They’re painful and disconcerting, but don’t get as much press as many other health problems. Headache disorders are a very big deal, and they already affect 52% of the global population, with 14% reporting migraines, according to a new study. Researchers updated a previous review from 2007 and found the problem is getting significantly worse.

Headache disorders are one of the major public health concerns globally and in all countries and world regions, according to the Global Burden of Disease (GBD), a global review that measures epidemiological levels and trends. In its 2019 iteration, migraine alone was second among the causes of disability, especially affecting young women — and there are plenty of other headache-inducing conditions.

But GBD may not even tell the whole story; it uses epidemiological studies as its only source for headache disorders and researchers at the Norwegian University of Science and Technology see this as a potential problem, as headache epidemiology is a relatively young field of research. Studies have had methodological problems in the past, despite recent improvements, and this could introduce biases and other problems in analyzing large-scale data.

Building on a previous report from 2007, Lars Jacob Stovner and colleagues reviewed 357 publications between 1961 and the end of 2020 to estimate the global prevalence of headaches. They also measured the differences in methods across the reviewed studies, seeking to estimate headache prevalence on a global scale.

“This study is an update of the literature from our 2007 publication. Also, we now wished to study in more detail how the methodology used for measuring headache prevalence influenced the results,” Stovner told ZME Science. “The more general motivation was to influence health services and decision-makers in health-care.”

A growing problem

Back in 2007, Stovner and his team found that 46% of the global adult population suffered from headaches in general, with 11% experiencing migraines. Now, based on the publications reviewed, the problem has worsened, with 52% of the population experiencing a headache disorder within a given year and 14% reporting migraines.

“Almost 5% (1 in 20) of the population have headaches more than half of the days. Each day 15% of all have a headache, and in almost half of them this is migraine. Females are much more affected than men,” Stovner told ZME Science. “Headaches and migraines are a gigantic public health problem, that should be taken seriously by doctors and decisions-makers.”

The updated review showed that all types of headaches were more common in females than males, especially migraines (17% in females vs 8.6% in males) and headaches for 15 or more days per month (6% in females vs 2.9% in males). Previous studies have linked this to changes in hormones, which can trigger more headache events.

While the results help better understand the scale of the problem, the authors acknowledge that most of the studies they reviewed were from high-income countries with good healthcare systems. This means the review doesn’t necessarily reflect global trends. For the data to be representative, the authors chose studies that sampled participants outside of clinical settings.

Tackling headaches

Headache disorders come at the cost of personal suffering, reduced quality of life, and even financial costs. When they are repeated, they can damage family and social life as well as employment. Also, coping with a chronic headache disorder can lead to other illnesses. For example, depression is more common in people who have migraines than in healthy individuals.

To the World Health Organization (WHO), there are a set of barriers to tackling the problem, the main one being a lack of knowledge among healthcare providers. Only four hours of undergraduate medical education are used to instruct on headache disorders. Also, only 40% of individuals with migraines or tension-type headaches are professionally diagnosed.

There’s also a lack of awareness among the general public. Many don’t see headache disorders as a serious issue. This is because they are episodic, don’t cause death, and aren’t contagious. Governments also don’t acknowledge the burden of headaches on society, the WHO said, as they don’t recognize that the costs of treating headaches are smaller compared to the savings that can be made.

“We are not certain we can reduce the prevalence so much, but we know that those who have headaches or migraine can get fewer attacks by improved diagnosis, prevention, and treatment. Education of health personnel, as well as patients and the general public, is important,” Stovner told ZME Science. “We have many projects, most of them on better treatment of difficult headaches.”

The study was published in the Journal of Headache and Pain.