Abrupt temperature change triggers arthralgia in patients with juvenile rheumatoid arthritis.

BACKGROUND AND PURPOSE Juvenile rheumatoid arthritis (JRA) is the most common form of arthritis in children and affects both quality of life and school attendance. Weather and temperature conditions are believed to affect joint pains; however, very few studies have investigated this issue. This study examined the association between joint pain in JRA patients and weather conditions. METHODS The daily pain ratings of 52 patients previously diagnosed with JRA were recorded on visual analog scales over 4 months beginning January 1, 2004. These ratings were then compared with weather data to evaluate possible correlation between these two factors. RESULTS Twenty nine patients kept daily records during the first 2 months. There was no positive correlation between weather parameters (such as temperature, humidity, and barometric pressure) and pain ratings. Interestingly, the pain rating significantly increased the day after the advent of a cold wave (sign test, p<0.01; Wilcoxon signed ranks test, p=0.001). The number of patients who experienced joint swelling was not related to weather conditions. Twenty one participants continued maintaining the diaries during the next 2 months. The patients reported higher pain levels in the first 2 months during the cold wave period than in the next 2 months when the cold wave period had ended (p<0.001). CONCLUSION A dramatic weather change such as a sudden cold wave might influence the experience of joint pain.