Childhood socioeconomic status and serotonin transporter gene polymorphism enhance cardiovascular reactivity to mental stress.

OBJECTIVE: To test the hypothesis that low socioeconomic status (SES) and the 5HTTLPR L allele are associated with increased cardiovascular reactivity (CVR) to stress in a larger sample and that SES and 5HTTLPR genotypes interact to enhance CVR to stress. CVR to mental stress has been proposed as one mechanism linking stress to the pathogenesis of cardiovascular disease. The more transcriptionally efficient long (L) allele of a polymorphism of the serotonin transporter gene promoter (5HTTLPR) has been found associated with increased risk of myocardial infarction. We found the long allele associated with larger CVR to mental stress in a preliminary study of 54 normal volunteers. METHODS: Subjects included 165 normal community volunteers stratified for race, gender, and SES, who underwent mental stress testing. RESULTS: Childhood SES as indexed by Father's Education Level was associated with larger systolic blood pressure (SBP) (p < .05) and diastolic blood pressure (DBP) (p = .01) responses to mental stress. The L allele was associated with larger SBP (p = .04), DBP (p < .0001), and heart rate (p = .04) responses to mental stress compared with the short (S) allele. Subjects with the SS genotype and high Father's Education exhibited smaller SBP (5.2 mm Hg) and DBP (2.9 mm Hg) responses than subjects with LL genotype and low Father's Education (SBP = 13.3 mm Hg, p = .002; DBP = 9.7 mm Hg, p < .0001). CONCLUSIONS: Both the 5HTTLPR long allele and low SES, particularly during childhood, are associated with increased CVR to mental stress, which could account, at least in part, for the increased cardiovascular disease risk associated with these characteristics. If confirmed in further research, these characteristics could be used to identify persons who might benefit from preventive interventions.

Depressive symptoms, race, and glucose concentrations: the role of cortisol as mediator.

OBJECTIVE: This study examined the associations of depressive symptoms with glucose concentrations and morning cortisol levels in 665 African-American and 4,216 Caucasian Vietnam-era veterans. RESEARCH DESIGN AND METHODS: Glucose level was measured as a three-level variable (diabetes, impaired glucose, and normal). Depressive symptoms were measured by the Obvious Depression Scale (OBD) from the Minnesota Multiphasic Personality Inventory. RESULTS: Regression models showed significant race x OBD interactions in relation to glucose concentration (P < 0.0001) and cortisol (P < 0.0001). The OBD was positively associated with glucose concentration and cortisol in both racial groups. However, the magnitude of those associations was larger for African Americans. Further analyses suggested that cortisol partially mediated the race difference in the relation of depressive symptoms to glucose concentrations. CONCLUSIONS: These results suggest that enhanced hypothalamic pituitary adrenal activity plays an important role in the relation of depressive symptoms to dysregulated glucose metabolism and may partially explain the differential effects of depressive symptoms on glucose levels in African-American and Caucasian male subjects.

Treatment regimen determines the relationship between depression and glycemic control.

UNLABELLED: Several recent studies have suggested that depression is related to poorer glycemic control in patients with type 1 diabetes, but not in type 2 diabetes. We hypothesize that complexity of self-care regimen rather than the type of diabetes, is more important in determining this relationship of depression to glycemic control. METHODS: One thousand thirty-four adults with diabetes were recruited for the study. These patients were treated with: diet and exercise, oral medications, oral medications and insulin, 1-2 daily injections of insulin, and > or =3 daily injections. All participants completed the Beck depression inventory (BDI) and had a hemoglobin A(1c) (HbA(1c)) performed as part of routine clinical care. RESULTS: Pearson correlations between BDI scores and HbA(1c) were low and insignificant in all groups (0.015< or =r< or =0.066) except for those administering three or more daily shots of insulin (r=0.284; p=0.034). DISCUSSION: The results of this study clearly show that while depressive symptoms are significantly correlated to glycemic control in patients taking three or more insulin injections per day, there is no relationship in patients who are taking fewer than three injections per day.