Concise set of files for smooth return to work in employees with mental disorders.

Sick leave due to mental disorders is a societal problem. It carries a high cost in terms of loss of labor productivity and absenteeism. Partial remission increases the risk of relapse after a return to work. There is sometimes a difference between the ability to return to work as judged by a general practitioner (GP) and the needs of the workplace. GPs are the main controllers of treatment and tend to protect their patients. Communication and agreement by GPs and occupational physicians play an effective role in the return to work. However, it requires considerable effort for both of them to make time to do this. We have developed a concise set of files for a smooth return to work. The files consist of three parts: "Suggestions for corresponding with employees taking sick leave"; "Checklist for smooth return to work"; and "Pattern of living". We put them into practice among 20 companies in Japan from January 2012 to October 2013. The companies had 8244 workers in total and 116 workers were on sick-leave due to mental disorders. Our set of files contributed to sharing the written basic policy of return to work among employees on sick leave with mental disorders, GPs, occupational physicians and personnel officers. That sharing led to facilitating a smooth return to work. Although there are differences in the legal and medical systems between Japan and other countries, our concept of sharing the written basic policy may give some help to occupational physicians in other parts of the world as well.

A novel scale including strabismus and 'cuspidal ear' for distinguishing schizophrenia patients from controls using minor physical anomalies.

The present study explored minor physical anomaly items relevant to schizophrenia in order to establish a scale that can distinguish schizophrenia from controls using newly identified items along with items from the refined Waldrop scale. Seven items were significantly more frequent among schizophrenia patients (N=218) than controls (N=226). Among these seven items, two novel features, strabismus and 'cuspidal ear' showed markedly different prevalence rates between schizophrenia and control groups. A six-item scale, including the newly identified strabismus and cuspidal ear, was selected for most accurately discriminating patients with schizophrenia from controls. This scale correctly classified 59.6% of patients and 78.9% of control subjects. This new scale is procedurally more exacting and quantitative, and more relevant to schizophrenia than the original Waldrop scale. The validity of this scale should be sound since it was tested on a larger number of cohorts than used in previous research. Our scale can be used as a biomarker for predicting risk for future development of schizophrenia. The scale may also facilitate the identification of schizophrenia susceptibility genetic/environmental factors by stratifying etiologically heterogeneous patients according to physical abnormalities.

Association of an orexin 1 receptor 408Val variant with polydipsia-hyponatremia in schizophrenic subjects.

BACKGROUND: Primary polydipsia is a common complication in patients with chronic psychoses, particularly schizophrenia. Disease pathogenesis is poorly understood, but one contributory factor is thought to be dopamine dysregulation caused by prolonged treatment with neuroleptics. Both angiotensin-converting enzyme (ACE) and orexin (hypocretin) signaling can modulate drinking behavior through interactions with the dopaminergic system. METHODS: We performed association studies on the insertion/deletion (I/D) sequence polymorphism of ACE and single nucleotide polymorphisms within the prepro-orexin (HCRT), orexin receptor 1 (HCRTR1), and orexin receptor 2 (HCRTR2) genes. Genotypes were determined by polymerase chain reaction amplification, followed by either electrophoretic separation or direct sequencing. RESULTS: The ACE I/D polymorphism showed no association with polydipsic schizophrenia. Screening of the orexin signaling system detected a 408 isoleucine to valine mutation in HCRTR1 that showed significant genotypic association with polydipsic-hyponatremic schizophrenia (p = .012). The accumulation of this mutation was most pronounced in polydipsic versus nonpolydipsic schizophrenia (p = .0002 and p = .008, for the respective genotypic and allelic associations). The calcium mobilization properties and the protein localization of mutant HCRTR1 seem to be unaltered. CONCLUSION: Our preliminary data suggest that mutation carriers might have an increased susceptibility to polydipsia through an undetermined mechanism.

Association between schizophrenia with ocular misalignment and polyalanine length variation in PMX2B.

The increased incidence of minor physical anomalies (MPAs) in schizophrenia is the fundamental basis for the neurodevelopmental hypothesis of schizophrenia etiology. Ocular misalignment, or strabismus, falls into the category of MPAs, but this phenotype has not been assessed in schizophrenia. This study reveals that a subtype of strabismus, constant exotropia, displays marked association with schizophrenia (P=0.00000000906). To assess the genetic mechanisms, we examined the transcription factor genes ARIX (recently identified as a causative gene for syndromic strabismus) and its paralogue, PMX2B. We identified frequent deletion/insertion polymorphisms in the 20-alanine homopolymer stretch of PMX2B, with a modest association between these functional polymorphisms and constant exotropia in schizophrenia (P=0.029). The polymorphisms were also associated with overall schizophrenia (P=0.012) and more specifically with schizophrenia manifesting strabismus (P=0.004). These results suggest a possible interaction between PMX2B and other schizophrenia-precipitating factors, increasing the risk of the combined phenotypes. This study also highlights the unique nature of the polyalanine length variations found in PMX2B. In contrast with other transcription factor genes, the variations in PMX2B show a high prevalence, with deletions being more common than insertions. Additionally, the polymorphisms are of ancient origin and stably transmitted, with mild phenotypic effects. In summary, our study lends further support to the disruption of neurodevelopment in the etiology of schizophrenia, by demonstrating the association of a specific MPA, in this case, constant exotropia with schizophrenia, along with molecular variations in a possible causative gene.

A microsatellite repeat in the promoter of the N-methyl-D-aspartate receptor 2A subunit (GRIN2A) gene suppresses transcriptional activity and correlates with chronic outcome in schizophrenia.

Hypofunction of the N-methyl-D-aspartate (NMDA) receptor has been hypothesized to underlie the pathophysiology of schizophrenia, based on the observation that non-competitive antagonists of the NMDA receptor, such as phencyclidine, induce schizophrenia-like symptoms. Mice lacking the NR2A subunit of the NMDA receptor complex are known to display abnormal behaviour, similar to schizophrenic symptoms. The expression of NR2A starts at puberty, a period corresponding to the clinical onset of schizophrenia. This evidence suggests that the NR2A (GRIN2A) gene may play a role in the development of schizophrenia and disease phenotypes. In this study, we performed a genetic analysis of this gene in schizophrenia. Analysis of the GRIN2A gene detected four single nucleotide polymorphisms, and a variable (GT)(n) repeat in the promoter region of the gene. A case-control study (375 schizophrenics and 378 controls) demonstrated evidence of an association between the repeat polymorphism and the disease (P = 0.05, Mann-Whitney test), with longer alleles overly represented in patients. An in-vitro promoter assay revealed a length dependent inhibition of transcriptional activity by the (GT)(n) repeat, which was consistent with a receptor binding assay in postmortem brains. Significantly, the score of symptom severity in chronic patients correlated with repeat size (P = 0.01, Spearman's Rank test). These results illustrate a genotype-phenotype correlation in schizophrenia and suggest that the longer (GT)(n) stretch may act as a risk-conferring factor that worsens chronic outcome by reducing GRIN2A levels in the brain.

Distribution of haplotypes derived from three common variants of the NR4A2 gene in Japanese patients with schizophrenia.

Dysregulation in dopaminergic neurotransmission might play a role in the pathogenesis of schizophrenia, and therefore genetic components of the dopamine (DA) pathway may confer risk. The NR4A2 (Nurr1) gene is essential for the development and maintenance of mesencephalic DA-synthesizing neurons. Moreover, Nurr1 forms a heterodimer with the retinoid X receptor and disturbances in the retinoid-signaling cascade may be involved in susceptibility to schizophrenia. To investigate the potential genetic contribution of NR4A2, we performed a case-control association study using three common variants in the gene [-2922(C)2-3, IVS6 + 17 approximately +18insG, EX8 + 657(CA)9-10] that were in strong linkage disequilibrium with each other. We did not detect a significant allelic or genotypic association. Haplotypes derived from all three polymorphisms generated similar results. These data do not support the notion that the NR4A2 gene plays a major role in risk for schizophrenia among Japanese individuals.

Fine mapping of an isodicentric Y chromosomal breakpoint from a schizophrenic patient.

We report on a male schizophrenic patient who carried an isodicentric Y chromosome [idic(Y)] with a mosaic karyotype [mos 45,X/46,X,idic(Y)(q11)]. Although a potential association between sex chromosome abnormalities and a susceptibility to psychoses has been documented, there has only been one previous report of idic(Y) coincident with schizophrenia. The [45,X] karyotype is known to be associated with Turner syndrome (TS), but our patient lacked most of the phenotypic features of TS, except for short stature. To define the precise position of the breakpoint on the patient's abnormal Y chromosome, we carried out polymerase chain reaction (PCR) analysis, using primers for 15 marker loci along the chromosome. The breakpoint was localized to between the marker loci sY118 and sY119 on Yq in the 5M interval of the deletion map. This position represents the most centromeric breakpoint recorded for idic(Y). We cannot exclude the possibility that the development of schizophrenia is unrelated to the Y chromosome abnormality in this patient but we hope that this study will stimulate further cytogenetic and molecular genetic analyses of Y chromosome regions that may influence psychiatric traits.