The effect of systemic psoriasis therapies on the incidence of myocardial infarction: a cohort study.

BACKGROUND: Psoriasis confers an independent risk of cardiovascular disease that is likely to be related to systemic inflammation. Anti-inflammatory treatment could theoretically reduce the risk of cardiovascular disease, and initial data suggest that treatment may reduce the incidence of cardiovascular risk factors.
OBJECTIVES: To determine the impact of anti-inflammatory therapy on the risk of acute myocardial infarction (MI) in patients with moderate-to-severe psoriasis.
METHODS: Cohort study using administrative and pharmacy claims data from a large U.S. insurer comparing patients with psoriasis aged ≥ 18 years receiving systemic immunomodulatory therapies (methotrexate, ciclosporin, alefacept, efalizumab, adalimumab, etancercept and infliximab) with a control group treated with ultraviolet B phototherapy that has limited systemic anti-inflammatory effects. The risk of acute MI was calculated using a proportional hazards model while controlling for sex, age, hypertension, hyperlipidaemia, diabetes and depression. Significant interaction terms were included in the final model.
RESULTS: The study group included 25,554 patients with psoriasis receiving systemic treatment or phototherapy. There was a trend towards an increased risk of MI in the systemic treatment group but not a significant difference in overall MI risk [hazard ratio (HR) 1·33, 95% confidence interval (CI) 0·90-1·96]. Additionally, there was a significant interaction with age: in patients under 50 years the HR for MI if receiving systemic therapy was 0·65 (95% CI 0·32-1·34), and in patients aged 50-70 years it was 1·37 (95% CI 0·79-2·38).
CONCLUSIONS: Overall, there does not appear to be a reduced risk of MI in patients with psoriasis receiving systemic therapy compared with a group undergoing phototherapy. The risk of MI may vary by age.