OBJECTIVE:

Few studies have focused on the association between coronary artery disease (CAD) and transfusion naïve thalassemia populations (this term means silent carrier, thalassemia minor or intermedia), who usually had less clinical manifestations and didn't require frequently blood transfusion.

DESIGN, SETTING AND PATIENTS:

This nationwide population-based cohort study involved analyzing data obtained between 1998 and 2010 from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified patients with thalassemia and selected a comparison cohort that was frequency matched with the patients with thalassemia according to age, sex, and diagnosis year at a ratio of 1 patient with thalassemia to 4 control patients. We analyzed the risks of thalassemia and CAD by using Cox proportional hazard regression models.

MEASUREMENTS AND MAIN RESULTS:

In this study, 1537 patients with thalassemia and 6418 controls were included. The overall risks of developing CAD were 1.5-fold in patients with thalassemia compared with those in the comparison cohort after adjustment for age, sex, and comorbidities. Patients with thalassemia and with comorbidities, including hypertension, diabetes, hyperlipidemia, and chronic obstructive pulmonary disease, were 3.73-fold more likely to develop CAD than those without thalassemia and comorbidity (95% confidence interval=2.41-5.79).

CONCLUSION:

This is the first large long-term cohort study of which the results showed that that transfusion-naïve thalassemia populations should be considered a crucial risk factor for CAD, even in patients with relatively mild clinical manifestations of thalassemia.