Sleep Disturbances and Osteoarthritis

By Leesha Lentz

New research examines how sleep disturbances affect patients with osteoarthritis pain.

In the study "Sleep Disturbance in Osteoarthritis: Linkages With Pain, Disability and Depressive Symptoms," published in Arthritis Care and Research, coauthor Patricia Parmelee, PhD, director of the Center for Mental Health & Aging at the University of Alabama (UA), investigated the complex relationships among osteoarthritis pain, disability, depression, and sleep disturbances—one of the few studies to examine the association between all four variables. While osteoarthritis pain and depression have been linked in previous studies, there has been limited research on sleep disturbances and osteoarthritis' impact on physical functioning.

For the study, 367 patients diagnosed with knee osteoarthritis were asked to report on sleep disturbances, functional well-being, depression, and osteoarthritis-related pain. The same measures were repeated with 288 of the 367 patients one year later at follow-up.
According to the UA press release, the original scope of the study "was to measure how osteoarthritis affected the fun things participants liked to do, like exercising or gardening," but after her interests began to evolve, Parmelee decided to take a closer look at sleep's role in osteoarthritis and depression.

"I had not done any work on sleep until a few years ago, and I began to get interested in it because quite honestly, so much of research is autobiographical. I have family members that have osteoarthritis, and they have one by one begun to complain that it wakes them up at night. I began to get interested in how pain affects sleep," she says.

After speaking with Natalie D. Dautovich, PhD, a study coauthor and a clinical geropsychology professor at UA who studies late-life sleep, Parmelee was able to pull information from the data they collected, even though sleep wasn't originally the focus of the research. Through the study, they conducted a diagnostic depression checklist, which included sleep disturbances as a symptom of depression. After removing that open-ended question about the quality of their sleep from the semistructured interviews with study participants, Parmelee and her colleagues coded the item from no sleep disturbance to severe and clinically relevant sleep disturbance. "We were using a very gross measure of sleep disturbance in this study and yet, as it turns out, there are very strong associations with pain, disability, and depression," she says.

Parmelee evaluated these data and was shocked by two findings in particular. First, she noticed that sleep interacted with pain to exacerbate depression among patients with high levels of osteoarthritis pain. "People who have both sleep disturbances and severe pain are at a very high risk of depression, much more so than people who may have equivalent pain but aren't having trouble sleeping," she says. "I thought that was really quite important because it tells us that we really need to pay attention to these kinds of problems. So much of the literature these days is about sleep, but when you get both a painful condition and a sleep disturbance, you're at very high risk of depression and that's something that we can easily intervene to prevent."

Second, Parmelee discovered that analyses of sleep disturbances at baseline predicted functional decline over the one-year period, independent of other factors. "So people who were having sleep disturbances were actually more likely to have functional decline over one year's time than those who were not having sleep problems, but were having the same problems with pain. That's a real shocker to me," she says. "It suggests that it's not just quality of life in terms of their emotional well-being but that sleep really can affect your functional ability and your ability to get around and do what you want to do. This makes it very important to assess and identify problems so we can treat them appropriately."

What Physicians Should Know
While follow-up research is required to determine exactly how osteoarthritis interacts with the body to cause sleep disturbances and depression, the link between them does caution physicians to assess for possible sleep problems and osteoarthritis pain during consultations with older adult patients. "What this study is telling us is that we do need to pay attention because [osteoarthritis] affects other aspects of functioning and other syndromes that can have a profound effect on both physical and emotional well-being," Parmelee says.

However, Parmelee recognizes that it can be difficult to assess for joint pain and sleep problems, because the average older adult presents with several chronic problems, so the former may get lost in the mix. Additionally, there are limited intervention options for physicians. She or he can prescribe physical therapy to help the joints stay strong, but osteoarthritis is not something that can be completely fixed. "Osteoarthritis is so common. It's a disease of life; if you use your joints enough, you're likely to have some wear and tear," Parmelee says.

Assessing for sleep problems may also be complicated because sleep patterns can change. An 80-year-old is less likely to get seven to eight hours straight of sleep compared with a 30-year-old, according to Parmelee. Physicians may be able to intervene and aid those problems by adjusting medications if pain is causing the sleep disturbance, although Parmelee notes that there are many nonpharmalogical options to reduce pain and improve sleep. "This should be the first line of attack," she says.

And it may start with evaluating the basics of patients' sleep hygiene. "There are so many bad habits that interfere with our sleep. We talk about how busy America is and how we're all just too busy to sleep. Very often it's just that we have very terrible sleep hygiene," Parmelee says.

She offers the following principles of good sleep hygiene that physicians can relay to their patients:

• Get some exercise during the day. "It's the best thing in the world to aid sleep and reduce depression, the getting out and about as much as one can," Parmelee says.

• Avoid caffeinated beverages and alcohol in the evenings.

• Don't use the computer before bed. "We know that sitting in front of a computer screen will wake you right up and keep you up at night," Parmelee says.

• If the pain is bothersome at night, use a heating pad.

The National Sleep Foundation also offers the following tips for basic sleep hygiene:

• Avoid from large meals close to bedtime.

• Get adequate exposure to natural light. "This is particularly important for older people who may not venture outside as frequently as children and adults. Light exposure helps maintain a healthy sleep-wake cycle," according to its website.

• Establish a regular bedtime routine.

• Try to maintain a regular sleep-wake schedule throughout the week.

"So just good sleep hygiene is the first step, and after that we can start looking at how sleep and pain and mood are interacting and start devising some more complicated individually oriented intervention," Parmelee says. "If they're really having trouble, a good psychologist could be very helpful in developing both good sleep habits, such as the cognitive strategies that one needs to deal with pain and with sleep disturbances."

For more information on sleep hygiene and what patients can do to improve sleep health, visit the National Sleep Foundation's website at www.sleepfoundation.org.

— Leesha Lentz is an editorial assistant at Today's Geriatric Medicine.