Healthcare resource use and costs associated with the misdiagnosis of migraine

OBJECTIVE: To compare healthcare resource utilization and healthcare costs in patients with migraine with or without a history of misdiagnosis. BACKGROUND: Despite the high prevalence of migraine, migraine is commonly misdiagnosed. The healthcare resource use and cost burden of a misdiagnosis is unknown. METHODS: This retrospective cohort study identified adults with an incident migraine diagnosis from the Merative™ Marketscan® Commercial and Medicare Supplemental Databases between June 2018 and 2019. Patients with a diagnosis of commonly considered misdiagnoses (headache, sinusitis, or cervical pain) before their migraine diagnosis were classified as the "misdiagnosed cohort." Patients in the misdiagnosed cohort were potentially misdiagnosed, then eventually received a correct diagnosis. Patients without a history of commonly considered misdiagnoses prior to their migraine diagnosis were classified as the "correctly diagnosed cohort." Healthcare resource utilization and healthcare costs were assessed in the period before migraine diagnosis and compared between the cohorts. Outcomes were reported as per patient per month and compared with incidence rate ratios. RESULTS: A total of 29,147 patients comprised the correctly diagnosed cohort and 3841 patients comprised the misdiagnosed cohort and met the inclusion criteria. Patients in the misdiagnosed cohort had statistically significantly higher rates of inpatient admissions (0.02 vs. 0.01, incidence rate ratio [IRR] 1.61, 95% confidence interval [CI] 1.47-1.74), emergency department visits (0.10 vs. 0.05; IRR 1.89, 95% CI 1.79-1.99), neurologist visits (0.12 vs. 0.02; IRR 5.95, 95% CI 5.40-6.57), non-neurologist outpatient visits (2.64 vs. 1.58; IRR 1.67, 95% CI 1.62-1.72) and prescription fills (2.82 vs. 1.84; IRR 1.53, 95% CI 1.48-1.58) compared to correctly diagnosed patients. Misdiagnosed patients had statistically significantly higher rates of healthcare cost accrual for inpatient admissions ($1362 vs. $518; IRR 2.62, 95% CI 2.50-2.75), emergency department visits ($222 vs. $98; IRR 2.27, 95% CI 2.18-2.36), neurologist visits ($42 vs. $9; IRR 4.39, 95% CI 4.00-4.79), non-neurologist outpatient visits ($1327 vs. $641; IRR 2.07, 95% CI 1.91-2.24), and prescription fills ($305 vs. $215; IRR 1.41, 95% CI 1.18-1.70) compared to correctly diagnosed patients. CONCLUSION: Patients with migraine who have a history of misdiagnoses have higher rates of healthcare resource utilization and cost accrual versus those without such history.