Risk of myocardial infarction in canadian patients with psoriasis: a retrospective cohort study.

ABSTRACT

BACKGROUND: Studies have shown that psoriatic patients are at increased risk for myocardial infarction (MI) and stroke. There is a lack of data on MI risk in Canadian psoriatic patients. OBJECTIVE: To compare MI risk in Canadian psoriatic patients to that in control patients. METHODS: This was a retrospective cohort study using Quebec's health insurance database (2005-2010) comparing MI risk in psoriatic patients to that in matched controls. Severe psoriasis was defined as any diagnosed psoriatic patient who used phototherapy or oral or injectable psoriasis treatments. Adjustments were made for several MI risk factors. RESULTS: There were 31,421 patients in the psoriasis population, of which 5,159 had severe psoriasis. The unadjusted MI incidence rate per 1,000 person-years was 4.88 (95% confidence interval [95% CI] 4.50-5.20), 5.58 (95% CI 5.10-6.10), and 5.32 (95% CI 4.40-6.40) for the control and mild and severe psoriasis groups, respectively. After adjustments, the hazard ratio of MI was significantly higher for psoriatic patients than for controls (1.17; 95% CI 1.04-1.31). The hazard ratio was also significantly higher than for controls in the mild psoriasis group (1.18; 95% CI 1.05-1.33) but not in the severe psoriasis group (1.16; 95% CI 0.94-1.42). CONCLUSION: The relative MI risk is higher for Canadian psoriatic patients than for controls.