Triptans for Migraine: Balancing Potential Vascular Risk With Meaningful Benefit

Migraine currently stands as the second highest cause of disability in the world, first among young adults, with an estimated global prevalence of 15% and accounting for 5% of all years lived with disability, ¹ highlighting the need for treatments that are both effective and widely available.

Triptans, selective 5‐HT_1B/1D agonists with varying 5‐HT_1F activity, have been on the market for more than three decades and remain among first‐line therapy options for acute migraine attacks. Differences between available triptans in bioavailability and half‐life mainly translate into modest differences in clinical efficacy across agents and formulations. ²

Before triptans, ergot alkaloids were widely used for migraine treatment. Ergot, the rye fungus responsible for historical outbreaks of ergotism (“St. Anthony’s Fire”), was known to cause vasospastic ischemia and gangrene, which informed the cautious use of ergotamine for migraine because of its nonselective serotonergic vasoconstrictive effects. The antimigraine benefit was believed to result from constriction of dilated cranial arteries, and therefore, triptans were developed as selective 5‐HT₁ receptor agonists intended to preferentially produce cranial vasoconstriction. ³ Because 5‐HT₁ receptors are also expressed in coronary arteries, early concerns focused on possible triptan‐induced vasospasm leading to myocardial infarction or stroke, and vascular disease was therefore listed as a contraindication in the original marketing authorization. These contraindications persist and are reflected in current Food and Drug Administration product labeling, which lists ischemic coronary artery disease, stroke or transient ischemic attack, and related vascular conditions, including peripheral vascular disease and uncontrolled hypertension, as contraindications to triptan use. Contemporary data, in contrast to prior beliefs, indicate that the antimigraine effects of triptans extend beyond vasoconstriction, including inhibition of the release of vasoactive neuropeptides from nociceptive perivascular trigeminal fibers and suppression of pain signal transmission within the trigeminal nucleus caudalis of the brainstem. ⁴ Selective 5‐HT_1F agonists, which lack vasoconstrictor effects, are also effective for the treatment of migraine attacks. ² Human studies suggest only small effects of triptans on cerebral ⁵ and coronary ⁶ arteries at therapeutic exposures. Also, most ischemic strokes and myocardial infarctions arise from plaque rupture with thrombosis or embolism rather than vasoconstriction, ⁷ making a direct causal pathway from triptan use to major vascular events mechanistically less compelling. Consistent with this, large observational studies have not demonstrated an increased risk of acute ischemic stroke or myocardial infarction among patients who treat migraine attacks with triptans. ⁸ , ⁹ Whether this reflects a genuinely negligible vascular risk or preferential prescribing of triptans to lower‐risk patients remains debated. ⁷ , ¹⁰

Adding to this ongoing discussion, Kalapura and colleagues in this issue of the Journal of the American Heart Association (JAHA) report a large US claims‐based analysis. ¹¹ Using Merative MarketScan data, they compared triptan initiators with noninitiators in a new‐user cohort of adults with migraine. For ischemic stroke, overlap‐weighted incidence rates were 3.4 versus 1.7 per 1000 person‐years, yielding an adjusted hazard ratio of 2.4. The corresponding absolute risk difference was roughly 0.17% per year, equivalent to an approximate number needed to harm of 588 per year. The authors also evaluated intracranial hemorrhage and retinal arterial events: hemorrhage risks were higher among initiators, whereas estimates for retinal outcomes were close to null. To complement the between‐individual cohort analysis, they conducted a within‐individual self‐controlled risk‐interval analysis among initiators and observed higher odds of ischemic stroke in the 14‐ and 90‐day periods after initiation compared with the same windows 1 year earlier.

Several features strengthen this report: it is large and contemporary, outcomes are clinically meaningful, and absolute measures accompany relative estimates. The addition of a self‐controlled analysis is a strength because it removes unmeasured between‐individual confounding by using each patient as their own control and focuses on short postinitiation windows. This matters because clinicians often avoid prescribing triptans to patients with high cardiovascular risk, so users and nonusers differ at baseline in ways that are hard to measure and adjust. ¹⁰ However, the study also has a number of limitations that affect the interpretation of the triptan–vascular event association. Because triptan users are indexed at their first prescription whereas nonusers are indexed at the midpoint of their first eligibility year, the 2 groups are not observed from a common starting point. Individuals who later initiate must, by definition, remain event free up to their first fill. Depending on how long initiation is delayed and how baseline risk changes between eligibility and the chosen index dates, this differential indexing can shift the initiator–noninitiator hazard ratio in either direction. This is potentially important because stroke risk after a new migraine diagnosis is markedly higher during the first year than in subsequent years. ¹² For example, if initiators often fill a first triptan prescription within 6 months of diagnosis, their follow‐up time includes more of this early high‐risk period than that of noninitiators indexed at about 6 months, which would tend to overestimate any harmful association. Triptans are short acting and used intermittently, so an “ever‐exposed since first fill” estimand does not match pharmacology, and short postindex risk windows are more informative. A self‐controlled analysis helps by removing time‐invariant confounding (ie, confounding that remains stable over time), but the version used here is initiation anchored: postinitiation windows are compared with the same calendar windows 1 year earlier. This design can still be affected by changes across the intervening year and by factors linked to the decision to initiate treatment; an event‐anchored self‐controlled design, using referent windows shortly before initiation, addresses these issues more directly. ¹³

Putting these findings into context, a conceptually similar registry‐based study, using nationwide Danish registry data, applied an event‐anchored case‐crossover design to test whether first‐ever triptan redemptions clustered immediately before major vascular events. ¹⁰ This self‐controlled approach compares short hazard windows just before the event with several nearby referent windows in the same individual, which reduces between‐individual confounding and, by design, avoids time‐zero misalignment. The Danish study found higher short‐term odds of myocardial infarction and ischemic stroke after first‐ever triptan use, whereas absolute numbers were very small and exposed cases tended to be older with higher cardiovascular risk. Kalapura and colleagues observed directionally similar short‐window estimates in a within‐individual analysis anchored on initiation, supporting consistency despite methodological differences.

Both studies, however, share important limitations that deserve explicit emphasis. First, exposure is inferred from prescription redemption, and we cannot determine whether or when the medication was actually taken. The 14‐day window used in both papers therefore serves as a pragmatic proxy for timing of exposure rather than a verified dosing interval, although it is reasonable to assume that initial prescriptions are often filled by individuals experiencing recurrent migraine attacks that require treatment. Second, protopathic bias is possible: triptans may be prescribed for symptoms that are, in fact, early manifestations of the vascular event. Cerebrovascular events can present with migraine‐like headache, and misdiagnosis of transient ischemic attack or minor stroke as “migraine” in the emergency department is not uncommon. ¹⁴ Consistent with this, patients discharged from the emergency department with a “headache” diagnosis have a 3‐ to 4‐fold higher risk of stroke in the subsequent month compared with patients presenting with kidney colic or back pain, with the excess concentrated in the first 10 days. ¹⁵ Myocardial ischemia may also present as migraine‐like headache, providing another route to protopathic bias. ¹⁶

Taken together, the available evidence indicates that triptans are generally safe, but they are unlikely to be completely free of vascular risk, particularly in people who already have a high baseline risk of ischemic events. A helpful way to interpret these findings is to compare them with other everyday exposures. Nonaspirin NSAIDs are associated with small to moderate increases in myocardial infarction and stroke, typically in the range of 20% to 50% during early treatment, with higher estimates for diclofenac and some COX‐2 (cyclooxygenase‐2) inhibitors and lower estimates for naproxen. ¹⁷ Among patients with prior myocardial infarction, NSAID use is linked to substantially higher absolute event rates, with hazard increases around 45% to 55% and especially early signals for diclofenac. ¹⁸ Transient infections confer even larger short‐interval vascular risks: acute respiratory infections are associated with several‐fold elevations in myocardial infarction and stroke over the subsequent days to weeks, including roughly a 6‐fold increase in myocardial infarction within 7 days of laboratory‐confirmed influenza. ¹⁹ Viewed against these benchmarks, the short‐interval association seen around triptan initiation in self‐controlled analyses appears modest for most users, though it remains clinically relevant for those with substantial baseline cardiovascular risk.

What are the clinical implications? Triptans remain a cornerstone of acute migraine therapy. Although the average effect size for acute migraine treatment is moderate, ²⁰ it is often sufficient to restore function during otherwise disabling attacks, and a substantial proportion of patients experience marked relief that meaningfully improves quality of life. Risk should be communicated clearly and in absolute terms. In the nationwide Danish case‐crossover study, the authors estimated that, taken at face value, ∼1 in 30 000 new users experienced a vascular event attributable to triptans, ¹⁰ underscoring how small the absolute risk appears in contemporary practice. In that study, the short‐interval signal was largely confined to older individuals and those with unfavorable cardiovascular profiles, whereas absolute risks in typical low‐risk users were very low. In the present cohort, the absolute excess was roughly 0.17% per year in the weighted analysis—a magnitude that many patients may find acceptable given the disability associated with untreated migraine. For patients at increased cardiovascular risk, counseling should include discussion of this short‐interval signal, the generally low absolute event counts seen in population studies, and consideration of alternatives when appropriate.

Of note, how triptans might cause major vascular events is not established. As mentioned, most ischemic strokes and myocardial infarctions are not vasospastic in origin, and vasoconstrictor effects of triptans are small, so simple large‐artery constriction seems an unlikely explanation. New drugs for acute migraine treatment, gepants and ditans, are often described as free of vascular risk because they are not vasoconstrictors, yet they, directly or indirectly, inhibit the effects of vasodilator peptides with potential cerebrovascular and cardiovascular roles. Current data are reassuring in lower‐risk users but remain limited for patients with established vascular disease, so comparative safety of these drugs should be evaluated in dedicated studies. ²¹

Collectively, the new data suggest a modest association between triptan initiation and short‐term vascular events. The absolute excess appears small for most initiators and is concentrated among those with higher baseline risk. Triptans remain an appropriate and widely used option for acute migraine, with a safety profile that is generally acceptable. For many patients, the expected benefit will outweigh a small potential risk when treatment decisions are individualized. This balance is central to shared decision‐making in acute migraine care.

Disclosures

Anders Hougaard is Chair of the Headache and Vascular Disorders Special Interest Group of the International Headache Society and serves as Associate Editor of Headache, the Journal of the American Headache Society.