• Myocardial Infarction
• Rheumatological Autoimmune Disorders
• Rheumatology Clinical Trials

• Myocardial Infarction
• Rheumatological Autoimmune Disorders
• Rheumatology
• Rheumatology Clinical Trials

Evidence of macrovascular involvement and premature atherosclerosis in patients with systemic sclerosis (SSc) has been emerging. The risk of myocardial infarction (MI) was found to be increased in patients with incident SSc in a large population-based study discussed by J. Antonio Avina-Zubieta, MD, PhD, University of British Columbia, Vancouver, Canada.

In SSc, cardiovascular disease is the leading non-SSc cause of death [Tyndall AJ et al BMJ 2010]. Previous studies in which a link between SSc and premature atherosclerosis was discovered did not adjust for medication use and other relevant confounders or they relied on selected populations, obscuring the true risk of MI in this population [Nordin A et al. Arthritis Res Ther 2013; Ngian GS et al. Ann Rheum Dis 2012].

Using administrative health data from all 4.7 million residents of British Columbia, Canada, Prof. Avina-Zubieta and colleagues sought to estimate the risk of MI in patients with incident SSc at the general population level and to assess time trends in the risk of MI in relation to the onset of SSc. Some 1245 patients with SSc were identified from the database. Each patient was matched to 10 controls from the general population based on birth year, sex, and calendar year of exposure, for a total of 12,678 controls. The risk of incident MI in the SSc cohort relative to the general population was adjusted for age, sex, and comorbidities. The mean Charlson comorbidity index was 1.1 in the SSc cohort and 0.3 in the matched controls. At the time of SSc diagnosis, mean patient age was ∼53 years. Consistent with the disposition of SSc, >80% of the study population were women.

Over an average follow-up of 3.5 years, incident MI occurred in 89 of the SSc group and in 289 controls, for an incidence rate of 20.2 per 1000 person-years among the SSc cohort and 5.3 per 1000 person-years among the controls. Using a multivariable adjusted model, the relative risk (RR) of incident MI was 4.1 (95% CI, 3.1 to 5.4) in the SSc cohort compared with the general population. The increased adjusted RR of MI in the SSc cohort remained significant on sensitivity analyses adjusting for potential unmeasured confounders (Table1).

When analyzed according to the follow-up period, the age- and sex-adjusted RR of MI among patients with SSc was highest within the first year of follow-up, at 8.2 (95% CI, 5.3 to 12.4; Table 2).

The increased RR of MI among patients with SSc was attenuated with longer duration of follow-up, to an age- and sex-adjusted RR of 3.1 during follow-up Years 1 through 5, and 1.4 with >5 years of follow-up.

When analyzed according to age, the adjusted RR of MI in SSc patients was highest in the group aged 45 to 59 years old (RR, 7.4; 95% CI, 3.5 to 15.7 compared with the group aged <45 years).

The findings support increased vigilance in cardiovascular disease prevention, surveillance, and risk modification in patients with SSc, said Prof. Avina-Zubieta.

• © 2013 MD Conference Express®