The Relationship Between Migraine or Severe Headache and Chronic Health Conditions: A Cross-Sectional Study from the National Health Interview Survey 2013–2015

Abstract

Objective

To estimate the prevalence of having at least one or two or more chronic health conditions among US adults with self-reported migraine or severe headaches.

Design

Cross-sectional study.

Methods

Using data collected from the 2013–2015 National Health Interview Survey, we examined adults with and without migraine or severe headache and associations with chronic obstructive pulmonary disease, cancer, heart disease, stroke, diabetes, and hypertension. We calculated point estimates, variances, and 95% confidence intervals and conducted bivariate and multivariable logistic regression modeling to examine the relationships between migraine or severe headache and each of the chronic health conditions, as well as multinomial modeling, to examine the relationship between migraine or severe headache and having one or more chronic health conditions.

Results

A total of 104,926 people were in the study. Adults aged 18 to 44 years (18.2%), women (20.1%), and those with some college education (17.6%) had the greatest proportion with migraine or severe headache (P < 0.0001). Using multinomial modeling with the number of chronic health conditions as the dependent variable, adults reporting migraine had an increased odds of reporting a single chronic health condition (adjusted odds ratio [aOR] = 1.7, 95% confidence interval [CI] = 1.6–1.8) and more than double the odds of reporting two or more chronic health conditions (aOR = 2.5, 95% CI = 2.3–2.8) compared with adults who did not have migraine or severe headache.

Conclusions

Our study confirms observed relationships between migraine or severe headache and chronic health conditions and supports the need for further research to uncover the shared biological pathways.

Introduction

Migraine is a common chronic health condition with a global age-standardized prevalence of 14.4%. Migraine is also the second most disabling condition, per the World Health Organization (WHO), in disability-adjusted life-years [1]. As such, migraine has serious economic and medical consequences, with direct costs of treatment and indirect costs related to disability and lost productivity. In 2010, the annual cost of migraine-related health care treatment was $3.2 billion for outpatient visits, $700 million for emergency department visits, and $375 million for inpatient hospitalizations [2]. Neurologists and headache specialists consider headache medicine to be a complex cognitive specialty requiring time-intensive evaluations to treat patients with migraine or severe headache [3].

Along with the costs of treatment and disability, migraine is associated with both medical and psychiatric comorbidities, which adds to the burden of migraine on individuals and society [4,5]. Some of these comorbidities are also chronic health conditions, which over time can become especially burdensome for the migraine patient population. Nearly half (49.8%) of the US adult population between the ages of 18 and 65 have at least one of the major risk factors for chronic health conditions such as heart disease, stroke, uncontrolled hypertension, and high low-density lipoprotein cholesterol [6]. Multiple studies have shown that people with migraine are at higher risk of heart disease and stroke compared with the general population [7,8]. The purpose of this study was to estimate the prevalence of having at least one or two or more chronic health conditions (MCCs) among the US adult population with self-reported migraine or severe headaches. This was a cross-sectional study to assess associations between migraine or severe headache and chronic health conditions prevalent in the US population. As such, we did not examine temporal relationships between disorders.

Our study examined the prevalence and the association between migraine or severe headache and stroke, heart disease, hypertension, diabetes, chronic obstructive pulmonary disease (COPD), and cancer. We hypothesized that there is a positive association between having at least one or two or more of these chronic health conditions among adults who self-report migraine or severe headache compared with adults who do not self-report having migraine or severe headache.

Methods

Data Source

We examined data collected from adults aged 18 years and older who participated in the National Health Interview Survey (NHIS) from 2013 to 2015 [9]. The NHIS is a cross-sectional household interview survey. Sampling and interviewing for the NHIS are usually conducted in person at the participant’s home and are continuous throughout the year. NHIS is designed to yield estimates representative of the civilian noninstitutionalized population of the United States, and this analysis used sample weights to produce national estimates. Data weighting procedures are described in more detail elsewhere [10]. We selected the 2013–2015 survey years to provide a current update of the associations with migraine or severe headache, as these years included consistently defined variables. We did not conduct a prestudy power analysis because we were using several years of the largest national data set dedicated to health. Also, prior studies of migraine or severe headache have demonstrated that the NHIS survey is sufficiently large to detect the associations between migraine or severe headache and multiple comorbid chronic health conditions in this study [11–14]. As this study used data from a publicly available national data set, use of its data is exempt from institutional review board approval. All participants provided consent.

Migraine or Severe Headache and Chronic Health Conditions

The NHIS survey asks participants whether they have had a severe headache or migraine during the past three months. The NHIS data set has previously been used in other migraine studies to assess migraine burden and health care utilization [15,16]. The chronic health conditions included in this study originated from the 10 physical conditions from a list of 20 identified by the US Department of Health and Human Services (HHS) as conditions to be used when measuring the occurrence of chronic conditions in the United States [6,17]. This was ascertained as follows:

• COPD was based on positive responses to questions about having ever been told by a health professional that they had emphysema or having been told in the past 12 months that they had chronic bronchitis.

• Respondents were asked whether they had ever been told by a health professional that they had coronary heart disease, angina (angina pectoris), a heart attack (myocardial infarction), or any other kind of heart disease or heart condition, diabetes, or stroke.

• Hypertension was based on the respondent having an elevated blood pressure on two or more different doctor visits, or being told by a doctor that you have hypertension or high blood pressure.

• The presence of cancer was based on the respondent reporting having ever been told by a health professional that they had a malignancy (excluding nonmelanoma skin cancer) [17].

Relatively small numbers of respondents were missing chronic health condition data: migraine or severe headache (N = 58), heart disease (N = 33), hypertension (N = 127), diabetes (N = 43), cancer (excluding nonmelanoma neoplasms) (N = 1,838), COPD (N = 33), and stroke (N = 24). Respondents who did not answer a question, resulting in a lack of data for that respondent for a variable used in the regressions, were not included in the multivariable analyses, but these respondents were retained in the overall study population.

Demographic Characteristics

Race/ethnicity was categorized as Hispanic, non-Hispanic white, non-Hispanic black, and other race/ethnicity. Age groups included 18–44 years, 45–64 years, and 65 years and over. We determined our age categories based on well-defined age groupings using the NHIS collected survey data [18].

Annual family income was categorized into a poverty index ratio (PIR) of below 100% of the federal poverty level (FPL), 100–199% of the FPL, 200–399% of the FPL, and 400% or more of the FPL [19]. Percentage of poverty level was based on reported and imputed family income, family size, the number of children in the family, and the age of the family’s adults [20]. NHIS multiple imputation files were used to assign an income level for those missing data [20]. Education was not included in final models because it was correlated with PIR (correlation coefficient = 0.31, P < 0.0001), and PIR is a known measure of socioeconomic status.

Statistical Analysis

Point estimates, variances, and 95% confidence intervals (CIs) were calculated using SUDAAN (release 10.0) [21]. Categorical variables were evaluated using Rao Scott chi-square statistics for weighted survey data with an alpha (α) level of 0.05 (two-sided) to indicate significance. A priori, we decided to stratify our analyses by age because migraine is most common during the working years [22], whereas chronic health conditions are more likely to occur in advancing age [23]. We report all percentages and odds ratios as a measure of variance.

Multivariable logistic regression models (Table 1) examined associations between migraine or severe headache as an independent variable and the chronic health conditions as dependent variables in separate models for each, adjusting for sociodemographic characteristics including age group, gender, race/ethnicity, PIR, and survey year. We chose to use migraine or severe headache as an independent variable in the models predicting chronic health conditions because migraine may precede the development of a chronic health condition.

Table 1.

Multivariable models with chronic health conditions as the dependent variable and migraine or severe headache and sociodemographic characteristics as the independent variables, NHIS: 2013–2015

Independent Variables†	Chronic Pulmonary Obstructive Disease, aOR (95% CI)	Cancer, aOR (95% CI)	Heart Disease, aOR (95% CI)	Stroke, aOR (95% CI)	Diabetes, aOR (95% CI)	Hypertension, aOR (95% CI)
Migraine or severe headache	2.8 (2.6–3.1)**	1.4 (1.3–1.5)**	2.0 (1.9–2.2)**	2.1 (1.9–2.4)**	1.2 (1.1–1.3)**	1.6 (1.5–1.7)**
Sex
Female	1.2 (1.1–1.3)**	1.2 (1.1–1.3)**	00.69 (0.65–0.73)**	0.79 (0.72–0.87)**	0.80 (0.76–0.85)**	0.82 (0.79–0.86)**
Male	Reference	Reference	Reference	Reference	Reference	Reference
Race/ethnicity
Hispanic	0.42 (0.37–0.47)**	0.53 (0.47–0.60)**	0.54 (0.49–0.60)**	0.79 (0.72–0.87)**	1.4 (1.3–1.6)**	0.81 (0.76–0.86)**
Non-Hispanic white	Reference	Reference	Reference	Reference	Reference	Reference
Non-Hispanic black	0.78 (0.70–0.87)**	0.65 (0.58–0.74)**	0.76 (0.70–0.83)**	1.3 (1.1–1.4)**	1.6 (1.5–1.8)**	1.7 (1.6–1.8)**
Other race/ethnicities	0.33 (0.26–0.43)**	0.36 (0.29–0.44)**	0.49 (0.42–0.56)**	0.59 (0.45–0.79)**	1.0 (0.96–1.2)	0.79 (0.72–0.86)**
Age group
18–44 y	Reference	Reference	Reference	Reference	Reference	Reference
45–64 y	2.7 (2.4–3.0)**	4.2 (3.8–4.7)**	3.3 (3.0–3.6)**	6.5 (5.2–8.0)**	6.7 (6.1–7.3)**	5.8 (5.5–6.1)**
≥65 y	4.1 (3.6–4.6)**	13.4 (12.0–15.0)***	10.6 (9.8–11.5)**	19.9 (16.6–23.9)**	13.1 (12.0–14.4)**	15.5 (14.7–16.4)**
Poverty index ratio
<100% of the FPL	1.8 (1.6–2.0)**	1.0 (0.93–1.1)	1.4 (1.3–1.6)**	1.8 (1.–2.1)**	1.4 (1.2–1.5)**	1.2 (1.2–1.3)*
100–199% of the FPL	1.5 (1.3–1.6)**	0.97 (0.87–1.0)	1.2 (1.1–1.3)**	1.4 (1.2–1.6)**	1.2 (1.1–1.3)**	1.1 (1.0–1.2)**
200–399% of the FPL	Reference	Reference	Reference	Reference	Reference	Reference
≥400% of the FPL	0.59 (0.53–0.66)**	0.96 (0.87–1.0)	0.79 (0.74–0.86)**	0.52 (0.44–0.60)**	0.68 (0.62–0.74)**	0.82 (0.78–0.87)**
Survey year‡	1.0 (0.96–1.0)	1.0 (0.97–1.0)	1.0 (0.99–1.0)	1.0 (0.94–1.0)	1.0 (0.98–1.0)	1.0 (1.0–1.0)*

^aOR = adjusted odds ratio; CI = confidence interval; FPL = federal poverty level; NHIS = National Health Interview Survey.

^* P ≤ 0.05; **P < 0.01; ***P < 0.001.

^†Independent variables included migraine or severe headache, gender, race/ethnicity, age group, poverty index ratio, and survey year. The reference level for migraine or severe headache was its absence.

^‡The reference level for survey year was 2013. All survey years were not reported. Reference level for the chronic health conditions was their absence.

We examined the proportion with migraine or severe headache by the chronic health conditions and sociodemographic variables. We included each sociodemographic variable in our multivariable logistic models as independent variables (Table 1), as we found a statistically significant relationship for each of the variables and migraine or severe headache at the bivariate level of analysis, with one exception; we did not include education in the separate multivariable logistic regression models. Education and income were statistically associated, and low income has been shown to be an indicator of disease progression [24]. We also examined in a multinomial model the relationship between migraine or severe headache and having one or more chronic health conditions. Because the dependent variable included more than one level (number of conditions could equal 0, 1, or ≥2), we used a multinomial model that could assess the odds of migraine or severe headache based on these three categories of outcomes.

Results

The analytic sample included 104,843 adults representing 239,660,029 nation-wide. In this sample, 15,853 adults (15.1%) reported having had a migraine or severe headache in the last three months. The analytic sample was 51.8% female. In the analytic sample, 46.9% were between age 18 and 44 years, 34.5% were between 45 and 64 years, and 18.5% were 65 years and over (sample mean age [SD] = 47.0 [17.8] years). The percentage reporting migraine or severe headache was highest among females (20.1%), non-Hispanic blacks (16.4%), those between age 18 and 44 years (17.6%), and those having some college education (17.6%, P < 0.0001). The greatest proportion of adults reporting migraine or severe headache was in the lowest income group (23.0%).

There was a greater proportion of adults with chronic health conditions who also had reported migraine or severe headache and were aged 65 years and older. In adults aged 65 years and over who did not report migraine or severe headache, there was a greater proportion reporting one chronic health condition compared with adults in the same age group who reported migraine or severe headache (33.0% vs 30.9%). Among adults aged 18–44 and 45–64 reporting migraine or severe headache, there was a greater proportion with two or more chronic health conditions, compared with adults in the same age group who did not report migraine or severe headache (P < 0.0001 for both age groups with number of chronic conditions reported in those adults with migraine or severe headache vs those adults without migraine or severe headache). A greater proportion of adults aged 65 years and over who had migraine or severe headache reported two or more chronic health conditions, compared with adults in the same age group who did not report migraine or severe headache (50.8% vs 41.1%). There was a statistically significant difference in the number of chronic health conditions by migraine or severe headache status across all age groups (P < 0.0001).

The preliminary bivariate analysis demonstrated a relationship between migraine or severe headache and each of the chronic health conditions, with the exception of cancer and diabetes. However, in the separate final models included in the covariates, all of the chronic health conditions had a significant association with migraine and severe headache, as follows: COPD: adjusted odds ratio (aOR) = 2.4, 95% confidence interval (CI) = 2.2–2.6; cancer: aOR = 1.1, 95% CI = 1.0–1.3; heart disease: aOR = 1.6, 95% CI = 1.5–1.8; diabetes: aOR = 1.4, 95% CI = 1.3–1.5.

In separate multivariable models predicting each chronic health condition, adjusted for sex, race/ethnicity, age group, PIR, and survey year, there was over a twofold increased association between migraine or severe headache and COPD, heart disease, and stroke compared with no migraine or severe headache (COPD: aOR = 2.8, 95% CI = 2.6–3.1; heart disease: aOR = 2.0, 95% CI = 1.9–2.2; stroke: aOR = 2.1, 95% CI-1.9-2.4) (Table 1). There was a statistically significant association in separate models between migraine or severe headache, diabetes (aOR = 1.2, 95% CI = 1.1–1.3), cancer (aOR = 1.4, 95% CI = 1.3–1.5), and hypertension (aOR = 1.6, 95% CI = 1.5–1.7) (Table 1). The association with migraine or severe headache was stronger for women with COPD and cancer compared with men (Table 1). Compared with non-Hispanic whites, non-Hispanic blacks, Hispanics, and other race/ethnicity, there was a decreased association of migraine or severe headache with COPD, cancer, and heart disease (Table 1). However, in non-Hispanic blacks compared with non-Hispanic whites, there was an increased association of migraine or severe headache with stroke, diabetes, and hypertension (Table 1).

Migraine or severe headache was also found to be statistically significantly associated with the number of chronic health conditions. In a multinomial model adjusted for sex, race/ethnicity, age group, income, and survey year, with chronic health conditions as the dependent variable, adults reporting migraine or severe headache had an increased odds of reporting a single chronic health condition (aOR = 1.7, 95% CI = 1.6–1.8) and more than double the odds of reporting two or more chronic health conditions (aOR = 2.5, 95% CI = 2.3–2.8) compared with adults who did not have migraine or severe headache.

Discussion

Based on 2013–2015 NHIS data, we had two major findings: 1) migraine or severe headache is comorbid with stroke, heart disease, hypertension, and COPD. We found an increased odds of diabetes, cancer, and migraine or severe headache in separate models; however, it did not appear in the unadjusted models and therefore requires further examination. Our results corroborate previous results demonstrating that migraine is associated with increased prevalence of lifestyle-related disorders, in addition to conditions with genetic and environmental underpinnings. 2) Younger adults with migraine or severe headache are more likely to report at least one of these chronic health conditions or two or more of these chronic health conditions compared with younger adults who did not self-report migraine or severe headache.

Multiple Chronic Health Conditions

The relationship of migraine to MCCs is uncertain, but likely multifactorial. In some cases, the relationship may be causal, meaning migraine leads to the comorbid condition or vice versa. For example, inflammation and hypercoagulability related to migraine-induced activation of the endothelium [25] heighten the odds of cardiac and brain ischemia directly or via atherosclerosis [26,27], although the evidence for a link between migraine and atherosclerosis is conflicting [28,29]. Insulin resistance, which has been independently linked to migraine [30] and chronic migraine [31], is associated with hematologic, metabolic, and cellular derangements that induce coagulation and atherosclerosis, thus increasing the odds of stroke and coronary artery disease [32]. Alternative explanations for the association of migraine and multiple chronic health conditions include that of a shared pathogenesis related to common genes, common environmental influences, or to the interaction of genes and environment. For example, a number of the genetic polymorphisms related to monogenic migraine syndromes or to common polygenic migraine involve vascular pathways [33]. Adverse childhood experiences are examples of environmental factors that are associated with migraine in adults [34], as well as with multiple migraine comorbidities [35].

Stroke

We found that adults with migraine or severe headache have higher odds of stroke, in keeping with findings from multiple large epidemiologic studies worldwide showing that migraine, and particularly migraine with aura, is associated with increased odds of stroke [36]. Migraine and stroke have been linked through a variety of mechanisms, involving the vasculature (vasospasm [37], arterial dissection [38], venous thrombosis [39]), the heart (patent foramen ovale [40]), and the blood (hypercoagulability [25]). Intriguingly, in a 12-year follow-up of the Women’s Health Study, a prospective cohort study of >27,000 US women, enrolled at age >45 years, the association between migraine with aura and ischemic stroke was apparent only among women in the lowest Framingham risk score group, including with low rather elevated blood pressure [41]. This suggests that atherosclerotic vascular changes do not play a role in the migraine–stroke relationship, despite evidence of endothelial perturbation.

Another mechanism linking migraine and stroke is the phenomenon of cortical spreading depression (CSD), believed to be the physiological correlate of aura. In response to CSD-induced changes in neuronal and glial metabolism, there is a brief spreading hyperemia followed by oligemia corresponding to a 20–30% reduction in cerebral blood flow. This is generally considered to be well above the ischemic threshold for stroke [42,43]. Alternatively, ischemia, from any source, may induce CSD, so that aura can in some cases represent a transient ischemic attack (TIA) equivalent. The relationship between IR, hypertension, and stroke may be enhanced in the presence of oral contraceptive and cigarette use [8,31,32].

Heart Disease

We found an association between migraine or severe headache and heart disease. In the epidemiological cross-sectional GEM study of 5,755 persons age 20–65 years examining migraine and cardiovascular disease risk factors, individuals with migraine with aura had a higher cardiovascular risk profile than those without migraine, including higher cholesterol, elevated blood pressure, and a reported history of early-onset cardiovascular disease and stroke [7]. In the Women’s Health Study, described above, migraine with aura was associated with increased risk of angina for women with low and high Framingham risk score groups, but the association with myocardial infarctions was only in those with a high Framingham risk score [41]. The researchers hypothesized that migraine with aura may lead to angina in coronary arteries not altered by atherosclerosis through one mechanism, and through another mechanism lead to angina and myocardial infarction in vasculature impaired by atherosclerosis. Among the mechanisms considered are those related to increases in pro-thrombotic or vasoactive factors, both components of endothelial dysfunction [27,36]. Recently, endothelial microparticles, which are released as a consequence of vascular reactivity, and in turn bind to and damage the endothelium, have been found in association with migraine with aura (MA) in young women [44]. The authors also found that the MA subgroup had reduced levels of stromal cell–derived factor 1 alpha, which is essential for maintenance of endothelial integrity [45]. In another study, findings of lower numbers of circulating endothelial progenitor cells (EPCs) [46] in people with migraine have been interpreted as reflecting a heightened degree of endothelial repair.

Hypertension

Our study results support the findings of the cross-sectional GEM study and of a multicenter clinic-based Italian survey of 2,973 patients indicating that migraine or severe headache is associated with higher rates of hypertension [7,47]. Possible explanations may be endothelial dysfunction, deficiency of autonomic cardiovascular regulation, and association with the renin angiotensin system [48].

Diabetes

We found that, in general, people with migraine or severe headache are also more likely to have diabetes compared with adults who do not report migraine or severe headache. There have been several studies assessing the relationship between diabetes mellitus (DM) and migraine. Some prior studies indicate an inverse relationship between DM 1 and migraine [49,50], whereas other studies show no association between migraine and DM1 [49,50]. The Nord-Trondelag Health Study, a large cross-sectional population-based study, showed an inverse relationship between migraine and DM 1. In that study, 26,121 participants with a median age of 54.1 years were examined, and 81 of the participants had DM 1. These individuals showed a lower prevalence of migraine compared with those without DM 1 [49].

With regards to DM 2, results from the Women’s Health Study showed no statistically significant association with migraine [51]. However, other studies have shown DM 2 associated either with a lower prevalence of migraine compared with those without DM 2 [52] or with a higher prevalence of migraine [53]. Studies suggest that the blood glucose level itself and/or low insulin activation and insulin resistance may be associated with migraine, but there is not a clear mechanism for the association [54,55]. In our results, we found an association between diabetes and migraine; however, our study did not differ between the two types of diabetes.

COPD

We found a statistically significant association between migraine or severe headache and COPD. The association between COPD and migraine or severe headache may be because of headache-related sleep disturbances [56]. In a clinic-based study conducted with 119 COPD patients, 31.9% of patients reported chronic headache symptoms, and just over half of these also had sleep disorders. It was hypothesized that these headaches occur because of the chronic hypercapnia caused by COPD. In addition, the headaches related to COPD may be attributed to airway constriction [56]. Among community-based studies, one in China with 1,143 participants showed an association of migraine and COPD [57], and the US-based American Migraine Prevalence and Prevention study with 11,904 persons with migraine showed an association of chronic (vs episodic) migraine with COPD [58].

Cancer

We found a marginal association between migraine or severe headache and cancer (Appendix Table 3). Both chronic health conditions have been associated with inflammation [59,60], and this may serve as a possible link between them. Previous studies have shown a negative association between migraine and breast cancer; one study found that migraine patients have a 26% reduced risk of breast cancer [61]. One possible explanation for this decreased risk of breast cancer is that the frequent use of nonsteroidal anti-inflammatory drugs (NSAIDs) among people with migraine provides a protective effect [61]. Another possible explanation is that migraines can be triggered or suppressed by hormone levels and breast cancer is a hormonally related disease [61]. Other types of cancer have not been studied with migraine as closely as breast cancer.

As stated above, there was a greater proportion of adults aged 65 years and over who did not have migraine or severe headache with at least one chronic health condition. There are a few possible explanations, as follows: 1) Adults with migraine or severe headache have multiple chronic health conditions and become unable to care for themselves and end up in facilities where the NHIS is not sampled. 2) There may be differences in survival in younger adults with migraine or severe headache and chronic health conditions, compared with younger adults without migraine or severe headache but who also have chronic health conditions. 3) Older individuals are more likely to have two or more chronic health conditions. All of these explanations warrant further investigation.

The strength of this study is that we used the largest data set from an adult noninstitutionalized civilian population, which spans all ages and includes information on a wide variety of chronic health conditions and SES variables. This increases the generalizability of our results. Important to our findings is that we confirmed the need for health care providers to consider all the chronic health conditions for which an adult with migraine or severe headache is at risk. Although the prevalence of chronic health conditions is still relatively rare among young adults with migraine or severe headaches, our findings underscore the need for health care providers to assess risk for chronic health conditions such as stroke.

This study has several limitations: 1) The determination of migraine or severe headache in the NHIS survey was made by asking participants whether they had experienced migraine or severe headache in the past three months. Thus, those with infrequent episodic migraine may have been included in the no migraine group. The determination of migraine or severe headache was by self-report and did not use the International Classification of Headache Disorder criteria. 2) Our results are likely conservative estimates of the number of chronic health conditions of migraine or severe headache because we limited our study to the top six chronic health conditions. 3) The temporal relationship of the onset of migraine or severe headache and of the chronic health conditions was not assessed. 4) Our study does not include mental chronic health conditions, which are highly comorbid with migraine [4]. 5) Survey data did not distinguish between DM1 and DM2, nor did they distinguish between types of cancer. 6) The NIHS sample is from the noninstitutionalized civilian population. Thus, our study excludes people in long-term care or other congregant settings, who may have more chronic health conditions. However, given that migraine decreases with age, we believe that the sample is still adequate [6]. 7) Survey data are cross-sectional, and therefore causation cannot be determined.

Conclusions

As this population-based study and other studies have found, chronic health conditions, particularly COPD, heart disease, cancer, diabetes, and stroke, co-occur in adults with migraine or severe headache. More research is necessary to explain the biological underpinnings of these associations and identify the shared pathways.