Background and Objectives:
Defensive active coping (AC) responses have been associated with disturbed vascular function but whether it applies to early structural vascular changes, is uncertain. We therefore aimed to determine receiver operating characteristic (ROC) carotid intima media far wall (CIMTf) cut offs best associated with risk markers namely 24 h BP, -silent ischaemia and glycated hemoglobin (HbA1c).
Design and Methods:
Our sub study included 317 Africans and Caucasians from the original SABPA prospective cohort study without pre-existing stroke or atrial fibrillation, aged 45 ± 9 years. Significant interaction on main effects necessitated selection of AC above mean. We collected ultrasound CIMTf, 24 h BP, -silent ischaemia data and overnight fasting blood samples.
Between 69-77% of AC African men showed above normal diastolic BP and HbA1c levels compared to 44–48% of AC Caucasian men. In the AC African women, 41-60% showed above normal BP, silent ischaemia and HbA1c levels compared to 17-44% of their Caucasian counterparts. ROC cut points detecting early structural changes ranged between 0.57-0.65 mm (BP) and 0.71-0.74 mm (silent ischaemia) in AC ethnic-gender groups. Only HbA1C (>5.7%) with a sensitivity/specificity 47%/74%, after controlling for confounders, predicted early structural vascular changes at an optimal cut point of 0.69 mm in AC African men (OR 4.5; 95% CI 2.93 - 18.73).
Behavioral resilience was apparent in the African female despite a high prevalence of risk markers. A defensive coping strategy facilitated chronic hyperglycemia and early structural vascular changes in the African male, possibly increasing stroke risk.
© 2012 Lippincott Williams & Wilkins, Inc.