or potential tissue damage.^[1] Typically, pain can be categorized in terms of duration as acute or chronic.

Acute pain describes pain that occurs suddenly and is short-lived. Typically, it is present for some hours to a few weeks, not more.^[2] It’s a pain you feel following banging your foot or hitting the car door on your hand. In all these, the injury heals, and the pain goes away.

In contrast, chronic pain refers to pain that lasts for an extended period, even when there is no (new) damage to the bodily part.^[2] It could last months or years without diminution or resolution.^[2] Common examples include back pain, migraine headaches, cancer pain, and pain caused by nerve injury (neuropathic pain).

Common Sleep Problems in Chronic Pain

More often than not, people who suffer chronic pain experience many sleep problems in addition to the discomfort they feel.

Studies show that insomnia is one of the most frequently reported sleep disturbances among persons with chronic pain.^[3] In Corroboration, emerging evidence indicates that insomnia is more common in those with chronic pain than in the general population.^[4]

Furthermore, people living with chronic pain can experience sleep abnormalities like obstructive sleep apnea (OSA) and restless legs syndrome.^[5]

In some cases, these sleep troubles may be present before the onset of the pain and may have no direct connection to the pain.

How Pain Affects Sleep

Here are some of the ways experts believe pain impacts one’s sleep.

1) Insomnia: People with chronic pain often experience more severe and frequent insomnia. Pain typically causes frequent nocturnal awakenings and shortens sleep duration.^[3] This disorder is the most prevalent sleep complaint among individuals with chronic pain.

These symptoms can be attributed to the need to constantly adjust their sleeping position to alleviate pain. For instance, someone with ankylosing spondylitis may find sleeping on their side or belly uncomfortable. As a result, they may adopt awkward positions or frequently change their position in bed to attain a more comfortable and pain-relieving posture, consciously or unconsciously.

2) Overall Poor Sleep: People experiencing chronic pain face regular disruptions in their sleep, which interfere with the natural progression of sleep stages, including slow-wave sleep and rapid eye movement (REM) sleep. Failing to go through these essential phases properly leads to a lack of feeling rested. It can result in exhaustion upon waking the next day.

3) Side Effects of Medications: The side effects of pain drugs can substantially impact sleep patterns.^[3] Many pain medications, such as opioids, muscle relaxants, and certain nonsteroidal anti-inflammatory drugs (NSAIDs), can cause drowsiness or sedation, which may initially help with falling asleep. However, they can also disrupt the natural sleep architecture by suppressing rapid eye movement (REM) sleep and altering deep sleep stages. Some pain medications can also cause vivid dreams, nightmares, or even sleep disturbances like insomnia.

How Sleep Affects Pain

Although there is an irrefutable bi-directional link between sleep and pain, some experts believe that the influence of sleep on pain may be more potent than the effect of pain on sleep. Some ways sleep affects pain include:

1) Hyperalgesia: In individuals with chronic pain and poor sleep, there is an increased sensitivity to pain. They experience heightened pain responses to the cause of their chronic pain and other everyday stimuli. This is due to the reduced functioning of the opioid nociceptive system, a system of biochemicals and receptors (places they act on) in the brain that typically help regulate and decrease pain perception.^[6] Sleep deprivation contributes to this reduced functioning, leading to an amplified experience of pain.

2) Worsening Inflammation: One of the core symptoms of inflammation is pain. Studies have shown that sleep deprivation causes systemic inflammation and weakens the immune system.^[7] Furthermore, emerging evidence has suggested that melatonin- a hormone critical to initiating sleep- may affect pain perception.^[8]

3) Higher Stress Levels: Anyone with chronic pain is under considerable stress. When such persons cannot get adequate sleep, they become more stressed, and their body releases more stress hormones which worsens inflammation, consequently causing an increased perception of pain.

The 3-way Bridge of Sleep, Pain, & Mental Health

Studies show that mental health problems such as anxiety or depression tend to occur in people with pain-related sleep disturbances.^[9]

Patients with painful health conditions typically experience a self-perpetuating vicious cycle of pain, sleeplessness, despair, or anxiety. For instance, a person in discomfort who cannot sleep may develop anxiety.

They may sleep inadequately and awaken depressed, which heightens their pain sensitivity. This cycle may persist for several days or weeks, exacerbating the pre-existing health condition and worsening the quality of life.

Strategies for Sound Sleep for Those with Chronic Pain

Falling asleep in chronic pain can be extremely difficult, so you must learn strategies and techniques to help achieve this, including changes in the psychology of the situation and behavior.

1) Mindfulness and Relaxation Exercises: One of the ways pain prevents sleep is by keeping the brain active. Mindfulness exercises such as breath control can help reinstate a calm mind and body. Typically, these exercises help redirect attention away from the pain, reducing brain arousal and contributing to a more peaceful and restful night’s sleep.

2) Stimulant Avoidance: When going to bed or close to bedtime, avoid taking caffeinated drinks and alcohol. Avoidance of stimulants is inimical to the goal of initiating sleep. Also, other stimulants for the brain, like screens, should be avoided or put off close to bed, which includes phones, laptops, televisions, etc.

3) Use the Bedroom Only for Sleep Activities.: Maintaining a clear distinction between the bedroom and daily concerns is vital to optimizing sleep. It’s advisable to reserve the bedroom solely for rest and sleep-related activities. If you cannot sleep and thoughts about the day’s events occupy your mind, leave the bedroom. Return to bed only when you feel sleepy again. Doing this allows your brain to associate the bedroom exclusively with sleep.

4) Keep a Bedtime Routine: Set up a sequence of activities you follow (like a ritual) just before bed. This process might extend over a few minutes to 30 minutes. Importantly, you want to keep these regular and do them daily before bed. The frequency of these activities allows your body to recognize it’s time for sleep as soon as you begin them and hence start ‘winding down’ as you prepare to sleep.

5) See Your Doctor: Suppose there is still no significant improvement in your sleep. In that case, it might be imperative to see your doctor or mental health professional who can help with medications and other expert techniques to help you manage pain and sleep.

References:

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