Hikikomori, i. e., severe social withdrawal, has been an emerging mental health concern among adolescents and young adults over the last two decades in Japan, warranting an array of community support and mental health services. As the specialized agency of health promotion in the community, public health centers (PHCs) have an important role of service provision for hikikomori individuals in cooperation with mental health and welfare centers (MHWCs). However, many challenges in the community care system for hikikomori remain. To investigate service provision for hikikomori individuals, a questionnaire survey was conducted for PHCs. Of 485 PHCs across the country, 353 responded(the response rate was 72.8%). Approximately 90% of the PHCs were involved in consultation for hikikomori and half provided continuing services. Nearly 20% of PHCs had seminars or lectures, and one―third organized family classes/meetings to address hikikomori support services. In terms of the necessity of hikikomori support by PHCs, most PHCs responded "necessary" or "somewhat necessary". Challenges for effective service provision were a shortage of staff, professional expertise, and social services, suggesting that more staff and resources are needed. Many MHCs collaborated with local authorities, medical institutions, and MHWCs. Regarding MHWCs, the staff of PHCs participated in the meetings, seminars, or case conferences at MHWCs and gave referrals to MHWCs. The most common concerns about hikikomori individuals were family violence/troubles, medical judgment, future life/finances, uncertainty of life after the death of parents, difficulties in providing services to the family members, lack of a secure place, and increases in elderly hikikomori individuals. Furthermore, there were many cases in which some clinical features of neurodevelopmental disorders were present. In order to effectively support hikikomori, it is necessary to utilize different programs or measures and collaborate with relevant organizations. The future community mental health care system aims to establish a comprehensive community care system including mental disorders. Within this system, PHCs are expected to respond to the most difficult hikikomori cases and coordinate relevant organizations in the community.
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