A study by researchers at The George Institute for Global Health in Sydney reveals that almost all classes of antihypertensive medications (alpha-blockers, angiotensin II receptor blockers, ACE inhibitors, beta-blockers and calcium channel blockers) have some ability to reduce the frequency of days with headache in people with migraine.
This first known large-scale review of international studies on the positive effect of blood pressure (BP) medicines across all classes in preventing migraine shows these common drugs could be used much more widely, at low cost, than is the case with current practice.
The meta-analysis was published in the journal, Cephalalgia and included 50 trials of more than 4300 people, with BP-lowering medication on average reducing the number of headache days experienced per month by about one day on top of the average placebo effect.
“For countries where new migraine medications are expensive, limited by prescribing criteria or not available at all – covering all countries to some extent – this study shows that common BP medicines, which GPs are comfortable prescribing, can be an important preventative measure for patients with migraine or severe headache episodes,” says the study’s Joint Principal Investigator, Dr Cheryl Carcel, Senior Research Fellow at The George Institute and Conjoint Senior Lecturer, Faculty of Medicine, UNSW Sydney.
“Moreover, while we can see from the analysis that the effect is true for almost all types of BP medicines, this is not reflected in the current clinical guidelines, which specify just one or two types (such as beta-blockers) but not the full range of therapies that could be useful.”
Joint Principal Investigator and former GP, Dr Faraidoon Haghdoost adds: “Around 90 per cent of people with migraine can be managed in general practice, where the goal is to prevent as many episodes as possible because of the disabling impact they have on the patient’s quality of life.
“The good news is that blood pressure medications are widely available at low cost, with many available in generic forms, presenting a trusted treatment option alongside other preventive measures such as avoiding triggers and making lifestyle changes.
“The number of people living with headache disorders is enormous and common treatments given once an episode has taken hold can have side effects that in themselves present problems, such as drowsiness or weight gain.
“Whereas BP meds can prevent episodes without a significant side effect burden.”
The results of the study also indicated that not all BP medications are equally effective in preventing migraine.
The George Institute team is soon to publish a further review to give more insight into which of the various mechanisms is best.