Possible Modulatory Role of ARC Gene Variants in Mood Disorders

Objective@#The genetic background of mood disorders is gradually emerging through the use of large multicenter samples but a detailed phenotyping is complementary in elucidating the role of modulating variants. @*Methods@#In the present paper we focused on the possible modulatory effects of ARC gene variants on two independent mood disorder samples of European (n = 246 bipolar disorder) and Korean (n = 132 bipolar disorder; n = 242 major depressive disorder [MDD]) ancestry. @*Results@#No result survived Bonferroni correction, however we evidenced promising trend toward possible association between ARC gene variants and mood disorder phenotypes. In particular, we evidenced weak correlations of ARC single nucleotide polymorphisms with depressive symptoms severity (evaluated through Hamilton depression rating scale scores) in the MDD Korean (rs7465272) and European (rs11167152) samples. Additionally rs10110456 was found to be related to Family History, while rs7465272 was related to suicide risk in the Korean sample. Finally, rs7465272 was associated with body mass index in the European sample. @*Conclusion@#Overall, ARC gene variants may have a partial role in modulatory effect on treatment efficacy or phenotypes of mood disorders. Further studies, on larger samples may provide a better understanding on the role of ARC gene variants in the symptom severity and treatment outcomes in patients with mood disorders.

Dimensions of Delusions in Major Depression: Socio-demographic and Clinical Correlates in an Unipolar-Bipolar Sample

OBJECTIVE: The present study aims at exploring associations between a continuous measure of distorted thought contents and a set of demographic and clinical features in a sample of unipolar/bipolar depressed patients. METHODS: Our sample included 1,833 depressed subjects. Severity of mood symptoms was assessed by the 21 items Hamilton Depression Rating Scale (HAM-D). The continuous outcome measure was represented by a delusion (DEL) factor, extracted from HAM-D items and including items: 2 ("Feelings of guilt"), 15 ("Hypochondriasis"), and 20 ("Paranoid symptoms"). Each socio-demographic and clinical variable was tested by a generalized linear model test, having depressive severity (HAM-D score-DEL score) as the covariate. RESULTS: A family history of major depressive disorder (MDD; p=0.0006), a diagnosis of bipolar disorder, type I ( p=0.0003), a comorbid general anxiety disorder (p<0.0001), and a higher number of manic episodes during lifetime (p<0.0001), were all associated to higher DEL scores. Conversely, an older age at onset (p<0.0001) and a longer duration of hospitalization for depression over lifetime (p=0.0003) had a negative impact over DEL scores. On secondary analyses, only the presence of psychotic features (p<0.0001) and depressive severity (p<0.0001) were found to be independently associated to higher DEL scores. CONCLUSION: The retrospective design and a non validated continuous measure for distorted thought contents were the main limitations of our study. Excluding the presence of psychotic features and depressive severity, no socio-demographic or clinical variable was found to be associated to our continuous measure of distorted thinking in depression.