Soluble urokinase plasminogen activator receptor and hypertension among black South Africans after 5 years

Soluble urokinase plasminogen activator receptor (suPAR) is a biomarker that links inflammation with cardiovascular risk. "However, studies linking suPAR and hypertension are scant. First, we determined whether baseline suPAR is elevated in" "normotensive black South Africans who developed hypertension over 5 years, compared with those who remained normotensive; and second, whether hypertension is associated with suPAR. This substudy is embedded in the South African leg of the Prospective Urban and Rural Epidemiology study, performed in the North West Province. We investigated 429 normotensive individuals, of which 191 developed hypertension and 238 remained normotensive over 5 years. We determined suPAR from plasma (ethylenediaminetetraacetic acid) samples with the suPARnostic ELISA Kit and blood pressure with an OMRON HEM–757 device. Despite similar mean baseline suPAR levels (P=0.43), suPAR increased more in the group that developed hypertension compared with those who remained normotensive (14.2% vs. 6.94%; P=0.007). Five–year percentage change in systolic blood pressure correlated positively (r=0.23; P=0.002) and associated independently with baseline suPAR (?=0.14; P=0.043), only in participants who developed hypertension. Participants were 1.41 times more likely (P=0.015) to develop hypertension with 1 s.d. increase in percentage change in suPAR levels over 5 years. Change in systolic blood pressure was associated with baseline suPAR in hypertensive participants and change in suPAR with hypertensive status. This study highlights the need for more research on the role of suPAR in hypertension and cardiovascular disease development in black South" Africans

Serum calcium revisited: associations with 24-h ambulatory blood pressure and cardiovascular reactivity in Africans

Sub-Saharan Africans face an increasing burden of hypertension. Although controversial, recent experimental evidence strongly suggests that serum calcium contributes to elevated blood pressure through increased vascular resistance. We investigated the associations of 24-h blood pressure and cardiovascular reactivity with serum calcium in African men stratified by age. The study consisted of 50 younger (median age: 38 years) and 49 older (median age: 49 years) participants. We measured 24-h ambulatory blood pressure with a mean successful inflation rate of 72.6%. Total peripheral resistance and stroke volume reactivity were obtained using a Finometer device during application of the Stroop color and word conflict test. Total serum calcium was adjusted for serum albumin. Results showed that serum calcium levels were similar between the younger and older groups. However, in the younger group, 24-h systolic blood pressure, 24-h diastolic blood pressure and total peripheral resistance reactivity correlated positively, whereas stroke volume reactivity correlated negatively with serum calcium in single and multiple regression analyses (systolic blood pressure: B=34.99, P=0.017; diastolic blood pressure: B=34.93, P<0.001; total peripheral resistance reactivity: B=65.44, P=0.048; stroke volume reactivity: B=−45.40, P=0.017). No associations were evident in the older African men. In conclusion, 24-h ambulatory systolic and diastolic blood pressures are positively associated with serum calcium in African men younger than 43 years. The blood pressure–serum calcium relationship seems to be mediated through increased vascular resistance during stres

Arterial stiffness, ambulatory blood pressure and low-grade albuminuria in non-diabetic African and caucasian men: the SABPA study

Official journal of the Japanese Society of HypertensionRecent evidence suggests that low-grade urinary albumin excretion is a marker of early general attenuation of vascular function, but studies are limited to Caucasian population groups. We compared low-grade urinary albumin excretion (<3.5 mg mmol−1 or 30 μg mg−1) between non-diabetic African (aged, 41.7 years; n=70) and Caucasian (aged, 44.6 years; n=91) men and ethnic-specific associations thereof with arterial stiffness and ambulatory blood pressure. The albumin-to-creatinine ratio (ACR) was determined from an 8 h overnight urine collection. We recorded ambulatory blood pressure over 24 h during a typical workday and the carotid–dorsalis pedis pulse wave velocity measured the next morning after a controlled overnight stay. ACR was higher in Africans compared with Caucasians (P<0.001), also after adjusting for 24 h systolic blood pressure, diastolic blood pressure and hypertension prevalence (P<0.001) or when grouped by similar 24 h mean arterial pressures (P<0.01 for all categories). Daytime (P=0.002) and night time (P< 0.001) systolic and daytime (P<0.001) and night time (P<0.001) diastolic blood pressures were higher in Africans compared with Caucasians, but no differences existed for daytime and night time pulse pressure and pulse wave velocity. In African men only, after adjustment for covariates, night time systolic blood pressure (β=0.347; P=0.003), diastolic blood pressure (β=0.298; P=0.010) and mean arterial pressure (β=0.331; P=0.004) correlated positively with ACR. In addition, daytime (β=0.265; P=0.032) and night time (β=0.258; P=0.038) pulse pressure as well as pulse wave velocity (β=0.271; P=0.032) correlated positively with ACR. In conclusion, arterial stiffness and ambulatory blood pressure are already associated with low-grade albuminuria in non-diabetic African men with normal kidney function