It is a widely held popular belief that the weather can affect the level of pain felt by patients with rheumatic diseases such as rheumatoid arthritis, osteoarthritis and fibromyalgia. It is also well known that some patients find relief by moving to a warm, dry climate. Medical science, however, has not accepted the idea that there could be a connection between rheumatic pain and weather conditions. This maybe about to change. A group of Argentine medical researchers have just completed a fascinating study designed to investigate the connection. Their study was carried out in the city of Cordoba, which has a mild Mediterranean-type climate where differences between indoor and outdoor conditions are small. A total of 151 patients took part. Eighty-two had rheumatoid arthritis, 52 had osteoarthritis, and 17 had fibromyalgia; the trial also included 32 controls free of rheumatic disease. All study participants kept a daily log concerning their pain, when it was worst, what joints were affected, etc. from January 1 to December 31, 1998. They were not told what purpose the daily log served. Meanwhile the researchers received four weather readings a day of temperature, barometric pressure, and relative humidity in the area inhabited by the study group. A detailed statistical analysis of the collected data revealed some highly significant correlations (p< 0.001). Pain severity in rheumatoid arthritis patients was found to increase with lower temperature, higher atmospheric pressure, and higher humidity – so a cold, rainy day is definitely not a good one for these patients. Osteoarthritis patients felt more pain when the temperature was low and the humidity high while fibromyalgia patients fared worse if the temperature was low and the barometric pressure high. There was no correlation between weather conditions and pain in the controls. The researchers also found no correlation between climate variables and pain, except for humidity when measured five days before and five days after the days of painful episodes. They conclude from this that it is not overall climate, but rather climate changes that affect patients with rheumatic disorders.
Strusberg, Ingrid, et al. Influence of weather conditions on rheumatic pain. Journal of Rheumatology, Vol. 29, February 2002, pp. 335-58