New knowledge on the pathogenesis of the acute coronary syndromes provides the clinician with a better understanding of these important, often life-threatening, events and opens up new ways of managing them. The identification of the vulnerable plaque whilst important and possible pathologically still requires elaborate and often invasive methods. The central role of inflammation and the platelets in these syndromes has already been translated into practical therapeutics. Identifying and predicting which plaque would rupture and thereby facilitating the formation of an acute obstructive thrombus continue as major challenges to the clinician, but, in the meantime, regressing and stabilising these plaques are achievable goals.
Several risk factors for cardiovascular disease amongst a sample of urban Chinese women were investigated. These factors included body mass index (BMI), waist hip ratio, total blood cholesterol (TC), HDL-cholesterol and Lp(a) levels, blood pressure, cigarette smoking, family history of chronic disease, dietary habits and frequency of selected food intake. The subjects were found to have coronary risks with respect to BMI and TC level, both of which increased with age of the women. Hypertension, HDL-cholesterol and Lp(a) levels appeared not to pose as risk factors amongst these subjects. Dietary habits and intake showed significant correlations with subjects' BMI status. Health promotion is called for towards reducing the modifiable coronary risk factors.
733 senior civil servants comprising 520 males and 213 females with a mean age of 44 years (range 25-56 years) were screened for their health status. The sample population comprised of 67.9% Malays, 22.5% Chinese, 9.1% Indians and 0.4% other ethnic origins. The subjects' medical histories were recorded and a full medical examination including anthropometric measurements (weight, height, waist and hip circumference), blood biochemistry and urine analysis, chest X-ray and electrocardiograms were done. The results obtained showed that 36.0% of the study population were overweight with 6.5% being obese. Of this 32.0% had central obesity. 15.2% of the subjects had systolic hypertension (systolic BP > or = 140 mmHg) whilst 27.6% had diastolic hypertension (diastolic BP > or = 90 mmHg). Hyperlipidaemia was common, with 75.2% subjects having raised cholesterol, 19.9% raised triglycerides, 50.2% raised LDL-C, 74.6% raised TC:HDL-C and 26.6% raised LDL:HDL-C. An elevated blood glucose was found in 8.4% subjects, whilst urine sugar was detected in only 2.6%, and a raised uric acid was found in 2.8% subjects. The prevalence of hypertension, raised blood glucose and hyperlipidaemia increased with age with more males affected than females. Although hypercholesterolaemia appeared more frequently amongst the Malays, the Indians, by comparison had the highest prevalence for a raised LDL:HDL-C ratio, a reflection of the increase in LDL-C and a concomitant decrease in HDL-C. The latter findings indicate that the Indians are at greater risk for the development of coronary heart disease than the Chinese and Malays. In addition, the mean levels of serum cholesterol found in this study seemed to have exceeded the levels found in populations in the industrialised countries such as the USA. There is thus an urgent need for more public health campaigns aimed at the reduction and control of such coronary risk factors.
From available studies, there appears to be a racial preponderance of coronary artery disease (CAD) among Indians when compared to other ethnic groups. We found that this racial difference exists even in a young Asian population with premature atherosclerosis. In this small series, these racial differences could not be explained by the commonly known risk factors for coronary artery disease--smoking, hypertension, diabetes and hypercholesterolaemia, findings similar to those found in older patients elsewhere. Only fasting triglyceride levels were significantly higher among young Indians compared to non Indians (p less than 0.02) although the importance of this finding as a risk factor for CAD remains controversial. The majority of these young patients were treated medically and their one year survival was good.
One hundred consecutive patients attending the UKM (Universiti Kebangsaan Malaysia) Cardiology Clinic completed a questionnaire enquiring about their own assessment of their knowledge about their illness, their awareness of cardiac risk factors and their expectations in their management. Only 11% of our patients had graduated from tertiary education. 59% of our patients were being treated for ischaemic heart disease. Although only 28% of our patients considered having considerable knowledge of their illness, a majority of our patients were aware of cardiac risk factors. This was independent of the formal education achieved. However this awareness did not necessarily result in appropriate behaviour; 32% of patients admitted to smoking despite being aware of the harmful effects of smoking. 74% of our patients expected a cure from their doctors; only 37% of our patients thought they required medication indefinitely. Thus, patients could be made aware of their illness regardless of their formal educational status. However this may not necessarily result in appropriate behaviour. The high expectations which the patients have of their doctors is unrealistic and may be detrimental to appropriate long-term management of their chronic illness.
Study site: Cardiology Clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM)
Over a thousand subjects who visited a city private medical clinic for health screening and advice were examined for their lipid profile and other cardiovascular risk factors. The mean TC, TG, LDL-C and HDL-C were 5.43, 1.45, 3.61 and 1.15 mmol/l. Their derived ratios viz, TC:HDL-C and LDL:HDL-C were 5.11 and 3.43 respectively. The prevalence of hyperlipidaemia was moderately high. Of the subjects studied 58.5% had elevated serum cholesterol, 14.8% had raised triglycerides, 64.9% had raised LDL-C and 20.8% had low HDL-C. Male subjects generally showed higher mean values and abnormality frequency in TC, TG, LDL-C, TC:HDL-C and LDL:HDL-C as compared to female subjects. Although significant ethnic differences were not detected for certain lipid parameters (e.g. TC, TG and HDL-C), the Indians appeared to have higher mean lipid values (except HDL-C), and higher percentage abnormality for all the lipid parameters as compared to the Chinese and the Malays. In correlation studies, the following lipid parameters:- TC versus TG, LDL-C, TC:HDL-C; TG versus TC:HDL-C and LDL:HDL-C; LDL-C versus TC:HDL-C and LDL:HDL-C; were positively correlated. On the other hand, TC versus HDL-C, TG versus HDL-C, LDL-C and HDL-C, and HDL-C versus TC:HDL-C and LDL:HDL-C were negatively correlated. The coronary risk factors which generally showed positive correlations with lipid parameters were BMI and blood pressure. Positive correlations were also recorded between fasting blood glucose and TG; uric acid with TG, TC:HDL-C and LDL:HDL-C. In contrast, risk factors of negative correlations were observed between HDL-C and the coronary risk factors of BMI, diastolic blood pressure and uric acid. Smoking showed raised per cent lipid abnormality for TG, HDL-C, TC:HDL-C and LDL:HDL-C. Alcohol consumption also increased the mean level and abnormality frequency for TG. The implication of this investigation is discussed.
A six-month survey of 828 patients admitted to the Coronary Care Unit (CCU) of the General Hospital, Kuala Lumpur was carried out to ascertain whether the smoking habits of the patients predisposed them to definite coronary events and its immediate outcome i.e. early mortality (within seven days). The various ethnic groups were also screened to determine if they were at increased risk to coronary events in relation to other known risk factors. Three hundred and eleven patients - 239 males, and 72 females - had confirmed acute myocardial infarctions of whom 190 were smokers (172 males, and 18 females). Sixty-nine infarct patients died within the first seven days post-Ml: 35 were smokers (50.7%). Two-hundred and eighty other patients had non-infarct coronary events. Of these, 167 were smokers. In contrast, only 99 out of 237 patients admitted for non-coronary events, were smokers. It thus appeared that patients admitted to the CCU for suspected cardiac events had a greater incidence of confirmed acute myocardial infarction or acute coronary events if they were smokers (p < 0.001). Mortality from these coronary events was not seen to increase among smokers in this population sample. Women who smoked as a whole, were not found to be at increased risk to coronary events, but women smokers 60 years and older were shown to be at increased risk to developing confirmed coronary events (p < 0.01).
In a prospective case-control study over a two-year period involving 1006 women, 264 women with acute myocardial infarction (AMI), 305 with non-infarct acute coronary syndromes (CAD) were compared with 437 women with no coronary heart disease (Controls), to determine the relationship between cigarette smoking and other risks factors with coronary heart disease. A history of current cigarette smoking was strongly associated with the risk of coronary events for both AMI And CAD (p less than 0.001). 23.9% of patients with acute coronary syndromes were current smokers, compared with only 12.8% among controls. Overall, women smokers had about a two-fold increase in risk for all coronary events. Younger women smokers (less than 40 years) and those between 61-70 years had particularly higher risks (10.3 and 2.7 times respectively (p less than 0.01, p less than 0.02). A dose-response pattern of increased AMI risks (from 2.0 to 2.9 times) among women smokers was also found, corresponding to the number of cigarettes smoked per day (p less than 0.05). Other significant coronary risk factors established were: postmenopausal status (OR 6.5), diabetes mellitus (OR 5.1), hypertension (OR 1.6), family history of premature coronary heart disease less than 50 years (OR 1.3) and use of oral contraceptive pills (OR 1.4). Our results thus emphasize that cigarette smoking is an important determinant of acute coronary events even among Malaysian women.
The purpose of the study is as a preliminary outline of the effectiveness of initiating high-risk individuals into the Health Farm concept in the primary prevention of coronary artery disease (CAD). Thirty-five (35) Army personnel, all male, with risk-factors for CAD were brought together on a Health Farm concept to go through a predesigned ten-day Farm programme comprising CAD risk-assessment, comprehensive medical examination, relevant blood chemistry analysis, physical fitness evaluation, individualised weekly exercise routine, physical fitness workouts, individualised diet, lectures, group discussion and individual counselling. Description of the participants (as measurements of various relevant parameters) are made at the start and as participant-achievement. The results show general participant-compliance to the programme which was reflected by significant changes in weight (p < 0.005), percentile VO2Max (p < 0.005), percentile push-ups (p < 0.005) and girth-difference (p < 0.005). The study showed that the Health Farm concept is effective in initiating high-risk individuals into lifestyles conducive to the primary prevention of CAD. Sustained results towards primary prevention of CAD can be expected with compliance to a long-term follow-up that has been identified and to which participants have been made aware of. Other previous intervention studies are briefly discussed.
Silent myocardial ischaemia is now well-recognised in patients with symptomatic coronary artery disease. Its pathogenesis remains speculative, though diminished sensitivity to pain is thought to be one of the mechanisms involved. Because cardiovascular autonomic dysfunction occurs frequently in diabetic patients, we postulate that it contributes towards painless myocardial ischaemia among them. Forty consecutive diabetic (type II) male patients and ten normal volunteers were studied. Using 5 previously-validated noninvasive tests for autonomic dysfunction, 14 of these diabetic men had definite autonomic neuropathy (at least 2 abnormal tests). All 50 subjects were then exercised on a motor-driven treadmill to either exhaustion or chest pains. Thirty-three diabetic subjects were tested positive, with significant (greater than 1 mm) ST segment depression over at least 2 contiguous leads. Of these, 18 were associated with typical angina but the other 15 stopped because of fatigue or exhaustion (ie painless). Thirteen subjects who had definite autonomic neuropathy (AN+) had positive exercise ECG tests-10 had painless ischaemia, and only 3 had angina. This contrasted with 15 patients who had painful ischaemia and 5 who had painless ischaemia among the group without (AN-)autonomic dysfunction (p = 0.0047, Fisher's exact test). There were no significant differences among the various groups for peak rate-pressure-product, all subjects attaining similar maximal oxygen consumption states during which ischaemic ST segment changes were noted (painful AN+: 21917 +/- 4753; painless AN+: 20117 +/- 6752; painful AN-: 16544 +/- 4063; painless AN-: 22220 +/- 4341, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)
A total of 86 unrelated Malaysian patients with familial hypercholesterolaemia (FH) were studied for mutations in their low-density lipoprotein receptor (LDL-R) gene. Amongst them, 23 had a LDL-R gene mutation, while none having an Apolipoprotein B-3500 (Apo B-3500) mutation. Patients with the LDL-R gene defect appeared to have a higher level of low-density lipoprotein cholesterol (LDL-C), an increased incidence of xanthomas and coronary heart disease (CHD), but no relationships were found between the type of LDL-R gene mutations and their lipid levels or clinical signs of CHD. In contrast to Western data, our findings seemed to indicate a predominance of mutations in the ligand binding domain and an absence of Apo B-3500 gene mutation. The latter finding may offer a genetic basis as to why Asian patients with familial hypercholesterolaemia have lower LDL-C levels and less premature CHD than their Western counterparts.
Coronary heart disease (CHD) is the leading cause of death in Malaysia, despite its status as a developing country. The rural population is thought to be at low risk.
STUDY OBJECTIVE: To examine the hypothesis that the higher rates of coronary heart disease (CHD) in Indians (South Asians) compared with Malays and Chinese is partly because of differences in antioxidants (vitamins A, C, and E, and selenium) and pro-oxidants (iron).
DESIGN: Cross sectional study of the general population.
SETTING: Singapore.
PARTICIPANTS: Random sample of 941 persons aged 30 to 69 years.
MAIN RESULTS: There were moderate correlations between vitamin A and vitamin E, and between these vitamins and selenium. Mean plasma vitamins A and E were similar by ethnic group. Vitamin A concentration for Indians were (men 0.66 and women 0.51 mg/l), Malays (men 0.67 and women 0.54 mg/l), and Chinese (men 0.68 and women 0.52 mg/l). Vitamin E concentrations for Indians were (men 12.9 and women 12.8 mg/l), Malays (men 13.6 and women 13.3 mg/l), and Chinese (men 12.6 and women 12.6 mg/l). In contrast, mean plasma vitamin C concentrations were lower in Indians (men 5.7 and women 6.9 mg/l) and Malays (men 5.1 and women 6.4 mg/l) than Chinese (men 6.3 and women 8.4 mg/l). Mean serum selenium was lower in Indians (men 117 and women 115 micrograms/l) than Malays (men 122 and women 122 micrograms/l) and Chinese (men 126 and women 119 micrograms/l). Mean serum ferritin was much lower in Indians (men 132 and women 50 micrograms/l) than Malays (men 175 and women 85 micrograms/l) and Chinese (men 236 and women 92 micrograms/l).
MAIN CONCLUSIONS: Lower vitamin C and selenium in Indians, particularly in combination, could play a part in their increased risk of CHD. Vitamins A and E, and ferritin (iron) have no such role. Lower vitamin C in Indians and Malays is probably because of its destruction by more prolonged cooking. In Indians, lower selenium is probably because of a lower dietary intake and the much lower ferritin to a lower dietary intake of iron and its binding by phytates.
The Well Man & Well Woman's Clinic in Ipoh Hospital provides screening for coronary risk factors and early detection of cancer. This retrospective review of 1095 patients screened between April and December 1995 showed 48% had one or more coronary risk factors--1 risk (29%), 2 risks (14%), 3 or more risks (5%). Modifiable risks included hypertension (10%), obesity (9%), diabetes mellitus (8%) and smoking (7%). Sixteen abnormal Papanicolaou smears and six cancers (three cervical, two breast and one ovarian) were detected. Public response was good. There is a need for clinics offering comprehensive screening in Malaysian primary health care.
Study site: The Well Man & Well Woman's Clinic in Ipoh Hospital
Mortality from ischaemic heart disease in Singapore is now reaching comparability with the West. For the early 1980s, rates for Indians and Malays were higher than in U.S.A. and England and Wales and while those for Chinese were lower they were considerably higher than in Japan. In keeping with this the levels of the major risk factors in Singapore are now comparable to the West. Cigarette smoking in males is virtually the same as in Britain, while the proportion of hypertensives on medication is higher than in the West. The main cause for concern is the current high levels of serum cholesterol in Singapore and strenuous health education efforts are needed to bring about dietary changes.