Examining Associations Between Sex, Autoantibodies, and Microangiopathy in Systemic Sclerosis

Sex was not found to affect the degree of microangiopathy in systemic sclerosis (SSc), and associations between SSc-specific autoantibodies and degree of microangiopathy cannot be conclusively determined using existing literature, according to results of a systematic review published in Arthritis Care and Research.

Dysregulation of the immune system and microangiopathy play important roles in SSc pathogenesis, and the degree of microangiopathy is used as a diagnostic and prognostic tool for this disease. However, factors that trigger vascular injury in SSc have not yet been identified.

Investigators performed a standardized search of Cochrane, EMBASE, PubMed, and Web of Science databases to identify studies in which microangiopathy of the hand and the expression of autoantibodies specific to SSc were evaluated in adults with SSc (n=11). A second search of these databases was conducted to identify studies in which microangiopathy of the hand was evaluated in adults with SSc in relation to sex (n=6). The meta-analysis examining the presence of autoantibodies and microangiopathy could not be conducted due to heterogeneity and the use of different outcome measures across the 11 studies. In the 6 studies investigating associations between sex and microangiopathy, heterogeneity prevented a meta-analysis.

An association was established between autoantibodies and microangiopathy in 2364 patients (vs 742 patients in which no associations were detected). In an analysis in which only the high-quality studies were included, the presence vs absence of an association between autoantibodies and microangiopathy was established in 241 vs 390 patients, respectively.

Of the 6 studies in which associations between sex and microangiopathy were examined, in 5 studies (1614 women and 204 men), sex and microangiopathy were not found to be associated. The only study in which a sex difference was established for the presence of microangiopathy had an unbalanced participant group with 44 women and 5 men, with men more often treated with cyclophosphamide.

“Contradictory results were found about the association between autoantibodies and microangiopathy and no firm conclusions can be drawn, noted the study authors. “We believe that the identification of factors possibly affecting microangiopathy is of relevance to elucidate the pathophysiology of microangiopathy and also for clinical risk stratification. Therefore, in consideration of the paucity of available data, and especially derived from high-quality research, we advocate further prognostic cohort studies to evaluate factors contributing to the degree of microangiopathy in SSc.”

Reference

van Leeuwen NM, Ciaffi J, Schoones JW, Huizinga TWJ, de Vries-Bouwstra JK. The contribution of sex and auto-antibodies to microangiopathy assessed by nailfold videocapillaroscopy in systemic sclerosis: a systematic review of the literature [published online January 21, 2020]. Arthritis Care Res (Hoboken). doi:10.1002/acr.24149