title: Risk of Headache-Related Healthcare Visits in Patients With Celiac Disease: A Population-Based Observational Study.
abstract: OBJECTIVE
  Patients with celiac disease (CD) are reported to be at increased risk for headaches, though large studies are lacking. We aimed to examine the risk of headache-related healthcare encounters in patients with CD in a nationwide population-based setting.
  
  
  METHODS
  In this population-based retrospective cohort study, we searched all (n = 28) pathology departments in Sweden and identified patients with CD based on the presence of villous atrophy (VA). Each patient was matched to up to 5 controls, by age, gender, calendar period, and region. Using Cox proportional hazards, we tested for an association between CD and subsequent headache-related visit. We also tested this association for those with intestinal inflammation but normal villi, and subjects with positive CD serologies but normal histology.
  
  
  RESULTS
  Among 28,638 patients with CD and 143,126 controls, headache-related visit occurred in 1,337 (4.7%) and 4,102 (2.9%), respectively. The incidence of headache-related visit was 423 per 100,000 person-years in CD patients and 254 per 100,000 person-years in controls (HR 1.66; 95% CI 1.56-1.77; P < .0001). Individuals having inflammation without VA on small intestinal biopsy (n = 12,898; HR 2.08; 95% CI 1.90-2.27; P < .0001) and those with normal mucosa but positive CD serology (n = 3,617; HR 1.83; 95% CI 1.57-2.12; P < .0001) were also at increased risk for headache-related visit.
  
  
  CONCLUSIONS
  In this population-based study we found a significantly increased risk of headache-related visits in patients with CD; this increase was also present in patients with intestinal inflammation and those with positive CD serology but with normal mucosal architecture on small bowel biopsy. Though limited by surveillance bias, this study indicates that headache-related visits are more common in these populations.
authors.affiliation: Department of Medicine, Celiac Disease Center, Columbia University College of Physicians and Surgeons, New York, NY, USA.|Department of Medical Epidemiology and Biostatistics, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.|Department of Epidemiology, Mailman School of Public Health, Columbia University Medical Center, New York, NY, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Lebwohl
authors.forename: Abhik
authors.initials: A
authors.lastname: Roy
authors.affiliation: Department of Medicine, Celiac Disease Center, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Armin
authors.initials: A
authors.lastname: Alaedini
authors.affiliation: Department of Medicine, Celiac Disease Center, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Peter H R
authors.initials: PHR
authors.lastname: Green
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.|Department of Pediatrics, Örebro University Hospital, Sweden.
authors.forename: Jonas F
authors.initials: JF
authors.lastname: Ludvigsson
keywords: celiac disease; epidemiology; headache