Waist-to-height ratio is a useful indicator of cardio-metabolic risk in South Africa.

BACKGROUND: The use of waist-to-height ratio has been suggested as a better proxy indicator of central obesity. OBJECTIVE: To compare the utility of waist-to-height ratio with commonly used adiposity indices of body mass index, waist circumference and waist-to-hip ratio to identify cardio-metabolic diseases in 25-74-year-old black residents of Cape Town. METHODS: This cross-sectional study, stratified for age and gender, determined cardio-metabolic abnormalities by administered questionnaires, clinical measurements and biochemical analyses, including oral glucose tolerance tests. Correlations between adiposity indices with cardio-metabolic components were examined. Age- and gender-adjusted logistic regression analyses determined the associations of obesity by these adiposity indices with cardio-metabolic abnormalities. RESULTS: The study comprised 392 men and 707 women. Compared with other adiposity indices, waist-to-height ratio in men correlated most closely with fasting (0.360) and 2-hour (0.388) glucose levels, total cholesterol (0.267), low-density lipoprotein cholesterol (0.351) and triglycerides (0.400). In women, waist-to-height ratio correlated the best with systolic blood pressure (0.254) and diastolic blood pressure (0.287). Of the adiposity indices, waist circumference was most strongly associated with diabetes (odds ratio 4.27, 95% confidence interval: 2.39-7.62), low high-density lipoprotein cholesterol (2.84, 1.90-4.26) and hypertriglyceridaemia (3.60, 2.03-6.40), whereas raised waist-to-height ratio was most closely related to hypertension (1.61, 1.07-2.42), hypercholesterolaemia (1.72, 1.04-2.83) and raised low-density lipoprotein cholesterol (2.46, 1.70-3.55). CONCLUSIONS: Compared with other adiposity indices, the better correlation of waist-to-height ratio with many cardio-metabolic components, particularly in men, and the stronger association of raised waist-to-height ratio with hypertension, hypercholesterolaemia and raised low-density lipoprotein cholesterol support the utility of waist-to-height ratio in routine assessments of adiposity in this population, which may improve the identification of cardio-metabolic risk.

Prevalence, concordance and associations of chronic kidney disease by five estimators in South Africa.

BACKGROUND: To determine the prevalence, distribution, concordance and associations of chronic kidney disease (CKD) determined by five glomerular filtration rate (GFR) formulae in urban black residents of Cape Town. METHODS: Data collection in this cross-sectional study included interviews, clinical measurements and biochemical analyses, including serum creatinine and cystatin C levels. GFR was based on the CKD Epidemiology Collaboration (CKD-EPI) equations (CKD-EPI creatinine (CKD-EPIcr), CKD-EPI cystatin C (CKD-EPIcys), CKD-EPI creatinine-cystatins (CKD-EPIcr-cys)), Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault formula (CGF). GFR < 60 mL/min/1.73 m2 defined CKD. RESULTS: Among 392 men and 700 women, mean GFR, was between 114.0 (CKD-EPIcr) and 135.4 mL/min/1.73 m2 (CGF) in men, and between 107.5 (CKD-EPIcr-cys) and 173.4 mL/min/1.73 m2 (CGF) in women. CKD prevalence ranged from 2.3% (CKD-EPIcr and MDRD) to 5.1% (CKD-EPIcys) in men and 1.6% (CGF) to 6.7% (CKD-EPIcr-cys) in women. The kappa statistic was high between CKD-EPIcr and MDRD (0.934), and CKD-EPIcys and CKD-EPIcr-cys (0.815), but fair-to-moderate between the other eqs. (0.353-0.565). In the basic regressions, older age and body mass index ≥30 kg/m2, but not gender, were significantly associated with CKD-EPIcr-defined CKD. In the presence of these three variables, hypertension, heart rate ≥ 90 beats/minute, diabetes and low-density lipoprotein cholesterol were significant predictors of prevalent CKD. CONCLUSIONS: Varying CKD prevalence estimates, because of different GFR equations used, underscores the need to improve accuracy of CKD diagnoses. Furthermore, screening for CKD should be incorporated into the routine assessment of high-risk patients such as those with hypertension or diabetes.

Monitoring the South African population's salt intake: spot urine v. 24 h urine.

OBJECTIVE: The present study set out to determine whether morning spot urine samples can be used to monitor Na (and K) intake levels in South Africa, instead of the 'gold standard' 24 h urine sample. DESIGN: Participants collected one 24 h and one spot urine sample for Na and K analysis, after which estimations using three different formulas (Kawasaki, Tanaka and INTERSALT) were calculated. SETTING: Between 2013 and 2015, urine samples were collected from different population groups in South Africa. SUBJECTS: A total of 681 spot and 24 h urine samples were collected from white (n 259), black (n 315) and Indian (n 107) subgroups, mostly women. RESULTS: The Kawasaki and the Tanaka formulas showed significantly higher (P≤0·001) estimated Na values than the measured 24 h excretion in the whole population (5677·79 and 4235·05 v. 3279·19 mg/d). The INTERSALT formula did not differ from the measured 24 h excretion for the whole population. The Kawasaki formula seemed to overestimate Na excretion in all subgroups tested and also showed the highest degree of bias (-2242 mg/d, 95 % CI-10 659, 6175) compared with the INTERSALT formula, which had the lowest bias (161 mg/d, 95 % CI-4038, 4360). CONCLUSIONS: Estimations of Na excretion by the three formulas should be used with caution when reporting on Na intake levels. More research is needed to validate and develop a specific formula for the South African context with its different population groups. The WHO's recommendation of using 24 h urine collection until more studies are carried out is still supported.

Mobile Phone Text Messages to Support Treatment Adherence in Adults With High Blood Pressure (SMS-Text Adherence Support [StAR]): A Single-Blind, Randomized Trial.

BACKGROUND: We assessed the effect of automated treatment adherence support delivered via mobile phone short message system (SMS) text messages on blood pressure. METHODS AND RESULTS: In this pragmatic, single-blind, 3-arm, randomized trial (SMS-Text Adherence Support [StAR]) undertaken in South Africa, patients treated for high blood pressure were randomly allocated in a 1:1:1 ratio to information only, interactive SMS text messaging, or usual care. The primary outcome was change in systolic blood pressure at 12 months from baseline measured with a validated oscillometric device. All trial staff were masked to treatment allocation. Analyses were intention to treat. Between June 26, 2012, and November 23, 2012, 1372 participants were randomized to receive information-only SMS text messages (n=457), interactive SMS text messages (n=458), or usual care (n=457). Primary outcome data were available for 1256 participants (92%). At 12 months, the mean adjusted change in systolic blood pressure compared with usual care was -2.2 mm Hg (95% confidence interval, -4.4 to -0.04) with information-only SMS and -1.6 mm Hg (95% confidence interval, -3.7 to 0.6) with interactive SMS. Odds ratios for the proportion of participants with a blood pressure <140/90 mm Hg were 1.42 (95% confidence interval, 1.03-1.95) for information-only messaging and 1.41 (95% confidence interval, 1.02-1.95) for interactive messaging compared with usual care. CONCLUSIONS: In this randomized trial of an automated adherence support program delivered by SMS text message in a general outpatient population of adults with high blood pressure, we found a small reduction in systolic blood pressure control compared with usual care at 12 months. There was no evidence that an interactive intervention increased this effect. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02019823. South African National Clinical Trials Register, number SANCTR DOH-27-1212-386; Pan Africa Trial Register, number PACTR201411000724141.

Educational Outreach with an Integrated Clinical Tool for Nurse-Led Non-communicable Chronic Disease Management in Primary Care in South Africa: A Pragmatic Cluster Randomised Controlled Trial.

BACKGROUND: In many low-income countries, care for patients with non-communicable diseases (NCDs) and mental health conditions is provided by nurses. The benefits of nurse substitution and supplementation in NCD care in high-income settings are well recognised, but evidence from low- and middle-income countries is limited. Primary Care 101 (PC101) is a programme designed to support and expand nurses' role in NCD care, comprising educational outreach to nurses and a clinical management tool with enhanced prescribing provisions. We evaluated the effect of the programme on primary care nurses' capacity to manage NCDs. METHODS AND FINDINGS: In a cluster randomised controlled trial design, 38 public sector primary care clinics in the Western Cape Province, South Africa, were randomised. Nurses in the intervention clinics were trained to use the PC101 management tool during educational outreach sessions delivered by health department trainers and were authorised to prescribe an expanded range of drugs for several NCDs. Control clinics continued use of the Practical Approach to Lung Health and HIV/AIDS in South Africa (PALSA PLUS) management tool and usual training. Patients attending these clinics with one or more of hypertension (3,227), diabetes (1,842), chronic respiratory disease (1,157) or who screened positive for depression (2,466), totalling 4,393 patients, were enrolled between 28 March 2011 and 10 November 2011. Primary outcomes were treatment intensification in the hypertension, diabetes, and chronic respiratory disease cohorts, defined as the proportion of patients in whom treatment was escalated during follow-up over 14 mo, and case detection in the depression cohort. Primary outcome data were analysed for 2,110 (97%) intervention and 2,170 (97%) control group patients. Treatment intensification rates in intervention clinics were not superior to those in the control clinics (hypertension: 44% in the intervention group versus 40% in the control group, risk ratio [RR] 1.08 [95% CI 0.94 to 1.24; p = 0.252]; diabetes: 57% versus 50%, RR 1.10 [0.97 to 1.24; p = 0.126]; chronic respiratory disease: 14% versus 12%, RR 1.08 [0.75 to 1.55; p = 0.674]), nor was case detection of depression (18% versus 24%, RR 0.76 [0.53 to 1.10; p = 0.142]). No adverse effects of the nurses' expanded scope of practice were observed. Limitations of the study include dependence on self-reported diagnoses for inclusion in the patient cohorts, limited data on uptake of PC101 by users, reliance on process outcomes, and insufficient resources to measure important health outcomes, such as HbA1c, at follow-up. CONCLUSIONS: Educational outreach to primary care nurses to train them in the use of a management tool involving an expanded role in managing NCDs was feasible and safe but was not associated with treatment intensification or improved case detection for index diseases. This notwithstanding, the intervention, with adjustments to improve its effectiveness, has been adopted for implementation in primary care clinics throughout South Africa. TRIAL REGISTRATION: The trial is registered with Current Controlled Trials (ISRCTN20283604).

Socioeconomic predictors and consequences of depression among primary care attenders with non-communicable diseases in the Western Cape, South Africa: cohort study within a randomised trial.

BACKGROUND: Socioeconomic predictors and consequences of depression and its treatment were investigated in 4393 adults with specified non-communicable diseases attending 38 public sector primary care clinics in the Eden and Overberg districts of the Western Cape, South Africa. METHODS: Participants were interviewed at baseline in 2011 and 14 months later, as part of a randomised controlled trial of a guideline-based intervention to improve diagnosis and management of chronic diseases. The 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) was used to assess depression symptoms, with higher scores representing more depressed mood. RESULTS: Higher CESD-10 scores at baseline were independently associated with being less educated (p = 0.004) and having lower income (p = 0.003). CESD-10 scores at follow-up were higher in participants with less education (p = 0.010) or receiving welfare grants (p = 0.007) independent of their baseline scores. Participants with CESD-10 scores of ten or more at baseline (56 % of all participants) had 25 % higher odds of being unemployed at follow-up (p = 0.016), independently of baseline CESD-10 score and treatment status. Among participants with baseline CESD-10 scores of ten or more, antidepressant medication at baseline was independently more likely in participants who had more education (p = 0.002), higher income (p < 0.001), or were unemployed (p = 0.001). Antidepressant medication at follow up was independently more likely in participants with higher income (p = 0.023), and in clinics with better access to pharmacists (p = 0.053) and off-site drug delivery (p = 0.013). CONCLUSIONS: Socioeconomic disadvantage appears to be both a cause and consequence of depression, and may also be a barrier to treatment. There are opportunities for improving the prevention, diagnosis and treatment of depression in primary care in inequitable middle income countries like South Africa. TRIAL REGISTRATION: The trial is registered with Current Controlled Trials ( ISRCTN20283604 ).

A qualitative study of the experiences of care and motivation for effective self-management among diabetic and hypertensive patients attending public sector primary health care services in South Africa.

BACKGROUND: Diabetes and hypertension constitute a significant and growing burden of disease in South Africa. Presently, few patients are achieving adequate levels of control. In an effort to improve outcomes, the Department of Health is proposing a shift to a patient-centred model of chronic care, which empowers patients to play an active role in self-management by enhancing their knowledge, motivation and skills. The aim of this study was to explore patients' current experiences of chronic care, as well as their motivation and capacity for self-management and lifestyle change. METHODS: The study involved 22 individual, qualitative interviews with a purposive sample of hypertensive and diabetic patients attending three public sector community health centres in Cape Town. Participants were a mix of Xhosa and Afrikaans speaking patients and were of low socio-economic status. RESULTS: The concepts of relatedness, competency and autonomy from Self Determination Theory proved valuable in exploring patients' perspectives on what a patient-centred model of care may mean and what they needed from their healthcare providers. Overall, the findings of this study indicate that patients experience multiple impediments to effective self-management and behaviour change, including poor health literacy, a lack of self-efficacy and perceived social support. With some exceptions, the majority of patients reported not having received adequate information; counselling or autonomy support from their healthcare providers. Their experiences suggests that the current approach to chronic care largely fails to meet patients' motivation needs, leaving many of them feeling anxious about their state of health and frustrated with the quality of their care. CONCLUSIONS: In accordance with other similar studies, most of the hypertensive and diabetic patients interviewed for this study were found to be ill equipped to play an active and empowered role in self-care. It was clear that patients desire greater assistance and support from their healthcare providers. In order to enable healthcare providers in South Africa to adopt a more patient-centred approach and to better assist and motivate patients to become effective partners in their care, training, resources and tools are needed. In addition, providers need to be supported by policy and organisational change.

Differential patterns of tobacco use among black men and women in Cape Town: the cardiovascular risk in black South Africans study.

INTRODUCTION: To examine the prevalence and determinants of tobacco use in the 25-74-year-old urban Black population of Cape Town and to examine the changes between 1990 and 2008-2009 in the 25-64-year-old sample. METHODS: In 2008-2009 (n = 1,099), a representative cross-sectional sample was randomly selected from the same townships sampled in 1990 (n = 986). Sociodemographic characteristics, tobacco use by the World Health Organization (WHO) STEP-wise questionnaire, and psychosocial stress, including sense of coherence (SOC), locus of control, and adverse life events, were determined. Survey logistic regression analysis assessed the determinants of smoking ≥ 1 cigarette/day. RESULTS: There were 392 men and 707 women. Age-standardized prevalence of smoking ≥ 1 cigarette/day was 48.5% (95% confidence interval [CI] = 43.0-54.0) in men and 7.8% (95% CI = 5.8-10.5) in women (p < .001). Prevalence in men was lower in 2008-2009 (51.0%, 95% CI = 45.2-56.7) compared with 1990 (59.7%, 95% CI = 53.8-65.4) but unchanged in women (2008/09: 8.0%, 95% CI = 5.9-10.7; 1990: 8.4%, 95% CI = 6.0-11.8). In the logistic model for men, smoking was associated with younger age (p = .005) and being poor (p = .024). In women, spending more than half their lives in the city (p < .001), being poor (p = .002), and coping poorly with stress (defined by lower SOC; OR = 1.04, 95% CI = 1.01-1.08; p = .035) were associated with smoking. Increasing number of adverse events, which replaced SOC in the same models, was significant for women (OR = 1.10, 95% CI = 1.01-1.21; p = .047) but not for men. Education level, employment status, and housing quality were not relevant for men or women. CONCLUSIONS: The high smoking prevalence in men and unchanged rate in women require additional interventions to curtail this behavior.

Comparative assessment of absolute cardiovascular disease risk characterization from non-laboratory-based risk assessment in South African populations.

BACKGROUND: All rigorous primary cardiovascular disease (CVD) prevention guidelines recommend absolute CVD risk scores to identify high- and low-risk patients, but laboratory testing can be impractical in low- and middle-income countries. The purpose of this study was to compare the ranking performance of a simple, non-laboratory-based risk score to laboratory-based scores in various South African populations. METHODS: We calculated and compared 10-year CVD (or coronary heart disease (CHD)) risk for 14,772 adults from thirteen cross-sectional South African populations (data collected from 1987 to 2009). Risk characterization performance for the non-laboratory-based score was assessed by comparing rankings of risk with six laboratory-based scores (three versions of Framingham risk, SCORE for high- and low-risk countries, and CUORE) using Spearman rank correlation and percent of population equivalently characterized as 'high' or 'low' risk. Total 10-year non-laboratory-based risk of CVD death was also calculated for a representative cross-section from the 1998 South African Demographic Health Survey (DHS, n = 9,379) to estimate the national burden of CVD mortality risk. RESULTS: Spearman correlation coefficients for the non-laboratory-based score with the laboratory-based scores ranged from 0.88 to 0.986. Using conventional thresholds for CVD risk (10% to 20% 10-year CVD risk), 90% to 92% of men and 94% to 97% of women were equivalently characterized as 'high' or 'low' risk using the non-laboratory-based and Framingham (2008) CVD risk score. These results were robust across the six risk scores evaluated and the thirteen cross-sectional datasets, with few exceptions (lower agreement between the non-laboratory-based and Framingham (1991) CHD risk scores). Approximately 18% of adults in the DHS population were characterized as 'high CVD risk' (10-year CVD death risk >20%) using the non-laboratory-based score. CONCLUSIONS: We found a high level of correlation between a simple, non-laboratory-based CVD risk score and commonly-used laboratory-based risk scores. The burden of CVD mortality risk was high for men and women in South Africa. The policy and clinical implications are that fast, low-cost screening tools can lead to similar risk assessment results compared to time- and resource-intensive approaches. Until setting-specific cohort studies can derive and validate country-specific risk scores, non-laboratory-based CVD risk assessment could be an effective and efficient primary CVD screening approach in South Africa.

Effectiveness of a group diabetes education programme in underserved communities in South Africa: pragmatic cluster randomized control trial.

BACKGROUND: Diabetes is an important contributor to the burden of disease in South Africa and prevalence rates as high as 33% have been recorded in Cape Town. Previous studies show that quality of care and health outcomes are poor. The development of an effective education programme should impact on self-care, lifestyle change and adherence to medication; and lead to better control of diabetes, fewer complications and better quality of life. TRIAL DESIGN: Pragmatic cluster randomized controlled trialParticipants: Type 2 diabetic patients attending 45 public sector community health centres in Cape TownInterventions: The intervention group will receive 4 sessions of group diabetes education delivered by a health promotion officer in a guiding style. The control group will receive usual care which consists of ad hoc advice during consultations and occasional educational talks in the waiting room. OBJECTIVE: To evaluate the effectiveness of the group diabetes education programmeOutcomes: PRIMARY OUTCOMES: diabetes self-care activities, 5% weight loss, 1% reduction in HbA1c. SECONDARY OUTCOMES: self-efficacy, locus of control, mean blood pressure, mean weight loss, mean waist circumference, mean HbA1c, mean total cholesterol, quality of lifeRandomisation: Computer generated random numbersBlinding: Patients, health promoters and research assistants could not be blinded to the health centre's allocationNumbers randomized: Seventeen health centres (34 in total) will be randomly assigned to either control or intervention groups. A sample size of 1360 patients in 34 clusters of 40 patients will give a power of 80% to detect the primary outcomes with 5% precision. Altogether 720 patients were recruited in the intervention arm and 850 in the control arm giving a total of 1570. DISCUSSION: The study will inform policy makers and managers of the district health system, particularly in low to middle income countries, if this programme can be implemented more widely. TRIAL REGISTER: Pan African Clinical Trial Registry PACTR201205000380384.

The effectiveness of adapted, best practice guidelines for smoking cessation counseling with disadvantaged, pregnant smokers attending public sector antenatal clinics in Cape Town, South Africa.

AIM AND OBJECTIVES: To evaluate the effect of a smoking cessation intervention, based on best practice guidelines on the quit rates of disadvantaged, pregnant women in Cape Town, South Africa. DESIGN: Quasi-experimental using a natural history cohort as a control group, consisting of women attending antenatal care in 2006 and an intervention cohort, attending the same clinics a year later. SETTING: Four, public sector antenatal clinics in Cape Town staffed and managed by midwives. POPULATION: Pregnant women of low socio-economic status. METHODS: The natural history cohort received usual care, whilst the intervention cohort was offered self-help quit materials in the context of brief counseling by midwives and peer counselors. Smoking behavior was measured in early, mid and late pregnancy. The equivalence of the groups in terms of smoking profile, self-reported smoking and demographic variables was assessed at baseline. MAIN OUTCOME MEASURES: Quit rates measured by urinary cotinine towards the end of pregnancy (36-39 weeks gestation). RESULTS: The two cohorts were comparable at baseline. The difference in quit rates between the two cohorts in late pregnancy was 5.3% (95% CI: 3.2-7.4%, p < 0.0001) in an intention to treat analysis. There was also a significant difference in reduction of smoking of 11.8% (95% CI: 5.0-18.4%, p = 0.0006). CONCLUSION: A smoking cessation intervention based on best practice guidelines was effective among high risk, pregnant smokers in South Africa.

A high burden of adverse life events and poor coping mechanisms experienced by urban-dwelling black South Africans.

AIM: In view of the current context of poverty and socio-economic inequalities and the high and rising burdens of HIV infection and non-communicable diseases in South Africa, this study aims to describe the distribution of adverse life events (ALEs) by age and gender, and examine the socio-demographic characteristics, psychosocial coping mechanisms, risky lifestyle behaviours and family burden of HIV-related ill-health associated with ALEs in 25-74-year-old black residents of Cape Town. MATERIALS AND METHODS: In a random cross-sectional sample, 12 ALEs, tobacco and alcohol use, sense of coherence (SOC), locus of control (LOC) and impact of HIV in the family were determined by administered questionnaires. Data analyses included descriptive statistics adjusted for the realised sample. Multivariable linear regression models assessed the independent associations of increasing number of ALEs. RESULTS: Among 1099 participants, mean lifetime score of ALE categories examined was 6.1 ±2.1 (range 0-12) with men reporting significantly higher number of events compared with women (p<0.001). The most frequent ALE was the death of a loved one (88.5%) followed by a major financial crisis (81.2%) with no trend across gender or age group. In the multivariable linear regression model, increasing ALEs were significantly associated with male gender, unemployment, having spent >50% of life in urban areas, >7 years of education, problematic alcohol use and poorer psychosocial coping mechanisms defined by low SOC and LOC. All four variables pertaining to HIV-related burden of ill-health in the family were significantly associated with increasing ALEs. CONCLUSIONS: Considering that lower SOC and LOC and problem drinking were significantly linked to ALEs, policymakers need to formulate strategies that improve coping mechanisms and promote problem-solving behaviours, target the high burden of alcohol misuse and address unemployment.

Lipids, lipoproteins, and apolipoproteins as risk markers of myocardial infarction in 52 countries (the INTERHEART study): a case-control study.

BACKGROUND: Whether lipoproteins are better markers than lipids and lipoproteins for coronary heart disease is widely debated. Our aim was to compare the apolipoproteins and cholesterol as indices for risk of acute myocardial infarction. METHODS: We did a large, standardised case-control study of acute myocardial infarction in 12,461 cases and 14,637 age-matched (plus or minus 5 years) and sex-matched controls in 52 countries. Non-fasting blood samples were available from 9345 cases and 12,120 controls. Concentrations of plasma lipids, lipoproteins, and apolipoproteins were measured, and cholesterol and apolipoprotein ratios were calculated. Odds ratios (OR) and 95% CI, and population-attributable risks (PARs) were calculated for each measure overall and for each ethnic group by comparison of the top four quintiles with the lowest quintile. FINDINGS: The apolipoprotein B100 (ApoB)/apolipoprotein A1 (ApoA1) ratio had the highest PAR (54%) and the highest OR with each 1 SD difference (1.59, 95% CI 1.53-1.64). The PAR for ratio of LDL cholesterol/HDL cholesterol was 37%. PAR for total cholesterol/HDL cholesterol was 32%, which was substantially lower than that of the ApoB/ApoA1 ratio (p<0.0001). These results were consistent in all ethnic groups, men and women, and for all ages. INTERPRETATION: The non-fasting ApoB/ApoA1 ratio was superior to any of the cholesterol ratios for estimation of the risk of acute myocardial infarction in all ethnic groups, in both sexes, and at all ages, and it should be introduced into worldwide clinical practice.

Determinants of target organ damage in black hypertensive patients attending primary health care services in Cape Town: the Hi-Hi study.

BACKGROUND: In South Africa (SA) cardiovascular disease (CVD) is the second leading cause of death, with hypertension (HTN) being the predominant contributor to morbidity and mortality associated with this disease. We examined the prevalence and determinants of target organ damage (TOD) among urban black hypertensive South Africans attending primary health-care (PHC) services in Cape Town. METHODS: Patients on HTN treatment, 35-65 years of age, participated in this cross-sectional study. Data relating to sociodemographic factors, medical history, lifestyle patterns, and HTN care regimens were obtained. Blood and urine samples were analyzed and electrocardiographs (ECGs) were recorded. Sokolow-Lyon and Minnesota Code (MC) criteria were used for identifying left ventricular hypertrophy (LVH). Reduced creatinine clearance (Cockroft-Gault), microalbuminuria, proteinuria, and elevated serum creatinine levels were used for identifying "renal impairment by any criteria" (RIC). Ischemic ECG patterns were classified in terms of MC criteria. Multivariate logistic regression analyses were carried out to identify variables independently associated with TOD. RESULTS: The study sample comprised 403 participants. RIC was identified in 26%, LVH in 35%, and ischemic ECG patterns in 49% of the participants. Uncontrolled HTN and an absence of diabetes were associated with LVH as per Sokolow-Lyon criteria. Older age, the presence of diabetes, and the use of beta-blockers were associated with RIC. Ischemic ECG patterns were associated with uncontrolled HTN, older age, male gender, the consumption of less alcohol, and higher levels of low-density lipoprotein cholesterol (LDL-C). CONCLUSIONS: TOD is common in this group of black hypertensive patients attending PHC sites. Uncontrolled HTN and older age were most often associated with TOD. Reducing the burden of TOD will require improving the quality of HTN care in PHC settings.

Cardiovascular risk and comorbid conditions among Black South Africans with hypertension in public and private primary care settings: the HiHi study.

OBJECTIVE: To describe the HiHi Study and assess cardiovascular disease (CVD) risk profile and comorbid conditions of Black patients receiving hypertension (HTN) care. DESIGN: Cross sectional, descriptive. SETTING: Public and private primary care sites in three townships near Cape Town, South Africa. PARTICIPANTS: 403 hypertensive Black patients (183 men, 220 women), ages 35-65 years. METHODS: Self-reported sociodemographic, lifestyle, and medical history factors were assessed. Height, weight, and blood pressure (BP) were measured and 12-lead electrocardiogram recorded. Blood and urine were collected to assess lipid profile, diabetes, and renal impairment. Type and number of medications were abstracted from medical records. RESULTS: Antihypertensive medication was prescribed for all participants, with HTN controlled (BP<140/90 mm Hg) for 36% of public and 51% of private patients. Mean systolic and diastolic BP were higher in the public than private sector (148/90 +/- 28/13 and 138/ 86 +/- 21/13 mm Hg) as was LVH (37% and 30%) but diabetes (18% and 29%) and obesity (55% and 75%) were less common in the public sector. There were no significant differences between public and private settings in use of antihypertensive medications, total cholesterol > or =5 mmol/L, daily tobacco use, or total CVD risk. More men than women smoked tobacco daily (30% and 6%) and used alcohol excessively (53% and 15%). CONCLUSIONS: Despite attending HTN primary care, CVD risk factors were addressed inadequately. Differences in risk factor prevalence and control were identified by healthcare sector and sex. A critical need exists to improve HTN care and CVD risk management programs for this high risk group.

Determinants of hypertension care and control among peri-urban Black South Africans: the HiHi study.

OBJECTIVE: To examine determinants of hypertension (HTN) care and control among peri-urban hypertensive Black South Africans. DESIGN: Cross-sectional, descriptive. SETTING: Public and private primary care sites in three townships near Cape Town, South Africa. PARTICIPANTS: 403 hypertensive Black patients (183 men, 220 women), ages 35-65 years. METHODS: The Precede-Proceed Model guided the study. Self-report sociodemographics, medical history, health behaviors, health service utilization, quality of life, social support, and exposure to life threats and illness were assessed. Blood pressure (BP) was measured and height and weight recorded. RESULTS: Mean BP (mm Hg) was 151/99 for men, 142/88 for women with BP controlled (<140/90 mm Hg) among 33% of men, 44% of women. Patient-related barriers to HTN care included limited HTN-related knowledge, poor quality of life and stressors such as family death. An unhealthy lifestyle involving smoking cigarettes, physical inactivity and using alcohol excessively was common. In regression models of select socioeconomic, lifestyle risk and HTN care variables, significant predictors of lower SBP and DBP or BP control included: fewer antihypertensive medications, better compliance to HTN recommendations, younger age, female, higher education level, not using alcohol excessively, and private sector healthcare. CONCLUSION: This study identified a high level of barriers to HTN control and the need for comprehensive multilevel interventions to improve HTN care and control in this high-risk population. Furthermore, the data illustrate that the Hill-Bone compliance scale can be a practical tool in primary healthcare settings to identify patient-related factors and guide counseling to improve adherence in HTN care.

Evaluation of a Mass-Media Campaign to Increase the Awareness of the Need to Reduce Discretionary Salt Use in the South African Population.

The South African strategic plan to reduce cardiovascular disease (CVD) includes reducing population salt intake to less than 5 g/day. A mass media campaign was undertaken to increase public awareness of the association between high salt intake, blood pressure and CVD, and focused on the reduction of discretionary salt intake. Community based surveys, before and after the campaign, were conducted in a cohort of black women aged 18-55 years. Questions on knowledge, attitudes and beliefs regarding salt use were asked. Current interest in engaging with salt reduction behaviors was assessed using the "stage of change" model. Five hundred fifty women participated in the baseline study and 477 in the follow-up survey. Most of the indicators of knowledge, attitudes and behavior change show a significant move towards considering and initiating reduced salt consumption. Post intervention, significantly more participants reported that they were taking steps to control salt intake (38% increased to 59.5%, p < 0.0001). In particular, adding salt while cooking and at the table occurred significantly less frequently. The findings suggest that mass media campaigns may be an effective tool to use as part of a strategy to reduce discretionary consumption of salt among the population along with other methods.

Risk factors associated with myocardial infarction in Africa: the INTERHEART Africa study.

BACKGROUND: Cardiovascular disease (CVD) is rising in low-income countries. However, the impact of modifiable CVD risk factors on myocardial infarction (MI) has not been studied in sub-Saharan Africa (SSA). Therefore, we conducted a case-control study among patients with acute MI (AMI) in SSA to explore its association with known CVD risk factors. METHODS AND RESULTS: First-time AMI patients (n=578) were matched to 785 controls by age and sex in 9 SSA countries, with South Africa contributing approximately 80% of the participants. The relationships between risk factors and AMI were investigated in the African population and in 3 ethnic subgroups (black, colored, and European/other Africans) and compared with those found in the overall INTERHEART study. Relationships between common CVD risk factors and AMI were found to be similar to those in the overall INTERHEART study. Modeling of 5 risk factors (smoking history, diabetes history, hypertension history, abdominal obesity, and ratio of apolipoprotein B to apolipoprotein A-1) provided a population attributable risk of 89.2% for AMI. The risk for AMI increased with higher income and education in the black African group in contrast to findings in the other African groups. A history of hypertension revealed higher MI risk in the black African group than in the overall INTERHEART group. CONCLUSIONS: Known CVD risk factors account for approximately 90% of MI observed in African populations, which is consistent with the overall INTERHEART study. Contrasting gradients found in socioeconomic class, risk factor patterns, and AMI risk in the ethnic groups suggest that they are at different stages of the epidemiological transition.

Cost-effectiveness analysis of hypertension guidelines in South Africa: absolute risk versus blood pressure level.

BACKGROUND: Hypertension is responsible for more deaths worldwide than any other cardiovascular risk factor. Guidelines based on blood pressure level for initiation of treatment of hypertension may be too costly compared with an approach based on absolute cardiovascular disease (CVD) risk, especially in developing countries. METHODS AND RESULTS: Using a Markov CVD model, we compared 6 strategies for initiation of drug treatment--2 different blood pressure levels (160/95 and 140/90 mm Hg) and 4 different levels of absolute CVD risk over 10 years (40%, 30%, 20%, and 15%)--with one of no treatment. We modeled a hypothetical cohort of all adults without CVD in South Africa, a multiethnic developing country, over 10 years. The incremental cost-effectiveness ratios for treating those with 10-year absolute risk for CVD >40%, 30%, 20%, and 15% were 700 dollars, 1600 dollars, 4900 dollars, and 11,000 dollars per quality-adjusted life-year gained, respectively. Strategies based on a target blood pressure level were both more expensive and less effective than treatment decisions based on the strategy that used absolute CVD risk of >15%. Sensitivity analysis of cost of treatments, prevalence estimates of risk factors, and benefits expected from treatment did not change the ranking of the strategies. CONCLUSIONS: In South Africa, current guidelines based on blood pressure levels are both more expensive and less effective than guidelines based on absolute risk of cardiovascular disease. The use of quantitative risk-based guidelines for treatment of hypertension could free up major resources for other pressing needs, especially in developing countries.

Coronary heart disease and risk factors in Black South Africans: a case-control study.

BACKGROUND: Coronary heart disease (CHD) was uncommon in Black people living in Africa before 1970. Since then CHD risk factor levels have increased, while CHD rates have remained low. OBJECTIVE: This case-control study aims to assess the relationship between CHD and known risk factors in urban Black South Africans. METHODS: Eighty-nine cases with CHD and 356 controls attending the Kalafong hospital were recruited between 1982 and 1986 and followed up until 1994. Family and personal medical histories were recorded, along with a clinical examination and special investigations to assess risk factor profiles, clinical presentation and target organ damage. The relationship of the risk factors, target organ damage, and the development of CHD was assessed by using a stepwise multiple logistic regression procedure. RESULTS: Far more cases than controls had a family and personal medical history and risk factors related to CHD. Those relating to the development of CHD were family history of myocardial infarction (odds ratio [OR] 17.29; 95% confidence interval [CI] 5.48-54.51), hypertension (OR 8.38, 95% CI 3.66-19.17), family history of hypertension (OR 4.33, 95% CI 2.21-8.52), low high-density lipoprotein cholesterol/low-density lipoprotein cholesterol ratio (OR 2.82, 95% CI 1.24-7.22), and type 2 diabetes (OR 2.99, 95% CI 1.19-6.68). Hypercholesterolemia was marginally associated (OR 2.53, 95% CI .92-6.89). CONCLUSIONS: Evidence is provided that an association exists between CHD and the major risk factors for cardiovascular diseases in urban Black South Africans. A relationship between genetic factors and the development of CHD was also identified in this population group.