Background

Recurrent headache disorders, such as migraine, are common medical problems, ranking among the top causes of suffering and disability in the United States and worldwide. Compared with many other chronic diseases, the morbidity associated with these headache disorders mostly affects young and middle-aged adults who are otherwise healthy. In this targeted systematic review, Burch and colleagues used population-based US government surveys to provide updated estimates on the prevalence and sex distribution of migraine and severe headache in adults.¹

Study Design

The investigators examined data from the most up-to-date population-based health surveillance studies from the National Health Interview Survey (NHIS), the National Hospital Ambulatory Medical Care Survey (NHAMCS), and the National Ambulatory Medical Care Survey (NAMCS). Burch and colleagues summarized the data from each of these 3 sources over time and across demographic variables.¹

For the NHIS, trained government interviewers collect data by conducting computer-assisted personal interviews of individuals in households across the United States. The survey includes questions about health care use and sociodemographic characteristics. Specifically, patients were asked whether they had experienced severe headache or migraine during the past 3 months.¹ The NHAMCS collects data on the use of ambulatory care services provided in US hospitals and other medical care facilities in all states and the District of Columbia. Representatives train medical staff in how to appropriately collect data and complete patient record forms for a random sample of patient visits over a 4-week period. Data collected included information about patients’ self-reported reason for visit; physicians’ diagnoses, tests, procedures, and medications; and patients’ demographic characteristics. NAMCS is an annual survey of care provided at physicians’ offices. These representatives train physicians in proper data collection, using special forms to provide information about a random 1-week reporting period. Data collected from each visit during the selected week include information about patients’ primary reason for visit and symptoms, physicians’ diagnoses, prescribed medications, and other treatments.¹

Results

NHIS data from 1997 to 2015 were used, and the investigators used this information to discuss the prevalence of migraine or severe headache in adults, including for specific racial and ethnic groups. In particular, in 2014, the NHIS conducted a specific Native Hawaiian and Pacific Islanders survey, collecting information from 3197 Native Hawaiian and Pacific Islander households and 11,085 persons.¹

The Table summarizes select data from the 2015 survey, which contained information for 33,672 adults 18 years or older from 32 states and the District of Columbia. These data demonstrate a high overall prevalence of self-reported migraine or severe headache, affecting approximately 1 in 6 American adults (15.3%; 95% CI, 14.75%-15.85%). Prevalence was higher in women (20.7%; 95% CI, 19.84%-21.56%) than in men (9.7%; 95% CI, 9.05%-10.35%).¹

The investigators also found a higher burden of migraine among people aged 18 to 44 years (17.9%), unemployed individuals who had previously worked (21.4%) or had never worked (16.6%), people with less than $35,000 annual family income (19.9%), and those over 65 years on Medicare and Medicaid (16.4%).¹

Among specific racial and ethnic groups, the prevalence of migraine or severe headache in 2015 was highest in American Indians or Alaska Natives (18.4%) and lowest in Asians (11.3%). The prevalence was 13.2% among Native Hawaiian or Pacific Islanders. ¹

For the NHAMCS, Burch and colleagues evaluated data from the 2010 through 2014 surveys. The most updated information was from 2014, comprising data from December 2013 to December 2014 for 283 hospitals with emergency departments (EDs) and providing 23,844 patient record forms. Using these data, the investigators showed that headache remains one of the most common reasons for an ED visit, consistently ranking as the fourth or fifth leading cause for such visits, accounting for about 3% of all visits annually. In 2014, this translated to approximately 4 million ED visits.¹

Headache is especially burdensome for women of reproductive age. More than half of all ED visits for headache involved women in this group. It was the third most common reason for ED visits for women aged 15 to 64 years, accounting for 2.7% of such visits in this group.¹

Indeed, headache remains a common reason for ED visits among individuals in all segments of the US population, except for older men. It was the sixth most common cause of ED visits among men aged 15 to 64 years, accounting for 1.0% of such visits in this group.¹

The most recent data for the NAMCS were from 2014, for which 2179 physicians completed patient record forms and 1822 participated fully or adequately. However, according to the investigators, the NAMCS contains no new information since the last assessment of government sources of data. Although the 2009-2010 NAMCS lists “headache/pain in the head” as the 20th most common patient-reported reason for outpatient visits, it has not ranked among the top 20 reasons for outpatient visits since then.¹

Conclusion

Reference

The findings of this targeted systematic review provide updated information about the prevalence of migraine and severe headache in the United States, highlighting their largely stable prevalence over the last 19 years. These disorders not only remain an important public health problem, but also continue to disproportionately affect women, as well as other disadvantaged segments of the US population. Understanding how migraine and severe headache affect these specific patient populations is key to improving clinicians’ ability to ensure that high-need patients can access effective treatments for these disorders.¹

1. Burch R, Rizzoli P, Loder E. The prevalence and impact of migraine and severe headache in the United States: figures and trends from government health studies. Headache. 2018;58(4):496-505. doi: 10.1111/head.13281.