Prevalence and clinical correlates of pruritus in patients with systemic sclerosis: an updated analysis of 959 patients

Objectives. One previous study has estimated the prevalence of pruritus in SSc, but that study had important limitations due to a relatively small sample size. The present study updates the analyses of the previous study using a substantially larger patient sample. The objectives were to (i) document the proportion of patients who experience pruritus on most days overall and by disease duration and (ii) identify clinical correlates of pruritus. Methods. Patients from the Canadian Scleroderma Research Group Registry ≥1 year after registry enrolment were asked on two consecutive annual visits whether they had experienced pruritus in the past month on most days and underwent clinical history and medical examination. Multiple logistic regression was used to assess the association between sociodemographic and clinical variables and pruritus. Results. Among 959 patients, 42.6% reported pruritus. Of 693 patients with data for both visits, 333 (48%) did not report pruritus at either visit, 209 (30%) reported pruritus at both visits and 151 (22%) reported pruritus at one, but not the other, visit. The presence of pruritus was independently associated with greater skin involvement [odds ratio (OR) = 1.02, 95% CI 1.00, 1.04, P = 0.017] and greater gastrointestinal involvement (OR = 1.24, 95% CI 1.04, 1.48, P = 0.018). Conclusion. Pruritus is common in SSc across the course of the disease and has small but statistically significant associations with the degree of skin involvement and gastrointestinal system involvement.