P9 Coronary artery calcification on thoracic CT is associated with pulmonary hypertension and is an independent predictor of mortality in systemic sclerosis

ObjectiveCoronary artery calcification (CAC) on thoracic computed tomography (CT) is a known biomarker of coronary artery disease and mortality. Systemic Sclerosis (SSc) is a pro-inflammatory condition; microvascular inflammation is increasingly hypothesised to drive pulmonary hypertension (PH) in SSc. Inflammation is also a driver of CAD. We hypothesised that CAC would be prevalent and associated with mortality in SSc.MethodsRetrospective analysis of 262 CTs in SSc patients from a prospectively maintained clinical database at a tertiary Rheumatology/PH service March 2007-March 2021 (mean age 65±12, 14% male). 86/262 (33%) had interstitial lung disease (ILD), 128/262 (49%) had PH. CTs were re-reviewed for CAC; severity was graded by experienced readers using a four-point scale per vessel and summed for total CAC score (CACS).ResultsCAC was present in 152/265 (57%). All-cause mortality occurred in 65/262 (25%) patients over mean 5±3 years follow-up. Presence of CAC was associated with >2 times risk of death (Hazard ratio [HR] 2.41; 95% CI 1.3–4.5; p=0.006), correcting for age and gender. PH was predictive of mortality (HR 3.6, 95%CI 1.4–9.3, p=0.007), corrected for age and gender; ILD was not (HR 1.3, 95% CI 0.8–2.2, p=0.34). PH was significantly associated with CAC (X2=7.7, p=0.009). In contrast, ILD had no significant association with CAC (X2=0.57, p=0.81).ConclusionCAC is common in SSc and is associated with PH. PH and CAC are predictors of mortality in SSc and both have a hypothesised pro-inflammatory driver. Further validation is required to assess the potential role for anti-inflammatory therapies.