CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 4, July/August 2022 AFRICA 175 found that conscientiousness may protect against prospective cardiac ischaemia and hypertension risk by contributing to healthier DefS and avoidance coping responses in Africans and Caucasians respectively. Decreases in cTnT levels over a period of three years were observed in both races. Even though cTnT levels decreased over time in Africans, their mean cTnT levels after three years were still similar to 4.2 pg/ml (4.15 pg/ml), the cut-off point that has previously been related to hypertension risk in this cohort.4,13 It was proposed that these low cTnT levels may be reflective of silent cardiac ischaemic events in Africans, as positive associations were observed among these variables in a previous study.13 In the current investigation, the African group showed no frequency changes for incidence or recovery from this cut-off point, therefore showing ongoing silent cardiac ischaemia and hypertension risk at low levels of cTnT. Furthermore, a previous study indicated that this risk appears to be stress related as DefS was associated with cTnT levels above this cut-off point in the African cohort.4 Indeed, the manner of coping with mental stress has been shown to differ in the cardiovascular changes it brings about.5,6,52 Normally, a β-adrenergic vasodilation of the coronary arteries accompanies an in-control stress response, to meet the increased oxygen demand.52 A β-adrenergic profile upon stress exposure is usually associated with DefS and accompanying social support, and was also previously reported in Caucasians from the SABPA study.52 This is indicative of successful coping, as the coping resulted in stress reduction by preventing an exaggerated stress response, with subsequent negative mental and physical health outcomes.19,23 Avoidance coping, on the other hand, rather evokes an α-adrenergic vascular responsiveness, therefore adding to the oxygen demand of the heart.52 However, an α-adrenergic vascular hyper-responsivity and β-hypo-responsivity were also associated with DefS in Africans, and it was proposed that this coping strategy appears to be a stressor per se to them.6,52 In the current study, results were significant in only Africans with high DefS scores and also in Caucasians who reported high avoidance coping scores, therefore strengthening the statement that coping strategies form an integral part of the stress response. Coping strategy selection and the ultimate efficacy of the stress coping process is further partly dependent on personality traits, as these traits greatly determine the cognitive appraisals forming part of the transactional stress theory.19-23 Furthermore, while personality traits are more stable, flexibility in coping behaviour is possible.19 Investigating relationships between personality traits and coping strategy scores provided us with a better view of why the two races engaged in different coping behaviours, with different cardiac health outcomes. Although high scores within each coping strategy sub-scale indicated preferred use of that specific strategy, scoring high on multiple sub-scales is permitted by the CSI.16 High scores on multiple sub-scales are an indication of flexibility in coping strategies rather than the fixed use of one strategy for all stressors.16 The amount of Africans scoring high in DefS and seeking social support coping were similar, although fewer individuals scored high in avoidance coping, indicating that Africans rely on the former two strategies for stressor encounters. This is in agreement with other findings that social support networks can increase the efficacy of DefS.4,53 As a collectivistic culture, Africans tend to depend more on each other, explaining their tendency to make use of social support systems.3,6,53,54 The Caucasians by contrast showed flexibility with regard to DefS and avoidance coping, rather than utilising social support seeking coping. In the Caucasians’ individualistic culture, independency is regarded as important and may therefore explain why these individuals do not rely on social support coping.3,6,53,54 For Africans, the decrease in social support systems and individualism that accompanies an urbanised Western culture may leave them more emotionally distressed, which may explain their higher neuroticism score, compared to Caucasians.3,6,53 Despite a higher neuroticism score, Africans also scored lower in conscientiousness compared to Caucasians. In both races, neuroticism was associated inversely and conscientiousness positively with DefS. High conscientiousness in particular has been related to increased problem-solving coping, also known as DefS abilities, likely because these individuals experience higher levels of control over life stressors by finding taxing situations less demanding and viewing them as challenges rather than threats.33 Neuroticism rather refers to the overall tendency to view stressors as threats with inadequate coping resources to overcome it, and includes facets of anxiety, self-consciousness, depression and affective instability.29 Therefore it is clear that higher neuroticism may prevent effective DefS as coping efforts are focused at regulating emotions.55 It is therefore not surprising that neuroticism also related positively with passive emotional or avoidance coping in Africans. Zwir et al.56 proposed that organised interactions among 700 genes influence self-regulatory personality traits despite different cultures and environments. Unfortunately, the gene for the serotonin transporter polymorphism (5-HTTLPR),29,57 which is known to make a person more emotional,58 was not determined in the SABPA cohort. However, the genetic data available in the SABPA study did not suggest any relationship between BTI personality traits and mitochondrial DNA,48 tyrosine hydroxylase C-824T SNP,49 or telomere length.50 In the Caucasians, neuroticism was inversely associated with avoidance coping, but positively with social support coping. Furthermore, in the Caucasian group, conscientiousness also correlated inversely with social support coping. The discrepancy observed in the Caucasians may be explained by their individualistic culture, as theyappear toonly turn to social support systems in the event of intense negative feelings (neuroticism) and low problem-solving abilities (conscientiousness).54 Despite conscientiousness and neuroticism being among the personality traits that were mostly related to the utilisation of coping strategies in our investigation, these traits have also been shown to be mostly associated with different cardiac health outcomes in other studies.27,28,30,31,33 Our results also showed that conscientiousness was inversely related to three-year cTnT level changes in Africans with high DefS. Furthermore, both conscientiousness and neuroticism decreased the likelihood of meeting the ethnic-specific cTnT cut-off point (OR < 1.00) in the Caucasians with high avoidance coping. Personality traits such as conscientiousness and neuroticism may facilitate certain lifestyle choices, such as engaging in physical activity.59-61 Interestingly, Caucasians from the current
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