SARS-CoV-2 infection is associated with self-reported post-acute neuropsychological symptoms within six months of follow-up

BACKGROUND

Chronic neuropsychological sequelae following SARS-CoV-2 infection, including depression, anxiety, fatigue, and general cognitive difficulties, are a major public health concern. Given the potential impact of long-term neuropsychological impairment, it is important to characterize the frequency and predictors of this post-infection phenotype.

METHODS

The Epidemiology, Immunology, and Clinical Characteristics of Emerging Infectious Diseases with Pandemic Potential (EPICC) study is a longitudinal study assessing the impact of SARS-CoV-2 infection in U.S. Military Healthcare System (MHS) beneficiaries, i.e. those eligible for care in the MHS including active duty servicemembers, dependents, and retirees. Four broad areas of neuropsychological symptoms were assessed cross-sectionally among subjects 1-6 months post-infection/enrollment, including: depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), fatigue (PROMIS® Fatigue 7a), and cognitive function (PROMIS® Cognitive Function 8a and PROMIS® Cognitive Function abilities 8a). Multivariable Poisson regression models compared participants with and without SARS-CoV-2 infection history on these measures, adjusting for sex, ethnicity, active-duty status, age, and months post-first positive or enrollment of questionnaire completion (MPFP/E); models for fatigue and cognitive function were also adjusted for depression and anxiety scores.

RESULTS

The study population included 2383 participants who completed all five instruments within six MPFP/E, of whom 687 (28.8%) had at least one positive SARS-CoV-2 test. Compared to those who had never tested positive for SARS-CoV-2, the positive group was more likely to meet instrument-based criteria for depression (15.4% vs 10.3%, p<0.001), fatigue (20.1% vs 8.0%, p<0.001), impaired cognitive function (15.7% vs 8.6%, p<0.001), and impaired cognitive function abilities (24.3% vs 16.3%, p<0.001). In multivariable models, SARS-CoV-2 positive participants, assessed at an average of 2.7 months after infection, had increased risk of moderate to severe depression (RR: 1.44, 95% CI 1.12-1.84), fatigue (RR: 2.07, 95% CI 1.62-2.65), impaired cognitive function (RR: 1.64, 95% CI 1.27-2.11), and impaired cognitive function abilities (RR: 1.41, 95% CI 1.15-1.71); MPFP/E was not significant.

CONCLUSIONS

Participants with a history of SARS-CoV-2 infection were up to twice as likely to report cognitive impairment and fatigue as the group without prior SARS-CoV-2 infection. These findings underscore the continued importance of preventing SARS-CoV-2 infection and while time since infection/enrollment was not significant through 6 months of follow-up, this highlights the need for additional research into the long-term impacts of COVID-19 to mitigate and reverse these neuropsychological outcomes.

Guidelines of the International Headache Society for controlled trials of pharmacological preventive treatment for persistent post-traumatic headache attributed to mild traumatic brain injury

BACKGROUND

Persistent headache attributed to traumatic injury to the head is divided into two subtypes, one attributed to moderate or severe traumatic injury and another attributed to mild traumatic injury (i.e., concussion). The latter is much more prevalent, in part because more than 90% of cases with traumatic brain injury are classified as mild. The pathophysiology of persistent post-traumatic headache is poorly understood and the underlying mechanisms are likely multifactorial. There is currently no approved treatment specifically for persistent post-traumatic headache, and management strategies rely on medications used for migraine or tension-type headache. Therefore, high-quality trials are urgently needed to support clinical decision-making and optimize management strategies. International guidelines can facilitate appropriate trial design and ensure the acquisition of high-quality data evaluating the efficacy, tolerability, and safety of available and novel pharmacological therapies for the preventive treatment of persistent post-traumatic headache.

METHODS

The development of this guideline was based on a literature review of available studies in MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials, along with a review of previously published guidelines for controlled trials of preventive treatment for episodic and chronic migraine. The identified literature was critically appraised, and due to the scarcity of scientific evidence, recommendations were primarily based on the consensus of experts in the field.

OBJECTIVE

To provide guidelines for designing state-of-the-art controlled clinical trials aimed at evaluating the effectiveness of preventive treatments for persistent post-traumatic headache attributed to mild traumatic brain injury.

Decreased Self-reported Physical Fitness Following SARS-CoV-2 Infection and the Impact of Vaccine Boosters in a Cohort Study

Background

The long-term effects of coronavirus disease 2019 (COVID-19) on physical fitness are unclear, and the impact of vaccination on that relationship is uncertain.

Methods

We compared survey responses in a 1-year study of US military service members with (n = 1923) and without (n = 1591) a history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We fit Poisson regression models to estimate the association between history of SARS-CoV-2 infection and fitness impairment, adjusting for time since infection, demographics, and baseline health.

Results

The participants in this analysis were primarily young adults aged 18-39 years (75%), and 71.5% were male. Participants with a history of SARS-CoV-2 infection were more likely to report difficulty exercising (38.7% vs 18.4%; P < .01), difficulty performing daily activities (30.4% vs 12.7%; P < .01), and decreased fitness test (FT) scores (42.7% vs 26.2%; P < .01) than those without a history of infection. SARS-CoV-2-infected participants were at higher risk of these outcomes after adjusting for other factors (unvaccinated: exercising: adjusted risk ratio [aRR], 3.99; 95% CI, 3.36-4.73; activities: aRR, 5.02; 95% CI, 4.09-6.16; FT affected: aRR, 2.55; 95% CI, 2.19-2.98). Among SARS-CoV-2-positive participants, full vaccination before infection was associated with a lower risk of post-COVID-19 fitness impairment (fully vaccinated: exercise: aRR, 0.81; 95% CI, 0.70-0.95; activities: aRR, 0.76; 95% CI, 0.64-0.91; FT: aRR, 0.87; 95% CI, 0.76-1.00; boosted: exercise: aRR, 0.62; 95% CI, 0.51-0.74; activities: aRR, 0.52; 95% CI, 0.41-0.65; FT: aRR, 0.59; 95% CI, 0.49-0.70).

Conclusions

In this study of generally young, healthy military service members, SARS-CoV-2 infection was associated with lower self-reported fitness and exercise capacity; vaccination and boosting were associated with lower risk of self-reported fitness loss.

Plasma calcitonin gene-related peptide and nerve growth factor as headache and pain biomarkers in recently deployed soldiers with and without a recent concussion

OBJECTIVE

The objective of this study was to characterize the utility of calcitonin gene-related peptide (CGRP) and nerve growth factor (NGF) as potential biomarkers for headache and pain disorders in the post-military deployment setting.

BACKGROUND

The need to improve recognition, assessment, and prognoses of individuals with posttraumatic headache or other pain has increased interest in the potential of CGRP and NGF as biomarkers.

METHODS

The Warrior Strong Study (NCT01847040) is an observational longitudinal study of United States-based soldiers who had recently returned from deployment to Afghanistan or Iraq from 2009 to 2014. The present nested cross-sectional analysis uses baseline data collected from soldiers returning to Fort Bragg, North Carolina.

RESULTS

In total, 264 soldiers (mean (standard deviation [SD] age 28.1 [6.4] years, 230/264 [87.1%] men, 171/263 [65.0%] White) were analyzed. Mean (SD) plasma levels of CGRP were 1.3 (1.1) pg/mL and mean levels of NGF were 1.4 (0.4) pg/mL. Age was negatively correlated with NGF (-0.01 pg/mL per year, p = 0.007) but was not associated with CGRP. Men had higher mean (SD) CGRP plasma levels than women (1.4 95% confidence interval [CI; 1.2] vs. 0.9 95% CI [0.5] pg/mL, p < 0.002, Kruskal-Wallis test). CGRP levels were lower in participants who had a headache at the time of the blood draw (1.0 [0.6] pg/mL vs. 1.4 [1.2] pg/mL, p = 0.024). NGF was lower in participants with continuous pain (all types; 1.2 [0.4] vs. 1.4 [0.4] pg/mL, p = 0.027) and was lower in participants with traumatic brain injury (TBI) + posttraumatic headache (PTH) versus TBI without PTH (1.3 [0.3] vs. 1.4 [0.4] pg/mL, p = 0.021). Otherwise, CGRP and NGF were not associated with migraine-like headache, TBI status, or headache burden as measured by the number of medical encounters in crude or adjusted models.

CONCLUSION

In this exploratory study, plasma levels of NGF and CGRP showed promise as biomarkers for headache and other types of pain. These findings need to be replicated in other cohorts.

Assessing mean corpuscular volume as a screening tool for gestational vitamin B12 deficiency based on NHANES

Vitamin B12 can lead to neurological deficits. We assessed whether the mean corpuscular volume (MCV) could be a sufficiently sensitive measurement for abnormal serum methylmalonic Acid (MMA) and total plasma homocysteine (tHCY) (biomarkers of vitamin B12 or folate deficiency) and if so, at what cutoff value. A total of 26,397 participants (12,730 males and 13,667 females) were included in the analysis. Weighted analysis was performed using NHANES data to calculate crude/adjusted associations between MCV-MMA/tHCY, using linear regression. Unadjusted odds ratios (OR) 95% CIs were estimated from logistic regression models. Receiver Operating Curve and the Youden Index were used to identify the MCV level that most accurately distinguished those with abnormal MMA and tHCY (dependent variables) from those without. A positive and significant correlation between MCV-MMA/tHCY was found in the general population between ages 18-85, 0.95 (95% C.I. 0.75-1.17) and 2.61 (95% C.I. 2.15-3.08). In pregnant women, for every unit increase in MCV there was a 19% increase in odds of abnormal MMA, OR 1.19 (95% C.I. 1.08-1.31), p=0.001 and the Area Under the Curve for MCV as a test for abnormal MMA was 78%. An MCV cutoff of 93.1 correctly identified abnormal MMA in pregnant women with 81% sensitivity and 77% specificity. In the general population the MCV test performed poorly in identifying abnormal MMA/tHCY. MCV is an inexpensive measurement that may be useful to screen asymptomatic pregnant women for vitamin B12 abnormalities. This may have a significant impact on reducing adverse neurological outcomes in their children.

Persistent COVID-19 Symptoms at 6 Months After Onset and the Role of Vaccination Before or After SARS-CoV-2 Infection

IMPORTANCE

Understanding the factors associated with post-COVID conditions is important for prevention.

OBJECTIVE

To identify characteristics associated with persistent post-COVID-19 symptoms and to describe post-COVID-19 medical encounters.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from the Epidemiology, Immunology, and Clinical Characteristics of Emerging Infectious Diseases With Pandemic Potential (EPICC) study implemented in the US military health system (MHS); MHS beneficiaries aged 18 years or older who tested positive for SARS-CoV-2 from February 28, 2020, through December 31, 2021, were analyzed, with 1-year follow-up.

EXPOSURES

SARS-CoV-2 infection.

MAIN OUTCOMES AND MEASURES

The outcomes analyzed included survey-reported symptoms through 6 months after SARS-CoV-2 infection and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnosis categories reported in medical records 6 months following SARS-CoV-2 infection vs 3 months before infection.

RESULTS

More than half of the 1832 participants in these analyses were aged 18 to 44 years (1226 [66.9%]; mean [SD] age, 40.5 [13.7] years), were male (1118 [61.0%]), were unvaccinated at the time of their infection (1413 [77.1%]), and had no comorbidities (1290 [70.4%]). A total of 728 participants (39.7%) had illness that lasted 28 days or longer (28-89 days: 364 [19.9%]; ≥90 days: 364 [19.9%]). Participants who were unvaccinated prior to infection (risk ratio [RR], 1.39; 95% CI, 1.04-1.85), reported moderate (RR, 1.80; 95% CI, 1.47-2.22) or severe (RR, 2.25; 95% CI, 1.80-2.81) initial illnesses, had more hospitalized days (RR per each day of hospitalization, 1.02; 95% CI, 1.00-1.03), and had a Charlson Comorbidity Index score of 5 or greater (RR, 1.55; 95% CI, 1.01-2.37) were more likely to report 28 or more days of symptoms. Among unvaccinated participants, postinfection vaccination was associated with a 41% lower risk of reporting symptoms at 6 months (RR, 0.59; 95% CI, 0.40-0.89). Participants had higher risk of pulmonary (RR, 2.00; 95% CI, 1.40-2.84), diabetes (RR, 1.46; 95% CI, 1.00-2.13), neurological (RR, 1.29; 95% CI, 1.02-1.64), and mental health-related medical encounters (RR, 1.28; 95% CI, 1.01-1.62) at 6 months after symptom onset than at baseline (before SARS-CoV-2 infection).

CONCLUSIONS AND RELEVANCE

In this cohort study, more severe acute illness, a higher Charlson Comorbidity Index score, and being unvaccinated were associated with a higher risk of reporting COVID-19 symptoms lasting 28 days or more. Participants with COVID-19 were more likely to seek medical care for diabetes, pulmonary, neurological, and mental health-related illness for at least 6 months after onset compared with their pre-COVID baseline health care use patterns. These findings may inform the risk-benefit ratio of COVID-19 vaccination policy.

The relationship between prior psychiatric diagnosis and brain cancer diagnosis in the U.S. military health system

PURPOSE

Prior research suggested the increased likelihood of brain cancer diagnosis following certain psychiatric diagnoses. This association may result from detection bias or suggest an early sign for brain cancer. This study investigated whether psychiatric illness may be an early manifestation of brain cancer while considering potential effects of detection bias.

METHODS

This case-control study used the data from the Department of Defense's Central Cancer Registry and the Military Health System Data Repository. Four cancer-free controls and one negative-outcome control (cancers not associated with psychiatric illness) were matched to each brain cancer case diagnosed from 1998 to 2013 by age, sex, race, and military status. The groups were compared in the likelihood of having a pre-existing psychiatric diagnosis using conditional logistic regression.

RESULTS

We found a significant association of psychiatric illnesses with brain cancer (Odds Ratio (OR) = 2.63, 95% confidence interval (CI) = 2.18-3.16) and other cancers (OR = 1.80, 95% CI = 1.49-2.19), compared to non-cancer controls. The association was stronger for psychiatric diagnoses within three months before cancer (brain cancer: OR = 26.77, 95% CI = 15.40-46.53; other cancers: OR = 4.12, 95% CI = 1.96-8.65). The association with psychiatric disorders within 3 months were higher for small brain tumors (OR = 128.32, 95% CI = 17.28-952.92 compared to non-cancer controls) while the OR was 2.79 for other cancers (95% CI = 0.86-8.99 compared to non-cancer controls).

CONCLUSION

Our findings suggest an association between diagnosed psychiatric illnesses and subsequent brain cancer diagnosis, which may not be solely explained by detection bias. Psychiatric illness might be a sign for early detection of brain cancer beyond the potential effects of detection bias.

An Analysis of SARS-CoV-2 Vaccine Reactogenicity: Variation by Type, Dose, and History, Severity, and Recency of Prior SARS-CoV-2 Infection

Background

There is limited information on the functional consequences of coronavirus disease 2019 (COVID-19) vaccine side effects. To support patient counseling and public health messaging, we describe the risk and correlates of COVID-19 vaccine side effects sufficient to prevent work or usual activities and/or lead to medical care (“severe” side effects).

Methods

The EPICC study is a longitudinal cohort study of Military Healthcare System beneficiaries including active duty service members, dependents, and retirees. We studied 2789 adults who were vaccinated between December 2020 and December 2021.

Results

Severe side effects were most common with the Ad26.COV2.S (Janssen/Johnson and Johnson) vaccine, followed by mRNA-1273 (Moderna) then BNT162b2 (Pfizer/BioNTech). Severe side effects were more common after the second than first dose (11% vs 4%; P < .001). First (but not second) dose side effects were more common in those with vs without prior severe acute respiratory syndrome coronavirus 2 infection (9% vs 2%; adjusted odds ratio [aOR], 5.84; 95% CI, 3.8–9.1), particularly if the prior illness was severe or critical (13% vs 2%; aOR, 10.57; 95% CI, 5.5–20.1) or resulted in inpatient care (17% vs 2%; aOR, 19.3; 95% CI, 5.1–72.5). Side effects were more common in women than men but not otherwise related to demographic factors.

Conclusions

Vaccine side effects sufficient to prevent usual activities were more common after the second than first dose and varied by vaccine type. First dose side effects were more likely in those with a history of COVID-19—particularly if that prior illness was severe or associated with inpatient care. These findings may assist clinicians and patients by providing a real-world evaluation of the likelihood of experiencing impactful postvaccine symptoms.

Understanding "Hybrid Immunity": Comparison and Predictors of Humoral Immune Responses to Severe Acute Respiratory Syndrome Coronavirus 2 Infection (SARS-CoV-2) and Coronavirus Disease 2019 (COVID-19) Vaccines

BACKGROUND

Comparison of humoral responses in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinees, those with SARS-CoV-2 infection, or combinations of vaccine/ infection ("hybrid immunity") may clarify predictors of vaccine immunogenicity.

METHODS

We studied 2660 US Military Health System beneficiaries with a history of SARS-CoV-2 infection-alone (n = 705), vaccination-alone (n = 932), vaccine-after-infection (n = 869), and vaccine-breakthrough-infection (n = 154). Peak anti-spike-immunoglobulin G (IgG) responses through 183 days were compared, with adjustment for vaccine product, demography, and comorbidities. We excluded those with evidence of clinical or subclinical SARS-CoV-2 reinfection from all groups.

RESULTS

Multivariable regression results indicated that vaccine-after-infection anti-spike-IgG responses were higher than infection-alone (P < .01), regardless of prior infection severity. An increased time between infection and vaccination was associated with greater post-vaccination IgG response (P < .01). Vaccination-alone elicited a greater IgG response but more rapid waning of IgG (P < .01) compared with infection-alone (P < .01). BNT162b2 and mRNA-1273 vaccine-receipt was associated with greater IgG responses compared with JNJ-78436735 vaccine-receipt (P < .01), regardless of infection history. Those with vaccine-after-infection or vaccine-breakthrough-infection had a more durable anti-spike-IgG response compared to infection-alone (P < .01).

CONCLUSIONS

Vaccine-receipt elicited higher anti-spike-IgG responses than infection-alone, although IgG levels waned faster in those vaccinated (compared to infection-alone). Vaccine-after-infection elicits a greater humoral response compared with vaccine or infection alone; and the timing, but not disease severity, of prior infection predicted these post-vaccination IgG responses. While differences between groups were small in magnitude, these results offer insights into vaccine immunogenicity variations that may help inform vaccination timing strategies.

Longitudinal analysis reveals high prevalence of Epstein-Barr virus associated with multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system of unknown etiology. We tested the hypothesis that MS is caused by Epstein-Barr virus (EBV) in a cohort comprising more than 10 million young adults on active duty in the US military, 955 of whom were diagnosed with MS during their period of service. Risk of MS increased 32-fold after infection with EBV but was not increased after infection with other viruses, including the similarly transmitted cytomegalovirus. Serum levels of neurofilament light chain, a biomarker of neuroaxonal degeneration, increased only after EBV seroconversion. These findings cannot be explained by any known risk factor for MS and suggest EBV as the leading cause of MS.

Post-traumatic headache attributed to traumatic brain injury: classification, clinical characteristics, and treatment

Post-traumatic headache is a common sequela of traumatic brain injury and is classified as a secondary headache disorder. In the past 10 years, considerable progress has been made to better understand the clinical features of this disorder, generating momentum to identify effective therapies. Post-traumatic headache is increasingly being recognised as a heterogeneous headache disorder, with patients often classified into subphenotypes that might be more responsive to specific therapies. Such considerations are not accounted for in three iterations of diagnostic criteria published by the International Headache Society. The scarcity of evidence-based approaches has left clinicians to choose therapies on the basis of the primary headache phenotype (eg, migraine and tension-type headache) and that are most compatible with the clinical picture. A concerted effort is needed to address these shortcomings and should include large prospective cohort studies as well as randomised controlled trials. This approach, in turn, will result in better disease characterisation and availability of evidence-based treatment options.

Headache complexity (number of symptom features) differentiates post-traumatic from non-traumatic headaches

BACKGROUND

Post-traumatic headaches are a common sequela of mild traumatic brain injury (concussion). It is unclear whether or how these headaches differ phenotypically from primary headaches.

OBJECTIVE

Determine whether there is an overarching unobserved latent trait that drives the expression of observed features of post-traumatic headache and other headaches.

METHODS

Data from this post-hoc analysis come from the Warrior Strong Cohort Study conducted from 2010 through 2015. Approximately 25,000 soldiers were screened for concussion history at routine post-deployment health assessments. A random sample was invited to participate, enrolling 1567. Twelve observed headache phenotypic features were used to measure "headache complexity", the latent trait of clinical interest, using single factor confirmatory factor analysis. We compared headache complexity between groups and determined whether headache complexity predicted accessing medical care for headache.

RESULTS

Of 1094 soldiers with headaches, 198 were classified as having post-traumatic headache. These headaches were compared to those in the other soldiers (647 without concussion history and 249 with concussion history). Soldiers with post-traumatic headache had greater endorsement of all 12 headache features compared to the soldiers with non-concussive headaches. The confirmatory factor analysis showed good model fit (χ² (51) = 95.59, p = 0.0002, RMSEA = 0.03, comparative fit index = 0.99, and Tucker-Lewis index = 0.99), providing empirical support for the headache complexity construct. Soldier groups differed in their mean headache complexity level (p < 0.001) such that post-traumatic headache soldiers had greater headache complexity compared to non-concussed soldiers (standardized mean difference = 0.91, 95% confidence interval: 0.72-1.09, p < 0.001 and to concussed soldiers with coincidental headaches standardized mean difference = 0.75, 95% confidence interval: 0.53-0.96, p < 0.001). Increasing headache complexity predicted medical encounters for headache (odds ratio = 1.87, 95% confidence interval: 1.49-2.35, p < 0.001) and migraine (odds ratio = 3.74, 95% confidence interval: 2.33-5.98, p < 0.001) during the year following deployment.Conclusions and relevance: The current study provided support for a single latent trait, characterized by observed headache symptoms, that differentiates between concussive and non-concussive headaches and predicts use of medical care for headache. The single trait confirmatory factor analysis suggests that post-traumatic headaches differ from non-concussive headaches by severity more than kind, based on the symptoms assessed.ClinicalTrials.gov identifier NCT01847040.

Serum Neurofilament Light Chain Levels in Patients With Presymptomatic Multiple Sclerosis

Importance

Unrecognized demyelinating events often precede the clinical onset of multiple sclerosis (MS). Identification of these events at the time of occurrence would have implications for early diagnosis and the search of causal factors for the disease.

Objective

To assess whether serum neurofilament light chain (sNfL) levels are elevated before the clinical MS onset.

Design, Setting, and Participants

Nested case-control study among US military personnel who have serum samples stored in the US Department of Defense Serum Repository. Serum samples were collected from 2000 to 2011; sNfL assays and data analyses were performed from 2018 to 2019. We selected 60 case patients with MS who either had 2 samples collected before onset (mean follow-up, 6.3 years) or 1 sample collected before and 1 after onset (mean follow-up, 1.3 years), among 245 previously identified case patients. For each case, we randomly selected 1 of 2 previously identified control individuals matched by age, sex, race/ethnicity, and dates of sample collection. The sample size was chosen based on the available funding.

Exposures

Serum NfL concentrations measured using an ultrasensitive single-molecule array assay (Simoa).

Main Outcomes and Measurements

Log-transformed sNfL concentrations in case patients and control individuals compared using conditional logistic regression and linear mixed models.

Results

Mean age at baseline was 27.5 years, and 92 of 120 participants (76.7%) were men. Serum NfL levels were higher in case patients with MS compared with their matched control individuals in samples drawn a median of 6 years (range, 4-10 years) before the clinical onset (median, 16.7 pg/mL; interquartile range [IQR], 12.6-23.1 pg/mL vs 15.2 pg/m; IQR, 10.3-19.9 pg/mL; P = .04). This difference increased with decreasing time to the case clinical onset (estimated coefficient for interaction with time = 0.063; P = .008). A within-person increase in presymptomatic sNfL levels was associated with higher MS risk (rate ratio for ≥5 pg/mL increase, 7.50; 95% CI, 1.72-32.80). The clinical onset was associated with a marked increase in sNfL levels (median, 25.0; IQR, 17.1-41.3 vs 45.1; IQR, 27.0-102.7 pg/mL for presymptomatic and postonset MS samples; P = .009).

Conclusions and Relevance

The levels of sNfL were increased 6 years before the clinical MS onset, indicating that MS may have a prodromal phase lasting several years and that neuroaxonal damage occurs already during this phase.

Current patterns of primary care provider practices for the treatment of post-traumatic headache in active duty military settings

Objective

To provide a preliminary assessment of the current clinical practice for the treatment of post-traumatic headache following concussion in military primary health care settings.

Background

Headache is one of the most common symptoms post-concussion; however, little is known of the current clinical practices of primary care providers (on the treatment of post-traumatic headache), particularly in military settings.

Methods

Study participants were primary care providers (n = 65) who treated active duty Service members suffering from post-traumatic headache at two military installations. Qualitative data gathered via semi-structured interviews were used to describe provider practices and experience in treating patients with post-traumatic headache.

Results

Some patterns of care across primary care providers treating post-traumatic headache were consistent with the Department of Defense-recommended clinical recommendation (e.g., recommendation of both pharmacological and non-pharmacological treatment [89.4%]; engaging in follow-up care [100%]). Differences existed in timing of follow-up from initial visit [16.9% reporting within 24 hours; 21.5% reporting within 48–72 hours; and 26.2% reporting more than 1 week], the factors contributing to the type of care given (e.g., symptomatology [33.0%], injury characteristic [24.2%], patient characteristic [13.2%]) and the need for referral to higher level of care (e.g., symptomatology [44.6%], treatment failure [25.0%]). These variations may be indicative of individualized treatment which would be compliant with best clinical practice.

Conclusion

The results of this study demonstrate the current clinical practice in military primary care settings for the treatment of post-traumatic headache which can potentially inform and improve implementation of provider training and education.

The prevalence of hypnic headache in Iceland

OBJECTIVE

To determine the prevalence of hypnic headache.

BACKGROUND

The exact prevalence of hypnic headache is unknown since there are no published population-based prevalence studies.

METHODS

This study was a pilot for the SAGA cohort study, a population-based study on life stressors and various indices of health. Of 1398 invited adults, 921 (66%) participated; 402 men (average age 45.6 years, SD 13.2) and 519 women (52.6 years, SD 11.1). Subjects answered a headache questionnaire including a screening question for hypnic headache. "Do you have a headache that occurs only during sleep and causes wakening?". Diagnosis of hypnic headache was made by clinical interview using ICHD-3 criteria.

RESULTS

Among 921 participants, six screened positive for hypnic headache, of those two 0.22% (95% CI 0.06-0.79%) had probable hypnic headache and none had definite hypnic headache.

CONCLUSION

Confirming that hypnic headache is rare, these data suggest a 0.22% prevalence of probable hypnic headache.

Severe Upper Limb Injuries in U.S. Military Personnel: Incidence, Risk Factor and Outcomes

BACKGROUND

Severe upper limb injuries (SULI) may pose a significant public health challenge for the military; however, SULI has not been previously defined or studied in the US military. Objective: Determine SULI incidence, risk factors, and outcomes.

MATERIALS AND METHODS

Active Component (AC) U.S. military personnel who served during January 1, 2003 to December 31, 2012 who met the case definition for SULI (N = 213,745) and a random sample from the same population without SULI were included. Data from the Defense Medical Surveillance System and Defense Medical Epidemiology Database was used to calculate incidence. Multiple logistic regression and Cox proportional hazards models were used to analyze SULI risk factors and attrition.

RESULTS

SULI incidence was 15/1,000 person-years. Higher SULI risk was observed in men (OR 1.25; 95% CI 1.22-1.27), age 25-29 (OR 1.07; 95% CI 1.05-1.09) compared to age 20-24, E5-E9 (OR 1.14; 95% CI 1.12-1.17) compared to E1-E4, serving in Coast guard (OR 1.62; 95% CI 1.56-1.68) and Air Force (OR 1.17; 95% CI 1.14-1.19) relative to Army and with a deployment history (OR 2.16, 95% CI 2.12-2.19) while SULI risk was lower for blacks (OR 0.91; 95% CI 0.90-0.93) and those in the "other race" category (HR 0.81; 95% CI 0.80-0.84) compared to whites. SULI was associated with 23% increased risk of attrition (HR 1.23; 95% CI 1.22-1.24).

CONCLUSION

The study findings provide preliminary evidence on the incidence, natural history and distribution of SULI in this population. The findings indicate SULI may impact readiness and result in premature military separation.

Posttraumatic vs nontraumatic headaches: A phenotypic analysis in a military population

OBJECTIVE

To describe and compare phenotypic features of posttraumatic headaches (PTH) and headaches unrelated to concussion.

METHODS

Participants are a random sample of recently deployed soldiers from the Warrior Strong cohort, consisting of soldiers with (n = 557) and without (n = 1,030) a history of a recent mild traumatic brain injury (mTBI; concussion). mTBI+ soldiers were subdivided as PTH+ (n = 230) and PTH- (n = 327). Headache classification was based on a detailed phenotypic questionnaire. Medical encounters for headache were documented for the year after deployment.

RESULTS

The findings here are limited to the soldiers with headaches, consisting of 94% of the mTBI+ soldiers and 76% of the mTBI- soldiers. Other than headache duration, all headache/migraine features were more common or more severe in the PTH+ group compared to the nonconcussed group (mTBI-) and compared to the concussed group with nontraumatic headaches (PTH-). Headaches were largely similar in the mTBI- and PTH- groups. The features most specific to PTH+ included allodynia, visual aura, sensory aura, daily headache, and continuous headache. Medical consultation for headache was most common in the PTH+ group (62%) vs the PTH- group (20%) or the mTBI- group (13%) (p < 0.008).

CONCLUSIONS

In this cohort of recently deployed soldiers, PTHs are more severe, frequent, and migraine-like and more often associated with medical consultation compared to headaches presumed unrelated to concussion. Future observational studies are needed to verify and characterize the PTH phenotype, which could be followed by treatment trials with appropriate and possibly novel outcomes for prespecified subgroups.

CLINICALTRIALSGOV IDENTIFIER

NCT01847040.

Characterization of lifetime TBIs in a cohort of recently deployed soldiers: The warrior strong study

OBJECTIVE

To describe and characterize the lifetime history of traumatic brain injury (TBI) among active duty soldiers returning from deployment to Afghanistan or Iraq.

METHOD

Data were extracted from a larger parent study that was conducted at two large United States Army bases between 2009 and 2014 during Post-Deployment Health Assessment. The sample included 1,060 soldiers who sustained at least one TBI during their lifetime.

RESULTS

The Ohio State University TBI-Identification Method interview was administered to characterize individuals' total lifetime history of TBI. Soldiers reported sustaining a median of 2 lifetime TBIs. Slightly more than half of the sample without a most recent deployment-related TBI still reported a history of a lifetime TBI (some of which occurred during previous deployments). Most lifetime injuries reported were of mild severity; however, 6% of individuals reported a history of moderate/severe TBI. Blast was the most frequent mechanism associated with recent deployment-related mild TBIs.

CONCLUSION

Findings suggest that soldiers who screened positive, as well as those who screened negative, for a history of TBI during their recent deployment still endorsed a lifetime history of TBI. Future research is needed to explore the functional impact of multiple TBIs over one's lifetime to help inform screening, assessment, and treatment among military personnel. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Trajectory of Postconcussive Symptoms 12 Months After Deployment in Soldiers With and Without Mild Traumatic Brain Injury: Warrior Strong Study

We analyzed data from a cohort of recently deployed soldiers from 2 US Army bases, Fort Carson and Fort Bragg (2009 to 2015). Soldiers with and without a recent history of mild traumatic brain injury (mTBI) on deployment were evaluated within days of return and at 3, 6, and 12 months. Those with mTBI were more likely than those without to endorse ≥1 postconcussive symptom as "severe" and/or "very severe" (47% vs. 21%, baseline; adjusted relative risk (RR) = 1.71, 95% confidence interval: 1.51, 1.93, all time points), which remained significant after adjusting for posttraumatic stress disorder (adjusted RR = 1.34, 95% confidence interval: 1.20, 1.50). Prevalence and relative risks for 3 of the most common baseline symptoms remained constant over time: sleep problems (RR = 2.19), forgetfulness (RR = 2.56), and irritability (RR = 2.73). The pattern was slightly different for headache (baseline, RR = 3.44; 12 months, RR = 3.26), due to increased prevalence of headache in those without mTBI. The prevalence of clinically relevant postconcussive symptoms remained relatively constant over 1 year of follow-up, whether or not symptoms were associated with concussion. Service members with recent mTBI reported more symptoms than those without at all time points.

Epidemiology of migraine in men: Results from the Chronic Migraine Epidemiology and Outcomes (CaMEO) Study

OBJECTIVE

To assess migraine epidemiology in men by examining gender differences in disease presentation, comorbidities, and prognosis.

PATIENTS AND METHODS

The Chronic Migraine Epidemiology and Outcomes (CaMEO) Study is a longitudinal survey of US adults with migraine identified by web questionnaire. Data were stratified by gender, collected between September 2012-November 2013, and included sociodemographics, headache features, Migraine Disability Assessment, Migraine Symptom Severity Score, Allodynia Symptom Checklist, and comorbidities. Discrete time hazard models addressed 1-year likelihood of transition from episodic to chronic migraine headache frequency.

RESULTS

Of the 16,789 migraine respondents, 4294 were men (25.6%). Compared to women, men were slightly older at onset of their headaches (mean 24.1 vs. 22.3 years) and had fewer headache days/month (4.3 vs. 5.3 days), slightly less severe attacks (Migraine Symptom Severity Score, 21.6 vs. 22.6), reduced frequencies of grade IV Migraine Disability Assessment scores (15.7% vs. 24.1%), allodynia (32.6% vs. 49.7%), chronic migraine (6.5% vs. 9.6%, each p < 0.001), and common comorbidities. Men were less likely to report consulting a doctor for their headaches and receiving a migraine diagnosis if they consulted. Men and women with episodic migraine had similar crude 1-year risk of chronic migraine onset. Controlling for known risk factors (i.e. depression, headache frequency, allodynia), men had greater likelihood of chronic migraine onset at 6, 9, and 12 months (each p < 0.05).

CONCLUSIONS

Findings confirmed gender differences. Men with migraine generally have less severe attacks and disability and are less likely to receive a diagnosis than women with migraine. Prognostic factors may be better understood for women than men.

Fluctuations in episodic and chronic migraine status over the course of 1 year: implications for diagnosis, treatment and clinical trial design

Background

Relatively little is known about the stability of a diagnosis of episodic migraine (EM) or chronic migraine (CM) over time. This study examines natural fluctuations in self-reported headache frequency as well as the stability and variation in migraine type among individuals meeting criteria for EM and CM at baseline.

Methods

The Chronic Migraine Epidemiology and Outcomes (CaMEO) Study was a longitudinal survey of US adults with EM and CM identified by a web-questionnaire. A validated questionnaire was used to classify respondents with EM (<15 headache days/month) or CM (≥15 headache days/month) every three months for a total of five assessments. We described longitudinal persistence of baseline EM and CM classifications. In addition, we modelled longitudinal variation in headache day frequency per month using negative binomial repeated measures regression models (NBRMR).

Results

Among the 5464 respondents with EM at baseline providing four or five waves of data, 5048 (92.4%) had EM in all waves and 416 (7.6%) had CM in at least one wave. Among 526 respondents with CM at baseline providing four or five waves of data, 140 (26.6%) had CM in every wave and 386 (73.4%) had EM for at least one wave. Individual plots revealed striking within-person variations in headache days per month. The NBRMR model revealed that the rate of headache days increased across waves of observation 19% more per wave for CM compared to EM (rate ratio [RR], 1.19; 95% CI, 1.13–1.26). After adjustment for covariates, the relative difference changed to a 26% increase per wave (RR, 1.26; 95% CI, 1.2–1.33).

Conclusions

Follow-up at three-month intervals reveals a high level of short-term variability in headache days per month. As a consequence, many individuals cross the CM diagnostic boundary of ≥15 headache days per month.Nearly three quarters of persons with CM at baseline drop below this diagnostic boundary at least once over the course of a year. These findings are of interest in the consideration of headache classification and diagnosis, the design and interpretation of epidemiologic and clinical studies, and clinical management.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-017-0787-1) contains supplementary material, which is available to authorized users.

Medication overuse headache: An entrenched idea in need of scrutiny

It is a widely accepted idea that medications taken to relieve acute headache pain can paradoxically worsen headache if used too often. This type of secondary headache is referred to as medication overuse headache (MOH); previously used terms include rebound headache and drug-induced headache. In the absence of consensus about the duration of use, amount, and type of medication needed to cause MOH, the default position is conservative. A common recommendation is to limit treatment to no more than 10 or 15 days per month (depending on medication type) to prevent headache frequency progression. Medication withdrawal is often recommended as a first step in treatment of patients with very frequent headaches. Existing evidence, however, does not provide a strong basis for such causal claims about the relationship between medication use and frequent headache. Observational studies linking treatment patterns with headache frequency are by their nature confounded by indication. Medication withdrawal studies have mostly been uncontrolled and often have high dropout rates. Evaluation of this evidence suggests that only a minority of patients required to limit the use of symptomatic medication may benefit from treatment limitation. Similarly, only a minority of patients deemed to be overusing medications may benefit from withdrawal. These findings raise serious questions about the value of withholding or withdrawing symptom-relieving medications from people with frequent headaches solely to prevent or treat MOH. The benefits of doing so are smaller, and the harms larger, than currently recognized. The concept of MOH should be viewed with more skepticism. Until the evidence is better, we should avoid dogmatism about the use of symptomatic medication. Frequent use of symptom-relieving headache medications should be viewed more neutrally, as an indicator of poorly controlled headaches, and not invariably a cause.

Comorbid pain and migraine chronicity: The Chronic Migraine Epidemiology and Outcomes Study

Objective:

To identify patterns of noncephalic pain comorbidity in people with episodic migraine (EM; <15 headache-days per month) and chronic migraine (CM; ≥15 headache-days per month) and to examine whether the presence of noncephalic pain is an indicator for the 3-month onset or persistence of CM.

Methods:

Data from the Chronic Migraine Epidemiology and Outcomes (CaMEO) Study, a prospective, web-based study with cross-sectional modules embedded in a longitudinal design, were analyzed at baseline and the 3-month follow-up. Relationships between the number of noncephalic pain sites and 3-month onset of CM or persistent CM were assessed.

Results:

Of 8,908 eligible respondents, 8,139 (91.4%) had EM and 769 (8.6%) had CM at baseline. At 3 months, the incidence of CM among those with baseline EM was 3.4%. When adjusted for demographics and headache-day frequency, the odds of CM onset among those with baseline EM increased by 30% (95% confidence interval [CI] 1.21–1.40, p < 0.001) for each additional noncephalic pain site at baseline. Among those with CM at baseline, 50.1% had persistent CM at the 3-month follow-up. After adjustment for demographics, individuals with CM were 15% (95% CI 1.07–1.25, p < 0.001) more likely to have persistent CM for each additional noncephalic pain site at baseline.

Conclusions:

These results suggest that noncephalic pain may be a marker for headache chronicity that could be used to identify people with EM at risk of the onset of CM and people with CM at risk of persistent CM.

Epidemiology and prognosis of mild traumatic brain injury in returning soldiers

Objective:

Mild traumatic brain injury (mTBI; concussion) is common in returning service members yet limited definitive evidence exists on its prognosis.

Methods:

Almost 25,000 non–medically evacuated soldiers returning from Afghanistan or Iraq to 2 military bases between 2009 and 2014 were screened for mTBI. We invited a random sample to participate in the present study, oversampling those screening positive, resulting in 557 mTBI cases and 1,010 controls, of whom 366 cases and 599 controls completed 3-month follow-up evaluations. The criterion measure of screened mTBI was the Ohio State University Traumatic Brain Injury Identification Method. Postconcussive symptoms (PCS) were measured at follow-up with the Neurobehavioral Symptom Inventory. Symptoms reported at a severe or very severe level were considered clinically relevant.

Results:

About half (47%) of soldiers who had sustained an mTBI during this latest deployment reported PCS at 3-month follow-up vs 25% of controls: adjusted odds ratio 2.4 (1.8–3.2). The most commonly reported symptoms (cases vs controls) were sleep problems (30% vs 14%), forgetfulness (21% vs 9%), irritability (17% vs 8%), and headaches (15% vs 5%). mTBI cases were about twice as likely as controls to report receiving rehabilitative services and fair or poor health. Other predictors of PCS included posttraumatic stress, combat exposure, and noncephalic pain. A majority of both cases and controls reported traumatic brain injuries predating this latest deployment.

Conclusions:

In this nonclinical population of recently deployed soldiers, a substantial proportion of those who had sustained an mTBI were symptomatic 3 months postdeployment. Future studies need to include longer follow-up to measure symptom resolution.

Clinicaltrials.gov identifier:

NCT01847040.

Impact of Migraine on the Family: Perspectives of People With Migraine and Their Spouse/Domestic Partner in the CaMEO Study

OBJECTIVE

To assess the impact of migraine on family members, activities, and relationships from the perspectives of the person with migraine and his or her spouse/domestic partner.

PATIENTS AND METHODS

The Chronic Migraine Epidemiology and Outcomes (CaMEO) study is a longitudinal, Web-based study conducted from September 2012 to November 2013. Quota sampling from an online panel identified respondents who met modified International Classification of Headache Disorders, version 3 beta migraine criteria. The Family Burden Module included 24 items covering 6 domains. Findings for respondents with episodic migraine (EM) and chronic migraine (CM) are presented for both the affected individuals and their partners.

RESULTS

Among 13,064 Family Burden Module respondents (65.7% response rate), there were 4022 migraineur-spouse dyads, including 2275 dyads with children. Burden increased with headache frequency across all 6 domains. People with migraine reported higher family burden due to migraine than did their spouse/partner. Reduced participation in family activities due to migraine was reported 1 or more times a month among 48.2% to 57.4% of migraineurs, depending on headache frequency (days/month). Many (low-frequency to high-frequency EM, 24.4%-40.4%; CM, 43.9%) perceived that their spouse/partner did not believe the severity/impact of their headaches. One-third of migraineurs stated that they worried about long-term financial security for themselves or their family because of their headaches. Many migraineurs felt they would be better parents without headaches (low-frequency to high-frequency EM, 29.9%-58.0%; CM, 71.7%).

CONCLUSION

This analysis quantified the pervasive burden of migraine on the family, highlighting the impact on family activities and relationships. Not surprisingly, the impact was greatest in families of people with CM.

Adipokines and Migraine: A Systematic Review

BACKGROUND

Migraine is comorbid with obesity. Recent research suggests an association between migraine and adipocytokines, proteins that are predominantly secreted from adipose tissue and which participate in energy homeostasis and inflammatory processes.

OBJECTIVES

In this review, we first briefly discuss the association between migraine and obesity and the importance of adipose tissue as a neuroendocrine organ. We then present a systematic review of the extant literature evaluating circulating levels of adiponectin and leptin in those with migraine.

METHODS

A search of the PubMed database was conducted using the keywords "migraine," "adiponectin," and "leptin." In addition reference lists of relevant articles were reviewed for possible inclusion. English language studies published between 2005 and 2015 evaluating circulating blood concentration of adiponectin or leptin in those with migraine were included.

CONCLUSIONS

While the existing data are suggestive that adipokines may be associated with migraine, substantial study design differences and conflicting results limit definitive conclusions. Future research utilizing carefully considered designs and methodology is warranted. In particular careful and systematic characterization of pain states at the time of samples, as well as systematic consideration of demographic (e.g., age, sex) and other vital covariates (e.g., obesity status, lipids) are needed to determine if adipokines play a role in migraine pathophysiology and if any adipokine represents a viable, novel migraine biomarker, or drug target.

The Impact of Post-Traumatic Stress Disorder on the Burden of Migraine: Results From the National Comorbidity Survey-Replication

BACKGROUND

Post-traumatic stress disorder (PTSD) has been linked with migraine in prior studies.

OBJECTIVE

To evaluate the individual and joint burdens of migraine and PTSD in a population-based cohort.

METHODS

The National Comorbidity Survey-Replication (NCS-R) is a general population study conducted in the United States from February 2001-April 2003. PTSD and migraine were assessed, and four groups defined based on their migraine and PTSD status. The four groups included those with no migraine and no PTSD (controls, n=4535), those with migraine and without PTSD (migraine alone, n=236), those with PTSD and without migraine (PTSD alone, n=244), and those with both migraine and PTSD (mig+PTSD, n=68). Logistic and Poisson regression models were used to assess the association between dichotomous/multilevel outcome variables indicating financial, health, and interpersonal burdens and each migraine/PTSD group.

RESULTS

Compared to controls, those with Mig+PTSD were more likely to be in the low poverty index (48% vs 41%, AOR 2.16; CI: 1.10, 4.24) and were less likely to be working for pay or profit in the past week (50% vs 68%, AOR 0.42; CI: 0.24, 0.74) but not those with migraine or PTSD alone. Additionally, the number of days where work quality was cut due to physical or mental health or substance abuse in the past month was greater in all groups compared to controls: (1) migraine alone: mean 2.57 (SEM 0.32) vs mean 1.09 (SEM 0.08) days, ARR=2.39; CI: 2.19, 2.62; (2) PTSD alone: mean 2.43 (SEM 0.33) vs mean 1.09 (SEM 0.08) days, ARR=2.09; CI: 1.91, 2.29; (3) mig+PTSD: mean 8.2 (SEM 0.79) vs 1.09 (SEM 0.08) days, ARR 6.79; CI 6.16, 7.49; and was over 2.5-fold greater in those mig+PTSD than migraine alone (mean 8.0 [SEM 0.79] vs 2.6 days [SEM 0.72], ARR 2.77; CI: 2.45, 3.14). The likelihood of having difficulty getting along or maintaining a social life was also increased in all groups relative to controls: (1) migraine alone: 21% vs 5.4%, AOR 4.20; CI: 2.62, 6.74; (2) PTSD alone: 18% vs 5.4%, AOR 3.40; CI: 2.40, 4.82; (3) Mig+PTSD: 39% vs 5.4%, AOR 9.95; CI: 5.72, 17.32, and was 2-fold greater in those with Mig+PTSD as compared to those with migraine alone (AOR 2.32; CI: 1.15, 4.69).

CONCLUSIONS

These findings support the need for those who treat migraine patients to be aware of the comorbidity with PTSD, as these patients may be particularly prone to adverse financial, health, and interpersonal disease burdens.

Ictal adipokines are associated with pain severity and treatment response in episodic migraine

OBJECTIVE

To evaluate ictal adipokine levels in episodic migraineurs and their association with pain severity and treatment response.

METHODS

This was a double-blind, placebo-controlled trial evaluating peripheral blood specimens from episodic migraineurs at acute pain onset and 30 to 120 minutes after treatment with sumatriptan/naproxen sodium vs placebo. Total adiponectin (T-ADP), ADP multimers (high molecular weight [HMW], middle molecular weight, and low molecular weight [LMW]), leptin, and resistin levels were evaluated by immunoassays.

RESULTS

Thirty-four participants (17 responders, 17 nonresponders) were included. In all participants, pretreatment pain severity increased with every quartile increase in both the HMW:T-ADP ratio (coefficient of variation [CV] 0.51; 95% confidence interval [CI]: 0.08, 0.93; p = 0.019) and resistin levels (CV 0.58; 95% CI: 0.21, 0.96; p = 0.002), but was not associated with quartile changes in leptin levels. In responders, T-ADP (CV -0.98; 95% CI: -1.88, -0.08; p = 0.031) and resistin (CV -0.95; 95% CI: -1.83, -0.07; p = 0.034) levels decreased 120 minutes after treatment as compared with pretreatment. In addition, in responders, the HMW:T-ADP ratio (CV -0.04; 95% CI: -0.07, -0.01; p = 0.041) decreased and the LMW:T-ADP ratio (CV 0.04; 95% CI: 0.01, 0.07; p = 0.043) increased at 120 minutes after treatment. In nonresponders, the LMW:T-ADP ratio (CV -0.04; 95% CI: -0.07, -0.01; p = 0.018) decreased 120 minutes after treatment. Leptin was not associated with treatment response.

CONCLUSIONS

Both pretreatment migraine pain severity and treatment response are associated with changes in adipokine levels. Adipokines represent potential novel migraine biomarkers and drug targets.

Obesity and headache: part I--a systematic review of the epidemiology of obesity and headache

Individually, both obesity and headache are conditions associated with a substantial personal and societal impact. Recent data support that obesity is comorbid with headache in general and migraine specifically, as well as with certain secondary headache conditions such as idiopathic intracranial hypertension. In the current manuscript, we first briefly review the epidemiology of obesity and common primary and secondary headache disorders individually. This is followed by a systematic review of the general population data evaluating the association between obesity and headache in general, and then obesity and migraine and tension-type headache disorders. Finally, we briefly discuss the data on the association between obesity and a common secondary headache disorder that is associated with obesity, idiopathic intracranial hypertension. Taken together, these data suggest that it is important for clinicians and patients to be aware of the headache/migraine-obesity association, given that it is potentially modifiable. Hypotheses for mechanisms of the obesity-migraine association and treatment considerations for overweight and obese headache sufferers are discussed in the companion manuscript, as part II of this topic.

Midlife migraine and late-life parkinsonism: AGES-Reykjavik study

OBJECTIVE

In the present study, we tested the hypothesis that having migraine in middle age is related to late-life parkinsonism and a related disorder, restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED).

METHODS

The AGES-Reykjavik cohort (born 1907-1935) has been followed since 1967. Headaches were classified based on symptoms assessed in middle age. From 2002 to 2006, 5,764 participants were reexamined to assess symptoms of parkinsonism, diagnosis of Parkinson disease (PD), family history of PD, and RLS/WED.

RESULTS

Subjects with midlife migraine, particularly migraine with aura (MA), were in later life more likely than others to report parkinsonian symptoms (odds ratio [OR]MA = 3.6 [95% CI 2.7-4.8]) and diagnosed PD (ORMA = 2.5 [95% CI 1.2-5.2]). Women with MA were more likely than others to have a parent (ORMA = 2.26 [95% CI 1.3-4.0]) or sibling (ORMA = 1.78 [95% CI 1.1-2.9]) with PD. Late-life RLS/WED was increased for headache generally. Associations were independent of cardiovascular disease and MRI-evident presumed ischemic lesions.

CONCLUSIONS

These findings suggest there may be a common vulnerability to, or consequences of, migraine and multiple indicators of parkinsonism. Additional genetic and longitudinal observational studies are needed to identify candidate pathways that may account for the comorbid constellation of symptoms.

Obesity and headache: Part II--potential mechanism and treatment considerations

Obesity and headache are both associated with a substantial personal and societal impact, and epidemiologic studies have consistently identified a positive association between obesity and headache in general, as well as obesity and migraine specifically (see part I). In the current manuscript, we will discuss the potential mechanisms for the migraine-obesity association, with a focus on the central and peripheral pathophysiological pathways which overlap between migraine and those modulating the drive to feed. We then discuss surgical, behavioral, and pharmacological treatment considerations for overweight and obese migraineurs as well as for those with idiopathic intracranial hypertension. We close by briefly discussing where future research may be headed in light of this data.

The methodology of population surveys of headache prevalence, burden and cost: principles and recommendations from the Global Campaign against Headache

The global burden of headache is very large, but knowledge of it is far from complete and needs still to be gathered. Published population-based studies have used variable methodology, which has influenced findings and made comparisons difficult. Among the initiatives of the Global Campaign against Headache to improve and standardize methods in use for cross-sectional studies, the most important is the production of consensus-based methodological guidelines. This report describes the development of detailed principles and recommendations. For this purpose we brought together an expert consensus group to include experience and competence in headache epidemiology and/or epidemiology in general and drawn from all six WHO world regions. The recommendations presented are for anyone, of whatever background, with interests in designing, performing, understanding or assessing studies that measure or describe the burden of headache in populations. While aimed principally at researchers whose main interests are in the field of headache, they should also be useful, at least in parts, to those who are expert in public health or epidemiology and wish to extend their interest into the field of headache disorders. Most of all, these recommendations seek to encourage collaborations between specialists in headache disorders and epidemiologists. The focus is on migraine, tension-type headache and medication-overuse headache, but they are not intended to be exclusive to these. The burdens arising from secondary headaches are, in the majority of cases, more correctly attributed to the underlying disorders. Nevertheless, the principles outlined here are relevant for epidemiological studies on secondary headaches, provided that adequate definitions can be not only given but also applied in questionnaires or other survey instruments.

Diagnosis, prevalence estimation and burden measurement in population surveys of headache: presenting the HARDSHIP questionnaire

The global burden of headache is very large, but knowledge of it is far from complete and needs still to be gathered. Published population-based studies have used variable methodology, which has influenced findings and made comparisons difficult. The Global Campaign against Headache is undertaking initiatives to improve and standardize methods in use for cross-sectional studies. One requirement is for a survey instrument with proven cross-cultural validity. This report describes the development of such an instrument. Two of the authors developed the initial version, which was used with adaptations in population-based studies in China, Ethiopia, India, Nepal, Pakistan, Russia, Saudi Arabia, Zambia and 10 countries in the European Union. The resultant evolution of this instrument was reviewed by an expert consensus group drawn from all world regions. The final output was the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) questionnaire, designed for application by trained lay interviewers. HARDSHIP is a modular instrument incorporating demographic enquiry, diagnostic questions based on ICHD-3 beta criteria, and enquiries into each of the following as components of headache-attributed burden: symptom burden; health-care utilization; disability and productive time losses; impact on education, career and earnings; perception of control; interictal burden; overall individual burden; effects on relationships and family dynamics; effects on others, including household partner and children; quality of life; wellbeing; obesity as a comorbidity. HARDSHIP already has demonstrated validity and acceptability in multiple languages and cultures. Modules may be included or not, and others (eg, on additional comorbidities) added, according to the purpose of the study and resources (especially time) available.

Improving quality in population surveys of headache prevalence, burden and cost: key methodological considerations

Population-based studies of headache disorders are important. They inform needs assessment and underpin service policy for a set of disorders that are a public-health priority. On the one hand, our knowledge of the global burden of headache is incomplete, with major geographical gaps; on the other, methodological differences and variable quality are notable among published studies of headache prevalence, burden and cost. The purpose here was to start the process of developing standardized and better methodology in these studies. An expert consensus group was assembled to identify the key methodological issues, and areas where studies might fail. Members had competence and practical experience in headache epidemiology or epidemiology in general, and were drawn from all WHO world regions. We reviewed the relevant literature, and supplemented the knowledge gathered from this exercise with experience gained from recent Global Campaign population-based studies, not all yet published. We extracted methodological themes and identified issues within them that were of key importance. We found wide variations in methodology. The themes within which methodological shortcomings had adverse impact on quality were the following: study design; selection and/or definition of population of interest; sampling and bias avoidance; sample size estimation; access to selected subjects (managing and reporting non-participation); case definition (including diagnosis and timeframe); case ascertainment (including diagnostic validation of questionnaires); burden estimation; reporting (methods and results). These are discussed.

Migraine and the social selection vs causation hypotheses: a question larger than either/or?

For decades, the question of social selection vs social causation has been raised by public health researchers and social scientists to explain the association between socioeconomic factors and mood disorders.(1,2) The social selection or "downward drift" theory postulates that the disease itself limits an individual's educational and occupational achievements, leading to a lower socioeconomic status (SES). In contrast, the social causation hypothesis suggests that factors associated with low SES (e.g., stressful life events, poor health care access) increase the likelihood of disease onset or prolonged disease duration.(3,4) Simply stated, the end result of each hypothesis is as follows:

Migraine, depression, and brain volume: the AGES-Reykjavik Study

OBJECTIVE

To examine the joint association of migraine headache and major depressive disorder on brain volume in older persons without dementia.

METHODS

Participants (n = 4,296, 58% women) from the population-based Age, Gene/Environment Susceptibility-Reykjavik Study were assessed for migraine headache in 1967-1991 (age 51 years [range 33-65]) according to modified International Classification of Headache Disorders-II criteria. In 2002-2006 (age 76 years [range 66-96]), lifetime history of major depressive disorder (depression) was diagnosed according to DSM-IV criteria, and full-brain MRI was acquired, which was computer postprocessed into total brain volume (TBV) (gray matter [GM], white matter [WM], white matter hyperintensities) and CSF volume for each study subject. We compared brain tissue volumes by headache categories with or without depression using linear regression, adjusting for intracranial volume and other factors.

RESULTS

Compared with the reference group (no headache, no depression) TBV and WM and GM volumes were smaller in those with both migraine and depression (TBV -19.2 mL, 95% confidence interval [CI] -35.3, -3.1, p = 0.02; WM -12.8 mL, CI -21.3, -4.3, p = 0.003; GM -13.0 mL, CI -26.0, 0.1, p = 0.05) but not for those with migraine alone (TBV 0.4 mL, WM 0.2 mL, GM 0.6 mL) or depression alone (TBV -3.9 mL, WM -0.9 mL, GM -2.9 mL).

CONCLUSIONS

Reporting both migraine and major depressive disorder was associated with smaller brain tissue volumes than having one or neither of these conditions. Migraineurs with depression may represent a distinct clinical phenotype with different long-term sequelae. Nonetheless, the number of subjects in the current study is relatively small and these findings need to be confirmed in future studies.