Hikikomori and the COVID-19 pandemic: not leaving behind the socially withdrawn

The coronavirus disease 2019 (COVID-19) pandemic, which started in China in December 2019 and rapidly spread worldwide, has required most world leaders to take measures to contain and control the spread of the virus, including social distancing and mass quarantine.1 However, these interventions are likely to produce a considerable burden on the mental health of affected populations.2 In the past few months, teams of investigators have been joining efforts to arrive at a more comprehensive understanding of the mental health consequences of the COVID-19 outbreak. Nevertheless, it would be important to add discussion about the potential impact that such measures may have on the prevalence of a relatively new psychiatric disorder called hikikomori or “pathological social withdrawal.”

Hikikomori was initially reported in Japan in the 1990s and is described as a condition of prolonged and severe social withdrawal lasting for at least six months, apparently not better explained by co-occurring severe psychiatric disorders.3,4 In most cases, the affected individual, usually a young male, remains isolated in his own house, or in his own room in more severe cases.4 Although it was initially considered a Japanese cultural syndrome, over the years it has been reported in a variety of countries around the world, gaining the status of a public health problem in Asia, with prevalence estimates in community populations varying from 0.87 to 2.3%.3-5 Although it is not possible to make inferences about causality in hikikomori cases, it seems that technology and the Internet are associated with this diagnosis.4,6 Additionally, comorbid psychiatric conditions have been reported in many hikikomori cases, and these patients may be at increased suicide risk.4,6 Family interventions, comorbidity treatment, online interventions, physical activity, multiple psychotherapeutic approaches, social skills training, etc., have been indicated as potentially useful strategies for hikikomori cases.3,7-11 Nevertheless, the evidence to support these treatment approaches is weak, mainly due to a lack of studies on the topic.3,6

In 2020, updated diagnostic criteria4 were proposed for hikikomori, with the inclusion of a severity classification based on the weekly frequency the individual leaves his home or room. Physical isolation at home is regarded as the central characteristic of the syndrome, which can be diagnosed only when all the following criteria are met: “a) marked social isolation in one's home; b) duration of continuous social isolation of at least 6 months; c) significant functional impairment or distress associated with the social isolation.” Per definition, only individuals who leave home 3 or less days/week, for a prolonged period of time as stated above, can be defined as hikikomori. 4 Even though loneliness is not one of the mandatory diagnostic criteria of the syndrome, it is a characteristic that becomes more pronounced with increasing continuous social withdrawal.4,10

The prevalence of hikikomori in Brazil is unknown due to a lack of empirical research on the phenomenon; however, the syndrome has been reported three times in Brazilian patients.9,12,13 Recently, our group described the complete treatment program for one of these cases. The patient reported substantial clinical improvement after a multimodal intervention strategy, including pharmacological treatment of comorbidities, family psychoeducation, and the use of different psychotherapy techniques.9

Considering this scenario, we hypothesized that strict confinement measures may have relevant negative consequences on hikikomori cases, and the syndrome is likely to grow in prevalence. Young people, not only those with pathological social withdrawal, may increase the time spent gaming or on the Internet, factors potentially associated with the syndrome.4,6 In Italy, for instance, empirical data described an increase in the use of digital media near bedtime during the lockdown.14 Another important point of discussion is the expected increase of new technology-dependent habits during the COVID-19 pandemic that may persist in the aftermath of the pandemic, such as online shopping, food delivery, online education courses, exclusively online social interaction, and online medical and psychological appointments. Such life habits may be associated with hikikomori cases and could further increase their prevalence in the near future.6,8 The rise in prevalence of psychiatric symptoms and disorders also may result in more hikikomori cases. Studies from China highlighted a substantial increase in anxiety and depression15 during the COVID-19 outbreak, with a depression prevalence of 43.7% among Chinese adolescents.16

It is also necessary to assess how painful and emotionally distressing quarantine and social distancing measures are for hikikomori cases in comparison to other populations. Although it could be that populations that were socially withdrawn prior to the pandemic may not suffer as much, empirical data from Spain indicated loneliness as the strongest predictor of depression, PTSD and anxiety during the COVID-19 outbreak.17

Despite the lack of empirical data, families and health professionals should be vigilant about the potential increased risk of hikikomori among young people during and after the COVID-19 pandemic. Exercising at home, maintaining a healthy diet, and limiting screen time are all lifestyle behaviours that have been recommended during this pandemic18 and are likely to promote better mental health outcomes. They may also have a positive impact on individuals at risk for hikikomori. In addition, once the pandemic is over, parents could focus on fostering outdoor activities and face-to-face interaction.

Social isolation has been growing in prevalence over the past decades, which has led some authors to say that we have been facing a silent and rising epidemic, potentially associated with other serious contemporary epidemics such as suicide and opioid use, called the “modern behavioral epidemic of loneliness.”19 Hikikomori, likewise, could be considered a rising and silent epidemic during and in the aftermath of the COVID-19 pandemic, since physical and social isolation is likely to increase. Therefore, it is essential not to further isolate this population in terms of clinical and scientific efforts.

Disclosure

The authors report no conflicts of interest.