The Association of Neighborhood Gene-Environment Susceptibility with Cortisol and Blood Pressure in African-American Adults

• Published in: Annals of behavioral medicine 2016-02, Vol.50 (1), p.98-107
• Main Authors: Coulon, Sandra M., Wilson, Dawn K., Van Horn, M. L., Hand, Gregory A., Kresovich, Stephen
• Format: Article
• Language: English
• Subjects: African Americans; African Americans - genetics; Blood pressure; Blood Pressure - physiology; Cross-Sectional Studies; Cyclin D1 - genetics; Family Medicine; Female; Gene-Environment Interaction; General Practice; Genetic Predisposition to Disease - genetics; Genotype; Health Psychology; Hormones; Humans; Hydrocortisone - metabolism; Male; Medicine; Medicine & Public Health; Middle Aged; Neighborhoods; Original Article; Polymorphism, Single Nucleotide - genetics; Receptors, Glucocorticoid - genetics; Residence Characteristics; Saliva - metabolism; Social Class; Socioeconomic factors; Status; Tacrolimus Binding Proteins - genetics
• ISSN: 0883-6612; 1532-4796
• DOI: 10.1007/s12160-015-9737-9

Background African-American adults are disproportionately affected by stress-related chronic conditions like high blood pressure (BP), and both environmental stress and genetic risk may play a role in its development. Purpose This study tested whether the dual risk of low neighborhood socioeconomic status (SES) and glucocorticoid genetic sensitivity interacted to predict waking cortisol and BP. Methods Cross-sectional waking cortisol and BP were collected from 208 African-American adults who were participating in a follow-up visit as part of the Positive Action for Today’s Health trial. Three single-nucleotide polymorphisms were genotyped, salivary cortisol samples were collected, and neighborhood SES was calculated using 2010 Census data. Results The sample was mostly female (65 %), with weight classified as overweight or obese ( M BMI  = 32.74, SD  =  8.88) and a mean age of 55.64 (SD = 15.21). The gene-by-neighborhood SES interaction predicted cortisol ( B  = 0.235, p  = .001, r 2  = .036), but not BP. For adults with high genetic sensitivity, waking cortisol was lower with lower SES but higher with higher SES ( B  = 0.87). Lower neighborhood SES was also related to higher systolic BP ( B  = −0.794, p  = .028). Conclusions Findings demonstrated an interaction whereby African-American adults with high genetic sensitivity had high levels of waking cortisol with higher neighborhood SES, and low levels with lower neighborhood SES. This moderation effect is consistent with a differential susceptibility gene-environment pattern, rather than a dual-risk pattern. These findings contribute to a growing body of evidence that demonstrates the importance of investigating complex gene-environment relations in order to better understand stress-related health disparities.