Sarcoidosis not uncommon in systemic sclerosis

The occurrence of sarcoidosis in patients with systemic sclerosis (SSc) is rare but seems to be more frequent when compared to the general population, reveals a study.

Additionally, sarcoidosis is associated with pulmonary, lymph node, cutaneous, joint, and hepatic involvement, while patients with SSc‒sarcoidosis overlap syndrome are at higher risk of stroke but with no differences in survival.

In this retrospective cohort study, the authors compared SSc patients with and without sarcoidosis, all of whom fulfilled the American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for SSc. Sarcoidosis was confirmed by physician diagnosis or biopsy.

Time from diagnosis to all-cause mortality was the primary outcome. Kaplan-Meier curves were used to assess survival among patients.

A total of 1,977 patients were included, of whom 1,971 had SSc and six with SSc-sarcoidosis (prevalence, 0.30 percent). Sarcoidosis usually appeared before SSc (66.66 percent), and its most common manifestations were pulmonary (66.66 percent), lymphadenopathy (66.66 percent), arthritis (50 percent), cutaneous (33.33 percent), and hepatic (16.66 percent).

Among patients with SSc and SSc-sarcoidosis, the female-to-male sex ratios were 4:5 vs 5:1, and the median ages of SSc onset were 48.3 vs 43.8 years, respectively.

Patients with SSc-sarcoidosis were more likely to have interstitial lung disease (66.66 percent vs 35 percent) and pulmonary hypertension (50 percent vs 24.91 percent) and less likely to develop abnormal nailfold capillaries (16.66 percent vs 34.7 percent) and digital ulcers (16.66 percent vs 33.33 percent), but the differences were not statistically significant.

Notably, patients with SSc-sarcoidosis appeared to have an increased frequency of stroke (relative risk, 8.59, 95 percent confidence interval, 1.02‒72.00).

The median survival rates for SSc-sarcoidosis and SSc were 23.4 years and 18.6 years, respectively, with no differences in survival curves (log-rank test, p=0.55).