Clinical and Serological Associations of Subclinical Atherosclerosis in Systemic Sclerosis

Abstract

Background: While patients with systemic sclerosis (SSc) are predisposed to cardiovascular events, data regarding this from India is sparse. We analysed correlates of subclinical atherosclerosis in Indian patients with SSc. Methods: Patients with SSc fulfilling the 2013 classification criteria ( n = 61) were recruited after obtaining written informed consent. Clinical risk factors for cardiovascular disease (CVD) were assessed. A carotid ultrasound was performed to assess the mean carotid intima-media thickness (CIMT). Total and endothelial microparticles (EMP, positive for CD31 and CD146) were estimated from plasma. Serum cytokines known to play a role in atherosclerosis (interleukin-1β [IL-1β], tumour necrosis factor-alpha, IL-6 and IL-17) were assessed. Forty-one age- and sex-similar healthy controls were recruited for comparison. Clinical and serological risk factors for CVD were compared between SSc with and without carotid plaque. Linear regression analyses were conducted to identify predictors of CIMT and carotid plaque in SSc. Results: Patients with SSc had lower body-mass index than healthy controls, however, had higher CIMT, higher serum IL-1β, IL-6, total microparticles and EMP than control subjects. SSc with carotid plaque ( n = 13) were older, and more likely to be male, but demonstrated no differences in serological markers of CVD. On multivariable-adjusted regression analyses, age was the only significant predictor of CIMT in SSc and male sex was the only significant predictor of carotid plaque in SSc. Conclusions: Carotid plaques were present in one-fifth of young patients with SSc. Older age and male sex predicted a higher risk of subclinical atherosclerosis in SSc.