Silent ischemia is associated with subclinical atherosclerosis in African males: the sympathetic activity and ambulatory blood pressure in Africans study.
Silent myocardial ischemia is a predictor of subclinical atherosclerosis driven by increased cardiovascular risk markers, although still unknown in Africans. The aim of this study was to assess if cardiovascular risk markers will be associated with subclinical atherosclerosis. African men were stratified into (i) 24-hour silent ischemia (SI, n = 38) and (ii) without (nSI, n = 40) groups. Ambulatory blood pressure (BP), SI, 12-lead resting electrocardiogram, ultrasound carotid intima-media thickness (CIMT) measurements, and fasting blood samples were obtained. Above-normal cardiovascular risk markers, that is, glucose level, heart rate, BP, and CIMT, were evident in men with SI. Hypertension prevalence was 89% in the African SI men as opposed to 64% in the nSI men. Regression analyses revealed that only SI events in SI men explained 35% (95% confidence interval [CI]: 0.22;0.52) of the variance in CIMT, while in all African men it explained 29% (95% CI: 0.19;0.39). In conclusion, SI was associated with structural vascular disease in African men. This could imply that SI is not necessarily driven by hypertension in African men but through other possible mechanisms such as increased sympathetic nervous system activity.
Hypertension in Africa Research Team, School for Physiology, Nutrition and Consumer Sciences, North-West University, Potchefstroom, South Africa.
Madelein E
ME
Griffiths
Leoné
L
Malan
Johannes M
JM
van Rooyen
Gerhard
G
Koekemoer
Chris B
CB
Vorster
D000328:Adult; D000349:Africa / Q000453:epidemiology; D050197:Atherosclerosis / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000209:etiology*; D012307:Risk Factors; D012737:Sex Factors