Biomedical subjects

A S Swanepoel

Publications and source records attributed to A S Swanepoel.

17 recordsLinked to original sources

PubMed1997

Twelve-year results of the Coronary Risk Factor Study (CORIS).

BACKGROUND: After 4 years a coronary heart disease risk factor intervention programme produced equally large and significantly reduced risk profiles in two intervention towns compared with a control town. Intervention effects through community participation were assessed after cessation of the active intervention programme. The impact of secular trends was assessed in the control town and in two previously unstudied towns. METHODS: Cross-sectional surveys were done in a random sample of 1620 participants aged 15-64 years in the three original towns 12 years after the initial quasi-experimental study. Two years later 327 subjects, aged 35-44 years, were studied in the original control town and in two non-intervention towns. Risk factor knowledge, smoking and medical histories were determined by questionnaire. Blood pressure, anthropometry and blood lipids were recorded. Data were compared across towns, and with previous surveys. RESULTS: At 12 years the low intensity intervention town maintained a significantly better risk factor profile than the control town, while the high intensity intervention town now matched the control town. No differences in risk factor profiles were found between the control town and the two new towns. Deaths from coronary heart disease and strokes showed a downward trend in the study area. CONCLUSIONS: Outcome suggests large ongoing secular trends during the study could have overtaken the intervention effects in the high intensity town, but not in the low intensity intervention town, which showed an advantage over the control town. These results support the effectiveness of media-based, long term health promotion strategies to reduce cardiovascular disease risk profiles.

Adolescent↗

PubMed1996

Estimation of the prevalence of familial hypercholesterolaemia in a rural Afrikaner community by direct screening for three Afrikaner founder low density lipoprotein receptor gene mutations.

We have determined the prevalence of familial hypercholesterolaemia (FH) in a rural Afrikaner community by means of direct DNA screening for three founder-related Afrikaner low density lipoprotein (LDL) receptor gene mutations. A random sample of 1612 persons, aged 15-64 years, was selected as a subsample of 4583 subjects from an Afrikaner community living in the south-western Cape, South Africa. Participants who had a total serum cholesterol (TC) in the high TC category as defined in the consensus recommendations by the Southern African Heart Foundation, were screened for three founder-related LDL receptor gene mutations, causing FH in 90% of Afrikaners. Of the subsample, 201 participants (12.5%) had TC levels above the 80th percentile. In this group the combined prevalence of the three common Afrikaner LDL receptor gene defects (D206E, FH Afrikaner-1; V408M, FH Afrikaner-2; D154N, FH Afrikaner-3) was calculated as 1: 83. When taking into account the reported background prevalence of other FH gene defects of 1:500 in this community, their overall prevalence of FH was estimated to be 1:72. The significant differences found between the FH patients and other high risk patients with raised cholesterol levels were higher TC and LDL cholesterol levels and lower high density lipoprotein cholesterol levels in FH patients. The treatment status of the molecularly identified FH patients and other hypercholesterolaemic persons suggests that this condition is inadequately diagnosed and poorly managed in this study population. An extrapolation to the entire South African population suggests that there are about 112000 FH patients in the country who are under-diagnosed as a group and therefore not receiving the care that would help to reduce the burden of FH-associated ischaemic heart disease in South Africa.

Adolescent↗

PubMed1993

Community-based intervention: the Coronary Risk Factor Study (CORIS).

The Coronary Risk Factor Study (CORIS) examined the feasibility and effectiveness of a multifactorial community intervention programme to reduce coronary heart disease (CHD) risk factor levels. Three Afrikaner communities were surveyed before and after a 4-year intervention in two of the communities, the third serving as a control (C). Intervention was primarily by small mass media (low-intensity intervention, LII) or by small mass media plus interpersonal intervention to high-risk individuals (high-intensity intervention, HII). After allowing for change in C, significant net reductions in blood pressure, smoking, and risk score were obtained in LII and HII alike. Though the total cholesterol (TC) fell by 10-12%, there was no net reduction in favour of the intervention communities. However, LII and HII resulted in significant increases in high-density lipoprotein cholesterol (HDL-C) levels and HDL-C/TC ratios in comparison to C. Overall, the LII community fared almost as well as the HII community, and high-risk individuals did not show a greater change in risk factors than others. We conclude that community-based intervention works, and that in these particular communities a media-based health education programme was more cost-effective than one which adds a greater degree of interpersonal intervention.

Adolescent↗

PubMed1993

The intervention effects of a community-based hypertension control programme in two rural South African towns: the CORIS Study.

The objective of the hypertension programme of the Coronary Risk Factor Study (CORIS) was to evaluate the effectiveness of the first 4 years of community-based intervention. The hypertension intervention model comprised a blood pressure station where the whole population was screened for hypertension, non-drug management was provided and hypertensives were monitored after referral to general practitioners for drug therapy. Two levels of intervention were maintained: in the high-intensity intervention town (N = 2,278) hypertensives were actively followed up, and in the low-intensity intervention town (N = 2,620) no active follow-up procedure existed. A third town acted as control (N = 2,290). In the cohort which was hypertensive at baseline, the net decreases in systolic blood pressure (mean +/- SE) after correction for changes in the control town were 0.5 +/- 2.2 mmHg (men) and 4.5 +/- 2.2 mmHg (women) in the low-intensity intervention town, and 5.6 +/- 2.3 mmHg (men) and 7.5 +/- 2.2 mmHg (women) in the high-intensity intervention town. The net decrease in diastolic blood pressure was 3.4 +/- 1.2 mmHg (men) and 4.4 +/- 1.1 mmHg (women) in the low-intensity intervention town, and 6.1 +/- 1.2 mmHg (men) and 5.9 +/- 1.1 mmHg (women) in the high-intensity intervention town. These reductions were statistically significant with one exception. The changes in the total population in the 3 communities after 4 years of intervention were similar to those found in the hypertensive cohort.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1991

Changes in smoking during a community-based cardiovascular disease intervention programme. The Coronary Risk Factor Study.

A prospective anti-smoking clinical trial was conducted as part of a coronary risk factor intervention study in three rural South African communities in the south-western Cape over a period of 4 years. The aim of this part of the study was to reduce smoking rates in two of the communities through application of high- and low-intensity intervention. The effect was evaluated by examining the net change in smoking habits, which was defined as the residual change in the intervention areas after allowing for change in the reference area. This paper presents the analyses of the estimated effect of the programme on the cohort aged 15-64 years at baseline who participated in the two surveys (4,087 subjects). The intervention programme among men in the high-intensity intervention area resulted in a reduction of 8.4% in smoking rates and 13.0% in the amount smoked per day. Among women in this area there was a reduction of 30.6% in smoking rates and 20.5% in amount smoked. Smoking and the amount smoked per day also decreased in the low-intensity intervention area, but less so than in the high-intensity intervention area. Smoking quit rates were strongly associated with initial smoking levels, with light smokers being significantly more successful quitters than heavy smokers. This study has proved that a community-based intervention programme can effectively reduce smoking.

Adolescent↗

PubMed1991

Change in knowledge in a coronary heart disease risk factor intervention study in three communities.

We investigated health and diet knowledge as it relates to coronary heart disease (CHD) in three rural areas which participated in a community-oriented CHD risk factor intervention study. Knowledge of risk factors (risk knowledge) was fairly satisfactory at baseline, but diet knowledge was poor. Males, the young, and individuals with a lower level of education had less knowledge. Intervention consisted of a 3-year small mass media programme in one community (low-intensity intervention, LII), additional interpersonal intervention to high-risk individuals in the second (high-intensity intervention, HII), and no intervention in the control community (C). In the cohorts, with the baseline survey and the follow-up study 4 years apart, knowledge improved by 8.1% points in males (7.5% in females) in the HII community and by 7.1% (6.5%) in the LII community, compared to 5.5% (4.8%) in the C community (P less than 0.01). Diet knowledge improved more than risk knowledge, and individuals with lower initial scores benefitted most. Female scored highest. Educational level made a modest positive contribution to knowledge gain, after adjusting for differences in baseline knowledge. High-risk individuals did not have better knowledge at baseline, nor did they gain more from the intervention. We conclude that community intervention over a 4 year period, based on community diagnosis and tailored to the community's needs, can improve health knowledge.

Adolescent↗

PubMed1991

Effect of breast feeding on the plasma cholesterol and growth of infants.

The effect of breast-feeding on plasma cholesterol, body weight, and body length was studied longitudinally in a large free-living cohort of infants (n = 512) from birth until the age of 1 year. Of the cohort, 21.4% were exclusively breast-fed for at least 3 months, 39.3% received bottle-feeding, and 39.3% received a combination of breast- and bottle-feeding. At birth the plasma cholesterol was similar in the three groups. After 3 months the mean plasma cholesterol and proportion of hypercholesterolemic infants in the breast-fed group were significantly (p less than 0.001) higher than that of the other two groups. These differences had disappeared at the age of 1 year. Breast-fed infants weighed less at 3 and 12 months, but body length was similar to those of the other groups. These results suggest that breast-feeding elevates plasma cholesterol by a direct mechanism and that the effect persists only as long as the breast-feeding is continued.

Analysis of Variance↗

PubMed1990

Choice of coronary heart disease risk factor variables in a cross-sectional study of white South Africans.

This report explores the possibility of redefining risk factors so as to improve their observed associations with prevalent coronary heart disease (CHD). A large cross-sectional community study of 5,895 white males and females aged 25-64 years yielded 240 cases of confirmed angina pectoris and 361 of confirmed myocardial infarction. Odds ratios for CHD end-points by level of risk factors when risk factors were expressed in the conventional manner (e.g. total cholesterol, systolic and diastolic blood pressure or current smoking) were often low and not statistically significant. Redefinition of risk factor variables in a manner that improved their specificity or compensated to some extent for the decreased risk factor exposure as a result of a CHD event (e.g. stopping smoking after a myocardial infarct) improved the strength of association. In this study, the most useful cholesterol variable was total cholesterol minus high-density lipoprotein cholesterol; for blood pressure the most useful variable was a blood pressure of 160/95 mmHg or above and/or being on anti-hypertensive treatment; and for smoking the most useful variable was the total duration of smoking (previous and current). Strong associations with CHD end-points were also found for conventionally expressed serum uric acid, diabetes prevalence (females) and family history of CHD. The study suggests that appropriate redefinition of risk factor variables and CHD end-points in cross-sectional studies yields associations similar in strength and direction to those found in prospective studies.

Adult↗

PubMed1990

The snacking habits of white preschool children.

Three-day estimated dietary records were kept for 194 white 3- and 4-year-old children to determine and evaluate the extent, nature and quality of their snacking. All but 1 child ate between meals, with morning and afternoon snacking being favoured in terms of frequency and quantity. Soft drinks were consumed most frequently, followed by fresh fruits and fruit juices, sweets and chocolates, milk and sugar. Between-meal eating contributed more than one-third of the average day's energy and approximately one-quarter of most vitamins and minerals to the children's diets. Foods eaten between meals were, however, significantly less nutrient-dense than mealtime foods. Non-basic foods supplied more energy to the diet than any of the five basic food groups, but minimal quantities of micronutrients. Sugar consumption, mostly in the form of sugary foods and drinks, was high, but was not consumed exclusively between meals. Such children should be encouraged to make more use of basic commodities, particularly when snacking.

Child, Preschool↗

PubMed1990

Socio-economic status, risk factors and coronary heart disease. The CORIS baseline study.

The relationship of socio-economic status (SES) indicators and coronary risk factors (RFs) with coronary heart disease (CHD) prevalence was examined in 5 620 subjects aged 20-60 years who participated in the Coronary Risk Factor (CORIS) baseline study. Education and income (with some exceptions in males) were strongly and inversely related to hypercholesterolaemia, low high-density lipoprotein cholesterol, hypertension, smoking, overweight and prevalence of angina pectoris. In contrast, type A behaviour was positively associated with higher income and education. Females showed stronger SES-RF relationships than males. Town-dwelling females were more likely to be smokers, and had a higher prevalence of angina pectoris and myocardial infarction. The lowest overall prevalence of RFs, angina pectoris and myocardial infarction was found in the professional and managerial categories for both males and females. The SES indicators had little or no independent effect on CHD prevalence in multivariate logistic analyses after inclusion of the standard RFs. We conclude that these indicators relate to RFs, and through them to CHD.

Adult↗

PubMed1990

Hypercholesterolaemia in a rural white population and its relationship with other coronary risk factors.

The risk factor and dietary associations of hypercholesterolaemia were analysed. Twenty per cent of the 6,332 respondents aged 20-64 years in the Coronary Risk Factor Study (CORIS) were considered hypercholesterolaemic (i.e. above the 80th percentile). In this sample only 13.4% of men and 6.7% of women were on treatment, and only 32.7% and 37.1% respectively had 'desirable' high-density lipoprotein cholesterol levels. Hypercholesterolaemia was significantly associated with a personal or family history of coronary heart disease, hypertension, smoking, obesity and hyperuricaemia. Analysis of the dietary intakes of a 15% subsample of the total population revealed no significant differences between high- and low-risk subjects in intake of dietary fats and cholesterol. However, high-risk subjects consumed significantly more animal protein and significantly less dietary fibre than those with a low cholesterol level. These findings reflect a subpopulation at high risk of coronary heart disease. Their risk can be reduced to some extent by population strategies towards healthier lifestyles; ultimately the high-risk individuals have to be identified and appropriately treated.

Adult↗

PubMed1989

The contribution of different food groups to the energy, fat and fibre intake of the Coronary Risk Factor Study (CORIS) population.

A dietary survey done in 1979 on a randomly selected 15% subsample (454 males and 659 females, 15-64 years old) of the 1979 Coronary Risk Factor Study (CORIS) population showed that this population consumed a typical Western diet. In order to identify specific weaknesses in the dietary habits of the population, additional analyses were performed on the data. Foods consumed by the respondents were grouped into 8 groups and the percentage contribution of each of these food groups to total energy intake, total macronutrients, dietary cholesterol and dietary fibre intake was determined. A reference, an 8.4 MJ diet, calculated according to the prudent diet guidelines, was also analysed as described above. The results showed that the CORIS respondents' dietary intake compared unfavourably with the values of the reference diet. The meat group was the main source of total fat, saturated fat and dietary cholesterol. The fat group was the second most important source of total fat in the diet, while the milk group was the second most important source of saturated fat. The study population preferred refined cereals and had a low fruit and vegetable intake. These results revealed specific shortcomings in the dietary habits of the CORIS population and emphasised the need for changes necessary to meet the requirements for a prudent diet.

Adolescent↗

PubMed1989

An evaluation of two guidance programmes to promote breast-feeding.

During the past ten years a comprehensive research project has been undertaken to develop a guidance programme in three adjacent communities in the South-Western Cape with the aim of lowering the high incidence of coronary heart disease. The purpose of this substudy was to determine whether the guidance provided in the different communities had any influence on the knowledge of and attitudes towards the nutrition of pregnant women, babies and infants as well as breast-feeding practices of the women who gave birth during the period 1980 to 1986. In the first community guidance was provided by means of small mass media and interpersonal communication whereas only the small mass media were employed in the second. The third served as the control community. The findings suggest that the combined interpersonal and mass media programme was more successful than the mass media programme alone.

Breast Feeding↗

PubMed1988

Intake of macronutrients and their relationship with total cholesterol and high-density lipoprotein cholesterol. The Coronary Risk Factor Study, 1979.

In a dietary study on a subsample (1,113 males and females, 15-64 years of age) of the Coronary Risk Factor Study (CORIS) population, dietitians used the 24-hour recall method by interview to quantify nutrient intake and energy distribution and to investigate the relationship between dietary variables and blood lipid values. Mean total fat intakes varied from 35% to 37% of daily energy intake for different age groups. Dietary polyunsaturated/saturated fatty acid ratios varied from 0.48 to 0.59. Cholesterol intakes ranged from 243 mg/d to 500 mg/d and when expressed per 4.2 MJ (1,000 kcal) were similar for males and females. The results of this intrapopulation cross-sectional study showed no significant relationship between dietary variables and total serum cholesterol and high-density lipoprotein cholesterol. However, the low percentage of respondents who met the prudent dietary guidelines add dietary risk factors to the already high prevalence of other major risk factors in this population.

Adolescent↗

PubMed1984

Nutritional value of diets of blacks in Ciskei.

This dietary study was part of a nutritional status survey carried out at the request of the Ciskeian Government to provide a baseline from which to formulate a nutrition policy. Nutrient intake was assessed by means of a 24-hour recall of food intake and a diet history, recorded for 750 subjects including children aged 6-23 months, 2-3 years and 7-8 years and lactating women. Nutrient intake was evaluated according to WHO standards. The prevalence of inadequate energy intake was high, especially among the 7-8-year-old children. For all age groups protein represented 11% of total energy intake, but was mainly of low quality. Calcium and iron intakes were low in all age groups, especially in lactating women. For all groups the most deficient vitamin was nicotinic acid, followed by riboflavin and ascorbic acid. This deficiency pattern was the result of a diet consisting predominantly of maize.

Adult↗

PubMed1981

Knowledge, attitudes and practices in relation to obesity and coronary artery disease. Results of a baseline study conducted among white parents and potential parents in the south-western Cape Province.

A baseline survey to determine the existing knowledge, attitudes and customs concerning different aspects of nutrition was conducted among adults in the south-western Cape Province. This was the first phase in a long-term research project launched with a view to developing a nutritional guidance programme in order to combat the high mortality rate attributed to coronary heart disease.

Adolescent↗

PubMedDate not supplied

Relation of family history and reversible risk factors to coronary heart disease prevalence in an Afrikaner community.

In a cross-sectional study of an Afrikaner community (n = 2,722 men and n = 3,173 women aged 25-64 years), family history of coronary heart disease (CHD) was associated with an adverse risk factor profile and with prevalent CHD. Men with myocardial infarction (MI) and a family history of CHD had higher total minus high density lipoprotein cholesterol (TC-HDLC) levels than men with MI but no CHD family history. In preliminary multiple regression analyses, family history of CHD appeared to exert its effect partly independently of known risk factors and partly dependently through age, TC minus HDLC, and HDLC. Even though their association with MI was weakened after entering family history into the models, the reversible risk factors (particularly TC minus HDLC, HDLC, and uric acid levels) continued to contribute to CHD. For MI in men, there was an interaction between family history of CHD and TC minus HDLC, to the extent that raised TC minus HDLC levels were adverse only in the presence of a positive CHD family history. The findings suggest coinheritance of high blood cholesterol and increased susceptibility to CHD. If confirmed in prospective studies, the interaction between family history and TC minus HDLC will have implications for cholesterol screening and management.

Adolescent↗