A retrospective matched case-control study on medical costs of refractory migraine in Taiwan.

BACKGROUND

Migraine is associated with a significant economic burden in Western countries. However, there is limited information regarding the impact of the cost of migraine in Asia.

OBJECTIVES

To quantify and compare the direct medical costs of refractory migraine (RM) and other migraine, using health insurance claims data in Taiwan.

METHODS

A retrospective matched case-control study was conducted utilizing data from the Taiwan National Health Insurance Research Database. RM cases were defined as patients with at least 1 neurological outpatient visit with a primary or secondary International Classification of Diseases, Ninth Revision, Clinical Modification code of 346.11 (common migraine with intractable migraine, so stated), diagnosed by certified neurologists in medical centers during 2007-2008. The first control group was the non-migraineurs matched with cases at a 4:1 ratio by age, gender, urbanization level of the residence, and income. The second control group was patients with other migraine types (346.00, 346.10, 346.20, 346.80, and 346.90) matched with cases at a 4:1 ratio by age, gender, and hospital setting. Medical utilization and costs within 365 days after the index visit date were assessed using a 2-part model. The exchange rate for US $1 was NT $32.50.

RESULTS

Patients with RM had significantly higher total medical costs compared with non-migraineurs (NT $57,932 [US $1783] vs. NT $26,817 [US $825]; P < .001) or other migraineurs (NT $54,678 [US $1682] vs. NT $38,397 [US $1181]; P < .001). The mean drug costs for those with RM were also higher than for non-migraineurs (NT $19,752 [US$608] vs. NT $8660 [US $266]; P < .001) or those with other migraine (NT $17,623 [US $542] vs. NT $10,088 [US $310]; P < .001). In addition, we reviewed the charts of all patients with an outpatient department diagnostic code of 346.11 (n = 98) at our hospital (Taipei Veterans General Hospital, a medical center in Taiwan) in 2007. Of these patients, 88 (90%) fulfilled the Silberstein-Lipton criteria for chronic migraine, i.e., >15 headache days per month and presence of a history of migraine.

CONCLUSIONS

Refractory migraineurs in Taiwan had significantly higher medical costs than either non-migraineurs or those with other migraine diagnoses.