title: Defensive active coping facilitates chronic hyperglycaemia and endothelial dysfunction in African men: the SABPA study.
abstract: BACKGROUND
  Dissociation between behavioural defensive active coping (AC) control albeit physiological "loss of control" responses was associated with silent ischaemia and structural wall abnormalities in African men. Whether it applies to structural alterations and endothelial dysfunction is uncertain. We therefore aimed to determine AC ethnic-gender specific receiver operating characteristic (ROC) carotid intima media far wall (CIMTf) cut points best associated with 24-h BP, -silent ischaemia 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 ischaemia and fasting blood samples were obtained.
  
  
  RESULTS
  Between 69 and 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 ischaemia and HbA1c levels compared to 17-44% of their Caucasian counterparts. ROC curve analyses, detecting optimal CIMTf cut points, ranged between 0.57 and 0.65 mm (BP) and 0.71 and 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 structural alterations at an optimal cut point of 0.69 mm in AC African men (OR 4.5; 95% CI 2.93-18.73).
  
  
  CONCLUSIONS
  Novel findings of behavioural resilience were apparent in the AC African female despite a high prevalence of risk markers. In AC males, chronic hyperglycaemia facilitated endothelial dysfunction, i.e. a physiological "loss of control" and susceptibility to stroke risk.
authors.affiliation: Hypertension in Africa Research Team (HART), School for Physiology, Nutrition and Consumer Sciences, North-West University, Potchefstroom Campus, South Africa. Electronic address: leone.malan@nwu.ac.za.
authors.forename: L
authors.initials: L
authors.lastname: Malan
authors.forename: M
authors.initials: M
authors.lastname: Hamer
authors.forename: M P
authors.initials: MP
authors.lastname: Schlaich
authors.forename: G W
authors.initials: GW
authors.lastname: Lambert
authors.forename: T
authors.initials: T
authors.lastname: Ziemssen
authors.forename: M
authors.initials: M
authors.lastname: Reimann
authors.forename: H S
authors.initials: HS
authors.lastname: Steyn
authors.forename: R
authors.initials: R
authors.lastname: Schutte
authors.forename: W
authors.initials: W
authors.lastname: Smith
authors.forename: J M
authors.initials: JM
authors.lastname: van Rooyen
authors.forename: C M T
authors.initials: CM
authors.lastname: Fourie
authors.forename: N T
authors.initials: NT
authors.lastname: Malan
mesh_terms: D000223:Adaptation, Psychological / Q000502:physiology; D000328:Adult; D044383:Black People / Q000208:ethnology* / Q000523:psychology; D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods* / Q000523:psychology; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D003674:Defense Mechanisms; D004562:Electrocardiography / Q000379:methods / Q000523:psychology; D006801:Humans; D006943:Hyperglycemia / Q000208:ethnology* / Q000503:physiopathology / Q000523:psychology; D008297:Male; D008875:Middle Aged; D013019:South Africa / Q000208:ethnology; D014652:Vascular Diseases / Q000208:ethnology* / Q000503:physiopathology / Q000523:psychology; D044465:White People / Q000208:ethnology / Q000523:psychology