Headache disability in orofacial pain patients

A female-specific role for trigeminal dynorphin in orofacial pain comorbidity

ABSTRACT

Migraine is commonly reported in patients with temporomandibular disorders (TMDs), but little is known about the mechanisms underlying the comorbid condition. Here, we prepared a mouse model to investigate this comorbidity, in which masseter muscle tendon ligation (MMTL) was performed to induce a myogenic TMD, and the pre-existing TMD enabled a subthreshold dose of nitroglycerin (NTG) to produce migraine-like pain in mice. RNA sequencing followed by real-time quantitative polymerase chain reaction confirmation showed that MMTL plus NTG treatment increased prodynorphin ( Pdyn ) mRNA expression in the spinal trigeminal nucleus caudalis (Sp5C) of female mice but not in male mice. Chemogenetic inhibition of Pdyn -expressing neurons or microinjection of antidynorphin antiserum in the Sp5C alleviated MMTL-induced masseter hypersensitivity and diminished the MMTL-enabled migraine-like pain in female mice but not in male mice. Moreover, chemogenetic activation of Pdyn -expressing neurons or microinjection of dynorphin A (1-17) peptide in the Sp5C enabled a subthreshold dose of NTG to induce migraine-like pain in female mice but not in male mice. Taken together, our results suggest that trigeminal dynorphin has a female-specific role in the modulation of comorbid TMDs and migraine.

Temporomandibular treatments are significantly efficient in improving otologic symptoms

Symptoms of temporomandibular disorders (TMD) could be present as otologic symptoms like earache and dizziness in some patients. In most cases, these symptoms are not recognized because otolaryngologists fail to diagnose TMD as a source of the problem. This investigation was conducted to evaluate the effect of TMD treatments on the otologic symptoms which after taking history and clinical examinations seemed to be related to TMD. In the present study, the patients who were complaining of otalgia, ear fullness, tinnitus, hearing loss, and dizziness were evaluated by an ear fellow. Forty patients who had no known otologic or other primary causes to explain their symptoms, were referred to the orofacial pain clinic with the possible diagnosis of TMD. If the diagnosis was confirmed by an orofacial pain specialist, a combination of TMD treatments was administered to each case and the patients were followed up. The results showed that following implementation of treatment protocols for TMD, more than 50% of the patients reported complete or partial recovery in the second follow-up (p < 0.05). The most common otologic symptom of the referred cases was earache, and the most common associated complaint was neck pain. All the patients had one or more parafunctional habits. This study showed that TMD treatments were significantly efficient in improving otologic symptoms partially or completely and the authors concluded that for the patients with otolaryngologic unexplained symptoms, an overhaul examination is needed to assess TMD as a possible cause of the patient complaint. It is recommended that in cases with unexplained otologic symptoms, otolaryngologists care more about the neck trigger points (TP) and ask about the patient's parafunctional habits. Otolaryngologists and dentists need to be aware of the risk of developing otologic symptoms caused by these habits or cervical TPs.

Pathogenesis and Differential Diagnosis of Temporomandibular Joint Disorders

Temporomandibular disorders (TMDs) are an umbrella term including disorders of the temporomandibular joint and muscles of the masticatory system. They are the most common nonodontogenic cause of pain in the orofacial region. A clear understanding of various conditions, underlying mechanisms, clinical presentation, and examination skills is required to effectively diagnose and manage these patients.

Clinical, psychological, and sensory characteristics associated with headache attributed to temporomandibular disorder in people with chronic myogenous temporomandibular disorder and primary headaches

Background

Headache attributed to Temporomandibular Disorder (HATMD) is a secondary headache that may have features resulting in diagnostic overlap with primary headaches, namely, tension-type (TTH) or migraine. This cross-sectional study of people with both chronic myogenous TMD and primary headaches evaluated characteristics associated with HATMD.

Methods

From a clinical trial of adults, baseline data were used from a subset with diagnoses of both TMD myalgia according to the Diagnostic Criteria for TMD (DC/TMD) and TTH or migraine according to the International Classification of Headache Disorders, 3rd edition. HATMD was classified based on the DC/TMD. Questionnaires and examinations evaluated 42 characteristics of facial pain, headache, general health, psychological distress, and experimental pain sensitivity. Univariate regression models quantified the associations of each characteristic with HATMD (present versus absent), headache type (TTH versus migraine), and their interaction in a factorial design. Multivariable lasso regression identified the most important predictors of HATMD.

Results

Of 185 participants, 114 (61.6%) had HATMD, while the numbers with TTH (n = 98, 53.0%) and migraine (n = 87, 47.0%) were similar. HATMD was more likely among migraineurs (61/87 = 70.1%) than participants with TTH (53/98 = 54.1%; odds ratio = 2.0; 95%CL = 1.1, 3.7). In univariate analyses, characteristics associated with HATMD included pain-free jaw opening and examination-evoked pain in masticatory muscles and temporomandibular joints (TMJ) as well as frequency and impact of headache, but not frequency or impact of facial pain. Lowered blood pressure but not psychological or sensory characteristics was associated with HATMD. Multiple characteristics of facial pain, headache, general health, and psychological distress differed between TTH or migraine groups. Few interactions were observed, demonstrating that most characteristics’ associations with HATMD were consistent in TTH and migraine groups. The lasso model identified headache frequency and examination-evoked muscle pain as the most important predictors of HATMD.

Conclusions

HATMD is highly prevalent among patients with chronic myogenous TMD and headaches and often presents as migraine. In contrast to primary headaches, HATMD is associated with higher headache frequency and examination-evoked masticatory muscle pain, but with surprisingly few measures of facial pain, general health, and psychological distress. A better understanding of HATMD is necessary for developing targeted strategies for its management.

Trial identification and registration

SOPPRANO; NCT02437383. Registered May 7, 2015.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01255-1.

A Pre-Existing Myogenic Temporomandibular Disorder Increases Trigeminal Calcitonin Gene-Related Peptide and Enhances Nitroglycerin-Induced Hypersensitivity in Mice

Migraine is commonly reported among patients with temporomandibular disorders (TMDs), especially myogenic TMD. The pathophysiologic mechanisms related to the comorbidity of the two conditions remain elusive. In the present study, we combined masseter muscle tendon ligation (MMTL)-produced myogenic TMD with systemic injection of nitroglycerin (NTG)-induced migraine-like hypersensitivity in mice. Facial mechanical allodynia, functional allodynia, and light-aversive behavior were evaluated. Sumatriptan, an FDA-approved medication for migraine, was used to validate migraine-like hypersensitivity. Additionally, we examined the protein level of calcitonin gene-related peptide (CGRP) in the spinal trigeminal nucleus caudalis using immunohistochemistry. We observed that mice with MMTL pretreatment have a prolonged NTG-induced migraine-like hypersensitivity, and MMTL also enabled a non-sensitizing dose of NTG to trigger migraine-like hypersensitivity. Systemic injection of sumatriptan inhibited the MMTL-enhanced migraine-like hypersensitivity. MMTL pretreatment significantly upregulated the protein level of CGRP in the spinal trigeminal nucleus caudalis after NTG injection. Our results indicate that a pre-existing myogenic TMD can upregulate NTG-induced trigeminal CGRP and enhance migraine-like hypersensitivity.

Prevalence and correlations of temporomandibular disorders in Northern Jordan using diagnostic criteria axis I

AIM

The aim of the present study was to document the prevalence and possible correlations of temporomandibular disorders (TMD) in a sample of participants from Northern Jordan.

METHODS

A total of 368 adult participants were consecutively selected from visitors to a major health facility in Northern Jordan and examined according to the diagnostic criteria (DC) for TMD (DC/TMD) protocol. Patients with conditions that could interfere with TMD diagnosis were excluded. Pearson correlation and analysis of variance statistical tests were applied. Statistical significance was set at P ≤ 0.05, with a 95% confidence interval.

RESULTS

A total of 98 patients (26.7%) had 1 TMD diagnoses; 60 participants (16.3%) had a pain-related TMD diagnosis, 48 (13%) had intra-articular joint disorders (IAD), and 16 had both pain-related TMD and IAD. In addition, six (1.6%) participants were found to have degenerative joint disease. Females were found to have a higher prevalence of pain-related TMD diagnoses (r = 0.111, P = 0.034) and headache (r = 0.129, P = 0.013) than males. Clicking was positively related to both pain-related TMD (r = 0.154, P = 0.003) and IAD (r = 0.576, P = 0.000).

CONCLUSION

The frequency of TMD and related features was reported in a Northern Jordanian population using DC/TMD for the first time, and the results are comparable to other populations in similar study settings.

Temporal change in headache and its contribution to the risk of developing first-onset temporomandibular disorder in the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) study

While cross-sectional studies have demonstrated an association between headache and temporomandibular disorder (TMD), whether headache can predict the onset of TMD is unknown. The aims of this study were to evaluate the contribution of headache to the risk of developing TMD and describe patterns of change in headache types over time. An initially TMD-free cohort of 2410 persons with low frequency of headache completed quarterly questionnaires assessing TMD and headache symptoms over a median 3.0-year follow-up period. First-onset TMD was confirmed by clinical examination in 199 participants. Baseline reports of migraine (hazard ratio [HR] = 1.67, 95% confidence interval [CI]: 1.06-2.62) or mixed headache types (HR = 4.11, 95% CI: 1.47-11.46), or headache frequency (HR = 2.13, 95% CI: 1.31-3.48) predicted increased risk of developing TMD. In addition, headache dynamics across the follow-up period before the TMD onset were evaluated in a nested case-control study where 248 incident TMD cases were matched to 191 TMD-free controls. Both headache prevalence and frequency increased across the observation period among those who developed TMD but not among controls. Patients with TMD were more likely to experience worsening in the headache type compared with that by controls, eg, prevalence of definite migraine among TMD cases increased 10-fold. Among all headache types experienced by patients with TMD before the TMD onset, migraine had the highest odds of progression relative to remission (odds ratio = 2.8, 95% CI: 1.6-4.8), whereas for controls this ratio was significant only for the tension-type headache (odds ratio = 2.1, 95% CI: 1.2-3.9). The important clinical implication of these findings is that adequate treatment of migraine may reduce the risk for developing TMD.

Migraine With Isolated Facial Pain: A Diagnostic Challenge

We present a series of seven migraine patients with typical features of a migraine attack without aura, but atypical pain localization in the face in one or both of the lower two distributions of the trigeminal nerve (V2 and V3). All of them responded well to triptans. Three patients responded to preventive treatment for migraine with β-blockers ( n = 2) or valproic acid ( n = 1). These cases underline the heterogenic clinical presentation of migraine, which is sometimes difficult to diagnose even for headache specialists, and broaden the pathophysiological understanding of trigeminal nociceptive processing in migraine in the light of neuronal plasticity.

Headache-related disability among medical students in Amazon: a cross-sectional study

OBJECTIVE

To evaluate the prevalence of headache in medical students, and quantify the degree of disability through HIT-6 and MIDAS SCALE.

METHOD

The criteria established by International Headache Society were used and the HIT-6 and MIDAS, to asses disability.

RESULTS

140 medical students from UFAM were evaluated. 16.43% cases of migraine headache, 6.43% of probable migraine, and 23.57% of tension headaches were detected. 6.42% reported an absence of headache; and another 11.42% had secondary headache. According to the HIT-6 questionnaire, in 7.14% and 18.57% of the students, headaches were classified as having substantial to severe impact, respectively.

CONCLUSION

Migraine and probable migraine had higher scores than the other types of headache and, therefore, led to higher levels of disability. The present study did not find a significant correlation between student semester, age or extracurricular activities on the impact generated by headache.

Temporomandibular disorder is more prevalent among patients with primary headaches in a tertiary outpatient clinic

OBJECTIVE

The aim of this study was to estimate the prevalence of signs and symptoms of temporomandibular disorders (TMD) in patients with primary headaches attended in a tertiary neurology ambulatory.

METHOD

Authorized by the Ethics Committee, the present cross-sectional study was conducted with a random sample of patients screened for orofacial pain and primary headaches at a tertiary hospital in Northeast of Brazil.

RESULTS

The sample consisted in 42 patients with primary headache, 59.5% male. The prevalence of > 6 TMD signs and symptoms was 54.8%. In those patients with migraine TMD was present in 71.4% and in tension-type headache in 38.1% (p = 0.030; OR = 4.1). TMD was related to the clinical status of headache associated or attributed to medication overuse (p = 0.001).

CONCLUSION

TMD has a high prevalence in patients with primary headaches (54.8%). Special attention must be given to patients with migraine and headache associated or attributed to medication overuse.

Quality of life in primary headache disorders: A review

BACKGROUND

Health-related quality of life (HRQoL) is emerging as an important element of clinical research in primary headache disorders, allowing a measure of the impact of headache on patients' well-being and daily life. A better understanding of this may contribute to improved resource allocations and treatment approaches.

OBJECTIVE

The objective of this study is to review available data on HRQoL in primary headache disorders and identify any influencing factors.

METHODS

Database searches including MEDLINE, PsycINFO and EMBASE were performed. Studies that investigated HRQoL in patients with primary headache disorders were included and reviewed. Trials that evaluated the efficacy of medications or interventions were excluded.

RESULTS

A total of 80 articles were included in the review. Both physical and emotional/mental aspects of HRQoL were impaired across headache subtypes, although the extent varied depending on headache type. A number of factors influencing HRQoL were also identified.

CONCLUSION

This narrative review suggests that headache, particularly in its chronic form, has a great impact on HRQoL. Clinical practice should not solely focus on pain alleviation but rather adopt routine assessment of HRQoL. Furthermore, identification and management of associated psychological comorbidities, which can significantly influence HRQoL in headache sufferers, are essential for optimal clinical management.

Orofacial pain and headache: a review and look at the commonalities

Headache and facial pain - in particular, temporomandibular disorders (TMDs) - are very prevalent conditions in the general population. TMDs are defined as a collection of symptoms and signs involving masticatory muscles, the temporomandibular joints (TMJs), or both. The pain reported by TMD patients is typically located in the muscles of mastication, in the preauricular area, or in the TMJs. In many cases, headaches and facial pain will occur in the same patient. Much of the research relative to the relationship of these disorders focuses on statistics of association and prevalence data. This review will provide a brief description of the types and classifications of orofacial pains (OFPs), as well as point to relevant research describing the commonalities and potential comorbid nature of these maladies. Finally, several recent papers describing morphologic changes to the brain in headache and TMD individuals will be discussed in an effort to stimulate further research into the potential common pathophysiologic mechanism that may explain the comorbid nature of these disorders.

Psychological profile and self-administered relaxation in patients with craniofacial pain: a prospective in-office study

INTRODUCTION

The objective of this study was to evaluate the psychological profile of craniofacial pain sufferers and the impact of patient subtype classification on the short-time effectiveness of a self-administered relaxation training.

METHODS

One hundred unselected in-office patients (67% females) suffering from chronic facial pain and/or headache with the presumptive diagnose of temporo-mandibular disorder (TMD) completed a questionnaire battery comprising craniofacial pain perception, somatic complaints, irrational beliefs, and pain behavior and were classified into subtypes using cluster analysis. They underwent a self-administered progressive relaxation training and were re-evaluated for pain perception after 3 months.

RESULTS

Pain was mild to moderate in the majority of patients. Symptom domains comprised parafunctional activities, temporo-mandibular pain and dysfunction, fronto-temporal headache, head/neck and neck/back pain. Three patient subtypes were identified regarding symptom/dysfunction level: (i) low burden (mild/moderate), (ii) psychosocial dysfunction (moderate/high), (iii) adaptive coping (moderate/mild). Self-rated adherence to the recommended relaxation training was moderate throughout the sample, but self-rated relief was significantly different between clusters. At follow-up, pain intensity was significantly decreased in all patients, whereas pain-related interference was improved only in dysfunctional and adaptive patients. Improvement of symptom domains varied between clusters and was most comprehensive in adaptive patients.

CONCLUSIONS

In conclusion, craniofacial pain sufferers can be divided in meaningful subtypes based on their pain perception, irrational beliefs, and pain behaviour. A self-administered relaxation training generally yielded positive effects on pain perception, however the benefit may be greater in patients with more marked symptom impact (both dysfunctional and adaptive).

Temporomandibular disorders are differentially associated with headache diagnoses: a controlled study

OBJECTIVES

Temporomandibular disorders (TMDs) are considered to be comorbid with headaches. Earlier population studies have suggested that TMD may also be a risk factor for migraine progression. If that is true, TMD should be associated with specific headache syndromes (eg, migraine and chronic migraine), but not with headaches overall. Accordingly, our aim was to explore the relationship between TMD subtypes and severity with primary headaches in a controlled clinical study.

METHODS

The sample consisted of 300 individuals. TMDs were assessed using the Research Diagnostic Criteria for TMD, and primary headache was classified according to International Classification for Headache Disorders-2. Univariate and multivariate models assessed headache diagnoses and frequency as a function of the parameters of TMD.

RESULTS

Relative to those without TMD, individuals with myofascial TMD were significantly more likely to have chronic daily headaches (CDHs) [relative risk (RR)=7.8; 95% confidence interval (CI), 3.1-19.6], migraine (RR=4.4; 95% CI, 1.7-11.7), and episodic tension-type headache (RR=4.4; 95% CI, 1.5-12.6). Grade of TMD pain was associated with increased odds of CDH (P<0.0001), migraine (P<0.0001), and episodic tension-type headache (P<0.05). TMD severity was also associated with headache frequency. In multivariate analyses, TMD was associated with migraine and CDH (P=0.001). Painful TMD (P=0.0034) and grade of TMD pain (P<0.001) were associated with headache frequency.

DISCUSSION

TMD, TMD subtypes, and TMD severity are independently associated with specific headache syndromes and with headache frequency. This differential association suggests that the presence of central facilitation of nociceptive inputs may be of importance, as positive association was observed only when muscular TMD pain was involved.

Spinal trigeminal neurons demonstrate an increase in responses to dural electrical stimulation in the orofacial formalin test

Primary headaches are often associated with pain in the maxillofacial region commonly classified under the term “orofacial pain” (OFP). In turn, long-lasting OFP can trigger and perpetuate headache as an independent entity, which is able to persist after the resolution of the main disorder. A close association between OFP and headache complicates their cause and effect definition and leads to misdiagnosis. The precise mechanisms underlying this phenomenon are poorly understood, partly because of the deficiency of research-related findings. We combined the animal models of OFP and headache—the orofacial formalin test and the model of trigeminovascular nociception—to investigate the neurophysiological mechanisms underlying their comorbidity. In anesthetized rats, the ongoing activity of single convergent neurons in the spinal trigeminal nucleus was recorded in parallel to their responses to the electrical stimulation of the dura mater before and after the injection of formalin into their cutaneous receptive fields. Subcutaneous formalin resulted not only in the biphasic increase in the ongoing activity, but also in an enhancement of neuronal responses to dural electrical stimulation, which had similar time profile. These results demonstrated that under tonic pain in the orofacial region a nociceptive signaling from the dura mater to convergent trigeminal neurons is significantly enhanced apparently because of the development of central sensitization; this may contribute to the comorbidity of OFP and headache.

Prevalence and impact of headache in undergraduate students in Southern Brazil

OBJECTIVE

To determine the prevalence, characteristics and impact of headache among university students.

METHOD

The criteria established by the International Headache Society were used to define the primary headache subtypes and the Migraine Disability Assessment Questionnaire (MIDAS), to assess the disability. The students were then grouped into six categories: [1] migraine; [2] probable migraine; [3] tension-type headache; [4] probable tension-type headache; [5] non-classifiable headache; [6] no headache.

RESULTS

Of all undergraduate students interviewed, 74.5% had at least one headache episode in the last three months. Regarding disability, there was a significant difference between the headache types (p<0.0001). In the post-hoc analysis, migraine was the headache type with most reported disability.

CONCLUSION

Headache is a highly prevalent condition among the students at the University of Caxias do Sul. This disease may have a major impact on the students' lives and in some cases, ultimately lead to educational failure.

Estudo do impacto da enxaqueca na severidade da dor miofascial da musculatura mastigatória

OBJETIVO: comparar a severidade da dor subjetiva e objetiva, além de outras características associadas entre pacientes com dor miofascial com e sem o diagnóstico adicional de enxaqueca. MÉTODOS: foram selecionados 203 pacientes, com idade média de 40,3 anos (89,2% do sexo feminino), que se apresentaram à Clínica de Dor Orofacial da Universidade da Califórnia, Los Angeles, EUA - todos com diagnóstico primário de dor miofascial. Pacientes com diagnóstico secundário de enxaqueca foram incluídos (n=83) e formaram o grupo 2. O teste de Mann-Whitney foi utilizado para comparar o grupo 1 (dor miofascial) com o 2 (dor miofascial + enxaqueca) quanto à intensidade de dor à palpação e subjetiva, através de Escalas Analógicas Visuais (EAV). Também com o auxílio de EAV, foram comparados estado de humor, problemas com a função, qualidade do sono e incapacidade. Em todos os testes foi adotado um nível de significância de 5%. RESULTADOS: o grupo 2 apresentou níveis de dor à palpação muscular estatisticamente maiores que o grupo 1 (p<0,05). Ao se analisar a intensidade de dor subjetiva obtida através da EAV, o grupo 2 apresentou níveis maiores de dor subjetiva (EAV) em todas as medições, com significância estatística para "dor no momento" e "dor máxima" (p<0,05). Da mesma maneira, o grupo 2 mostrou níveis maiores, obtidos através da EAV, de problemas com humor, incapacidade, problemas com a função mandibular e problemas com sono/descanso, sendo que apenas o último apresentou significância estatística (p<0,05). CONCLUSÕES: a comorbidade enxaqueca exerce forte impacto na severidade da dor e na qualidade de vida de pacientes que apresentam diagnóstico primário de dor miofascial.

Temporomandibular disorders and migraine chronification

Among the established and potential comorbidities of migraine, the temporomandibular disorders (TMD) are rarely discussed, although they are of importance for several reasons. TMD may cause headaches per se, worsen existent primary headaches, and add to the burden of headache disorders. This article explores the potential comorbidity between migraine and TMD and the role of TMD as a potential factor to induce chronic migraine. We discuss the similarities between both conditions, review evidence to support the idea that both disorders are comorbid, and highlight the limited evidence suggesting that TMD influence migraine progression. Finally, we discuss the importance of cutaneous allodynia mediating the TMD/frequent headache relationship.

Prevalence of Facial Pain in Migraine: A Population-Based Study

Unilateral head pain focused on frontal, orbital or parietal regions is a leading symptom of migraine attacks. Rarely, head pain in migraine can extend involving the maxillary or mandibular region of the face, sometimes isolated facial pain is the only and atypical presentation of migraine. The prevalence of these unusual symptoms in migraine is unknown. We aimed to estimate the true prevalence of facial pain in migraine in a population-based sample of 517 migraine patients in Germany. In 46 (8.9%) cases migraine pain involved the head and the lower half of the face. Patients with facial pain suffer more trigemino-autonomic symptoms than migraine patients (47.8% vs. 7.9%; α2 = 66.23, P < 0.001). In one case isolated facial pain without headache was the leading symptom of migraine. Our results demonstrate that facial pain is not unusual in migraine, whereas isolated facial migraine is extremely rare.

Prevalence and characteristics of allodynia in headache sufferers: a population study

OBJECTIVE

The authors estimated the prevalence and severity of cutaneous allodynia (CA) in individuals with primary headaches from the general population.

METHODS

We mailed questionnaires to a random sample of 24,000 headache sufferers previously identified from the population. The questionnaire included the validated Allodynia Symptom Checklist (ASC) as well as measures of headache features, disability, and comorbidities. We modeled allodynia as an outcome using headache diagnosis, frequency and severity of headaches, and disability as predictor variables in logistic regression. Covariates included demographic variables, comorbidities, use of preventive medication, and use of opioids.

RESULTS

Complete surveys were returned by 16,573 individuals. The prevalence of CA of any severity (ASC score >or=3) varied with headache type. Prevalence was significantly higher in transformed migraine (TM, 68.3%) than in episodic migraine (63.2%, p < 0.01) and significantly elevated in both of these groups compared with probable migraine (42.6%), other chronic daily headaches (36.8%), and severe episodic tension-type headache (36.7%). The prevalence of severe CA (ASC score >or=9) was also highest in TM (28.5%) followed by migraine (20.4%), probable migraine (12.3%), other chronic daily headaches (6.2%), and severe episodic tension-type headache (5.1%). In the migraine and TM groups, prevalence of CA was higher in women and increased with disability score. Among migraineurs, CA increased with headache frequency and body mass index. In all groups, ASC scores were higher in individuals with major depression.

CONCLUSIONS

Cutaneous allodynia (CA) is more common and more severe in transformed migraine and migraine than in other primary headaches. Among migraineurs, CA is associated with female sex, headache frequency, increased body mass index, disability, and depression.