I thought I should go back and answer this question. For those of you with arthritis the answer is obvious. But if you do not have arthritis you may not understand how difficult it is to sleep during a flare up of arthritis.
Depending upon which joints are affected by arthritis, you may not be able to sleep due to back discomfort or pain in your hip, knee or ankle. Sometimes its the small bones in the hands or neck. Arthritis makes finding that comfortable position for catching a few Zs almost impossible.
To make matters worse, arthritic pain causes sleep deprivation. This creates a cyclic pattern. Sleep deprivation is associated with increased the perception of pain. So maybe the pain is just annoying but after several sleepless nights your ability to tolerate the pain decreases. What was annoying becomes frustrating and difficulty to live with.
In addition sleep deprivation increases mediators of inflammation. People who fail to get adequate amounts of sleep have elevated levels of C-reactive protein, fibrinogen and IL-6.