Importance: Monoclonal antibodies (mAbs) targeting calcitonin gene-related peptide (CGRP) or its receptor (anti-CGRP mAbs) offer effective migraine-specific preventive treatment. However, concerns exist about their potential cardiovascular risks due to CGRP blockade.
Objective: To compare the incidence of cardiovascular disease (CVD) between Medicare beneficiaries with migraine who initiated anti-CGRP-mAbs vs onabotulinumtoxinA in the US.
Design, setting, and participants: This retrospective, sequential cohort study was conducted among a nationally representative population-based sample of Medicare claims from May 2018 through December 2020. Data analysis was performed from August to December 2023. This study included fee-for-service Medicare beneficiaries aged 18 years or older with migraine who initiated either anti-CGRP mAbs or onabotulinumtoxinA. Beneficiaries who had a history of myocardial infarction (MI), stroke, cluster headache, malignant cancer, or hospice service within a 1-year baseline period prior to treatment initiation were excluded. To minimize channeling bias from new drug introductions and time-related bias due to the COVID-19 pandemic, 5 cohorts were established, representing sequential 6-month calendar intervals based on the initial prescription or date of index anti-CGRP mAbs or onabotulinumtoxinA use.
Exposure: Anti-CGRP mAbs vs onabotulinumtoxinA.
Main outcomes and measures: The primary outcome was time to first MI or stroke. Secondary outcomes included hypertensive crisis, peripheral revascularization, and Raynaud phenomenon. The inverse probability of treatment-weighted Cox proportional hazards models were used to compare outcomes between the 2 treatment groups.
Results: Among 266 848 eligible patients with migraine, 5153 patients initiated anti-CGRP mAbs (mean [SD] age, 57.8 [14.0] years; 4308 female patients [83.6%]) and 4000 patients initiated onabotulinumtoxinA (mean [SD] age, 61.9 [13.7] years; 3353 female patients [83.8%]). Use of anti-CGRP mAbs was not associated with an increased risk of composite CVD events (adjusted hazard ratio [aHR], 0.88; 95% CI, 0.44-1.77), hypertensive crisis (aHR, 0.46; 95% CI, 0.14-1.55), peripheral revascularization (aHR, 1.50; 95% CI, 0.48-4.73), or Raynaud phenomenon (aHR, 0.75; 95% CI, 0.45-1.24) compared with onabotulinumtoxinA. Subgroup analyses by age group and presence of established non-MI or stroke CVD showed similar findings.
Conclusions and relevance: In this cohort study, despite initial concerns regarding the cardiovascular effects of CGRP blockade, anti-CGRP mAbs were not associated with an increased risk of CVD compared with onabotulinumtoxinA among adult Medicare beneficiaries with migraine, who were predominantly older adults or individuals with disability. Future studies with longer follow-up periods and in other populations are needed to confirm these findings.