Hikikomori, COVID-19 andNovel Therapeutic Approach

Takahiro A. Kato, MD, PhD
Associate Professor
Mood Disorder / Hikikomori Clinic, Kyushu University Hospital &Department of Neuropsychiatry, Graduate school of Medical Sciences,
Kyushu University, Fukuoka, Japan

Today’s Topic• What is Hikikomori– Japan and Worldwide– COVID-19• Understanding Hikikomori (Hikikomori Research Clinic)– Psychological, Sociocultural and Biological Aspects• Intervention of Hikikomori–––

Step by Step Approach (Multi-dementional Model)
Family Intervention (MHFA-based)
Novel approach (Animals, Robots and Avatars)

The casual Japanese word “Hikikomoru-ひきこもる” has been used to describe the behavior
and/or condition of shut-ins from non-pathological to severe pathological state since 1970s.
Dr. Tamaki Saito initially used the word “Hikikomori-ひきこもり” in 1998.

Listed in Oxford Dictionaries Since October 2010

How common is hikikomori in Japan?
Psychiatry Research 176 (2010) 69–74

Contents lists available at ScienceDirect

Psychiatry Researchj o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / p s yc h r e s

Lifetime prevalence, psychiatric comorbidity and demographic correlates of“hikikomori” in a community population in Japan
Asuka Koyama a,⁎, Yuko Miyake a, Norito Kawakami b, Masao Tsuchiya b,c,Hisateru Tachimori a, Tadashi Takeshima a
The World Mental Health Japan Survey Group, 2002–2006a

National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Japan
Department of Mental Health, Graduate School of Medicine, the University of Tokyo, Tokyo, JapancHygiene and Preventive Medicine, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japanba r t i c l ei n f oArticle history:
Received 29 January 2008
Received in revised form 13 August 2008
Accepted 23 October 2008
Keywords:
Epidemiology
JapanPsychopathology
Social withdrawal

a b s t r a c t

1.2%

The epidemiology of “hikikomori” (acute social withdrawal) in a community population is not clear,although it has been noted for the past decade in Japan. The objective of this study is to clarify theprevalence of “hikikomori” and to examine the relation between “hikikomori” and psychiatric disorders. A
face-to-face household survey was conducted of community residents (n = 4134). We deﬁned “hikikomori”
as a psychopathological phenomenon in which people become completely withdrawn from society for6 months or longer. We asked all respondents whether they had any children currently experiencing“hikikomori”. For respondents aged 20–49 years old (n = 1660), we asked whether they had everexperienced “hikikomori”. A total of 1.2% had experienced “hikikomori” in their lifetime. Among them,
54.5% had also experienced a psychiatric (mood, anxiety, impulse control, or substance-related) disorder intheir lifetime. Respondents who experienced “hikikomori” had a 6.1 times higher risk of mood disorder.
Among respondents, 0.5% currently had at least one child who had experienced “hikikomori”. The study
suggests that “hikikomori” is common in the community population in Japan. While psychiatric disorders
were often comorbid with “hikikomori”, half of the cases seem to be “primary hikikomori” without acomorbid psychiatric disorder.
© 2008 Elsevier Ireland Ltd. All rights reserved.

(232,000?)

Koyama A et al. Lifetime prevalence, psychiatric comorbidity and demographic correlates of “hikikomori” in acommunity population in Japan. Psychiatry Research, 2010;176(1);69-74

Age 15-39
Japan’s Cabinet Office Report 2016

Onset age of Hikikomori(15-39 y.o.)
540,000+(40-59 y.o.)610,000

1,150,000

The “8050 problem”
Individuals with hikikomori in their 50s living alone
with parents who are in their 80s(Japan times, 1 June 2019)

IsHikikomori
only in JAPAN?

Hypothesis Paper to Spread Hikikomori Worldwide
ひきこもりが世界拡大することを予測（Kato Lancet 2011)(Kato*, Shinfuku, Sartorius & Kanba, Lancet 2011)

「病的ひきこもり」が国外にも存在する初の実証研究

How common is hikikomori in Hong Kong?
(Telephone Interview)

1.9%
17,000 –41,000
Wong W et al. (2014). Int J Soc Psychiatry

Hikikomori in the Mainland China (SNS survey)

Wong et al. 2017
Liu et a. 2018

Is hikikomori global?

(Wu et al. Lancet Psychiatry 2019)九州大学病院
精神科神経科
ひきこもり外来
Hikikomori Research Clinic
Kyushu University Hospital
Fukuoka, Japan

Clinical and Research trial
against Hikikomori/MTDin Kyushu Univ. (Fukuoka, Japan)
・Clarifying the biopsychosocial cause
・Development of evaluation tools(psychometrics and PC-oriented games)
・Intervention Tool Development(Group psychotherapy, etc..)

Hikikomori supports/intervention/research network
in Fukuoka, Japan

ひきこもり専門相談室（月1回金曜）Kato visits Hikikomori
support center
once a month

Recruitment
Assessment
Feedback

Hikikomori Line (Phone)
Web, e-mailParents’ actions

Individual counselingGroup activities
Parents’ supports
Job supports, etc..
More than 100 cases
introduced

Kyushu University Hospital（Kato’s Hikikomori Clinic)世界初・九州⼤学病院「ひきこもり」研究外来での活動概要

ひきこもりは世界的に深刻な問題
世界初の国際HIKIKOMORIコンソーシアム会議 主催（２０２１年２月６日WEB）国際連携の重要性を認識

Kato et al. Lancet 2011
ひきこもりが世界中に拡がっていくことに警鐘（ひきこもりの国際化を予測）

Lancet Psychiatry
2018 Jan
九大病院専門外来がハイライトに紹介された

Kato, et al.

Am J Psychiatry
2016 Feb

甘え・高齢化8050問題への対応提案

Kato, et al. World Psychiatry 2020

九大発 診断法を国際標準として提案

Strengthening the prevention/support system
for Hikikomori is essential
in the COVID-19 era

COVID-19 may cause an explosion of Hikikomori globally.
（Kato TA, Sartorius N, Shinfuku N. Psychiatry Clin Neurosci 2020 July)

The vicious cycle of anxiety, depression, loneliness, and hikikomori
SchoolWork
Disaster
COVID-19

StressfulLife-events

Adversity experience
During developmental periods

Self-Help Behaviors

Hikikomori
Increasedloneliness

Decrease in directinterpersonal interaction

Decrease ofGoing Out

OnlineGames
Alcohol
Drugs

Addiction

COVID-19

PathologicalAddiction(Kato “Minna no Hikikomori” 2020: Curr Opin Psychiatry 2020, PCN 2020)

Violence, abuse, suicide, etc.

Smart
PhoneSTAY
HOME

Anxiety
Depression

Internet

Laptopcomputer

COVID-19

Do individuals with hikikomori
have mental disorders?

Results: Most Common SCID-I
and SCID-II Diagnoses

Diagnosis

Total
N=22%

Avoidant Personality Disorder941%

Major Depressive Disorder732%

Paranoid Personality Disorder

732%

Social Anxiety Disorder627%

Posttraumatic Stress Disorder627%

5 hikikomori persons (22%) only in Japan have no psychiatric diagnosis!!!
Teo AR et al. Psychopathology associated with social withdrawal. Psychiatry Research 2015

Modern-Type depression(MTD)
among youth
may be a“GATEWAY Disorder”
toward Hikikomori.

Kato & Kanba, Am J Psychiatry 2017 November issue

Hikikomori

Modern Depression

ProlongedSocial
Avoidance

Depressed Feelings
Only At School/Workplaces(Kato & Kanba, Am J Psychiatry, 2017 Nov & 2018 May)

Location of Hikikomori in Psychiatryialc
So ietyxAnHallucination

Schizophrenia
Psychosis

HikikomoriCondition

Interdependent Society (Amae)
Weaker Paternal Value
Strong Mother-Child Relationship

Psychological PainPT
Tra SDuma

Avoidant
Narcissistic
Schizoidtyilna erosr ordAnhedoniae
P D isLoss of Motivation
Suicidal Ideation

Depression

Inflammation
Oxidative Stress
Microglia, etc…

InternetIT-Society
artificial intelligence (A.I.)
COVID-19

Kato et al. PCN 2019

SocioCulturalFactorsoFa logct icaor ls

ASpe utisticDis ctrum
orderDelusion

Loneliness
Shame (Haji)
Lower Trust
Lower Self-Esteem

Anxiety
Fear
PhobiaEscapeBi

Problems in
Social Communication& Social Interaction

alg iclo s
h o oryc ct
Ps Fa

Non-Psychiatric State

Psychiatric State(Bio-Psycho-Socio-Cultural Model)

Biological Aspects ofHikikomoriǤǤ Ȁ  

Received: 27 November 2017
Accepted: 31 January 2018
Published: xx xx xxxx

Blood biomarkers of Hikikomori, asevere social withdrawal syndrome
Kohei Hayakawaͷ, Takahiro A. Kato ͷ, Motoki Watabe ͸, Alan R. Teo͹ǡͺ, Hideki Horikawaͷ,Nobuki Kuwanoͷ, Norihiro Shimokawaͷ, Mina Sato-Kasaiͷ, Hiroaki Kuboͷ, Masahiro Ohgidaniͷ,
Noriaki Sagataͷ, Hiroyuki Todaͻ, Masaru Tatenoͼ, Naotaka Shinfukuͽ, Junji Kishimoto; &Shigenobu Kanbaͷ
Hikikomori, a severe form of social withdrawal syndrome, is a growing social issue in Japan andǤ ơ 
treatment remains to be established. Recently, we revealed that avoidant personality disorder is themost common comorbidity of hikikomori. Thus, we have postulated that avoidant personality is thepersonality underpinning hikikomori. First, we herein show relationships between avoidant personality
traits, blood biomarkers, hikikomori-related psychological features, and behavioural characteristics
assessed by a trust game in non-hikikomori volunteers. Avoidant personality traits were negatively
associated with high-density lipoprotein cholesterol (HDL-C) and uric acid (UA) in men, and positively Ƥ ȋ ȌǦ ȋȌwomen. Next, we recruited actual individuals with hikikomori, and compared avoidant personalitytraits, blood biomarkers, and psychological features between individuals with hikikomori and agematched healthy controls. Individuals with hikikomori had higher avoidant personality scores in bothsexes, and showed lower serum UA levels in men and lower HDL-C levels in women compared with ǤƤǡ
the door to clarify the underlying biological pathophysiology of hikikomori.

ひきこもり者の初の生物学的エビデンス“Hikikomori”, a severe form of social withdrawal seen more often in individuals of relatively young age, has
become a growing social issue since around 1990 in Japan1–4. Hikikomori is usually defined as follows: (i) spending most of the day and nearly every day at home, (ii) avoiding social situations such as attending school or work-

Uric Acid (UA) and HDL-C (Possible Biomarkers of Hikikomori)FemaleHealthy Volunteers vs Hikikomorib. 女性

Malea. 男性
Healthy Volunteers vs Hikikomori
Serum Uric Acid（P<0.001）

Serum HDL-Cholesterol（p=0.011）
150

106HDL-C

尿酸84100

5020『ひきこもり』群Hikikomori（n=24）

健常対照群
HC（n=34）

0『ひきこもり』群Hikikomori

健常対照群
HC（n=18）（n=44）(Hayakawa, Kato* et al. Scientific Reports 2018)

Intervention of Hikikomori

Huge GAP
between
Sufferers and Support Centers
Hikikomori Support Centers
Hospitals / Clinics

Hikikomori Support is Very Difficult!!
•Average of “Start support” after the onset ofhikikomori is about 4.4 years. (Kondo, et al. 2010)•Thus, the Japan’s Cabinet Office’s Guideline ofHikikomori (2010) empathized the importance of
Early Detection and Early Intervention ofHikikomori.
Each hikikomori support center (more than 60centers in each prefecture and main larger cities inJapan) have tried to develop the system, usingphone counseling (HIKIKOMORI LIFE LINE), etc.

•No standardized intervention methods have been developed.

Step-By-Step therapeutic approaches
against hikikomori④ Participating Society
その人なりの社会参加を目指す。

段階的就労支援等③ Group Approach
家庭以外で、安心できる場を得る。社会体験を積む。

居場所支援、社会体験活動② Individual Approach
家族以外の人（相談員等）との関係構築。

本人の個別相談① Family Approach (Especially, for Parents)
家族だけで抱え込まない。適切な対応方法を知る。

家族相談、家族教室への参加、家族会への参加
Modified from the Hikikomori Guideline published by Japan’s Governmental Office 2010

ひきこもり家族支援プログラム開発Development ofEducational/Training Programfor Parents of Hikikomori
based onMHFA (Mental Health First Aid)

国立研究開発法人日本医療研究開発機構（AMED）・障害者対策総合研究開発事業「社会的ひきこもりの長期化打開のためのエビデンスに基づく家族向け教育支援モデルの構築」

Development of Educational/Training Programfor Parents of Hikikomori
based onMHFA (Mental Health First Aid)
@ Kyushu University Hospital
Funded by AMED, Japan

Multidimensional Therapeutic Approaches
Based on the Physical/Social Situation of Hikikomori

On-Site Interventions
・Physicians (i.e. Psychiatrists)
・Clinical Psychologists
・Social workers
・Nurses・Other specialists
Home Visit
・Physicians
・Psychologists・Social workers
・Nurses・Other specialists
Family Interventions
・Psychoeducation
・Mental Health First Aid(MHFA)･ Community
Reinforcement andFamily Training (CRAFT)(X)
Living withpersons mainly
family members(Y)
Living alone[Stage 1X][Stage 1Y]

Sometimes leaves own homeand/orSome direct interaction withothers outside (2-3 days/weeks)

Lives alone andsome direct interaction
with others outside[Stage 2X][Stage 2Y]

Rarely leaves own home andmostly does not interact
directly with others outside
but some direct communication
with cohabitating persons(2-3 days/weeks)

Lives alone and mostly
does not interact directlywith others outside(1 day/week or less)(1 day/week or less)[Stage 3X]

Rarely leaves own room andrejects cohabitating persons(1 day/week or less)

Stratification of Individuals with Hikikomori

Internet Interventions
・Web-based therapies(Telepsychiatry medicine)・Location-based
augmented reality tools
Non-Human Interventions
・Animals (Dogs, Cats, etc…)
・Robots
Home Visit
・Physicians
・Psychologists
・Social workers
・Nurses・Other specialists

Innovative Approachagainst HikikomoriDogs and/or Cats rescue individuals with hikikomori?

(This project has been organized by Prof. Paul Wai-Ching WONG.)

Can Robots rescue
shut-ins?

OriHimeView from the Eye of OriHime (iPhone, iPad and online PC)
1. Not observed/seen from others (Shadowing)
2. Verbal Communication with Mic
3. Non-Verbal Communication with Buttons
Yoshikawa, Kumazaki, Kato: Curr Opin Psychiatry 2021 (in press)

Metaverse (avatars) rescue hikikomori?
CNA

CNA

Prof. Hayashi(Yamaguchi University)

Metaverse Project (Fukuoka-Prefecture)
JACFA-Job Support Station (Directors: Ms Michiko Asami/Ms Kumiko Asami)
Yamaguchi University (Prof. Yuko Hayashi)
Digital Hollywood University (Prof. Keiji Mitsubuchi)
Kyushu University (Takahiro A. Kato)

Possible solution against Shame (恥） with persons with hikikomori

Summary• What is Hikikomori– Japan and Worldwide• Understanding Hikikomori (Hikikomori Research Clinic)– Psychological, Sociocultural and Biological Aspects• Intervention of Hikikomori–––

Step by Step Approach (Multi-dementional Model)
Family Intervention (MHFA-based)
Novel approach (Robots and Avatars)

https://www.hikikomori-lab.com/(Minna no Hikikomori, 2021)