Background Dissociation between behavioural defensive active coping (AC) control albeit physiological “loss of control” responses have been associated with silent ischemia and structural wall abnormalities in African males. Whether it applies to structural endothelial dysfunction, is uncertain. We therefore aimed to determine AC ethnic-gender specific receiver operating characteristic (ROC) carotid intimae media far wall cut offs best associated with BP, silent ischemia and glycated haemoglobin (HbA1c).
Methods Participants included African and Caucasians (N = 317) without pre-existing stroke or atrial fibrillation, aged 45 ± 9 years. The Coping Strategy Indicator was used to measure AC. Ultrasound CIMTf, ambulatory BP, -silent ischemia and fasting blood samples were obtained.
Results Between 69-77% of AC African men showed above normal diastolic BP and HbA1c levels compared to 44–48% of AC Caucasian men. In AC African women, 41-60% showed above normal BP, silent ischemia and HbA1c levels compared to 17-44% of their Caucasian counterparts. From ROC curve analyses the optimal cut points detecting structural endothelial changes, yielding maximum sum of sensitivity and specificity, ranged between 0.57-0.65 mm (BP) and 0.71-0.74 mm (silent ischemia) in AC ethnic-gender groups. Only HbA1C (>5.7%) with a sensitivity/specificity 47%/74%, after controlling for confounders, predicted structural endothelial dysfunction at an optimal cut point of 0.69 mm in AC African men (OR 4.5; 95% CI 2.93 - 18.73).
Conclusion Novel findings of behavioral resilience were apparent in the AC African female despite a high prevalence of risk markers. AC facilitated chronic hyperglycemia and structural endothelial dysfunction, i.e. a physiological “loss of control” and susceptibility to stroke risk in African men.