Elevated resting heart rate is associated with several cardiovascular disease risk factors in urban-dwelling black South Africans.

This study determined the associations of resting heart rate (RHR) with cardiovascular disease risk factors (CVDRF) in 25-74-year-old black South Africans. This cross-sectional study determined CVDRF by administered questionnaires, clinical measurements and biochemical analyses, including oral glucose tolerance tests. Multivariable linear regression models determined the associations of rising RHR with CVDRF. The basic model comprised age, gender, urbanisation, problematic alcohol use, daily cigarette smoking, physical activity and waist circumference. Glucose, blood pressure and cholesterol variables were entered separately and individually in the above model. Among the 1054 participants (382 men and 672 women, mean age 42.8 years), mean RHR was 70.6 beats per minute (bpm) and significantly higher in women (73.6 bpm) compared with men (65.3 bpm). RHR peaked in 45-54-year-old men (69.3 bpm) and 25-34-year-old women (75.3 bpm). Prevalence of RHR < 60 bpm and ≥90 bpm was 24.3% and 6.2%. In the regression model, female gender, problematic alcohol use, decreasing physical activity and increasing waist circumference were significantly associated with rising RHR. All glycaemic variables (diabetes, fasting glucose and 2-hour glucose) and diastolic blood pressure were significantly associated with RHR. The use of RHR in daily primary healthcare settings to identify increased risk for CVDRF should perhaps be encouraged.

Socioeconomic and modifiable predictors of blood pressure control for hypertension in primary care attenders in the Western Cape, South Africa.

BACKGROUND: Low socioeconomic status is associated with the risk of hypertension. There are few reports of the effect of socioeconomic and potentially modifiable factors on the control of hypertension in South Africa (SA). OBJECTIVES: To investigate associations between patients' socio-economic status and characteristics of primary healthcare facilities, and control and treatment of blood pressure in hypertensive patients. METHODS: We enrolled hypertensive patients attending 38 public sector primary care clinics in the Western Cape, SA, in 2011, and followed them up 14 months later as part of a randomised controlled trial. Blood pressure was measured and prescriptions for antihypertension medications were recorded at baseline and follow-up. Logistic regression models assessed associations between patients' socioeconomic status, characteristics of primary healthcare facilities, and control and treatment of blood pressure. RESULTS: Blood pressure was uncontrolled in 60% (1 917/3 220) of patients at baseline, which was less likely in patients with a higher level of education (p=0.001) and in English compared with Afrikaans respondents (p=0.033). Treatment was intensified in 48% (892/1 872) of patients with uncontrolled blood pressure at baseline, which was more likely in patients with higher blood pressure at baseline (p<0.001), concurrent diabetes (p=0.013), more education (p=0.020), and those who attended clinics offering off-site drug supply (p=0.009), with a doctor every day (p=0.004), or with more nurses (p<0.001). CONCLUSION: Patient and clinic factors influence blood pressure control and treatment in primary care clinics in SA. Potential modifiable factors include ensuring effective communication of health messages, providing convenient access to medications, and addressing staff shortages in primary care clinics.

Differential obesity indices identify the metabolic syndrome in Black men and women in Cape Town: the CRIBSA study.

AIMS: To determine the obesity indices, specifically waist circumference (WC), that identified ≥2 other metabolic syndrome (MS) components (2009 criteria) in 25- to 74-year-old Africans in Cape Town. METHODS: Data were collected from a cross-sectional sample by administered questionnaires, clinical measurements and biochemical analyses. The obesity cut points were estimated by the Youden Index. Logistic regression analyses determined whether obesity cut points identifying ≥2 MS components occurred at true inflection points. RESULTS: Among the 1099 participants, the calculated cut points and 95% confidence intervals (CI) were: men, WC 83.9 cm (81.6-86.2), waist-to-hip ratio (WHR) 0.89 (0.87-0.90), waist-to-height ratio (WHtR) 0.50 (0.48-0.52) and body mass index (BMI) 24.1 kg/m(2) (22.0-26.1); women, WC 94.0 cm (92.6-95.3), WHR 0.85 (0.83-0.87), WHtR 0.59 (0.57-0.60) and BMI 32.1 kg/m(2) (29.7-34.6). Raised WC was significantly associated with ≥2 MS components in men: WC 84.0-93.9 cm (odds ratio (OR): 3.19, 95% confidence interval (CI): 1.73-5.85) and WC ≥94.0 cm (OR: 8.50, 95% CI: 4.44-16.25) compared with WC <84.0 cm, and in women: WC 80.0-93.9 cm (OR: 2.93, 95% CI: 1.32-6.54) and WC ≥94.0 cm (OR: 5.33, 95% CI: 2.40-11.85) compared with WC <80.0 cm. In the logistic model with BMI for women, obesity (OR: 3.60, 95% CI: 1.82-7.10) but not overweight (P = 0.063) was significantly associated with ≥2 MS components. CONCLUSIONS: Obesity cut points for Africans should be re-evaluated and adjusted accordingly.

South Africa's salt reduction strategy: Are we on track, and what lies ahead?

On 2 September 2016, 25 local and international participants from various sectors met in Cape Town to take stock of South Africa (SA)'s progress in salt reduction and develop a roadmap for action. SA is centre stage on salt reduction globally, being the first country to mandate salt reduction across a wide range of processed foods. Excessive salt intake contributed by processed foods and discretionary sources motivated SA to implement a public awareness campaign in parallel with legislation to reduce salt intake to the World Health Organization target of 5 g per day. Five priority areas were identified for continued action on salt reduction, including obtaining research funds for continued monitoring and compliance of salt reduction targets. Determining the contribution of foods eaten out of home to total salt intake and implementing strategies to address this sector were also highlighted as key actions. Lastly, implementing the next stage of the Salt Watch awareness campaign to change.

The midwife's role in providing smoking cessation interventions for pregnant women: The views of midwives working with high risk, disadvantaged women in public sector antenatal services in South Africa.

OBJECTIVE: The purpose of this study was to assess the knowledge, attitudes, beliefs and current practices of South Africa midwives in relation to providing smoking cessation education or counselling to pregnant women. This was with a view to involving them in a potential smoking cessation intervention, targeting a sub-group of South African women who are at particularly high risk of the adverse pregnancy outcomes associated with smoking. DESIGN: A cross-sectional survey of midwives, supplemented by individual, in depth, qualitative interviews. SETTING: Public sector antenatal clinics serving this particular community of women in five of the major urban centres of South Africa. PARTICIPANTS: A total of 102 midwives were surveyed across 29 antenatal clinics and 24 were interviewed. MEASUREMENTS: Self-administered survey and semi-structured, individual interviews describing constructs from the Theory of Planned Behaviour with respect to the provision of smoking cessation education/counselling, including: knowledge, attitudes, subjective norms and perceived behavioural control. FINDINGS: The majority of midwives accepted that providing smoking cessation advice was a part of their remit, perceived prevailing social norms to be supportive and were, overall, positively predisposed to participating in a smoking cessation intervention in antenatal clinics. However, the study identified a number of constraints to midwives fulfilling this role, which affected their perceived behavioural control. These included stressful working conditions, too little time, a dearth of educational resources and a lack of knowledge of best practice intervention methods and counselling skills. Perceived patient resistance to quitting was a further obstacle. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: For the intervention to be accepted and adopted by midwives, it would need to offer them an opportunity to enhance their professional knowledge and expertise, provide them with attractive educational aids and take into account the very limited time they have for smoking education. Patient-centred, best practice methods for cessation counselling may help midwives overcome the problem of patient resistance and to engage smokers in constructive discussions about smoking with a greater prospect of success.

Differential associations of cardiovascular disease risk factors with relative wealth in urban-dwelling South Africans.

BACKGROUND: To examine the associations of cardiovascular disease risk factors (CVDRF) with wealth, defined by the asset index, in 25- to 74-year-old black Africans in Cape Town. METHODS: Assets, including consumer durable goods, and CVDRF were determined in a randomly selected cross-sectional sample. A principal component analysis of the pooled data, based on assets that defined wealth, was used to develop an asset index. Ordinal logistic regression analyses assessed the independent associations of CVDRF with wealth tertiles. RESULTS: Among the 1099 participants, the least poor compared with the poorest tertile had significantly higher prevalence of diabetes (16.3 versus 9.6%), hypercholesterolaemia (33.9 versus 21.4%), obesity (45.4 versus 26.3%) and fat intake ≥30% of diet (44.2 versus 29.3%). Daily smoking was highest in the poorest (35.8%) versus the least poor (26.4%). Psychosocial stress (low sense of coherence or locus of control) was significantly higher in poorer participants. In the regression analyses, wealth was associated with male gender [odds ratio (OR): 1.89, 95% confidence interval (CI): 1.37-2.60], urbanization (OR: 1.02, 95% CI: 1.01-1.02), high fat intake, obesity and hypercholesterolaemia. Daily smoking, problematic alcohol use (OR: 0.70, 95% CI: 0.52-0.94) and psychosocial stress were inversely related to wealth. CONCLUSIONS: Differential distribution of CVDRF by wealth mandates incorporating equity components when developing tailored interventions.

Using formative research to develop a nutrition education resource aimed at assisting low-income households in South Africa adopt a healthier diet.

As part of a comprehensive programme to prevent non-communicable disease in South Africa, there is a need to develop public education campaigns on healthy eating. Urban populations of lower socioeconomic status are a priority target population. This study involved formative research to guide the development of a nutrition resource appropriate to the budgetary constraints and information needs of poor households in the major urban centres of South Africa. Twenty-two focus groups were convened to explore the target audience's knowledge, beliefs, attitudes and practices as they related to healthy eating and their views about the proposed nutrition resource (N = 167). A brief questionnaire assessed eating and cooking practices among focus group participants. Key informant interviews with eight dieticians/nutritionists working with this population added to the focus group findings. The research identified important issues to take into account in the development of the resource. These included the need to: directly address prevalent misconceptions about healthy eating and unhealthy eating practices; increase self-efficacy regarding the purchasing and preparation of healthy food; represent diverse cultural traditions and consider the issues of affordability and availability of food ingredients. This study demonstrates the value of using formative research in the design of nutrition-related communication in a multicultural, poor, urban South African setting.

Effectiveness of a group diabetes education programme in under-served communities in South Africa: a pragmatic cluster randomized controlled trial.

AIM: To evaluate the effectiveness of group education, led by health promoters using a guiding style, for people with type 2 diabetes in public sector community health centres in Cape Town. METHODS: This was a pragmatic clustered randomized controlled trial with 17 randomly selected intervention and 17 control sites. A total of 860 patients with type 2 diabetes, regardless of therapy used, were recruited from the control sites and 710 were recruited from the intervention sites. The control sites offered usual care, while the intervention sites offered a total of four monthly sessions of group diabetes education led by a health promoter. Participants were measured at baseline and 12 months later. Primary outcomes were diabetes self-care activities, 5% weight loss and a 1% reduction in HbA(1c) levels. Secondary outcomes were self-efficacy, locus of control, mean blood pressure, mean weight loss, mean waist circumference, mean HbA1c and mean total cholesterol levels and quality of life. RESULTS: A total of 422 (59.4%) participants in the intervention group did not attend any education sessions. No significant improvement was found in any of the primary or secondary outcomes, apart from a significant reduction in mean systolic (-4.65 mmHg, 95% CI 9.18 to -0.12; P = 0.04) and diastolic blood pressure (-3.30 mmHg, 95% CI -5.35 to -1.26; P = 0.002). Process evaluation suggested that there were problems with finding suitable space for group education in these under-resourced settings, with patient attendance and with full adoption of a guiding style by the health promoters. CONCLUSION: The reported effectiveness of group diabetes education offered by more highly trained professionals, in well-resourced settings, was not replicated in the present study, although the reduction in participants' mean blood pressure is likely to be of clinical significance.

G-protein-coupled receptor kinase 4 polymorphisms predict blood pressure response to dietary modification in Black patients with mild-to-moderate hypertension.

Dopamine via G-protein-coupled receptor kinase 4 (GRK-4) regulates sodium (Na) balance in the proximal tubule of the kidney. Single-nucleotide polymorphisms of GRK-4 have been linked to impaired natriuresis and salt-sensitive hypertension. The purpose of this report was to determine the effect of GRK-4 gene polymorphisms on the blood pressure (BP) responses to dietary intervention. Black subjects aged 50-75 years with mild-to-moderate hypertension were randomised to an 8-week dietary intervention (n=40) or standard diet (n=40). BP was measured at baseline and at 8 weeks using 24-h ambulatory BP. All subjects underwent DNA analysis for the R65L and A142V polymorphisms. Data were analysed using generalised linear models. For the whole group, between-diet differences in mean 24-h ambulatory systolic BP was -4.53 mm Hg (95% confidence interval -9.05 to -0.01, P=0.05). In the intervention arm, the combined CC and CT group of the A142V showed a significant reduction in both systolic and diastolic ambulatory BP (-10 mm Hg, P=0.023 and -6.5 mm Hg, P=0.01, respectively), whereas the TT group demonstrated no reduction. Similarly, the combined GG and GT groups of the R65L showed a significant reduction in ambulatory BP (-10.6 mm Hg for systolic, P=0.004 and 5.8 mm Hg for diastolic, P=0.006). There was no response in the TT group. GRK-4 polymorphisms predict BP response to dietary modification in Black subjects with mild-to-moderate hypertension. These data may provide at least one among a range of clinical tools to target selected hypertensives to dietary intervention.

Achieving blood pressure goals globally: five core actions for health-care professionals. A worldwide call to action.

The prevalence of hypertension continues to rise across the world, and most patients who receive medical intervention are not adequately treated to goal. A Working Group including representatives of nine international health-care organizations was convened to review the barriers to more effective blood pressure control and propose actions to address them. The group concluded that tackling the global challenge of hypertension will require partnerships among multiple constituencies, including patients, health-care professionals, industry, media, health-care educators, health planners and governments. Additionally, health-care professionals will need to act locally with renewed impetus to improve blood pressure goal rates. The Working Group identified five core actions, which should be rigorously implemented by practitioners and targeted by health systems throughout the world: (1) detect and prevent high blood pressure; (2) assess total cardiovascular risk; (3) form an active partnership with the patient; (4) treat hypertension to goal and (5) create a supportive environment. These actions should be pursued with vigour in accordance with current clinical guidelines, with the details of implementation adapted to the economic and cultural setting.

Wheeze, asthma diagnosis and medication use: a national adult survey in a developing country.

BACKGROUND: As relatively little is known about adult wheeze and asthma in developing countries, this study aimed to determine the predictors of wheeze, asthma diagnosis, and current treatment in a national survey of South African adults. METHODS: A stratified national probability sample of households was drawn and all adults (>14 years) in the selected households were interviewed. Outcomes of interest were recent wheeze, asthma diagnosis, and current use of asthma medication. Predictors of interest were sex, age, household asset index, education, racial group, urban residence, medical insurance, domestic exposure to smoky fuels, occupational exposure, smoking, body mass index, and past tuberculosis. RESULTS: A total of 5671 men and 8155 women were studied. Although recent wheeze was reported by 14.4% of men and 17.6% of women and asthma diagnosis by 3.7% of men and 3.8% of women, women were less likely than men to be on current treatment (OR 0.6; 95% confidence interval (CI) 0.5 to 0.8). A history of tuberculosis was an independent predictor of both recent wheeze (OR 3.4; 95% CI 2.5 to 4.7) and asthma diagnosis (OR 2.2; 95% CI 1.5 to 3.2), as was occupational exposure (wheeze: OR 1.8; 95% CI 1.5 to 2.0; asthma diagnosis: OR 1.9; 95% CI 1.4 to 2.4). Smoking was associated with wheeze but not asthma diagnosis. Obesity showed an association with wheeze only in younger women. Both wheeze and asthma diagnosis were more prevalent in those with less education but had no association with the asset index. Independently, having medical insurance was associated with a higher prevalence of diagnosis. CONCLUSIONS: Some of the findings may be to due to reporting bias and heterogeneity of the categories wheeze and asthma diagnosis, which may overlap with post tuberculous airways obstruction and chronic obstructive pulmonary disease due to smoking and occupational exposures. The results underline the importance of controlling tuberculosis and occupational exposures as well as smoking in reducing chronic respiratory morbidity. Validation of the asthma questionnaire in this setting and research into the pathophysiology of post tuberculous airways obstruction are also needed.

Doctors' attitudes and practices regarding smoking cessation during pregnancy.

OBJECTIVE: To investigate the current smoking cessation practices and attitudes of doctors working in the public antenatal services, as well as their perceived barriers to addressing the issue in the context of routine care. STUDY DESIGN: The study was qualitative, consisting of 14 semistructured, one-to-one interviews with doctors purposefully sampled from 5 public sector hospitals in Cape Town, South Africa. RESULTS: The doctors in this study regarded HIV, poor nutrition, alcohol abuse and psychosocial stress as equal or higher risks to pregnant women than smoking. They tended to underestimate the magnitude of the risk of smoking during pregnancy. Doctors were unaware of the guidelines offering clinicians brief, structured approaches to smoking cessation counselling and were generally pessimistic that they could influence the smoking behaviour of pregnant women, especially poor, disadvantaged women who face multiple barriers to achieving health-enhancing behaviour. However, most doctors were concerned about improving their communication with pregnant women about smoking and open to adopting new approaches or tools that could assist them. Perceived barriers to providing smoking cessation interventions included a lack of counselling skills and educational resources, other pressing priorities, too little time, and the levels of stress currently experienced by doctors and midwives working in public sector hospitals as a result of dramatic staff and budget cuts. CONCLUSION: The study suggests that doctors working in the public sector antenatal services are not routinely addressing the issue of smoking during pregnancy or using effective methods to assist women to give up smoking. Doctors need convincing that smoking cessation interventions can be effective. The promotion and provision of evidence-based guidelines such as the Clinical Practice Guideline for Treating Tobacco Use and Dependence (Fiore, 2000), with minimal training, is a possible strategy for integrating smoking cessation interventions into routine antenatal care in South Africa.

Predictors of chronic bronchitis in South African adults.

SETTING: National household survey of adults in South Africa, a middle income country. OBJECTIVE: To determine the prevalence and predictors of chronic bronchitis. DESIGN: A stratified national probability sample of households was selected. All adults in the selected households were interviewed. Chronic bronchitis was defined as chronic productive cough. Socio-demographic predictors were wealth, education, race, age and urban residence. Personal and exposure variables included history of tuberculosis, domestic exposure to smoky fuels, occupational exposures, smoking and body mass index. RESULTS: The overall prevalence of chronic bronchitis was 2.3% in men and 2.8% in women. The strongest predictor of chronic bronchitis was a history of tuberculosis (men, odds ratio [OR] 4.9; 95% confidence interval [CI] 2.6-9.2; women, OR 6.6; 95%CI 3.7-11.9). Other risk factors were smoking, occupational exposure (in men), domestic exposure to smoky fuel (in women) and (in univariate analysis only) being underweight. Wealth and particularly education were protective. CONCLUSION: The pattern of chronic bronchitis in South Africa suggests a combination of risk factors that includes not only smoking but also tuberculosis, occupational exposures in men and domestic fuel exposure in women. Control of these risk factors requires public health action across a broad front. The protective role of education requires elucidation.

Allelic variation in the promoter region of the LDL receptor gene: analysis of an African-specific variant in the FP2 cis-acting regulatory element.

DNA samples of 2303 individuals from nine different population groups were screened for variant -175g-->t in the promoter region of the low-density lipoprotein receptor (LDLR) gene. The -175g-->t variant detected at carrier frequencies of 3-10% in different African population groups was absent in the Caucasian and Asian (Chinese) individuals studied. In contrast to previous findings in Black South Africans where this polymorphism predominated in patients with familial hypercholesterolaemia (FH), it occurred at a significantly lower frequency in hypercholesterolaemics from the recently admixed Coloured population of South Africa compared with population-matched controls (P<0.0001). Haplotype and mutation analysis excluded the likelihood that this finding is due to association with a specific disease-related mutation in FH patients, although reversal of the positive association with FH observed in the Black population may, at least in part, be due to admixture linkage disequilibrium. Transient transfection studies in HepG2 cells demonstrated that the -175t allele is associated with a non-significant decrease ( approximately 7%) of LDLR transcription in the absence of sterols. The data presented in this study raise the possibility that the -175g-->t polymorphism may have subtle effects that become clinically important within certain genetic and/or environmental contexts.

Poor nutritional status in older black South Africans.

A cross-sectional analytical study was undertaken to describe the nutritional status and dietary intake of the elderly black population of Cape Town. A stratified proportional sample of 148 men and women aged 60 years and older (mean = 68.9+/-5.7) was selected from informal and formal peri-urban settlements. The study population was predominantly urbanized, although most subjects had migrated from non-urban areas. Trained fieldworkers conducted a 24-h recall dietary assessment and performed anthropometrical measurements. Mean energy intakes fell below the recommended dietary allowance (RDA) for both men and women; 27% and 36% of men and women, respectively, had energy intakes <67% RDA. Total fat intake was low and contributed 24-26% total energy. Mean dietary fibre intake was low at 11-16 g/day. Mean intakes fell below the RDA for vitamin D, calcium, zinc and vitamin B6. Less than two and a half servings per day were consumed from the vegetable and fruit group and less than one serving per day from the calcium-rich food group. Over half (51.3%) of the women and 18% of the male were obese (body mass index > or =30). We concluded that older black subjects in Cape Town have energy profiles in line with prudent dietary guidelines and more favorable than other elderly groups in the country, with regard to atherogenic risk. However, micronutrient and dietary fiber intake is inadequate, largely due to low reported energy intakes, particularly in women.

Hypertension in South African adults: results from the Demographic and Health Survey, 1998.

OBJECTIVES: To determine the prevalence and treatment status of hypertension in South Africa. DESIGN: National cross-sectional survey. SETTING: 13 802 randomly selected South Africans, 15 years and older, were visited in their homes in 1998. METHODS: Trained fieldworkers completed questionnaires on lifestyle and chronic diseases, measured blood pressure with an Omron manometer and recorded chronic drug utilization. Drugs were classified using the Anatomical Therapeutic Chemical index. RESULTS: The mean systolic blood pressure for men and women was 123 mmHg (SE 0.37) and 119 mmHg (SE 0.36), while the mean diastolic level was 76 mmHg (SE 0.25) and 75 mmHg (SE 0.20), respectively. When using a cut-off point of 140/90 mmHg the hypertension prevalence rate (age-adjusted to the South African Population, Census 1996) was 21% for both genders. Using the current cut-off point (160/95 mmHg) for South Africa, the prevalence rate was 11% for men and 14% for women. For men with hypertension, the level of awareness, taking antihypertensive medication and having controlled blood pressure (< 160/95 mmHg) were 41, 39 and 26% respectively, while for women these rates were 67, 55 and 38% respectively. CONCLUSIONS: This survey revealed high levels of hypertension in the South African community with inadequate treatment status.

The epidemic of obesity in South Africa: a study in a disadvantaged community.

OBJECTIVE: The objective of this study was: 1) to determine the anthropometric profile of adults in Mamre, a small town in South Africa, which has a population of mixed ancestry ("colored" people of Afro-Euro-Malay-Khoisan ancestry); and 2) to determine the change in this profile between 1989 and 1996. DESIGN: Cross-sectional surveys conducted in random samples of adults in 1989 and 1996. PARTICIPANTS: The subjects were 684 women and 529 men in 1989, and 546 women and 430 men in 1996, aged 15 and older. MAIN OUTCOME MEASURES: The following measurements were recorded: height, weight, and circumference of waist, hips, and mid-upper arm. RESULTS: Based on data from the 1996 survey, 32% of women are obese (body mass index [BMI] > or = 30) at ages 25-44 years, rising to 49% at ages 45-64 years. A much lower prevalence of obesity is seen in men: 14% at ages 35-64 years. Obesity levels significantly increased in women between the two surveys (P=.015): up from 44% in 1989 to 49% in 1996 at ages 45-64 years. There was an increase in the prevalence of overweight (BMI 25-29.9) in men, though not in obesity. Mean BMI increased by about 3% in women and 2% in men between 1989 and 1996. CONCLUSIONS: This study conducted among people of mixed ancestry living in a disadvantaged community in South Africa shows that half of middle-aged women are obese. A rising trend in BMI was seen in adults of both sexes between 1989 and 1996. This trend may be explained by factors associated with rural-urban transition, including electrification, reduced physical activity, and increasing availability of energy-dense food.