Sleep, Pain and Inflammatory Processes in Older Adults With Osteoarthritis

Inclusion Criteria: * 50-75 years of age (for women, post-menopausal) * Kellgren-Lawrence grade II radiographic evidence of OA affecting one or both knees * knee pain on most days for ≥ 6 months * self-reported disability due to knee pain for ≥ 2 of the following: walking, kneeling, ascending or descending stairs, or performing daily activities * willing and able to avoid all prescription and non-prescription, non-opiate pain medication for 48 hours prior to testing and all narcotic pain medication for 2 weeks prior to testing * meets research diagnostic criteria for sleep maintenance insomnia Exclusion Criteria: * health conditions with immunological components or undergoing or taking immunosuppressive therapies * conditions contraindicated for or potentially limiting ability to conduct NFR and/or cold pressor test (e.g. Raynaud's syndrome; seizures; prior MI; respiratory conditions; leg/hip nerve damage; BMI ≥ 32) * sleep disorders other than insomnia * dementia or cognitive impairment * history of schizophrenia or bipolar I disorder; current or recent history (within 3 months) of major psychiatric disorders * current depressive symptomatology or current suicidality * active substance dependence * untreated hypertension * use of antidepressants (stable use for 3 months okay), antipsychotics, mood stabilizers, sedative-hypnotics, opiate analgesics