Diabetes among men in a general population. Prevalence and associated physiological findings.

A random sample of 281 men, aged 30 through 69, resident in the community of Tecumseh, Mich, was studied with the use of standard glucose tolerance tests, including serum insulin assays and fasting serum lipid concentrations. Diagnoses of diabetes and probable diabetes were made according to a modification of the criteria of Fajans and Conn. Prevalence of diabetes and probable diabetes was considerably higher among men aged 40 through 49 than among those aged 30 through 39, but it increased little in the 50-through-59 and 60-through-69 age groups. Lean nondiabetics and probable diabetics had similar mean systolic blood pressures and similar mean levels of serum cholesterol, serum triglycerides, and serum insulin, but fat probable diabetics had much higher mean serum lipid and serum insulin concentrations that fat nondiabetics. Adiposity grouping discriminated by variable levels less well between diabetics and nondiabetics.

Physiological variables and diabetic status. Findings in Tecumseh, Mich.

A random sample of 568 participants in the Tecumseh, Mich, study, aged 30 to 59 years, was stratified according to blood glucose concentration to select a high proportion of diabetics. Subjects were categorized as overt diabetics, chemical or probable diabetics, or nondiabetics. Diabetic groups and nondiabetics were compared for levels of blood glucose, plasma insulin, serum cholesterol, serum triglyceride, blood pressure, and contours of glucose and insulin curves. Overt diabetics had high mean fasting blood glucose levels. Challenged diabetics had significantly higher concentrations of all variables except cholesterol than nondiabetics, even after adjustment for age and adiposity. Glucose intolerance, adiposity, and sex influenced variables independently. Risk of atherosclerosis is partly attributable to persistent hyperglycemia and related metabolic abnormalities in overt diabetics. Postchallenge diabetics have subtle hyperglycemia but a high frequency of other risk factors. Recent developments suggest that control of blood glucose may become feasible and useful in the prevention of cardiovascular disease in overt and challenged diabetics.

Daily nutritional intake and serum lipid levels. The Tecumseh study.

To determine the influence of diet on serum cholesterol and triglyceride levels among adults, 24-hr dietary recall interviews were conducted among 957 men and 1,082 women resident in the community of Tecumseh, Michigan. Trained interviewers obtained detailed description of all foods consumed during 24 hr before venipuncture for lipid determination. Using a list of nutritional composition of 2,706 foods prepared from standard references, nutritionists determined quantities of all nutrients common to the American diet which were consumed by each participant according to a 24-hr diet record. For analysis, men and women were grouped into lower middle, and upper tertiles according to serum cholesterol and triglyceride levels. The mean daily consumption of each dietary component was virtually identical in all tertiles for men and women but differed between sexes. Cholesterol and triglyceride levels were unrelated to quality, quantity, or proportions of fat, carbohydrate, or protein consumed in the 24-hr recall period.

Epidemiological study of the electrocardiographic diagnosis of left ventricular hypertrophy.

Electrocardiograms from 5,129 examined persons, 2,449 men and 2,680 women, 16 years of age or older, were classified according to the Minnesota code of Blackburn and associates. The R wave amplitude criteria for possible left ventricular hypertrophy were fulfilled in 193 tracings from 135 men and 58 women. Age and sex matched controls were randomly selected from the remainder of the examined population for similar measurement. Those with high amplitude R waves and their controls were grouped according to age, sex, and possible cause for anatomical left ventricular enlargement. Precise measurements were made of all the amplitudes and intervals necessary for the application of a variety of other differential items from current diagnostic criteria. The prevalence of the various differential items in the high amplitude and control groups and the frequency with which each was associated with a cause for enlargement indicated their relative sensitivity and specificity. Among the individuals with electrocardiographic evidence of left ventricular hypertrophy according to the Minnesota criteria, there were more persons in the upper and lower quintiles of the relative weight distributions, more hypertensives, more persons with roentgenographic evidence of cardiomegaly, and fewer persons in congestive heart failure than among the controls, but the differences were slight. Most QRS amplitude items were too nonspecific to be of much diagnostic value among young men, and the same items apparently lack sensitivity when applied to the tracings from older women. The items which constitute the Minnesota criteria are useful for screening purposes. Single items are unreliable for the detection of left ventricular hypertrophy and certain combinations are suggested to improve diagnostic accuracy. Still the electrocardiogram is often an inexact method for the recognition of left ventricular hypertrophy and the diagnosis should be based on careful physical and roentgenographic examinations as well.

Coronary risk factors in a community. Findings in Tecumseh, Michigan.

In the Tecumseh study population examined from 1967 through 1969, 1457 men and 1607 women were separated into young (20-39 years), middle (40-54 years), and old (past 55 years) age categories. A subset of the study population, 183 men and 200 women who were repeatedly hyperglycemic according to a modified glucose tolerance test, were divided into the same age groups. Means and standard deviations of adiposity index, serum cholesterol, serum triglyceride, blood glucose, and systolic blood pressure were calculated for the total population and hyperglycemics. Correlation coefficients were determined for the relationship between adiposity index and each of the other variables and between paired variables exclusive adiposity index. Correlation coefficients for the latter relationships were recalculated after adjustment for the effect of adiposity. Means of variables were higher in middle and older age categories than in young age categories in both sexes, but the greatest incremental increases occurred between the young and middle-aged groups of men and between middle and old age groups among women. Men had significantly higher mean triglyceride and systolic blood pressure values than women in young and middle ages. Except for the cholesterol-triglyceride association, lipids, glucose, and systolic blood pressure were more highly correlated with adiposity than with each other. Correlations between variables were reduced by adjustment for adiposity. Hyperglycemics had higher mean adiposity indexes, serum lipids, and systolic blood pressures and generally higher correlations of variables than the entire study population. Much of the interrelationship of variables among hyperglycemics was associated with adiposity. Among men, higher mean triglyceride and systolic blood pressure levels, more frequent coexistence of risk factors, and a tendency to have large incremental increases in mean variables between young and middle age probably contribute to greater male susceptibility to ischemic heart disease. Levels of variables in the population and aggregation of coronary precursors in individuals are related to adiposity and hyperglycemia.

Detection of individual susceptibility toward coronary disease.

Current views on the usefulness of pre-clinical markers to detect susceptibility toward coronary heart disease have been presented, including the role of the hyperlipidemias, hypertension, hyperglycemia, obesity, family history and several other personal attributes. In addition, various clinical, electrocardiographic and other indices of early clinical disease serve as premonitory warning signals toward myocardial infarction and sudden death. Individuals harboring one or more of these risk factors should be detected and protected by means of preventive measures.

Blood glucose and risk of coronary heart disease.

Health status of 1877 Tecumseh Study subjects aged 35-64 years was ascertained in 1977. They represented 77% of the persons in this age range who were apparently healthy and had participated in comprehensive examinations of nearly the entire population of the community in 1959-1960 and 1962-1965. Subjects who developed coronary heart disease had a significantly higher mean blood glucose concentration than other members of the cohort, even after exclusion of diabetics. Similarly, when examined as single variables, age, sex, serum cholesterol, systolic blood pressure, number of cigarettes smoked per day, and relative weight were significantly related to incidence of coronary events. In the multiple logistic function, however, age, cigarette smoking, blood pressure, and blood glucose were the only significant variables. In a two-way interaction model, glucose and cholesterol were a highly predictive pair. After exclusion of diagnosed diabetics, glucose by itself or in interaction with other variables was not significant in the multiple logistic functions.

Diabetes mellitus in Tecumseh, Michigan. Prevalence, incidence, and associated conditions.

A high proportion of the population of Tecumseh, Michigan, participated in comprehensive assessments of health, personal habits, and socioeconomic status during the periods 1959-1960 and 1962-1965. A total of 5735 persons older than 20 years of age, comprising 2749 men and 2986 women, form the subject of this report. Diabetics were identified at entry and contrasted to nondiabetics with respect to personal characteristics. During the period 1977-1979, health status of 69% of the eligible cohort was ascertained. Age, adiposity, and blood glucose level were the principal predictor of new cases of diabetes. Family history was a significant predictor only among middle-aged, overweight men. Diabetes tended to be related to central fat distribution as indicated by subscapular skinfold thickness. Predictors of new cases of diabetes were not necessarily related to prevalence of the disease in this population.

Mortality from coronary heart disease in the Tecumseh study. Long-term effect of diabetes mellitus, glucose tolerance and other risk factors.

The coronary heart disease mortality of participants in the Tecumseh study was examined with particular emphasis on the roles of diabetes and glucose tolerance as risk factors. The cohort consisted of 921 men and 937 women aged 40 years and older who did not have evident coronary heart disease at entry to the study during the period 1959-1965 and whose outcome was determined in the period 1977-1979. Previously diagnosed diabetes was a statistically significant risk factor for coronary heart disease mortality in both sexes even after controlling for systolic blood pressure, serum cholesterol, relative weight, and cigarette smoking. High blood glucose score in nondiabetics was associated with excess coronary heart disease mortality after controlling for other risk factors, but the magnitude of this effect was substantially below that of diabetes. The predictive power of most risk factors except age itself decreased among progressively older segments of the population.