Combined pattern of childhood psycho-behavioral characteristics in patients with schizophrenia: a retrospective study in Japan

Hair zinc levels and psychosis risk among adolescents

Recent meta-analyses have shown lower zinc and higher copper levels in the serum of people with schizophrenia than in healthy controls. However, the relationship between trace elements (TEs) and the pathophysiology of psychosis, including schizophrenia, remains unclear due to the antipsychotic effects on mineral levels. In this study, we aimed to determine the relationship between zinc and copper levels in hair and psychosis risk among drug-naïve adolescents. This study was conducted as a part of a population-based biomarker subsample study of the Tokyo Teen Cohort Study, including 252 community-dwelling 14-year-old drug-naïve adolescents. Zinc and copper levels in hair were measured using inductively coupled plasma mass spectrometry. The thought problems (TP) scale from the Child Behavior Checklist was used to evaluate psychosis risk. Regression analysis showed that hair zinc levels were negatively correlated with the TP scale (T-score) (β = -0.176, P = 0.005). This result remained significant after adjusting for age and sex (β = -0.175, P = 0.005). In contrast, hair copper levels were not associated with the TP scale (T-score) (β = 0.026, P = 0.687). These findings suggest that lower zinc levels could be involved in the pathophysiology of psychosis, independent of antipsychotics. Further longitudinal studies are required to investigate whether hair zinc level is a useful new biomarker for assessing psychosis risk.

Preliminary study of the social withdrawal (hikikomori) spectrum in French adolescents: focusing on the differences in pathology and related factors compared with Japanese adolescents

BACKGROUND

Social withdrawal (hikikomori) has become an internationally recognized phenomenon, but its pathology and related factors are not yet fully known. We previously conducted a statistical case-control study on adolescent patients with hikikomori in Japan, which revealed the non-specificity of pathology in patients with hikikomori. Further, environmental factors, such as the lack of communication between parents and Internet overuse, were found to be significant predictors of hikikomori severity. Here, we aimed to conduct a similar preliminary case-control study in France and to compare the results with those from the study conducted in Japan.

METHODS

Parents of middle school students who underwent psychiatric outpatient treatment for hikikomori (n = 10) and control group parents (n = 115) completed the Child Behavior Checklist to evaluate their child's psychopathological characteristics and the Parental Assessment of Environment and Hikikomori Severity Scales, as in our previous study in Japan. We compared the descriptive statistics and intergroup differences in France with those from the previous study conducted in Japan. In the multiple regression analysis to find predictors of hikikomori severity in French and also Japanese subjects, the same dependent and independent variables were chosen for the present study (both differed from the previous study). These were used in order to make accurate intercountry comparisons.

RESULTS

The comparisons revealed no differences in the pathology of hikikomori between Japan and France. Specifically, both studies found similarly increased scores for all symptom scales, with no specific bias. However, the statistical predictors of hikikomori severity in France (lack of communication between parents and child and lack of communication with the community) differed from those in Japan (lack of communication between parents).

CONCLUSION

Hikikomori in Japan and France could be considered essentially the same phenomenon; moreover, our findings demonstrated the universal non-specificity and unbiasedness of the hikikomori pathology. This suggests that hikikomori is not a single clinical category with a specific psychopathology; instead, it is a common phenotype with various underlying pathologies. However, different strategies may be required in each country to prevent the onset and progression of hikikomori.

Cognitive deficits in familial schizophrenia

BACKGROUND

Cognitive impairment is a core feature of schizophrenia and has been observed in subjects with and without a family history of schizophrenia. Nonetheless, there is a paucity of research directly contrasting cognitive profiles in schizophrenia patients and normal people where family history is present and those where the family history is absent.

AIM

This stydy aimed to compare cognitive functions in patients with schizophrenia who had a family history with those that did not and healthy controls.

MATERIALS AND METHODS

Fifty consecutive schizophrenia patients were assessed on admission and follow-up after 6 months of treatment using a specially prepared pro forma, the Positive and Negative Syndrome Scale, and the PGI Battery of brain dysfunction is the name give to the test. An equal number of age- and sex-matched normal control subjects were also assessed.

RESULTS

Visual memory scores in this study show improvement between baseline and follow-up in schizophrenia patients with/without a family history. Both verbal learning and memory increase between baseline and follow-up but do not reach control levels. Reasoning and problem-solving deficits follow a similar pattern and are causative in the inability to adapt to a changing world. Speed of processing shows improvement with treatment. Working memory deficits in patients improve with treatment.

CONCLUSIONS

In this study, all six cognitive domain scores in schizophrenia improved after 6 months of treatment but did not reach the control population level. Individuals with the highest cognitive deficits in the scales were the ones who had a family history of schizophrenia.