neighborhood-level stress and circadian cortisol: a systematic review and meta-analysis.

the main objective was to find association between basal cortisol and neighborhood-level stress. systematic searches, including electronic and hand searches, were conducted. the most recent date of the search was july 26, 2013. primary observational studies included if they considered stress related outcomes in the neighborhood context. using the endnote x7 advanced search option; the authors examined the abstracts and titles of the 18,092 articles to exclude obviously irrelevant studies, gray literature, discussion papers, reviews and, studies with no complete data. two authors independently extracted data from the original reports into pre-designed data extraction forms based on the data extraction template of the cochrane consumer and communication review group (cccrg). ten studies with a total of 2,134 participants were synthesized and analyzed. two studies out of ten received expanded meta-analysis. the overall effect size (95% ci) for cortisol level for residents in neighborhoods with lower stress compared to inhabitants from higher was 0.12 (0.01, 0.23). this review is demonstrating a link between psychosocial or physical stress and cortisol obtained from saliva. however, living in high disorder neighborhoods results in higher level of cortisol. this represents a biological indicator of psychosocial/physical stress exposure (i.e., neighborhood disorder) that reflects variances in stress exposure levels.