Poor sleep quality is associated with increased disability among people with rheumatoid arthritis, or RA, according to a study in the February 15, 2011,  Journal of Clinical Sleep Medicine.

"Helping [RA] patients to get a solid night's sleep could have a huge impact on their health and quality of life," says lead study author Faith S. Luyster, PhD, a research assistant in the department of psychiatry at the University of Pittsburgh School of Nursing.

Disturbed sleep is common among people with RA, and previously has been linked to higher levels of depression, pain and fatigue in these patients. Less is known, however, about the association between poor sleep and functional disability in RA patients.

So Luyster and colleagues looked directly at the relationship between sleep quality and disability in 162 patients who had had RA for at least two years and an average of 14 years. Their average age was 59, and 76 percent were female.

Participants filled out questionnaires that covered nearly two dozen measures of sleep quality, such as whether they had trouble falling or staying asleep. Additionally, they provided information concerning depression, fatigue, pain severity and functional disability – whether they had trouble tying their shoes or buttoning their shirts, for example.

Results showed 61 percent of participants were poor sleepers, according to the sleep questionnaire. A total of 33 percent reported pain severe enough to disrupt their sleep at least three times per week.

After adjusting for age, gender, other illnesses, duration of RA and treatment, poor sleep quality was significantly related to greater functional disability, Luyster says.

When the analysis was further adjusted for patients' pain severity and fatigue symptoms, however, there was no longer a link between sleep quality and disability. "This suggests sleep quality has an indirect effect on functional disability through its relationship with pain severity and fatigue," she explains.

A still unanswered question is which comes first: worse disability or poor sleep, says Stanley B. Cohen, MD, a practicing rheumatologist and clinical professor of internal medicine at the University of Texas Southwestern Medical School in Dallas.

"It could be that people with worse pain and disability can't sleep well. Or not sleeping well may contribute to pain and fatigue during the day, which can affect one's everyday functioning," he says.

"Either way, it becomes a vicious cycle. There is no question that poor sleep will aggravate the fatigue and discomfort of RA," says Dr. Cohen.

Luyster offers these tips for getting a better night's sleep:
• Set a consistent bedtime and wake time.
• Avoid alcohol and caffeine in the evening.
• Reserve the bed for sleeping and sex only.
• Make your bedroom cool, dark, quiet and comfortable.

If you suffer pain at night, Dr. Cohen suggests you talk to your doctor about your options – from over-the-counter pain relievers to prescription pain relievers and sleep aids.