Association of systemic lupus erythematosus with angiographically defined coronary artery disease: a retrospective cohort study

Abstract

Objective: To determine if systemic lupus erythematosus (SLE) is associated with a higher prevalence of coronary artery disease (CAD) in select patients undergoing coronary angiography. We compared the extent of angiographic abnormalities, CAD risk factors, and all-cause mortality in SLE patients with non-SLE controls.

Methods: We identified SLE patients (n = 86) and controls matched by sex and year of cardiac catheterization (n = 258) undergoing cardiac catheterization for the evaluation of CAD (median followup duration of 4.3 years). Multivariable logistic regression was used to determine if SLE was associated with obstructive CAD, defined as ≥70% stenosis in a major epicardial coronary artery. Risk-adjusted survival differences between the 2 groups were assessed using Cox proportional hazards modeling.

Results: The SLE patients (85% women) were younger than the non-SLE patients (median age 49 years versus 70 years; P < 0.001) and were less likely to have diabetes mellitus and hyperlipidemia, but had similar rates of hypertension (70% versus 71%; P = 0.892). In unadjusted analyses, SLE and non-SLE patients had similar rates of obstructive CAD by angiography (52% versus 62%; overall P = 0.11). After adjustment for known CAD risk factors, SLE was associated with a significantly increased likelihood of CAD (odds ratio 2.24 [95% confidence interval (95% CI) 1.08-4.67]). SLE was also associated with a nonsignificant increase in all-cause mortality (hazard ratio 1.683 [95% CI 0.98-2.89], P = 0.060).

Conclusion: In this selected population, SLE was significantly associated with the presence of CAD as defined by coronary angiography, the gold standard for assessing flow-limiting lesions in this disease. The patients with SLE showed a similar severity of CAD as the controls despite having less than half the rate of diabetes mellitus and being 20 years younger.

Figure 1

SLE and control subject selection. *ICD-9 code 710.0: SLE; ** DDCD: Duke Databank for Cardiovascular Diseases; ^† Reason for exclusion: 65 dates out of range, 32 congenital heart diseases, 57 scleroderma overlap syndrome, 70 valvular heart diseases, 151 indication for cardiac catheterization not ischemic heart disease, 219 repeat cardiac catheterization records (only 1^st cardiac catheterization performed during the specified time frame included in analysis) ^‡ Reason for exclusion: 1,885 congenital heart disease; 18,141 missing data; 21,379 indication for cardiac catheterization not ischemic heart disease;386 heart transplant; 6,073 with rheumatoid arthritis, scleroderma, polymyositis, dermatomyositis, vasculitis, or psoriasis; 45,388 repeat cardiac catheterization records (only 1^st cardiac catheterization performed during the specified time frame included in analysis)

Figure 2

Comparison of all-cause mortality for patients with SLE (N=86) and controls (N=258) in the unadjusted and adjusted settings (A) Kaplan-Meier plots of the probability of survival in the SLE and control groups (log-rank survival, p=0.712) (B) Adjusted survival plots for the probability of survival after adjusting for age, ejection fraction, diabetes, hyperlipidemia, glomerular filtration rate (GFR), non-cardiac Charlson comorbidity index, and extent of coronary artery disease in the SLE and control groups (p=0.060)