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O D Williams

Publications and source records attributed to O D Williams.

At least 55 records · Page 3Linked to original sources

High density lipoprotein cholesterol levels among US adults by selected demographic and socioeconomic variables. The Second National Health and Nutrition Examination Survey 1976-1980.

The distribution of serum high density lipoprotein cholesterol (HDL cholesterol) levels was determined on a nationally representative sample of 9,625 adults aged 20-74 years, as part of the Second National Health and Nutrition Examination Survey, 1976-1980 (NHANES II). Mean HDL cholesterol levels were higher in women compared with men (an age-adjusted difference of 8.9 mg/dl for whites and 4.4 mg/dl for blacks). HDL cholesterol levels were higher in blacks compared with whites (an age-adjusted difference of 7.4 mg/dl for men and 2.8 mg/dl for women). All differences were statistically significant (p less than 0.01). These relations remained after stratification by age, income, poverty index, education, body mass index, alcohol consumption, cigarette smoking, and physical activity. For whites, HDL cholesterol levels were highest in the highest category of earnings, whereas blacks generally had lower levels of HDL cholesterol with increased earnings. In a multivariate model, important predictors of higher HDL cholesterol levels were being female, being black, and reporting a higher frequency of alcohol consumption. Less strongly related were age, years of education, and reported high physical activity. Smoking and body mass index were strongly negatively related to HDL cholesterol levels. The findings in this national study support previous findings in selected populations in the United States.

Adult↗

Poland and US collaborative study on cardiovascular epidemiology. I. Introduction and baseline findings.

The Poland-US Agreement for Health Cooperation has as its goal the sharing of scientific information in cardiovascular disease epidemiology between the two countries. Patterns of cardiovascular disease and identification of risk factors were investigated through two large epidemiologic studies, the Pol-Monica Study in Poland and the US Lipid Research Clinics Program Prevalence Study in the United States. These two studies are described with regard to methodological issues, comparability of data collection procedures, and demographic and behavioral characteristics of the two populations involved. Mean blood pressure, lipids, and body mass indices of participants in these studies are also compared.

Adult↗

Poland and US collaborative study on cardiovascular epidemiology. II. Correlates of lipids and lipoproteins in men and women aged 35-64 years from selected Polish rural, Polish urban, and US samples.

Three diverse samples of men and women aged 35-64 years living in urban Poland, rural Poland, and the United States, are described and subsequently analyzed by multiple regression methods. Total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and the natural logarithm (ln) of triglycerides are treated separately as dependent variables, with several demographic, behavioral, and biologic factors as independent variables. In the analyses of total cholesterol, systolic blood pressure was statistically significant in men and women in all three samples, while Quetelet index, cigarette smoking, age, ethanol consumption, and education were significant in at least one of the samples. In the LDL cholesterol analyses, Quetelet index and cigarette smoking were the predominant variables; in the HDL cholesterol analyses, Quetelet index, cigarette smoking, ethanol consumption, and age were key variables; and in the ln triglycerides analyses, Quetelet index, cigarette smoking, education, and systolic blood pressure were significant.

Adult↗

Poland and US collaborative study on cardiovascular epidemiology. III. Correlates of systolic and diastolic blood pressure in men and women aged 35-64 years from selected Polish rural, Polish urban, and US samples.

Three diverse samples of men and women aged 35-64 years living in urban Poland, rural Poland, and the United States are described and subsequently analyzed using systolic blood pressure and diastolic blood pressure separately as dependent variables in multiple regression. Several demographic, behavioral, and biologic factors are included in the models as independent variables. Heart rate, Quetelet index, high density lipoprotein cholesterol, and the natural logarithm of triglycerides were statistically significant in accounting for variation in systolic pressure in men in all three samples, whereas only heart rate and Quetelet index were significant in women in all samples. In the analysis of diastolic pressure, Quetelet index, heart rate, and ethanol consumption were statistically significant in men in all three samples, while only Quetelet index and heart rate were significant in women in all samples.

Adult↗

Accuracy and precision of analyses for total cholesterol as measured with the Reflotron cholesterol method.

We compared plasma cholesterol measurements made with the Boehringer Mannheim Reflotron reflectance photometric analyzer in 1298 capillary blood samples with measurements made in venous blood samples collected at the same time and analyzed in four standardized Lipid Research Clinics laboratories. The Reflotron measurements averaged 0.8% to 7.8% lower than the laboratory values. Correlations (r) between the two sets of measurements ranged from 0.92 to 0.96. In some samples, however, the Reflotron values differed from the laboratory values by greater than or equal to 12%; the cholesterol concentrations in these samples tended to be higher than in those for which better agreement was observed. The smaller negative biases were observed when test strips were used that were calibrated with reference to the Centers for Disease Control Reference Method for cholesterol. The agreement between sequential Reflotron values averaged less than or equal to 4.3%. There was an average difference of less than or equal to 1.0% between Reflotron measurements made in each of two sequential capillary blood samples taken from a single finger puncture.

Cholesterol↗

Comparison of plasma lipids, lipoproteins and dyslipoproteinemia in Israel and the United States. The Lipid Research Clinics Program Prevalence Study.

Based on the common study design, protocol, and laboratory techniques used by the Lipid Research Clinics (LRCs), the study reported here compared the adult study populations examined by the U.S. LRCs and the LRC located in Jerusalem, Israel. A number of 2388 residents of Jerusalem were contrasted with 6528 examinees of the U.S. LRCs regarding their plasma lipid and lipoprotein cholesterol distributions. Marked differences between the U.S. and Jerusalem LRCs were observed in the plasma levels of lipids and lipoprotein cholesterol fractions. Mean total cholesterol concentrations were 2-8% higher in the U.S. compared to the Jerusalem sample. Low density lipoprotein cholesterol levels were higher by approximately 5-15% in the U.S. LRCs, a phenomenon more marked in men than women and in older compared to younger study participants. High density lipoprotein cholesterol values were also higher in the U.S. compared to the Jerusalem LRC, by approximately 10-14% in men and women. These differences were also more pronounced in older compared to younger participants. By contrast, median plasma total triglycerides (and by implication very low density lipoprotein cholesterol) were higher in the Jerusalem compared to the U.S. study participants. This difference ranged from 10-21% by age and sex. The correlations between the plasma lipid/lipoprotein measurements were similar in the two study populations. Only the degree of linear association between plasma total triglyceride and very low density lipoprotein cholesterol was different between the U.S. and Jerusalem, with a correlation coefficient of greater magnitude in the latter. Employing common cutpoints to define dyslipoproteinemia (DLP) observed differences in plasma lipid/lipoprotein distributions determined differences in the frequency of DLP categories between the U.S. and the Jerusalem samples. Higher proportions of Type IV and hypo-HDL were observed in Jerusalem compared to the U.S. By contrast, fewer individuals were classified as Type IIa, Type IIb, and hyper-HDL in Jerusalem relative to the U.S.

Adult↗

Populations and methods for assessing dyslipoproteinemia and its correlates. The Lipid Research Clinics Program Prevalence Study.

This article presents the basic methods and populations of the Lipid Research Clinics (LRC) Program Prevalence Study. The purpose is to provide a frame of reference for the other articles in this monograph; hence, the populations and major data collected are described briefly, as are procedures for enhancement of data quality and approaches to statistical analysis. More detailed descriptions for some procedures are included in the pertinent articles. The two sequential screening examinations of the Prevalence Study provided 60,502 participants from centers in the United States and Canada for the first phase and 13,852 for the second. The monograph is based on data from 11,657 white and 644 black participants aged 6 years or older screened at both visits.

Adolescent↗

Customary diet, anthropometry, and dyslipoproteinemia in selected North American populations. The Lipid Research Clinics Program Prevalence Study.

The intake of nutrients, determined by 24 hr diet recall, and body measurements were obtained in 8250 free-living white study participants divided into 20 to 49 and 50 + age groups for males and female nonusers and users of gonadal hormones. They were classified into dyslipoproteinemia (DLP) phenotypes: hyperHDL, hypoHDL, IIA, hpypoLDL, IV, and normal. The dyslipoproteinemia DLP phenotypes, compared with the normal, had biologically meaningful differences in nutrient intake and indexes of obesity that were most marked for males aged 20 to 49 years as shown in the table (below). Those with the hyperHDL phenotype were thinner and ingested more energy and more alcohol and less carbohydrate as percent kilocalories (%kcal). Individuals classified as hypoHDL were fatter and tended to ingest less energy and less alcohol as %kcal. Persons with the type II phenotype were fatter and ingested less energy. Those with hypoLDL tended to be thinner and ingested more energy. Individuals with the type IV phenotype were fatter, ingested less energy and carbohydrate and more alcohol as %kcal. Similar trends were observed in female nonusers of hormones aged 20 to 49 and to a lesser extent in the 50 + age groups and in female users of hormones. Dietary protein, cholesterol, total fat, and polyunsaturated and saturated fatty acids had no consistent associations with DLP phenotype, and sucrose and starch had no association independent of total carbohydrate. This is the first evidence of an association of customary diet and DLP phenotypes in the free-living population. Equating energy intake with energy expenditure, persons with the high-risk phenotypes, IIA, IV, and hypoHDL, compared with the normal, had decreased energy expenditure and were fatter, whereas those with the low-risk phenotypes, hyperHDL and hypoLDL, had increased energy expenditure and were thinner.

Adult↗

Coronary risk factors and their pathway of action through coronary raised lesions, coronary stenoses and coronary death. Multivariate statistical analysis of an autopsy series: the Oslo Study.

From 1972 to 1973, 16,202 Oslo men, aged 40 to 49 years, were examined for cardiovascular disease and coronary heart disease (CHD) risk factors. This report describes the results of autopsy examinations from 204 of 471 men who died in this cohort with regard to associations between selected risk factors and (1) raised coronary atherosclerotic lesions (RL), (2) coronary artery stenosis, and (3) CHD death. Total serum cholesterol and blood pressure levels were positively associated with all 3 measures of coronary atherosclerosis and its complications, both in univariate and multivariate analyses, whereas high-density lipoprotein (HDL) cholesterol was highly and inversely related. Triglyceride levels, cigarette smoking, social class and physical activity at work and at leisure were not significantly associated with either of the 3 measures. When RL was added to the model with stenosis as the dependent variable, the risk factors no longer appeared as independent; this is consistent with the hypothesis that these factors, when significant, work through the development of RL to produce stenosis. HDL cholesterol was the only risk factor independently and significantly associated with CHD death when RL or stenosis or both were put into the model for CHD. This points to the possibility of HDL cholesterol also working through mechanisms other than the prevention of RL and stenosis toward CHD death.

Adult↗

The ratio of plasma high-density lipoprotein cholesterol to total and low-density lipoprotein cholesterol: age-related changes and race and sex differences in selected North American populations. The Lipid Research Clinics Program Prevalence Study.

The distribution of the ratios of plasma high-density lipoprotein cholesterol (HDL-C) to total cholesterol (TC) and of HDL-C to low-density lipoprotein cholesterol (LDL-C) are presented for 6900 white and 495 black examinees greater than 4 years old. Measurements were obtained during the visit 2 survey of the Lipid Research Clinics (LRC) Program Prevalence Study, and correspond to a 15% random sample of 60,502 participants screened during the LRC visit 1 survey. Age-specific means, medians, and selected percentiles are given by sex and by gonadal hormone use in white women. Apparent in these cross-sectional data was a consistent age-related decline in the ratio of HDL-C to TC for white male participants, from a mean of 0.360 in the age group 5 to 9 to a mean of 0.211 in the age group 50 to 54. Thereafter the mean ratio increased slightly. In white women not using gonadal hormones the age-related decline in the ratio was only evident starting at the age group 35 to 39, from which it declines from 0.329 to 0.258 in the age group 55 to 59. White women using gonadal hormones showed very minor age-related changes in the HDL-C/TC ratio, varying around a mean of 0.300. The number of blacks examined was low and thus the racial comparisons must be interpreted with caution. For each gender, age-related trends were similar in black and white study participants. Black men, however, had a higher percentage of TC carried as HDL-C than white men in all age groups examined. Black women had a higher percentage of TC in HDL-C than white women only below age 20; in the adult age range no appreciable differences were seen. Pearson correlation coefficients between the lipid, lipoprotein, and lipoprotein ratios are presented. The ratio HDL-C/TC correlated highly with the ratio HDL-C/LDL-C (greater than 0.92 for all groups) and the former may be a more conveniently determined surrogate for the latter. Although not exhaustive regarding the information it conveys about a lipid pattern, the ratio HDL-C/TC has the advantage of summarizing complex associations into a single numerical approximation.

Adolescent↗

Common methods, different populations. The Lipid Research Clinics Program Prevalence Study.

The salient characteristics of the Lipid Research Clinics (LRC) Program Prevalence Study are presented, including an overview of its structure, the populations included and the common procedures used. Highlighted are the two sequential screening examinations that included 68,317 participants in 12 LRCs in the U.S. Canada and the U.S.S.R. for the first examination and 15,816 for the second. Several thousand more will be added as the thirteenth LRC completes its screening in Israel. Major data items are described briefly, as are data quality enhancement procedures. Procedures for plasma lipid determination, lipoprotein cholesterol, other clinical chemistries, nutritional intake assessment, and resting and stress electrocardiography are discussed. A discussion of the methodologic strengths and weaknesses of the findings of the LRC Program Prevalence Study is also included. This paper provides a frame of reference for the individual papers in this volume.

Adolescent↗

The association of plasma high-density lipoprotein cholesterol with dietary intake and alcohol consumption. The Lipid Research Clinics Prevalence Study.

We examined the associations of diet and alcohol consumption with levels of high-density lipoprotein (HDL) cholesterol using cross-sectional data from 4855 white participants, ages 20 years and older, seen at visit 2 of the Lipid Research Clinics Prevalence Study. There was a strong positive gradient of HDL cholesterol levels with reported amount of alcohol intake in both men and women, regardless of type of alcoholic beverage consumed. We found a difference in HDL cholesterol levels between the two groups of participants who reported no alcohol consumption during the past week. Those who said that they never drank had lower mean HDL cholesterol levels than those who reported that they did drink but had not consumed any alcohol during the past week. Weaker inverse relations (p < 0.05) were found between HDL cholesterol levels and intakes of total carbohydrate sucrose and starch (percent calories and grams). Dietary saturated, monounsaturated and polyunsaturated fat intakes were unrelated to HDL cholesterol levels; similarly, no association was seen for HDL cholesterol and total calories and total fat. Cholesterol intake (mg and mg/1000 calories) was generally unrelated to HDL cholesterol levels, except in women not taking exogenous gonadal hormones.

Adult↗

Plasma high-density lipoprotein cholesterol: association with measurements of body mass. The Lipid Research Clinics Program Prevalence Study.

Relationships between weight, height and ponderal indexes and plasma high-density lipoprotein (HDL) cholesterol and triglyceride were assessed by the Lipid Research Clinics Prevalence Study for 6865 white children and adults (3517 males and 3348 females). Overall, weight, weight/height, weight/height and weight/height were significantly and inversely associated with plasma HDL cholesterol levels and positively associated with plasma triglyceride levels. When the relationships of Quetelet index (weight/height) to HDL cholesterol were assessed by multiple regression analysis, including the explanatory variables of cigarette smoking, alcohol intake and exogenous estrogen hormone use, the Quetelet index was significantly and inversely associated with HDL cholesterol levels in children (by age 12-16 years) and adults of both sexes. After covariance adjustment for smoking, alcohol intake, hormone use and age, mean HDL cholesterol levels for individuals at the Quetelet tenth percentile were 3 mg/dl higher than for those at the fiftieth percentile, and these in turn were 3-4 mg/dl higher than for those at the ninetieth percentile. These differences in HDL cholesterol differences reported to be related to coronary heart disease mortality. Improved approaches to the primary prevention of atherosclerosis may be realized by a better understanding of the inverse relationship of body mass to HDL cholesterol levels.

Adolescent↗

Plasma high-density lipoprotein cholesterol, total cholesterol and triglyceride levels in 17-year-old Jewish residents of Jerusalem: a preliminary report. The Lipid Research Clinics Program Prevalence Study.

Preliminary data on plasma high-density lipoprotein (HDL) cholesterol, total cholesterol and triglyceride levels in 2565 teenage Jerusalem residents attending a military medical examination were analyzed. Mean HDL cholesterol levels were highest among male and female subjects whose fathers had immigrated from Europe and the Americas and lowest in those of Asian and of North African origin. Second-generation Israelis ranked intermediate between the Europeans and the other two groups. Total cholesterol levels were lowest in teenagers of both sexes whose fathers had come from North Africa, highest in subjects of European and of Israeli origin and intermediate in the Asians. Triglyceride levels were also lowest among North Africans of both sexes, but the Asian and Israeli groups had higher mean values than the Europeans. These findings show that patterns of lipid and lipoprotein levels previously observed in adult immigrants persist in a generation of native-born Israelis.

Adolescent↗