Hypertension in sub-Saharan Africa: the current profile, recent advances, gaps, and priorities.

Recent global and regional reports consistently confirm the high and increasing prevalence of hypertension in sub-Saharan Africa (SSA), with poor detection, treatment, and control rates. This narrative review summarises the burden of hypertension in SSA and recent findings from community-based hypertension management strategies. We further outline prominent risk factors according to recent data and associated underlying mechanisms for hypertension development. An extensive review of literature showed that most countries have reported on the prevalence of hypertension during 2017-2023, despite limitations linked to the lack of nationally representative studies, heterogeneity of sampling and data collection methods. Task-shifting approaches that assign roles to model patients and community health workers reported improved linkage to healthcare services and adherence to medication, with inconsistent findings on blood pressure (BP)-lowering effects over time. The regularly reported risk factors include unhealthy diet, sedentary lifestyle, increased adiposity and underweight, ageing, level of education, and/or income as well as psychosocial factors. Newer data on the pathophysiological mechanisms leading to hypertension and potential areas of intervention are reported from children and adults and include, among others, salt-handling and volume overload, endothelial function, BP dipping patterns and the role of human immunodeficiency virus . To conclude, significant strides have been made in data reporting from SSA on the burden of hypertension in the region as well as biomarker research to improve understanding and identification of areas of intervention. However, gaps remain on linkage between knowledge generation, translation, and implementation research. Coordinated studies addressing both discovery science and public health are crucial to curb hypertension development and improve management in SSA.

Food insecurity and coping strategies associate with higher risk of anxiety and depression among South African households with children.

OBJECTIVE: To investigate food insecurity and related coping strategies, and their associations with the risk of anxiety and depression, among South African households with children. DESIGN: Nationally representative cross-sectional study. Tools for assessing food insecurity, coping strategies, risk of anxiety and depression were assessed from the Community Childhood Hunger Identification Project, Coping Strategies Index, Generalised Anxiety Disorder-7 and Patient Health Questionnaire-9, respectively. We used ordered logistic regression to test associations of food insecurity and coping strategies with the risk of anxiety and depression. Moderating effects of each coping strategy were tested in the associations of food insecurity with anxiety and depression. SETTING: South Africa, post COVID-19 restrictions, May-June 2022. PARTICIPANTS: 1,774 adults, weighted to 20,955,234 households. RESULTS: Food insecurity prevalence was 23·7 % among households with children. All coping strategies were used to some extent, but relying on less preferred and less expensive foods was the most used strategy (85·5 % of food-insecure households). Moving to a higher level of food insecurity was associated with >1·6 greater odds of being in a higher risk of anxiety and depression. Sending a household member to beg for food was the strongest associated factor (OR = 1·7, P < 0·001). All coping strategies partly moderated (lessened) the associations of food insecurity with a higher risk of anxiety and depression. CONCLUSIONS: Food insecurity among households with children was high following the COVID-19 pandemic. Collaborative efforts between government, private sector and civil society to eradicate food insecurity should prioritise poorer households with children, as these populations are the most vulnerable.

Exploring the national prevalence of mental health risk, multimorbidity and the associations thereof: a repeated cross-sectional panel study.

Objective and methods: South Africans were affected by the COVID-19 pandemic and resultant economic hardships. As a result, mental health within this region may have worsened. Therefore, using large scale nationally representative data, we repeated the cross-sectional panel study to investigate mental health risk post COVID-19 to explore mental health and multimorbidity and to examine the relationship between adverse childhood experiences (ACEs) and comorbid health conditions in South African adults (aged 18 years and older). Results: Post-pandemic, 26.2, 17.0, and 14.8% of the South African respondents reported being probably depressed, anxious and had suffered high exposure to early life adversity, respectively. Nationally, the prevalence of mental health across the country remained alarmingly high when compared to Panel 1. The prevalence of multimorbidity (2 or more chronic morbidities) among the South African population was reported at 13.9%, and those with 2 or more morbidities were found to have increased odds of early adversity, irrespective of differing socio-demographics. Furthermore, early adversity was also associated with multimorbidity partly via mental health. Conclusion: This repeated cross-sectional national study reiterated that the prevalence of mental health across South African adults aged 18 years and older is widespread. Mental health remains worryingly high post-pandemic where more than a quarter of respondents are probably depressed, nearly one in every five respondents are anxious, and 14.8% reported high exposure ACEs. Public health interventions need to be upscaled with efforts to reduce the incidence of early adversity that may have the ability to lower adverse health outcomes and mental ill-health in adulthood.

Socioeconomic position, perceived weight, lifestyle risk, and multimorbidity in young adults aged 18 to 35 years: a Multi-country Study.

BACKGROUND: Multimorbidity-risk is established early in life, therefore reducing modifiable risk factors such as overweight or obesity may, in part, tackle the burden of multimorbidity in later life. METHODS: We made use of a cross-sectional online survey that included young adults (18-35yrs old) from three countries - Kenya, South Africa, and the United Kingdom (n = 3000). Information pertaining to socio-demographic, health, lifestyle, and perceived weight was collected. Additionally, the sum of affirmed morbidities was used to determine a morbidity score. Likewise, a lifestyle risk score was calculated based on information obtained from questions surrounding four unhealthy lifestyle behaviours, namely current smoking, alcohol consumption, physical inactivity, and overweight/obese weight status as a confirmed clinic condition. We further explored differences in socioeconomic position, and the prevalence of perceived weight, multimorbidity, and lifestyle risk factors between the three countries. We also determined the odds ratio of multimorbidity with perceived weight as a main predictor variable. We furthermore performed a generalised structural equation model to determine whether the association between socioeconomic position and multimorbidity was mediated via perceived weight and/or lifestyle risk. RESULTS: Socioeconomic position, weight perceptions, lifestyle risk, and multimorbidity varied significantly across the different economic countries. Higher morbidity (by > 11.9%) and lifestyle risk (by > 20.7%) scores were observed in those who reported an overweight weight perception when compared to those with an underweight or normal weight perception. In pooled analyses, the odds ratio in developing 2 or more morbidities increased multiple times in those who perceived themselves as overweight (all models: OR ≥ 2.241 [95% CI ≥ 1.693; ≥ 2.966] p < 0.001), showing a larger odds ratio with high significance in those who reported 3 or more morbidities (all models: OR ≥ 3.656 [95% CI ≥ 2.528; ≥ 5.286] p < 0.001). Furthermore, this study showed that an overweight weight perception partially mediated (p ≤ 0.001) the association between socioeconomic position and multimorbidity. CONCLUSIONS: This study confirmed poorer health outcomes in those who perceived themselves as overweight. The findings from this study further emphasise the importance of targeted intervention strategies directed at raising weight-related awareness and potentiating risk factors, specifically in those who reside in lower economic developed countries.

Early vascular ageing phenotypes and urinary targeted metabolomics in children and young adults: the ExAMIN Youth SA and African-PREDICT studies.

Some individuals are susceptible to accelerated biological ageing, resulting in premature alterations in arterial structure and function. Identifying early-onset vascular ageing characterised by arterial stiffening is vital for intervention and preventive strategies. We stratified and phenotyped healthy children (5-9 yrs) and young adults (20-30 yrs) into their vascular ageing extremes established by carotid-femoral pulse wave velocity (cfPWV) percentiles (i.e., healthy vascular ageing (HVA) and early vascular ageing (EVA)). We compared anthropometric, cardiovascular, and metabolomic profiles and explored associations between cfPWV and urinary metabolites. Children and adults in the EVA groups displayed higher levels of adiposity, cardiovascular, and lifestyle risk factors (adults only) (all p ≤ 0.018). In adults, several urinary metabolites were lower in the EVA group (all q ≤ 0.039) when compared to the HVA group, with no differences observed in children. In multiple regression analysis (adults only), we found inverse associations between cfPWV with histidine (adj. R2 = 0.038; ß = -0.192; p = 0.013) and beta-alanine (adj. R2 = 0.034; ß = -0.181; p = 0.019) in the EVA group, but with arginine (adj. R2 = 0.021; ß = -0.160; p = 0.024) in the HVA group. The inverse associations of beta-alanine and histidine with cfPWV in the EVA group is suggestive that asymptomatic young adults who present with an altered metabolomic and less desired cardiovascular profile in combination with unfavourable lifestyle behaviours may be predisposed to early-onset vascular ageing. Taken together, screening on both a phenotypic and metabolic level may prove important in the early detection, prevention, and intervention of advanced biological ageing.

The Effects of COVID-19 Pandemic Lockdowns on Alcohol Consumption and Tobacco Smoking Behaviour in South Africa: A National Survey.

INTRODUCTION: During the first phase of the coronavirus (COVID-19) pandemic lockdowns in South Africa (SA), both alcohol and tobacco were considered non-essential goods and their sales were initially prohibited and further restricted to certain days and timeframes. This study investigates self-reported changes in alcohol consumption and tobacco smoking behaviour in the general population during the COVID-19 pandemic lockdowns in SA. METHODS: A cross-sectional national survey was conducted in October 2021 (before the Omicron wave 4 and while SA was in low-level lockdown) among 3,402 nationally representative respondents (weighted to 39,640,674) aged 18 years and older. Alcohol consumption and tobacco use were assessed from the beginning of the lockdown towards the end of March 2020 until October 2021 using the WHO-AUDIT and the US Centre for Disease Control (CDC) Global Adult Tobacco Survey questionnaires, respectively. RESULTS: Among those that drank alcohol (33.2%), 31.4% were classified as having a drinking problem that could be hazardous or harmful and 18.9% had severe alcohol use disorder during the COVID-19 lockdowns. Twenty-two per cent (22.0%) of those that reported alcohol consumption reported that the COVID-19 pandemic lockdowns changed their alcohol consumption habits, with 38.1% reporting a decreased intake or quitting altogether. Among the one in five respondents (19.2%) who had ever smoked, most reported smoking at the time of the survey (82.6%) with many classified as light smokers (87.8%; ≤10 cigarettes/day). Almost a third (27.2%) of those smoking reported that the COVID-19 pandemic lockdowns had changed their use of tobacco products or vaping, with 60.0% reporting a reduction/quitting tobacco use. Given that sales were restricted this indicates that people could still get hold of tobacco products. Heavy smoking was associated with older age (p = 0.02), those classified as wealthy (p < 0.001), those who started or increased tobacco smoking during the pandemic lockdowns (p = 0.01) and residential provinces (p = 0.04). CONCLUSION: Given restrictions on the sale of alcohol and tobacco in SA between 27 March and August 17, 2020, during the pandemic, respondents reported an overall decline in alcohol consumption and tobacco use which might suggest that the regulatory restrictive strategies on sales had some effect but may be inadequate, especially during times where individuals are likely to experience high-stress levels. These changes in alcohol consumption and tobacco use were different from what was reported in several European countries, possibly due to differences in the restrictions imposed in SA when compared to these European countries.

Drivers of disparities in stage at diagnosis among women with breast cancer: South African breast cancers and HIV outcomes cohort.

OBJECTIVE: In low- and middle-income countries (LMICs), advanced-stage diagnosis of breast cancer (BC) is common, and this contributes to poor survival. Understanding the determinants of the stage at diagnosis will aid in designing interventions to downstage disease and improve survival from BC in LMICs. METHODS: Within the South African Breast Cancers and HIV Outcomes (SABCHO) cohort, we examined factors affecting the stage at diagnosis of histologically confirmed invasive breast cancer at five tertiary hospitals in South Africa (SA). The stage was assessed clinically. To examine the associations of the modifiable health system, socio-economic/household and non-modifiable individual factors, hierarchical multivariable logistic regression with odds of late-stage at diagnosis (stage III-IV), was used. RESULTS: The majority (59%) of the included 3497 women were diagnosed with late-stage BC disease. The effect of health system-level factors on late-stage BC diagnosis was consistent and significant even when adjusted for both socio-economic- and individual-level factors. Women diagnosed in a tertiary hospital that predominantly serves a rural population were 3 times (OR = 2.89 (95% CI: 1.40-5.97) as likely to be associated with late-stage BC diagnosis when compared to those diagnosed at a hospital that predominantly serves an urban population. Taking more than 3 months from identifying the BC problem to the first health system entry (OR = 1.66 (95% CI: 1.38-2.00)), and having luminal B (OR = 1.49 (95% CI: 1.19-1.87)) or HER2-enriched (OR = 1.64 (95% CI: 1.16-2.32)) molecular subtype as compared to luminal A, were associated with a late-stage diagnosis. Whilst having a higher socio-economic level (a wealth index of 5) reduced the probability of late-stage BC at diagnosis, (OR = 0.64 (95% CI: 0.47-0.85)). CONCLUSION: Advanced-stage diagnosis of BC among women in SA who access health services through the public health system was associated with both modifiable health system-level factors and non-modifiable individual-level factors. These may be considered as elements in interventions to reduce the time to diagnosis of breast cancer in women.

Association between socio-economic status and non-communicable disease risk in young adults from Kenya, South Africa, and the United Kingdom.

There is a pressing need for global health preventions to curb the escalating burden of non-communicable diseases (NCDs). Utilising multi-country study designs can improve our understanding of how socio-economic context shapes the aetiology of NCDs, and this has great potential to advance global health interventions. We examined the association between socio-economic status (SES) and NCD risk, and the potential confounding effects of smoking and alcohol intake in young adults (18-35-year-olds) from Kenya, South Africa (SA), and the United Kingdom (UK). Our study was a cross-sectional online survey that included 3000 respondents (n = 1000 per country, 50% women) conducted in April 2022. We utilised information on twelve NCDs to classify respondents as having "no condition", "one condition", and "multimorbidity" (having two or more conditions). A total household asset score was calculated and used as a proxy of SES, and subsequently categorised into quintiles (Q1-Q5; lowest-highest). Ordered logistic regression was used to test the associations between NCD risk and exposure variables. In the UK sample, we found that those in the second lowest SES quintile (Q2) had lower odds of developing NCDs than their lowest SES counterparts (Q1). In contrast, South African and Kenyan youth with a SES score between middle and highest quintiles (Q3-Q5) were more likely to develop NCDs than the lowest SES quintile group. In all countries, smoking and/or alcohol intake were associated with higher odds of developing NCDs, and showed some confounding effects on the SES-NCD relationships. Specifically, in Kenya, the risk of developing NCD was more than two times higher in those in the middle (Q3) SES group (OR 2.493; 95% CI 1.519-4.091; p < 0.001) compared to their lowest (Q1) SES counterparts. After adjusting for smoking and alcohol, the ORs of middle (Q3) SES group changed from 2.493 to 2.241 (1.360-3.721; p = 0.002). Overall, we found that the strength and direction of SES-NCD associations differed within and between countries. This study highlights how different SES contexts shape the risk of NCDs among young adults residing in countries at different levels of economic development.

Food insecurity and coping strategies and their association with anxiety and depression: a nationally representative South African survey.

OBJECTIVE: To investigate food insecurity and related coping strategies among South African households and their associations with anxiety and depression. DESIGN: Cross-sectional study. Food insecurity and coping strategies were assessed using a modified Community Childhood Hunger Identification Project and the Coping Strategies Index questionnaires. The Generalized Anxiety Disorder-7 and Patient Health Questionnaire-9 were used to assess anxiety and depression risk. Ordered logistic regressions were used to test associations of food insecurity and related coping strategies with anxiety and depression. SETTING: South Africa during COVID-19, October 2021. PARTICIPANTS: Nationally representative sample of 3402 adults, weighted to 39,640,674 South African households. RESULTS: About 20·4 % of South African households were food insecure, with the most affected being from the lowest socio-economic groups. Shifting from 'food secure' to 'at risk' or from 'at risk' to 'food insecure' group was associated with 1·7 times greater odds of being in a higher category of anxiety or depression (P < 0·001). All coping strategies were used to some extent in South African households, with 46·0 % relying on less preferred and less expensive foods and 20·9 % sending a household member to beg for food. These coping strategies were mostly used by food-insecure households. Although the odds of moving to a higher category of anxiety and depression were observed among all coping strategies (all P < 0·001), begging for food was associated with the highest odds (OR = 2·3). CONCLUSIONS: Food insecurity remains a major health threat in South Africa. Public measures to address mental health should consider reductions in food insecurity as part of their strategy.

The prevalence of probable depression and probable anxiety, and associations with adverse childhood experiences and socio-demographics: A national survey in South Africa.

Objective and methods: Mental health problems among adults are a growing public health concern, and middle-income countries such as South Africa are disproportionally affected. Using a large scale nationally representative weighted survey, we assessed the prevalence of probable depression, probable anxiety, and adverse childhood experiences (ACEs), and explored associations between probable depression, probable anxiety, ACEs, socio-economic status, and demographic characteristics. Results: Nationally, 25.7, 17.8, and 23.6% of respondents, respectively, reported scores of ≥10 on the Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7), indicating probable depression or probable anxiety, and an ACE score of ≥4 (high exposure). Overall probable depression prevalence across South Africa varied from 14.7 to 38.8%. Both probable depression and probable anxiety were more frequently reported among adults who were: retired and older (>65 years of age), and widowed, divorced, or separated; living in metropolitan areas; and only had primary school education. In a multivariable adjusted logistic regression, the likelihood of reporting probable depression or probable anxiety was also found to increase with each standard deviation increase in the ACE score (p < 0.001), independent of other socio-demographic determinants. Conclusion: The prevalence of probable depression among respondents in South Africa varies significantly across the nine provinces. Furthermore, higher ACE score and several socio-demographic determinants were associated with a higher likelihood of probable depression and probable anxiety. Adult mental health services are urgently needed to identify groups of the population vulnerable to mental health problems for better targeting of interventions. Given the range of probable depression prevalence across the country, provincial level plans and resources should also reflect the burden of mental health problems in that province.

Social vulnerability and its association with food insecurity in the South African population: findings from a National Survey.

Social vulnerability refers to the attributes of society that make people and places susceptible to natural disasters, adverse health outcomes, and social inequalities. Using a social vulnerability index (SVI), we investigated social vulnerability prevalence and its relationship with food insecurity in South Africa (SA). In this nationally representative cross-sectional survey, we calculated SVI scores from 3402 respondents (median age, 35 (26-46) years) using an SVI developed by the United States (US) Centers for Disease Control and prevention (CDC) adapted for a South African context. We measured food insecurity using a modified Community Childhood Hunger Identification Project. Findings classified 20.6% and 20.4% of adults as socially vulnerable and food insecure, respectively. The risk of food insecurity was almost threefold higher in the social vulnerability group (OR 2.76, 95% CI 2.76-2.77, p < 0.001) compared to their counterparts. The SVI could be a useful tool to guide government and policymakers in the facilitation of social relief initiatives for those most vulnerable.

Prevalence of multimorbidity in men of African descent with and without prostate cancer in Soweto, South Africa.

OBJECTIVE: With increases in chronic disease, men with prostate cancer are likely to have at least one other chronic health condition. The burden and complexity of each additional chronic disease may complicate prostate cancer treatment and reduce survival. In this paper, we describe the frequency of multimorbid chronic diseases, HIV and depression among men in Soweto, South Africa (SA) with and without prostate cancer and determine whether the presence of multimorbid diseases is associated with metastatic and high-risk, non-metastatic prostate cancer. METHODS: A population-based case-control study on prostate cancer was conducted among black men in Soweto. All participants completed a baseline survey on sociodemographics, lifestyle, and comorbid medical conditions. All participants completed a depression screening survey and HIV testing at enrolment. Blood pressure measurements and blood testing for fasting glucose, total cholesterol, and high-density lipoprotein were performed on a subset of randomly selected cases and controls. For men with prostate cancer, clinical T staging was assessed with the digital rectal examination, the diagnosis was confirmed with a biopsy and PSA levels were assessed at presentation. The metastatic staging was assessed by bone scans, and this was confirmed with PSMA PET scans, CT scans and X-rays, standard for our resource-constrained setting. Normal PSA scores were used as an inclusion criterion for controls. RESULTS: Of the 2136 men (1095 with prostate cancer and 1041 controls) included in the analysis, 43.0% reported at least one chronic metabolic disease; 24.1% reported two metabolic diseases; 5.3% reported three metabolic diseases; and 0.3% reported four metabolic diseases. Men with prostate cancer were more likely to report a multimorbid chronic metabolic disease compared to controls (p<0.001) and more likely to test positive for HIV (p = 0.05). The majority of men (66.2%) reported at least one metabolic disease, tested negative for HIV and had a negative depression screen. The clinical characteristics of men with prostate cancer, were as follows: 396 (36.2%) had a Gleason score of 8 and above; 552 (51.3%) had a PSA score of >20ng/ml; 233 (21.7%) had confirmed metastatic prostate cancer at diagnosis. Older age was associated with metastatic prostate cancer (OR = 1.043 95% CI:1.02-1.07) and NCCN defined high-risk non-metastatic prostate cancer (OR = 1.03 95% CI:1.01-1.05), whilst being hypertensive was protective (OR = 0.63 95% CI:0.47-0.84 and OR = 0.55 95% CI:0.37-0.83) respectively for metastatic and high-risk, non-metastatic prostate cancer. CONCLUSION: The high prevalence of multimorbid metabolic diseases and HIV among men with prostate cancer represents a public health concern in South Africa. There is a need to effectively address multiple chronic diseases among men with prostate cancer by incorporating coordinated care models.

Determining Underlying Mechanisms of Early Vascular Ageing by Clustered Analysis: The African-PREDICT Study.

OBJECTIVE: Identifying individuals at increased risk of early vascular ageing (EVA) is paramount to inform intervention and prevention strategies and curb the increasing burden of cardiovascular disease. METHODS: We stratified and phenotyped pre-screened young apparently healthy South African adults (20-30 yrs) (n=1,041) into vascular ageing profile groups based on carotid femoral pulse wave velocity (cfPWV) percentiles (healthy vascular ageing [HVA]; average vascular ageing [AVA] and EVA). We further compared various anthropometric, cardiovascular (CV), oxidative stress and lifestyle risk factors and determined factor scores to explore associations between CV measures and factor clusters to explore associations in those at risk of EVA. RESULTS: Young adults in the EVA group displayed marked phenotypic characteristics in terms of anthropometry, CV, and lifestyle risk factors, even though cfPWV were within healthy ranges. Blood pressure (brachial and central) and cfPWV were all incrementally higher across all three vascular ageing groups (p-trend ≤0.011). Hypertension, lifestyle risk factors such as self-reported smoking and alcohol consumption were all highest in the EVA group (p-trend ≤0.046). Additionally, in the EVA group only, cfPWV (adj. R2=0.028; ß=0.171; p=0.042) associated positively with Factor 2 (oxidative stress and antioxidant capacity). No associations existed between Factor 1 (basic lipids) and any anthropometric or CV measures (p>0.050). CONCLUSION: Young adults with higher cfPWV presented with a less favourable vascular profile and more unhealthy lifestyle behaviours compared to groups with lower cfPWV. In the EVA group, cfPWV positively associated with a cluster of oxidative stress and antioxidant capacity. Early lifestyle behaviours may have the ability to modify the balance between oxidants and antioxidants, potentially contributing to early onset arterial stiffness.

Elevated blood pressure positively associates with alpha-1 microglobulin in prepubescent children: the ExAMIN Youth SA study.

OBJECTIVES AND METHODS: Hypertension is a growing health concern in childhood populations and individuals of African descent. As the kidneys play a significant role in blood pressure regulation, we compared alpha-1 microglobulin (A1M) as a marker of proximal tubular function between young healthy black and white children (n = 957; aged: 5-9 years) and explored its association with blood pressure. RESULTS: The black children had higher levels of A1M (P < 0.001) and higher DBP (P < 0.001) when compared with their white counterparts. In multiple regression analysis, SBP (adj. R2 = 0.173, ß = 0.151; P < 0.001) and DBP (adj. R2 = 0.110, ß = 0.179; P < 0.001) associated positively with A1M in the black children. In binary logistic regression, each standard deviation increase in A1M increased the odds of having elevated blood pressure by 28% (P = 0.002) in the black group, independent of age, sex, BMI z-score and body height. No significance was reached in the white children. CONCLUSION: Our findings highlight the importance of a marker of proximal tubular function, especially in children of black ethnicity, in the setting of elevated blood pressure. Early childhood screening for elevated blood pressure remains essential in order to promote primary prevention of hypertension and early onset kidney damage in children.

Urinary albumin-to-creatinine ratio is inversely related to nitric oxide synthesis in young black adults: the African-PREDICT study.

Hypertension is common in black populations and is known to be associated with low nitric oxide (NO) bioavailability. We compared plasma and urinary NO-related markers and plasma creatine kinase (CK) levels between young healthy black and white adults along with the associations of these markers with the urinary albumin-to-creatinine ratio (uACR), which is a surrogate marker of endothelial and kidney function. We included 1105 participants (20-30 years). We measured the uACR, plasma CK, plasma and urinary arginine, homoarginine, asymmetric (ADMA) and symmetric dimethylarginine (SDMA), urinary ornithine/citrulline, nitrate and nitrite, and malondialdehyde (MDA). In addition, the urinary nitrate-to-nitrite ratio (UNOxR) was calculated and used as a measure of circulating NO bioavailability. The uACR was comparable between the groups, yet the black group had lower urinary nitrate (by -15%) and UNOxR values (by -18%) (both p ≤ 0.001), higher plasma (by +9.6%) and urinary (by +5.9%) arginine (both p ≤ 0.004), higher plasma (by +13%) and urinary (by +3.7%) ADMA (both p ≤ 0.033), and higher CK (by +9.5%) and MDA (by +19%) (both p < 0.001) compared with white adults. Plasma and urinary homoarginine were similar between the groups. In the multiple regression analysis, we confirmed the inverse associations of the uACR with both plasma (adj. R2 = 0.066; ß = -0.209; p = 0.005) and urinary (adj. R2 = 0.066; ß = -0.149; p = 0.010) homoarginine and with the UNOxR (adj. R2 = 0.060; ß = -0.122; p = 0.031) in the black group only. The overall less favorable NO profile and higher CK and MDA levels in the black cohort along with the adverse associations with the uACR may reflect the vulnerability of this cohort to the early development of hypertension.

Cross-Talk Between Large Artery Stiffness and Retinal Microvasculature in Children: The ExAMIN Youth SA Study.

Background: Cross-talk between the macro-and microvasculature is considered an important contributor to target organ damage. Previous findings were predominantly in adult populations and investigation into this mechanism in children may provide insight into the development of early adverse vascular changes. Whether any ethnic differences in cross-talk is evident, also remains to be determined. Objective: To determine whether retinal microvascular diameters are associated with large artery stiffness in young children and whether ethnic differences are evident. Materials and Methods: In this cross-sectional study, 730 black (n = 437) and white (n = 293) school children aged 5-9 years were included. Pulse wave velocity (PWV) was measured and the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) diameters were calculated from fundus images. The arterio-venous ratio (AVR) was subsequently calculated. Results: Pulse wave velocity was lower (p ≤ 0.001) in the black group when compared to the white group. The black group had a narrower CRAE, wider CRVE and lower AVR (all p < 0.001). Pulse wave velocity associated negatively with CRAE (r = -0.141, p = 0.003) and AVR (r = -0.185, p ≤ 0.001) in the black group only. A positive association between PWV and CRVE was seen in the black (r = 0.174, p ≤ 0.001) and white (r = 0.119, p = 0.043) group. Conclusion: Large artery stiffness is associated with retinal arterial narrowing and venular widening in children, suggesting cross-talk between the macro-and microvasculature. Ethnic differences in these associations are also evident. Our findings warrant further investigation into environmental and sociocultural risk factors contributing to premature cardiovascular disease development.

Central systolic blood pressure relates inversely to nitric oxide synthesis in young black adults: the African-PREDICT study.

Lower nitric oxide (NO) bioavailabilty associates with hypertension in patients and elderly populations. With hypertension known to develop earlier in black populations, we compared both plasma and urinary NO-related markers and their associations with central systolic blood pressure (cSBP) and arterial stiffness in healthy young black and white adults. We included healthy black and white men and women (n = 1110; 20-30 years) and measured cSBP and pulse wave velocity (PWV), along with both plasma and urinary arginine, homoarginine, asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), as well as urinary ornithine/citrulline, nitrite and nitrate. In addition, the urinary nitrate-to-nitrite ratio (UNOxR) was calculated. The black men and women had higher cSBP and higher plasma arginine and ADMA, but lower urinary nitrate and UNOxR (all p ≤ 0.003) than their white counterparts. In single and forward stepwise multiple regression analyses, we found an inverse association of cSBP (adj. R2 = 0.124; ß = -0.134; p = 0.006) and plasma homoarginine in black men. Central SBP associated inversely with UNOxR in black women only (adj. R2 = 0.171; ß = -0.130; p = 0.029). In the white women, cSBP associated positively with urinary ADMA (adj. R2 = 0.372; ß = 0.162; p = 0.015). PWV associated inversely with plasma ADMA (adj. R2 = 0.253; ß = -0.163; p = 0.024) in the white women only. The lower NO synthesis and the higher cSBP in our black cohort support the notion of a potential increased risk for future large artery stiffness and hypertension development in later life.

Nitric oxide-related markers link inversely to blood pressure in black boys and men: the ASOS and African-PREDICT studies.

Nitric oxide plays an important role in maintaining endothelial function, while increased oxidative stress may lead to nitric oxide inactivation and cardiovascular disease. If nitric oxide biosynthesis/bioavailability is already suppressed early in life, it may potentially predispose an individual to the early development of cardiovascular disease. We therefore aimed to identify differences in nitric oxide-related markers (urinary nitrate, nitrite and the nitrate-to-nitrite ratio (UNOxR)) between young black and white individuals, and whether these markers are associated with blood pressure and carotid intima media thickness. We included black and white healthy boys (n = 80; aged 6-8 years) and men (n = 510; 20-30 years) and measured blood pressure and carotid intima media thickness, along with urinary biochemical markers including nitrate and nitrite. The black boys and men had lower nitrate and UNOxR (all p ≤ 0.003) than their white counterparts. In single and multiple regression analyses, we found an inverse association of diastolic blood pressure in the black boys (adj. R2 = 0.27; ß = -0.32; p = 0.030), and systolic blood pressure in black men (adj. R2 = 0.07; ß = -0.13; p = 0.036) with nitrate. Carotid intima media thickness associated inversely with UNOxR in the black men (adj. R2 = 0.02; ß = -0.14; p = 0.023), but not in the boys. Lower urinary nitrate in black boys and young men was associated negatively with blood pressure, suggesting that potentially lower nitric oxide bioavailability in young black individuals may contribute to hypertension development in later life.

Thiobarbituric acid-reactive substances relate to arterial stiffness and blood pressure in 6 to 8-year-old boys stratified by maternal risk.

Early cardiovascular disease (CVD) onset can be inflicted by familial cardiovascular and lifestyle risk factors. We aimed to compare phenotypic characteristics and explore associations between oxidative stress and vascular function in boys stratified by maternal cardiovascular and lifestyle risk. We included 40 Black and 41 White boys (ages 6-8 years), along with the biological mother of each child. The study population was divided into two groups (nonmaternal risk vs. maternal risk) according to maternal risk predetermined by their selfreported cardiovascular and lifestyle risk factors. Pulse wave velocity (PWV) was measured at various sites and blood pressures were recorded. Urine samples were collected for analyses of thiobarbituric acid-reactive substances (TBARS), 8-hydroxy-2-deoxy guanosine (8-OHdG), albumin, and creatinine. Higher levels of urinary albumin to creatinine ratio (uACR) were found in the maternal risk group compared to the nonmaternal risk group (p = .038). Multiple regression analysis in the maternal risk group revealed diastolic blood pressure (R2 = 0.159; ß = 0.293; p = .050), carotid femoral PWV (R2 = 0.158; ß = 0.297; p = .038) and carotid dorsalis pedis PWV (adj R2 = 0.322; ß = 0.505; p < .001) to be positively associated with TBARS, while an inverse association of uACR (R2 = 0.161; ß = -0.261; p = .046) with TBARS was observed. Also, in the maternal risk group, independent associations of DBP (R2 = 0.273; ß = 0.289; p = .040) and uACR (R2 = 0.283; ß = 0.268; p = .027) with 8-OHdG were indicated. In boys, as young as 6 years of age, oxidative stress related to arterial stiffness and diastolic blood pressure was observed. This association was only evident in boys with linked maternal lifestyle and cardiovascular risk factors, suggesting potential family-related early onset of cardiovascular risk.