Background Atherosclerosis is a leading cause of cardiac and non-cardiac related morbidity and mortality in SSc1. It is believed to occur secondary to chronic inflammation, altered lipid profiles and function, development of autoantibodies, and endothelial dysfunction. There is increasing evidence that atherosclerosis occurs prematurely in systemic sclerosis 2–3.
Objectives The aim was to describe the parameters of subclinical vascular changes [Carotid Intima Media Thickness (cIMT), Flow Mediated Dilatation (FMD), Ankle Brachial Pressure Index (ABPI)] in patients with systemic sclerosis and compare them with age and sex matched controls.
Methods 50 patients of systemic sclerosis aged 20–50 years were selected and compared with the same no. of age and sex matched controls. Patients with diabetes, hypertension, dyslipidemia, smoking and thyroid disorders were excluded. cIMT was calculated using a linear probe (L 12–5 MHz) on a Philips iU 22 ultrasound machine at a distance of 2 cm from the carotid bulb. A mean of the left and right cIMT was calculated. Endothelium-dependent FMD of brachial artery was expressed as the percentage change in brachial artery diameter from baseline. The average of the right and left brachial artery FMD was studied. ABPI of both right and left lower limb was measured (using Doppler) and the average value of ABPI was considered.
Results The cases and controls were well matched in terms of age, blood pressure, B.M.I, renal and liver functions, and lipid profiles. 16 patients had limited cutaneous SSc while 36 had diffuse cutaneous SSc. cIMT was significantly more in SSc patients as compared to controls (0.585 mm vs 0.571 mm; p=0.001). FMD measurements in SSc patients were lower when compared to controls, but they did not achieve statistical significance (7.61% vs 8.03%; p=0.608). ABPI values were similar in SSc patients and controls (1.056 vs 1.036; p=0.398). cIMT did not show any correlation with age or duration of illness. ABPI showed significant inverse correlation with duration of illness (Rho= -0.385; p=0.006). However, none of these parameters varied as per the pattern of skin involvement (diffuse vs limited), presence or absence of digital infarcts or pulmonary fibrosis.
Conclusions cIMT is increased in patients with systemic sclerosis as compared to matched controls and may serve as a useful marker for detection of subclinical atherosclerosis in these patients. ABPI varies inversely with disease duration in patients with systemic sclerosis.
Zinger H, Sherer Y, Shoenfeld Y: Atherosclerosis in autoimmune rheumatic diseases-mechanisms and clinical findings. Clin Rev Allergy Immunol. 2009 Aug; 37 (1): 20–8.
Hettema ME, Bootsma H, Kallenberg CG: Macrovascular disease and atherosclerosis in SSc. Rheumatology (Oxford). 2008 May; 47(5): 578–83.
Mok MY, Chiu SS, Lo Y, et al: Coronary atherosclerosis using computed tomography coronary angiography in patients with systemic sclerosis. Scand J Rheumatol. 2009 38(5): 381–5.
Disclosure of Interest None declared