Size at birth and autonomic function during psychological stress.

Small size at birth is associated with exaggerated blood pressure responses to psychological stressors, which increase the risk of developing sustained hypertension in adult life. Explanatory mechanisms for this association are not well characterized. We investigated the hypothesis that an adverse fetal environment, reflected by small size at birth, persistently alters autonomic nervous system and baroreflex control of cardiovascular function, resulting in exaggerated blood pressure and heart rate responses to stressors.

Size at birth and cardiovascular responses to psychological stressors: evidence for prenatal programming in women.

Background: Epidemiological studies have repeatedly shown inverse associations between size at birth and blood pressure in later life. There is some evidence to suggest that exaggerated blood pressure responses to psychological stressors are a forerunner of sustained hypertension.

Objective: To determine whether individuals who were smaller at birth have greater blood pressure and heart rate responses to psychological stressors.

Central hypothalamic-pituitary-adrenal activity and the metabolic syndrome: Studies using the corticotrophin-releasing hormone test.

A number of studies have suggested that the metabolic syndrome (principally, the combination of hypertension, glucose intolerance, and dyslipidemia) is associated with subtle dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis leading to raised circulating cortisol concentrations. The mechanisms underlying these observations are not known. We assessed the salivary cortisol response to awakening and pituitary-adrenal responses during a 100-microg human corticotrophin-releasing hormone (CRH) test and a dexamethasone-suppressed CRH test in a well-characterized group of 65-year-old men (n = 122).

Fetal programming of the hypothalamic-pituitary-adrenal (HPA) axis: low birth weight and central HPA regulation.

Fetal programming of the hypothalamic-pituitary-adrenal (HPA) axis has been proposed as an intermediary in the association between reduced fetal growth and adult cardiovascular and metabolic diseases. Previous studies have shown that small size at birth is associated with increased fasting plasma cortisol and adrenal responsiveness to ACTH stimulation. We have extended these studies by evaluating the salivary cortisol response to awakening and plasma ACTH and cortisol responses to CRH stimulation and a dexamethasone-suppressed CRH (DEX/CRH) test in a group of low birth weight [LBW; <3.

Cortisol and the metabolic syndrome in South Asians.

Objective: The cardiovascular risk factors which comprise the metabolic syndrome are associated with increased hypothalamic-pituitary-adrenal axis (HPAA) activity in some Caucasian populations. South Asians have high rates of cardiovascular disease and its risk factors. We have investigated the relationships between HPAA activity, adiposity and the metabolic syndrome in a South Asian population.