Abstract

Background: Teriflunomide has been associated with an increased risk of hypertension. Real-world studies including adequate control groups are lacking. We hypothesized that patients with multiple sclerosis (MS) treated with teriflunomide would be at higher risk of developing hypertension than those treated with dimethyl fumarate. Methods: We conducted a cohort study linking the Danish Multiple Sclerosis Registry with national health registries during a 10-year period. Teriflunomide ( N = 2656) and dimethyl fumarate ( N = 2237) exposure was defined by the first treatment record lasting ⩾ 3 months, at which time follow-up started. We included 4893 adult patients without hypertension at baseline. Hypertension was defined as an International Classification of Diseases 10th Revision code for hypertension and by dispensed prescription drugs identified by the respective Anatomical Therapeutic Chemical codes. We used multivariable-adjusted Cox regression. Results: We found 40.6 (teriflunomide) and 13.1 (dimethyl fumarate) hypertension events per 1000 person-years. Compared to dimethyl fumarate-treated patients, patients treated with teriflunomide had a higher risk of developing hypertension (adjusted hazard ratio = 2.80; 95% confidence interval = 2.19–3.56). The number needed to harm was 16 and 9 at 3 and 5 years of follow-up, respectively. Conclusion: We found an increased risk of hypertension in adult patients with MS treated with teriflunomide.