Community factors influencing child and adolescent depression: A systematic review and meta-analysis

OBJECTIVE: Depression has been identified as a priority disorder among children and adolescents. While numerous reviews have examined the individual and family factors that contribute to child and adolescent depressive symptoms, less is known about community-level risk and protective factors. The aim of this study was to complete a systematic review to identify community risk and protective factors for depression in school-aged children (4-18 years). METHOD: The review adopted the procedures recommended by the Cochrane Non-Randomised Studies Methods Working Group and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was conducted to identify both observational and intervention study designs in both peer-reviewed and non-peer reviewed publications. RESULTS: A total of 21 studies met the inclusion criteria. Seventeen of the 18 community association studies and 2 of the 3 intervention studies reported one or more significant effects. Results indicated that community safety and community minority ethnicity and discrimination act as risk factors for depressive symptoms in school-aged children. Community disadvantage failed to achieve significance in meta-analytic results but findings suggest that the role of disadvantage may be influenced by other factors. Community connectedness was also not directly associated with depressive symptoms. CONCLUSION: There is evidence that a number of potentially modifiable community-level risk and protective factors influence child and adolescent depressive symptoms suggesting the importance of continuing research and intervention efforts at the community-level.

Association of genetic vatiation within UBL5 with phenotypes of metabolic syndrome

The BEACON gene was initially identified using the differential display polymerase chain reaction on hypothalamic mRNA samples collected from lean and obese Psammomys obesus, a polygenic animal model of obesity. Hypothalamic BEACON gene expression was positively correlated with percentage of body fat, and intracerebroventricular infusion of the Beacon protein resulted in a dose-dependent increase in food intake and body weight. The human homolog of BEACON, UBL5, is located on chromosome 19p in a region previously linked to quantitative traits related to obesity. Our previous studies showed a statistically significant association between UBL5 sequence variation and several obesity- and diabetes-related quantitative physiological measures in Asian Indian and Micronesian cohorts. Here we undertake a replication study in a Mexican American cohort where the original linkage signal was first detected. We exhaustively resequenced the complete gene plus the putative promoter region for genetic variation in 55 individuals and identified five single nucleotide polymorphisms (SNPs), one of which was novel. These SNPs were genotyped in a Mexican American cohort of 900 individuals from 40 families. Using a quantitative trait linkage disequilibrium test, we found significant associations between UBL5 genetic variants and waist-to-hip ratio (p = 0.027), and the circulating concentrations of insulin (p = 0.018) and total cholesterol (p = 0.023) in fasted individuals. These data are consistent with our earlier published studies and further support a functional role for the UBL5 gene in influencing physiological traits that underpin the development of metabolic syndrome.