Levels of pain intensity and arthritic stiffness closely follow the rhythms of the body clock, reveals new research published in the November 2002 issue of Annals of the Rheumatic Diseases.
Researchers from the Centre of National Research on Disability and Rehabilitation Medicine asked 21 patients with osteoarthritis in their hands to rate their levels of pain and stiffness using validated scores at six points during the day – on waking, at bed-time, and every four hours in between for 10 days. Most of the patients were women, whose average age was 62. None was being treated with steroids.
At the same time points, the patients were asked to perform a manual dexterity test, consisting of picking up beads and feeding them into a container through a narrow tube. If they dropped any, they had to start again. The whole process was timed.
Pain and stiffness followed the body’s bio (circadian) rhythms, being greatest first thing in the morning and at bed-time, and lowest mid-afternoon (approximately 2:00 pm) for three-quarters of the patients.
Manual dexterity was also influenced by the levels of pain and stiffness, and changed throughout the day, peaking at approximately 3:00pm, and occurring within the zones of least overall pain (1:00 pm – 6:00pm) and stiffness (3:00 pm – 5:00pm).
The authors conclude that the predictability of pain and stiffness levels and the attendant dexterity should inform the scheduling of patients’ daily activities, and it could also be used to time drug treatments for maximum effect, they said.