Whether it’s from a sore lower back or throbbing tooth, pain is hard enough to deal with in the light of day. But pain at night that robs you of your much-needed sleep can be downright exhausting.
“An individual simply cannot get comfortable to fall asleep due to the discomfort of pain,” says Frank. J. Falco, MD, who specializes in pain management and sleep problems in Newark, Del. Plus, pain causes anxiety, which disrupts sleep even more.
In addition to preventing a person from falling asleep, pain also results in difficulty staying asleep. And once pain keeps you awake one night, it is likely to do the same thing again and again. Pain-related insomnia gets worse over time.
If pain keeps you up, take comfort in knowing you are not alone. According to the National Sleep Foundation, two out of three people with chronic pain have trouble sleeping.
Many types of pain can interrupt sleep, from the chronic pain of arthritis to the acute pain that follows surgery.
“But no matter what the cause, it is the intensity and quality of the pain, not necessarily the type, that determines the impact on a person’s quality of life, including sleep,” says Falco, who heads Mid-Atlantic Spine and Pain.
The Relationship Between Pain and Sleep
“Pain is a sensation you feel when nerves are stimulated to an intense degree,” says Tracey Marks, MD, an Atlanta-based psychiatrist. Marks is author of Master Your Sleep: Proven Methods Simplified. “This stimulation activates the brain, which keeps you awake.”
Some of the ways pain causes insomnia include the following:
Pain at night disrupts sleep architecture.
“You need a certain amount of each stage of sleep to feel rested and for proper memory,” Marks says. These stages include light sleep, deep sleep, and REM (rapid eye movement) sleep. “We normally go through four to six cycles of these stages per night. But if pain wakes you up, you spend too much time in light sleep,” she explains. This reduced sleep -- in particular, shortened REM -- may increase sensitivity to pain.
Pain affects sleep position.
Certain types of pain, such as arthritis pain and orthopedic pain, may prevent you from getting comfortable at night, says Reena Mehra, MD, of University Hospitals Case Medical Center in Cleveland. The medical director of adult sleep services says joint and muscle pain usually results in problems staying asleep (called sleep maintenance insomnia) rather than falling asleep (called sleep onset insomnia).
Sleep deprivation makes you more sensitive to pain.
A study in the April 2009 issue of Sleep Journal showed that normal, healthy individuals are more sensitive to pain when they are low on rest. The reasons why aren’t known for sure. “Some research studies show that sleep deprivation causes increased production of inflammatory chemicals in the body called cytokines,” Marks says.
Pain medications interrupt sleep. Unfortunately, some of the medications prescribed for pain, such as codeine and morphine, can cause insomnia. These opioid pain medications can cause apnea, brief pauses in breathing, during sleep. “Therefore, people who take these kinds of medications for chronic pain are at a higher risk for sleep problems,” Falco says.
People with chronic pain may have trouble exercising. Lack of exercise leads to weight gain. Excess weight then restricts exercise, which leads to more pounds gained. “This vicious cycle can lead to sleep apnea, which prevents a restful night’s sleep,” Falco says.