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The importance of relative weight and body mass index to 14-yr mortality of 1233 white males of the Chicago Peoples Gas Company Study is analyzed by the inclusion of a quadratic term for weight in the multiple logistic function. The endpoints of death, all causes, CVR death, and CHD death are found to have a significant quadratic relationship to body mass index for the total cohort of 1233 men, while relative weight is found to have a quadratic relationship only with death, all causes. When the group is broken into men aged 40–49 and 50–59, body mass continues to show an important quadratic relationship to all three endpoints, while relative weight shows only an important quadratic relationship to death, all causes, among men aged 50–59. When the cohort is divided into smokers and nonsmokers, body mass index shows a significant quadratic relationship to all endpoints except CHD death among nonsmokers. Relative weight, on the other hand, is related quadratically only to total mortality in both groups. The weights corresponding to the lowest mortality are found to be about 25–35 per cent above the ideal published by the Metropolitan Life Insurance Company. Thus, for this cohort moderate overweight appears to be a sign of good health. Those individuals with the highest risk are those near the so-called ideal weight and those who are markedly obese, say with a relative weight above 150 or 160.

Several indices of diastolic blood pressure (DBP), based on three DBP readings at a single examination were assessed to determine which was best for predicting blood pressure status over the next 8 years. Measures of both level and variability were evaluated, singly and in combination. The results show that two or three DBP readings at one sitting permit a more accurate classification of future blood pressure status than a single reading. The mean of three readings was the best measure for classifying individuals as hypertensive, borderline or normotensive. When used with the mean of three readings, variability of DBP at one examination did not consistently yield further information concerning risk of future hypertension.

1974 WHO data on age-specific death rates due to definite and possible inflicted injuries (DII and PII) in 52 countries were studied. DII death rates for children under age one and for all ages were independent internationally. DII death rates for children aged 1–4 and for all ages were independent in developing countries, but in developed countries they came close to correlating. DII death rates for 1–4 yr olds were somewhat higher in developed countries; the infant rates were comparable. DII accounted for a greater proportion of deaths in children under 5 in developed countries. Analyses of PII rates gave less consistent results. Fatal child abuse in infancy may have different origins from the murder of older individuals. In industrially developed countries, some fatal abuse of children aged 1–4 may resemble the murder of adults.

This report, the third in a series on pulse pressure and pure systolic hypertension, examines the associations between blood pressure and the cardiovascular diseases and coronary heart disease, both cross-sectionally and prospectively, utilizing data from four Chicago epidemiologic studies, in an effort to determine whether or not a widened pulse pressure, or pure systolic hypertension, is an independent risk factor. In these analyses, blood pressure is divided into two components, one related to level and the other to pulse pressure, with pulse pressure redefined so that the association between pulse pressure and the prevalence of ECG abnormalities or mortality, indicates whether the endpoint is more strongly related to systolic or diastolic blood pressure. In these studies, blood pressure level is significantly related to both ECG abnormalities and mortality. In the cross-sectional analyses, pulse pressure is generally positively related to the prevalence of ECG abnormalities, indicating a stronger association for systolic blood pressure, and thus a possible association with pure systolic hypertension. However, in the prospective analyses, pulse pressure is generally not related to mortality, indicating an equal association with mortality for systolic and diastolic blood pressure in these studies. Thus, although the cross-sectional analyses generally support the hypothesis that a widened pulse pressure, or pure systolic hypertension, is an independent risk factor for the cardiovascular diseases and coronary heart disease, the prospective analyses do not.

The Jenkins Activity Survey (JAS), a self-administered and machine-scored questionnaire designed to assess the Type A behavior pattern described by Rosenman and Friedman, was included in an industry-based CHD risk factor screening program in the Chicago area. Data on 4108 white persons age 25–64 yr, categorized into four sex age groups, have been analyzed to investigate the relationship of the JAS Type A score to sex, age, socio-economic status (SES), CHD risk factors, prevalence of myocardial infarction, and compliance with recommendation to obtain followup medical evaluation. The following results were obtained. 1. 1. The Type A score is positively correlated with SES in all four sex age groups. 2. 2. After controlling SES, men do not differ significantly in mean Type A score from women, but both men and women age 45–64 yr have lower mean Type A scores than men and women age 25–44 yr. 3. 3. The number of cigarettes smoked per day is positively correlated with Type A score in men and younger women, but the magnitude of the correlation is very small. 4. 4. Prevalence of high blood pressure, defined as having elevated pressure or being treated medically for high blood pressure, is unrelated to Type A score in men and younger women but positively related in middle-age women after controlling for age, relative weight, and SES. 5. 5. The Type A score is weakly related to prevalence of hypercholesterolemia only in the total group of men age 25–44 yr; it is unrelated in older men and in women. Among persons not under medical treatment for CHD risk factors and without evidence of myocardial infarction, the Type A score is unrelated to concentration of serum cholesterol. 6. 6. The Type A score is unrelated to level of serum uric acid, plasma glucose after challenge, or relative weight. 7. 7. Compliance with a recommendation to obtain medical evaluation of suspect screening test results is unrelated to Type A score. 8. 8. Prevalence of myocardial infarction, as evidenced by Q-waves on the ECG or by history of physician-diagnosed heart attack, is positively related in middle-age men to Type A score after taking age, diastolic blood pressure, serum cholesterol, and cigarette smoking into account.

Two methodological problems in characterizing an individual's plasma glucose level are examined in this study. First, how large is the intra-individual variation of an individual's 1-hr post-load glucose level and for this estimated intra-individual variation what are the probabilities of misclassifying individuals based on a one-time measurement only of glucose level? Second, do different tests—i.e. fasting, 1-hr, 2-hr post-load, GTT—yield consistent ranking for the same individual? The first of these was explored with data on subsamples from the Chicago Peoples Gas Company (PG) study and the Chicago Heart Association Detection Project in Industry (CHA) study; the second, with data from the Chicago Coronary Prevention Evaluation Program (CPEP). For both the PG and CHA studies, the estimated ratios of the intra- to inter-individual variances were generally higher for post-load plasma glucose than blood pressure, heart rate, weight and serum uric acid. The conditional probabilities of misclassifying individuals into quintiles or deciles based on one measurement of 1-hr post-load glucose were also estimated from these data. These estimated probabilities indicate that the possible attenuation due to intraindividual variation cannot abolish a strong association; however, it may create some problem if the relationship is not very strong. Furthermore, both rank correlation and quintile classification analyses show that fasting, 1-hr and 2-hr plasma glucose level characterize individuals differently. Thus it is possible that the inconsistent results of previous studies, all using a one-time measure of plasma glucose, are partially due to the large intra-individual variation of this variable, and the use of methods that are not highly consistent in their classification of individuals.

With advancing age from youth on, there is an increase in mean serum cholesterol level of populations in "western" industrialized countries. Since serum cholesterol is one of the established major risk factors for premature coronary heart disease, it is important to explore the degree to which this age trend is physiologic or due to modern life styles. This study used cross-sectional data for 19,730 white men and 13,872 white women from the Chicago Heart Association Detection Project in Industry to investigate one aspect of this question: does weight explain the association between age and serum cholesterol, in particular whether older age is associated with higher serum cholesterol in the absence of overweight. The relationships among age, relative weight, and serum cholesterol were examined through assessment of mean serum cholesterol levels in 25 subgroups stratified by age (18-24, 25-34, 35-44, 45-54, 55-64) and by relative weight (less than 100, 100-109, 110-119, 120-134, greater than or equal to 135). Age and serum cholesterol were positively associated with each other. In women, it was a simple, linear relationship. In men, the degree of this positive association was less in people over age 35-44 than people in younger ages. These age-cholesterol patterns were present in men and women at desirable weight. However, in men aged 18-54, the positive association between age and prevalence of marked hypercholesterolemia (serum cholesterol greater than or equal to 250) was lower in people at desirable relative weight in comparison to those at higher relative weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Trends in age-specific mortality (10-year age groups, 5-74) for the U.S. population were reviewed for all causes of death from 1960 to 1980. The age-specific mortality rate generally declined. However, the following age-sex-color groups showed divergent mortality trends compared to those of other groups: (1) The death rates for white male teenagers and young adults (ages 15-24 and 25-34) increased during 1960s and stayed at the same level during 1970s. The ratio of male to female deaths for white teenagers and young adults (15-24 and 25-34) increased over both decades, although the mortality rate for white women age 15-24 increased during the 1960s. (2) Non-white men age 15-24 and 25-34 experienced biphasic mortality trends, with a rise peaking in 1971 and then a fall. (3) The mortality ratios, non-white to white men, age 25-34 and 35-44, were far higher then those of other age groups. (4) The mortality ratios, non-white males to females, increased steadily for all age groups, and those of age groups 15-24 and 25-34 turned up sharply. Selected causes of death (1960-1977) were reviewed to uncover reasons for the unfavorable mortality trends among males. The following causes contributed to rising mortality among males: (a) accidents, suicide, and homicide for white and non-white teenagers and young adults, age 15-24, 25-34 and 35-44; (b) suicide and homicide for non-white men age 45-54; (c) cirrhosis of the liver for white men age 35-44 and for non-white 25-34, 35-44 and 45-54; (d) malignant neoplasms for white men age 35-44 and for non-white age 45-54.

Although hypercholesterolemia is established as a major risk factor for coronary heart disease, the finding in some epidemiological studies of no association between serum cholesterol and all causes mortality suggests that serum cholesterol may be inversely related to the risk of death from non-cardiovascular causes, e.g. cancer. This possibility led to the examination of this question in middle-aged white males from the Chicago Peoples Gas Company and Chicago Western Electric Company studies, and in middle-aged white males and females from the Chicago Heart Association Detection Project in Industry. In each of these studies, there was no significant association between initial serum cholesterol level and subsequent mortality from cancer, or from causes other than cancer and the cardiovascular diseases in men. There was, however, a significant inverse association with other causes of death in women. When the cancer deaths were examined by site, there was a significant inverse association between serum cholesterol and deaths from sarcoma, leukemia and Hodgkin's disease in the Western Electric men and one that was nearly so in the Chicago Heart Association men. Serum cholesterol was not significantly related to lung cancer, colorectal cancer, oral cancer, pancreatic cancer, or to all other cancers combined in any of the three studies in men or in women. There was, however, the suggestion of a positive association for breast cancer in women. Thus, the results of these three studies do not generally support the hypothesis of an inverse association between serum cholesterol and cancer in urban middle-aged white American males and females.

Because systolic blood pressure rises more sharply than diastolic blood pressure for those middle aged and beyond, leading to an increasing prevalence with advancing age of elevated systolic blood pressure without elevated diastolic pressure, i.e. so-called pure systolic hypertension, the question arises as to whether or not factors that have been shown to be related to blood pressure and hypertension are related to pure systolic hypertension or to 'classical' hypertension, i.e. hypertension defined solely by the level of the diastolic pressure. This question was examined in four Chicago epidemiologic studies by examining the associations between several variables and pulse pressure, with pulse pressure redefined so that the association between a variable and pulse pressure indicated whether the variable was more strongly related to systolic or diastolic blood pressure. In these four studies, glucose, heart rate and cigarette use tended to show a stronger association with systolic pressure, suggesting a possible association with pure systolic hypertension, while hematocrit, serum cholesterol, and uric acid tended to be more strongly associated with diastolic pressure, or equally associated with systolic and diastolic pressure, suggesting an association with 'classical' hypertension. Relative weight tended to be more strongly associated with systolic pressure under the age of 35 and more strongly associated with diastolic pressure after age 45.

1. 1. As in the preceding cross-sectional study [1], four multivariate statistical methods —partial correlation, multiple cross classification, multiple logistical regression, and multiple linear regression—were used to evaluate the relationship between seven variables and blood pressure in over 21,000 employed men and women, white and black, ages 25–44 and 45–64 surveyed in almost 100 Chicago companies and organizations. The analyses were carried out separately for eight age-sex-race groups. The seven variables were relative weight, resting heart rate, plasma glucose one hr after 50 g oral load, serum uric acid and cholesterol, current cigarette smoking habit, and age. 2. 2. Consistent with the findings of the preceding report, the first three of these variables—relative weight, heart rate, and plasma glucose—were independently related to blood pressure with a high degree of consistency, with p values for statistical significance ≤0.01 or ≤0.001 in the great majority of analyses. 3. 3. Serum uric acid—a variable not evaluated in the preceding report—was also independently related to blood pressure in a great majority of the analyses with p values of ≤0.01 or ≤0.001. 4. 4. The findings with respect to serum cholesterol and blood pressure were generally negative, except for white males, an intriguing finding in view of a similar result from the preceding study. 5. 5. No positive relationship was found between cigarette smoking and blood pressure. 6. 6. Even within the narrow age bands studied—ages 25–44 and 45–64—age was significantly related to blood pressure in a great majority of analyses ( p values ≤0.01 or ≤0.001), independent of the six other variables. 7. 7. As in the preceding paper, when multivariate regression equations and their coefficients, computed from this experience of an entire age-sex-race group, were used to calculate an expectation of elevated blood pressure for each person, and then persons were ordered from low to high in expectation, a high proportion of all persons with recorded elevations of blood pressure were in the highest decile and quintile of expected prevalence—e.g. for persons age 25–44 in the four sex-race groups, from 45 to 56 per cent of observed cases with diastolic pressure ≥95 mm Hg. were in the highest quintile (20 per cent) of expected prevalence. The observed prevalence of elevated blood pressure was many times greater for the highest quintile of expected prevalence than for the lowest. A similar but less effective concentration of cases of elevated blood pressure was obtained with the multiple cross classification method, by dichotomizing five of the independent variables and identifying the substratum with any three, four or all five high.

An epidemiologic analysis was accomplished of cardiovascular-renal mortality by age, race, sex, and occupation for the Chicago population aged 25 to 64 in 1951 and 1953. The following were the principal findings: 1. Arteriosclerotic heart disease (ASHD) death rates were severalfold higher in men than women. This sex differential was greater in whites than nonwhites, chiefly because of the higher mortality rates in nonwhite females. Nonwhite male death rates for ASHD were similar to those for white males. No significant occupation group differences in age-specific ASHD death rates were observed for middle-aged men. 2. Hypertensive disease death rates were severalfold higher in nonwhites than whites, without a gross sex differential. This pattern also prevailed for cerebrovascular diseases, nephritis and nephrosis. An evaluation was made of deaths attributed to Other Myocardial Degeneration and Other Diseases of the Heart, particularly in relationship to mortality patterns for ASHD and hypertensive disease. An analysis was also accomplished of deaths certified by the coroner's physicians. Consideration was given to the bearing of the findings upon current theories concerning the etiology of these diseases.

Death rates due to cardiovascular-renal and heart diseases, including coronary heart disease, were moderately lower in middle-aged foreign-born than in all Chicago white males. These rates were considerably higher for the foreign born Chicago males than for age-matched men in the corresponding countries abroad. Coronary heart disease death rates were higher in middle-aged white American males than in Japanese-Americans, and American-Indians, and Chinese-Americans.

1. 1. An epidemiologic analysis of coronary heart disease and other cardiovascular-renal diseases was accomplished, utilizing the accumulated medical and personnel records on the entire male labor force aged 50 to 59 years (784 men) of a Chicago utility company. 2. 2. Observed prevalence and incidence rates for coronary heart disease were 71/1,000 and 61/1,000 for 4 years, respectively. 3. 3. The over-all mortality rate from coronary heart disease was 25/1,000 for 4. 4 years. The mortality rate in those free of coronary heart disease at the onset of the study was 17/1,000 for 4 years. Of all deaths, 47 per cent occurred suddenly. 5. 4. Hypertension, obesity, diabetes mellitus, and suspected coronary heart disease were associated with increased incidence rates of definite coronary heart disease. 6. 5. Prevalence rates of hypertension and obesity were similar in sociologic subgroups of the total population under study. Sociologic stratifications were made based on nativity, residence, military experience, education, occupation, physical activity of work, indoor versus outdoor work, and type and amount of income. 7. 6. Coronary heart disease incidence rates were similar in the sociologic subgroups, with the exception that significantly lower rates were observed in the foreign-born than in the native-born. Coronary heart disease incidence rates are high in all strata of the middle-aged male population in the United States.

1. 1. Four multivariate statistical methods—partial correlation, multiple cross classification, multiple logistic regression, and multiple linear regression—were used to study the relationship between six variables and blood pressure in over 13,000 men and women, white and black, ages 30–44 and 45–64 surveyed in two low-income Chicago communities. The analyses were carried out separately for eight age-sex-race groups. The six variables were relative weight, resting heart rate, plasma glucose 1 hr after 100 g oral load, hematocrit, serum cholesterol and age. 2. 2. The first three of these variables—relative weight, heart rate, and plasma glucose —were independently related to blood pressure with a high degree of consistency, with p values for statistical significance ≤0.001. 3. 3. Hematocrit was independently and additively related to diastolic—but not to systolic—pressure for the four age-race groups of women, but only for one of the four age-race groups of men. 4. 4. The findings with respect to serum cholesterol and blood pressure were generally negative. 5. 5. Even within the narrow age groups studied—ages 30–44 and 45–64—age was significantly related to systolic level particularly ( p values ≤0.01 or ≤0.001), independent of the five other variables. 6. 6. When multivariate regression equations and their coefficients, computed from the experience of an entire age-sex-race group, were used to calculate an expectation of elevated blood pressure for each person, and then persons were ordered from low to high in expectation, a high proportion of all persons with recorded elevations of blood pressure were in the highest decile and quintile of expected prevalence—e.g. for persons age 30–44 in the four sex-race groups, from 47–69 per cent of observed cases with diastolic pressure ≥95 mm Hg were in the highest quintile (20 per cent) of expected prevalence. The observed prevalence of elevated blood pressure was as much as 20 times as high for the highest quintile of expected prevalence as for the lowest. A similar but less effective concentration of cases of elevated blood pressure was obtained with the multiple cross classification method, by dichotomizing four of the independent variables and identifying the substratum with any two, three or all four high.

Investigations involving comparisons of populations, as well as intervention studies on groups, both under free-living and metabolic ward conditions, unequivocally demonstrate significant relationships between lipid components of the diet and serum cholesterol levels. However, low order or no correlations have been reported when these dietary variables and serum cholesterol are related for individuals. Several factors underlie this apparent paradox. This paper discusses at length the role of intra-individual variation in this apparent paradox, with particular emphasis on the errors caused by intra-individual variation in classification and estimation of correlation coefficients. Methods are presented for estimating the number of measurements required to achieve a suitable degree of accuracy for both classification and correlation analysis. Based on these theoretical considerations and practical examples illustrating their application, an assessment is made of commonly used dietary survey methods in terms of their appropriateness for measuring individual dietary intake. Suggestions are made for improving the design and methods of nutritional surveys, especially with regard to reducing errors introduced by intra-individual variation.

Studies of possible association between asymptomatic hyperglycemia and coronary disease were conducted among middle-aged employed men in Chicago. In one cohort, frequency of ECG abnormalities at baseline was examined among men at different glucose levels. In univariate analysis, those at the highest glucose levels had higher rates of ECG evidence of CHD, but this association did not remain when such factors as age, blood pressure, weight, cholesterol and cigarettes were taken into account in multivariate analysis. Among the studies, long-term follow-up to mortality (10, 13 and 15 yr) showed inconsistent findings on association of hyperglycemia and subsequent death. In one cohort (Gas Company men followed for 10 yr after a 1-hr post-load glucose determination) a positive glucose-mortality association was found in both univariate and multivariate analysis. But in the two remaining cohorts (Gas Company 13 yr after casual glucose determination and Western Electric 15 yr after 2-hr post-load determination), no such association was found. While differences in method and sample size as well as other limitations may have contributed to the differences observed, the inconsistency of the findings do not permit a conclusion that asymptomatic hyperglycemia is a positive coronary risk factor.

This report, the second in a series on pulse pressure and pure systolic hypertension, examined in prospective analyses the associations between both the initial values of five variables and the changes in these variables and pulse pressure, utilizing data from three Chicago epidemiologic studies, in order to determine whether variables known to be related to blood pressure and hypertension are related to pure systolic hypertension or ‘classical’ hypertension. In these analyses, follow-up pulse pressure, which was measured from 2–5 years after the initial measurement of the other variables, was redefined so that the association between the initial value or change and pulse pressure indicated whether the initial value or change was more strongly related to follow-up systolic or diastolic blood pressure. In these three studies, only the initial value for cigarette use had a consistent positive association with follow-up pulse pressure. Change in heart rate was generally positively related to follow-up pulse pressure, while the initial value was not. For relative weight and serum cholesterol, both the change and the initial value tended to be negatively related. For glucose, the association was not consistent for either the initial value or the change. The results from these prospective analyses thus suggest that cigarette use is related to pure systolic hypertension, rather than ‘classical’ hypertension.

Because systolic blood pressure rises more sharply with age than diastolic blood pressure, leading to an increasing prevalence with advancing age of elevated systolic blood pressure without elevated diastolic pressure, i.e. so-called pure systolic hypertension, the question arises as to whether or not pure systolic hypertension has its own etiology and pathogenesis. Since pure systolic hypertension is characterized by a widened pulse pressure, the present report examined the association between relative weight and pulse pressure, both cross-sectionally and prospectively, in addition, to the association between relative weight and the level of blood pressure, in four Chicago epidemiologic studies. The positive association between relative weight and the level of blood pressure in these studies, in both cross-sectional and prospective analyses, reaffirms the finding in previous studies of a positive association between weight and blood pressure and the prevalence and incidence of hypertension. However, the results of these studies did not generally support the hypothesis that relative weight is related to pulse pressure, and thus possibly to pure systolic hypertension.

Previous studies have indicated that heart rate and post-load plasma glucose are independently related to blood pressure. This study explores these relationships further. Of 39,665 adults screened in Chicago firms between late 1967 and early 1973, 27,117 white men and women aged 18–64, not receiving drug treatment for hypertension or diabetes, are the focus of this study. Within each age sex group, the sample was stratified by heart rate. Within each heart rate group a multiple linear regression analysis was done with blood pressure the dependent variable and plasma glucose, serum cholesterol, relative weight, age and number of cigarettes per day the independent variables. Within each age sex group glucose was progressively higher with higher heart rates. In addition, the glucose coefficients tended to be larger at higher heart rates, especially in men age 25 and over, i.e. the glucose blood pressure association was stronger in men with high heart rate. These results suggest that there exists a population of individuals with the triad of high blood pressure, high heart rate, and high glucose whose hypertension may have a distinct etiology and/or pathogenesis.

Among the 40,000 employed men and women screened in Chicago industry, 7841 white men age 40–59 formed the cohort studied to determine significance of asymptomatic hyperglycemia for coronary disease. In cross-sectional analysis of frequency of ECG abnormalities, those in the upper 2 1 2 % of the glucose distribution had higher rates of such abnormalities than the rest of the group, and men in the highest quintile likewise had higher rates of ECG abnormalities than were seen in the lowest quintile. Analysis of these data using the multiple logistic showed inconsistent positive association of glucose with prevalence of ECG abnormalities defined by the Whitehall and Pooling Project criteria, but no association with definite MI, on ECG. In 5-yr mortality follow-up, while men with overt diabetes experienced coronary death rates 2–3 times higher than those without such a diagnosis, similar univariate analysis that excluded diagnosed diabetics showed no association between glucose level and coronary mortality. In multivariate analysis as well, no association between initial glucose and subsequent coronary or cardiovascular mortality was seen, although all causes mortality rates were significantly related to glucose levels. The inconsistent results between univariate and multivariate analyses, as well as between cross-sectional and prospective findings, do not support a conclusion that asymptomatic hyperglycemia is a major coronary risk factor.