Abstract
AIMS: The aim of this article is to determine the patient-level factors associated with headache neuroimaging in outpatient practice. METHODS: Using data from the 2007-2010 National Ambulatory Medical Care Surveys (NAMCS), we estimated headache neuroimaging utilization (cross-sectional). Multivariable logistic regression was used to explore associations between patient-level factors and neuroimaging utilization. A Markov model with Monte Carlo simulation was used to estimate neuroimaging utilization over time at the individual patient level. RESULTS: Migraine diagnoses (OR = 0.6, 95% CI 0.4-0.9) and chronic headaches (routine, chronic OR = 0.3, 95% CI 0.2-0.6; flare-up, chronic OR = 0.5, 95% CI 0.3-0.96) were associated with lower utilization, but even in these populations neuroimaging was ordered frequently. Red flags for intracranial pathology did not increase use of neuroimaging studies (OR = 1.4, 95% CI 0.95-2.2). Neurologist visits (OR = 1.7, 95% CI 0.99-2.9) and first visits to a practice (OR = 3.2, 95% CI 1.4-7.4) were associated with increased imaging. A patient with new migraine headaches has a 39% (95% CI 24-54%) chance of receiving a neuroimaging study after five years and a patient with a flare-up of chronic headaches has a 51% (32-68%) chance. CONCLUSIONS: Neuroimaging is routinely ordered in outpatient headache patients including populations where guidelines specifically recommend against their use (migraines, chronic headaches, no red flags).