Seasonal variation of Raynaud's phenomenon secondary to systemic sclerosis

Patients with systemic sclerosis (SSc) were assessed for 12 months to quantify the seasonal variation in Raynaud's phenomenon (RP) in patients with an underlying connective tissue disease.

Eighteen patients with SSc (17 limited, 1 diffuse type) were studied. Raynaud's attacks were recorded in a daily diary for four 2-week periods at 3 month intervals. Daily number and duration of attacks and overall severity of RP were calculated for each 2-week period. Mean daily temperatures, measured and perceived, were obtained for each period.

In winter, patients had a mean of 2.9 attacks/day (SD +/-1.1), daily duration 70 minutes (SD +/-48) and a severity of score of 4.1 (SD +/-2.0) out of 10. All 3 variables correlated with ambient outdoor temperature and varied significantly over the 12 months (p<0.001) with mean reductions of 48, 50, and 56% respectively from winter to summer. Only 3 of 18 patients reported no attacks during the summer period. The mean measured and perceived outdoor temperatures increased from winter to summer by 10.6 and 14.3 degrees C, respectively.

For patients with SSc, RP is a problem throughout the year. Symptoms may be reduced by about 50% in the summer months, but few patients experience complete relief.