Even though the role of the DICS1 gene as a risk factor for schizophrenia is still unclear, there is substantial evidence from functional and cell biology studies that supports the connection of the gene with schizophrenia. The studies associating the DISC1 gene with schizophrenia in Asian populations are limited to East-Asian populations. Our study examined several DISC1 markers of schizophrenia that were identified in the Caucasian and East-Asian populations in Malaysia and assessed the role of rs2509382, which is located at 11q14.3, the mutual translocation region of the famous DISC1 translocation [t (1; 11) (p42.1; q14.3)].
INTRODUCTION: The present study investigated the relationship between psychological symptoms and psychosocial function and the role of relevant sociodemographic data and antipsychotic use in the prediction of psychosocial function among multiracial schizophrenia outpatients in Malaysia.
METHODS: A total of 223 participants were recruited in this cross-sectional study conducted from December 2010 to April 2011. Psychological symptoms were assessed using the Positive and Negative Syndrome Scale whilst the psychosocial function was assessed using the Personal and Social Performance scale. Sociodemographic and treatment variables were gathered through interview or review of the medical records.
RESULTS: All dimensions of psychosocial functions were inversely correlated with Positive and Negative Syndrome Scale sub-domains. Only the disorganization sub-domain significantly predicts all dimensions of psychosocial function. For social data, body mass index and employment status were significant predictors of all dimensions of psychosocial functions. Typical antipsychotics significantly predict social function negatively as compared to sulpiride (β = -0.152, P = 0.028).
DISCUSSION: We found that the relationship between psychological symptoms and psychosocial functions were relatively consistent with the findings from the Caucasian population. Additionally, disorganization was the only significant predictor of all dimensions of psychosocial functions. This further emphasized the importance of cognition in psychosocial function. The roles of sulpiride, body mass index and employment status as predictors of psychosocial function were also discussed.
KEYWORDS: antipsychotics; psychosocial function; schizophrenia; symptoms
Study site: Psychiatric clinic, Hospital Tengku Ampuan Afzan, Kuantan, Pahang, Malaysia
OBJECTIVES. Obesity is an issue of concern among patients with schizophrenia as it is a co-morbid condition that is closely related to metabolic syndrome. The present study assessed the correlation of body mass index with antipsychotic use among multiracial schizophrenia outpatients. The study also compared the patients' body mass index with Malaysian Adult Nutrition Survey (MANS) data.
METHODS. A total of 216 participants were recruited into a cross-sectional study conducted over 5 months, from December 2010 to April 2011. Body weight and height were measured using the standard methods. Demographic data and treatment variables were gathered through interview or review of the medical records.
RESULTS. There were differences in mean body mass index between men and women (p = 0.02) and between Malay, Chinese and Indian races (p = 0.04). Stratified by sex, age, and race, the body mass index distributions of the patients were significantly different to those of the reference MANS population. The prevalence of obesity among patients was more than 2-fold greater than among the reference population in all variables. Although body mass index distribution was related to antipsychotic drugs (χ(2) = 33.42; p = 0.04), obesity could not be attributed to any specific drug.
CONCLUSION. The prevalence of obesity among patients with schizophrenia was significantly greater than that in the healthy Malaysian population, and affects the 3 main races in Malaysia.
Study site: Psychiatry Clinic, Tengku Ampuan Afzan Hospital, Kuantan, Pahang, Malaysia.
Polymorphisms within the beta2-adrenergic receptor (ADRB2) gene have been repeatedly linked to hypertension. Among the ADRB2 polymorphisms detected, Arg16Gly and Gln27Glu codons are considered the two most important variations. The amino acid substitution at these codons may lead to abnormal regulation of ADRB2 activity. The aim of the present study was to assess the association between ADRB2 polymorphisms and hypertension. This case-control study consisted of 100 unrelated subjects (50 hypertensive and 50 matched normal controls). Arg16Gly and the Gln27Glu polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay. There were no significant evidence of association in allelic and genotypes distribution of Arg16Gly and Glu27Gln with blood pressure and hypertension. These findings suggest that the variation within codon 16 and 27 of ADRB2 gene were unlikely to confer genetic susceptibility for hypertension in our population samples.
The epigenetic changes of RELN that are involved in the development of dopaminergic neurons may fit the developmental theory of schizophrenia. However, evidence regarding the association of RELN DNA methylation with schizophrenia is far from sufficient, as studies have only been conducted on a few limited brain samples. As DNA methylation in the peripheral blood may mirror the changes taking place in the brain, the use of peripheral blood for a DNA methylation study in schizophrenia is feasible due to the scarcity of brain samples. Therefore, the aim of our study was to examine the relationship of DNA methylation levels of RELN promoters with schizophrenia using genomic DNA derived from the peripheral blood of patients with the disorder. The case control studies consisted of 110 schizophrenia participants and 122 healthy controls who had been recruited from the same district. After bisufhite conversion, the methylation levels of the DNA samples were calculated based on their differences of the Cq values assayed using the highly sensitive real-time MethyLight TaqMan® procedure. A significantly higher level of methylation of the RELN promoter was found in patients with schizophrenia compared to controls (p = 0.005) and also in males compared with females (p = 0.004). Subsequently, the RELN expression of the methylated group was 25 fold less than that of the non-methylated group. Based upon the assumption of parallel methylation changes in the brain and peripheral blood, we concluded that RELN DNA methylation might contribute to the pathogenesis of schizophrenia. However, the definite effects of methylation on RELN function during development and also in adult life still require further elaboration.