Atherosclerotic cardiovascular disease and dermatomyositis: an analysis of the Nationwide Inpatient Sample survey

INTRODUCTION Increased rates of cardiovascular disease are implicated in several rheumatologic diseases. Our aim was to characterize dermatomyositis hospitalizations and evaluate cardiovascular-associated mortality in this patient population. METHODS We examined the frequency and mortality rates of several atherosclerotic cardiovascular diagnoses and procedures among hospitalized adult patients with dermatomyositis using data from the US Nationwide Inpatient Sample (NIS) from 1993 to 2007. We compared the odds of death among hospitalized dermatomyositis patients with each cardiovascular diagnosis or procedure to those without, as well as to controls with cardiovascular diagnoses, using logistic regression. RESULTS A total of 50,322 hospitalizations of dermatomyositis patients occurred between 1993 and 2007 (mean age 58 years, and 73% female). Of all dermatomyositis hospitalizations, 20% were associated with a concurrent atherosclerotic cardiovascular diagnosis or procedure. The overall in-hospital mortality was 5.7%. Dermatomyositis patients with any associated atherosclerotic cardiovascular diagnosis or procedure were twice as likely to die during the inpatient stay compared to dermatomyositis patients who did not have atherosclerotic cardiovascular disease (OR=2.0 95% CI 1.7-2.5, p<0.0001). The odds ratio for death in patients with both dermatomyositis and cardiovascular disease compared to controls with cardiovascular disease alone was 1.98 (95% CI 1.57-2.48) in multivariate adjusted models. CONCLUSIONS Approximately one fifth of dermatomyositis hospitalizations in the US were associated with an atherosclerotic cardiovascular diagnosis or procedure. These patients have double the risk of in-hospital death in comparison with controls and dermatomyositis patients without a cardiovascular diagnosis, making identification of these groups important for both prognostic purposes and clinical care.