Sleep Disturbance, Central Pain Modulation, and Clinical Pain in Osteoarthritis (The SOAP Study)

Sleep disturbance and pain are two of the most common and disabling symptoms of OA. Sleep disturbances have been shown to worsen clinical pain by impairing some of the body's central pain processing mechanisms. Sufficient research is lacking, however, on what treatments may be effective for sleep disturbance in people with OA or whether normalization of sleep patterns in people with OA will reduce their pain. This study will evaluate the effectiveness of behavioral treatments for insomnia in reducing sleep disturbances, thereby reducing clinical pain in people with knee OA.

Participants in Phase 1 of this study will be separated into the following four groups: people with OA and insomnia; people with OA, but without insomnia; people without OA, but with insomnia; and people without OA or insomnia. All participants will attend two study visits. During Visit 1, participants will complete questionnaires and an interview and will provide a urine sample and a set of recent x-rays. A diary, which will be used to record activity levels for 2 weeks, will also be given to all participants.

Optional Ancillary Sleep and Immunoreactivity Study Procedures

Subjects who pass the visit one screen will be provided the option of participating in ancillary study procedures designed to assess inflammatory biomarkers present in plasma, physical functioning capabilities, and pain and mood status during the pain testing procedures. Subjects will be asked to give blood samples during the pain testing procedures, followed by standardized tests of physical function. Subjects will be also asked to complete additional questionnaire and diary items that ask them to rate their emotions during the pain testing procedures and during the days that they keep their electronic diary for the parent project. At Visit 2, participants will undergo pain testing, an in-home sleep study and optional procedures outlined above. At Visit 3, participants with knee osteoarthritis will have an exam by a rheumatologist.

Participants in Phase 1 who have both knee OA and insomnia will be asked to continue into Phase 2, which will last 8 months. These participants will be randomly assigned to receive two different forms of behavioral treatment, cognitive behavior therapy (CBT) or a behavioral desensitization treatment. Participants assigned to both treatments will meet with a psychologist once a week for 8 weeks. Participants will learn new sleeping habits and mental exercises designed to reduce arousal and alertness while trying to sleep. All participants will attend four assessment visits over the course of Phase 2. The first visit will occur at Week 4 and will include completing questionnaires and undergoing pain testing. The second visit will occur at Week 8 and will include the same questionnaires, further pain testing with optional blood draws and physical tests and an in-home sleep study. Two weeks before assessment Visit 3, participants will receive a diary in the mail, which they will use to keep track of their pain, sleep, medications, and symptoms until Visit 3. Assessment Visit 3 will take place at Month 5 and will include the same procedures followed during Visit 2. Participants will complete a second diary 2 weeks before Visit 4. At Visit 4, which will occur at Month 8, the same procedures completed at Visits 2 and 3 will be repeated.