Characteristics in patients with headache in an outpatient clinic in Japan.

Background: Little is known about the prevalence of primary and secondary headache in clinics in Japan. The aim of this study is to characterize patients with headache in an outpatient unit where primary care physicians are working in Japan.

Methods: Consecutive outpatients who newly visited the Department of General Medicine, Asahikawa Medical College Hospital, Asahikawa, Japan between April 2005 and March 2009 were analyzed. Each parameter such as age, sex or diagnosis was investigated.

Results: Out of 4693 patients, 418 patients visited to our department because of headache. Primary headache was found in 167 patients (39.9%). The rate of tension-type headache (TTH) (30.8%) was highest, followed by migraine (9.1%). Approximately 3 times higher rate of migraine was observed in female patients when compared with male patients. In female patients, migraine was observed more frequently in younger patients. On the other hands, TTH was observed in almost all aged patients in males and females, and the rate of TTH peaks between the ages of 40 and 49 years in both sex. The present study also demonstrated that 8.4% of patients who chiefly complained of headache had been diagnosed as depression while 1.7% of remained patients had been diagnosed as depression, indicating 5-times higher rate of depression in patients with headache.

Conclusion: All these results suggest that primary headache, especially TTH, is highly observed and depression should be considered in patients with headache in an outpatient clinic where primary care physicians are working in Japan.