Milk protein has been implicated as a factor in the development of atherosclerosis. Significantly higher titers of antibodies (P < 0.0002) toward milk antigens were observed in patients suffering from coronary heart disease as compared to age matched controls. These hemagglutination titers were not sex related but may have been related to age. Specificity of the antigen-antibody reaction was demonstrated by a hemagglutination inhibition test. The complement fixation test was evaluated and was less sensitive than the tanned hemaggIutination test. Treatment with 2-mercapto-ethanol resulted in reduced hemagglutination titers, indicating that significant antibody activity may be due to IgM. A special application of the Combs test detected specific antibodies on the surface of tanned and coated RBC which did not otherwise produce detectable agglutination.

published_or_final_version / Community Medicine / Master / Master of Public Health

Prediction for future coronary artery disease (CAD) from high-density lipoprotein (HDL) and triglyceride (TG) measurements are based off of a single measurement that has been shown to be variable. To better determine risk for CAD based on blood lipids, studies in the postprandial state are warranted. To assess the reproducibility of TG clearance, 10 men underwent three trials of a 70g oral fat loading test with blood samples collected every two hours for eight hours. These trials were all scheduled at least one week apart. Men who had fasting TG concentrations > 250 mg - dL -' were excluded from the study. Each subject presented to the laboratory having abstained from exercise for 24 hours and alcohol 72 hours prior to the upcoming trial. Each subject was also provided with a standardized frozen dinner to eat the night before at a time which allowed the subject to be 12 hours fasted for the next days' trial. To specifically assess postprandial lipemia, TG concentrations were plotted against bi-hourly collection times to form a curve. The area under this curve was then calculated to determine PPL area. Itwas found that there was no significant difference in area under the TG curve (p = 0.25) for any of the three trials (1096 ± 168, 948 ± 105, and 995 ± 127 mg - dL -' - 8 • hr-' respectively for trials one, two, and three). Pearson correlations between trials were 0.79 for trials one and two, 0.82 for trials two and three, and 0.90 for trials one and three. Also, there was no significant difference in peak TG (p = 0.34) on each of the three trial days (167 ± 27, 150 ± 16, and 151 ± 19 mg • dL -1 in peak TG for trials one, two, and three respectively). Time taken to reach peak TG concentrations (p = 0.20) or time to return to baseline TG (p = 0.27) were not significantly different across three trial days. The men in this study reached peak TG concentrations in this study in 3.2 ± 0.5, 4.0 ± 0.4, 4.0 ± 0.3 hours respectively for trials one, two, and three. Time to return to baseline was 6.8 ± 0.6, 7.4 ± 0.4, 7.8 ± 0.4 hours for trials one through three respectively. Correlations between trials and the lack of a difference between trials using repeated measures ANOVA in regards to PPL area gives some preliminary evidence that some postprandial measures such as PPL area and can be reproduced across trials. However, the intra-individual variation was 19 ± 4% which provides no additional support for reproducibility of PPL. Additionally, results from this study, as well as all others pertaining to the study of reproducibility of PPL are specific to the protocol used and the method of interpretation. / School of Physical Education

Coronary heart disease (CHD) claims millions of lives every year worldwide. In the developed countries, a clear connection has been documented between a decline in CHD mortality and modifiable risk factor reductions. While raising awareness of CHD risk factors reduction is imperative, no valid instrument backed by robust psychometric data is available to measure people‘s awareness in this regard. In addition, especially among the Chinese population, despite many studies already conducted concerning awareness of CHD-related issues, inconsistency in how people define and measure this concept remains. This study aimed to develop a valid instrument that measures Hong Kong Chinese people‘s awareness of CHD risk factors reduction. The study involved two phases. Phase I involved qualitative data collection through 18 focus group interviews (n=100). Participants in this phase included members from three groups: (1) the low risk general public, (2) people having multiple CHD risk factors either with or without CHD, and (3) people who have been diagnosed of myocardial infarction. The objective of this phase was to identify key elements and to clarify the concept inherent in awareness, from which served as a basis to generate items to form the awareness instrument. Upon completion of this phase, three main categories were generated including: CHD knowledge, perceptions of CHD, and risk control efficacy. Under these main categories, twelve subcategories emerged. Under the category of CHD knowledge, the subcategories were: pathological causes of CHD, external forces in causing CHD, modifiable and non-modifiable risk factors, CHD trends, symptoms of CHD, and knowledge of CHD prevention. Under the category of perceptions of CHD, the subcategories were: perceived seriousness of CHD and perceived risk. Under the category of risk control efficacy, the subcategories were: planning of health actions, control over risk reducing behaviour, perceived opportunities to understand CHD, and chest pain appraisal/perceptions. A total of 70 items were generated to form the Awareness of Coronary heart disease Risk Factors Reduction (ACRFR) scale. The second phase of this study focused on the evaluation of the psychometric properties of ACRFR scale. The objective of this phase was to establish the validity and reliability of the instrument. It commenced with determining the content validity by expert review, followed by identifying the factor structure, construct validity and reliability. A good content validity index (CVI) of 0.84 was achieved. The factor structure of ACRFR was identified through exploratory factor analysis (EFA) data collected from a sample (n=232) of the three groups as described in phase one. The final results revealed a seven-factor model with 43 items accounting 49.5% of the total explained variance. The seven factors were: (1) CHD knowledge, (2) planning of health actions, (3) perceived ability to monitor health-related behaviour, (4) perception of risk, (5) perceived opportunities to understand CHD, (6) perceived seriousness of CHD, and (7) chest pain appraisal/perceptions. The factor structure of ACRFR was further cross-validated by confirmatory factor analysis (CFA) in another independent sample (n=225) of the three groups. Goodness of fit statistics fell within acceptable ranges: 2 / d = 1.6, RMSEA = 0.053, NNFI = 0.92, IFI = 0.93, CFI = 0.93. The factor model was further supported by hypothesis testing and known-groups comparisons. The results of hypothesis testing demonstrated significant correlations between ACRFR and other measures. Known-groups comparisons among subjects with MI, those with CHD and without CHD provided satisfactory evidence for construct validity. Reliability of this developed instrument, as estimated by the internal consistency Cronbach‘s alphas, ranged from 0.60 to 0.90 for each sub-scale and for the total scale was 0.82, and the test-retest reliability was 0.89, suggesting good instrument reliability. While current literature reveals no objectively devised conceptual definition of ACRFR and that no published instrument was made available for healthcare professions to enhance people‘s awareness of reducing CHD, this study fills these gaps. It is envisaged that this developed instrument could assist healthcare professional in accurately estimating people‘s awareness of risk factors reduction that could provide valid and reliable data that could inform future directions in CHD prevention and cardiac health promotion.

Source: Masters Abstracts International, Volume: 47-06, page: 3373. Advisers: Kelly Volcik; Sarah Baraniuk. Includes bibliographical references.

published_or_final_version / Medicine / Master / Doctor of Medicine

Objective: To determine the role of candidate gene polymorphisms in patients who sustained myocardial infarction at a young age and examine their relationship, if any, to risk factors. Since angiotensin II is known to play a pathophysiological role at the myocardial and vascular level, the genes to be studied are those regulating the renin angiotensin system and tissue metabolism. Design: The risk factors and genetic profile is described in 117 young Indians with myocardial infarction recruited over a period of thirty months (Dec 1997 - Jun 1999). Controls comprised 80 normal subjects with no clinical evidence of coronary heart disease (CHD) and with a normal effort response. The key features of this study are the selection of young subjects with myocardial infarction, (mean age 43 ± 6.8 years) in whom the possibility of a genetic basis for the disease was felt to be more likely since the confounding effect of age as a risk factor was reduced. Setting: Patients recruited 3 -12 months after myocardial infarction from Addington Hospital, Durban. This hospital subserves the Indian community in the north of Durban. The majority of patients were from the Phoenix settlement area. Results: 1. The clinical profile of the young Indian with myocardial infarction is a young man, slightly overweight with a high prevalence of risk factors, particularly smoking and diabetes, coupled with sedentary behaviour and risk-prone dietary patterns characterised by high red meat intake and low fruit and vegetable consumption, resulting in increased BMI and W/H ratios. 2. There were no differences in the patterns of gene polymorphism in the reninangiotensin system between the study and control groups. This finding extended across all candidate gene loci studied i.e. those involving aldosterone, G-protein, TGF-B and homocysteine metabolism. Serum triglycerides, haemoglobin AlC and urine microalbumin levels were elevated in the probands together with low HDL-C levels (p = 0.001). 3. A striking finding of this study was the substantial proportion of patients found to have diabetes mellitus, totalling 47% of the proband group. Of the 53 diabetic patients, (45 males and 8 females) four (3 males, 1 female) had impaired glucose tolerance. Cigarette smoking, a positive family history of hypertension/diabetes and a family history for premature CHD emerged as important risk predictors for MI. Conclusion: This study, the first to report candidate gene polymorphisms in young Indians with coronary heart disease, has shown no obvious association between the genetic loci studied and acute myocardial infarction. Instead a high prevalence of risk factors, particularly smoking and diabetes mellitus, coupled with coronary-prone behavioural patterns was observed. In the light of these findings, genome-wide screening of unaffected siblings of subjects with early onset CHD cannot be recommended in this population until common polymorphisms can be clearly identified as risk factors. Indeed this study again supports the dire need for early, school level, education in behavioural lifestyle patterns and disease predisposition. The Indian community is a very high-risk group who should be targeted, not for secondary, but for primordial disease prevention measures. The study does not rule out the role of other candidate gene polymorphisms in the pathogenesis of CHD in these subjects. The high prevalence of diabetes and insulin resistance suggests that studies of genes regulating glucose and lipid metabolism should be pursued. Such candidate genes should include genes for lipoprotein lipase and paraoxonase polymorphisms which may explain the dyslipidaemia patterns in this group. / Thesis (Ph.D.)-University of Natal, Durban, 2000.

Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2005. / Vita. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--La Crosse, 2002. / Includes bibliographical references.

M.Sc. (Psychology) / Please refer to full text to view abstract