Survey of self-awareness and behavior in Japanese with depressive features: Importance of early diagnosis and treatment by primary care physicians

Background: Many "hidden" patients who are actually in a depressive state remain undiagnosed and untreated in Japan. Early detection and treatment for these "hidden" patients by primary care physicians is desirable, but this remains a major challenge for the Japanese medical community. Objective: To improve the understanding of characteristics and general behavior in patients with "hidden" depression who showed depressive tendencies on a two-question depression screen. Methods: In February 2016, we surveyed the incidence rate and extent of hidden depression by conducting a web-based questionnaire in men and women between 20 and 70 years of age across Japan. Results: In the incidence rate survey, 39% of the 19,975 respondents were judged to have "depressive tendencies." Many of those patients suffered from psychosomatic disorders. Among the responders who were considered to have "depressive tendencies," 91.9% had not been diagnosed with depression or depressive state. However, 43.6% were under a physician's care, either through a department of internal medicine or theclinic of a primary care physician. Of the 2028 patients who responded to the hidden depression survey, 43.5% had only discussed their psychosomatic disorders with a neighborhood primary care physician. Conclusion: In Japan, many who have depressive tendencies have not been diagnosed as being in a depressive state, and about 40% have consulted only with a neighborhood primary care physician about their disorders.