PubMed HealthSearch

Biomedical subjects

M Feinleib

Publications and source records attributed to M Feinleib.

At least 19 recordsLinked to original sources

Increased mortality from brain tumors: a combined outcome of diagnostic technology and change of attitude toward the elderly.

United States national data were used to assess factors responsible for the increase of brain tumor mortality. Between 1968 and 1988, death rates increased 50% among those aged 65-74 years, 200% among those aged 75-84 years, and 800% in the oldest old. Rate of increase and maximum death rate have changed over time. Death rate among the population aged 65-74 years peaked in the mid-1980s, while among those aged 85 years and older it is projected to continue increasing throughout the 1990s. The patterns of rate increases were almost identical in the two sexes, as well as among whites and nonwhites. There was a strong correlation over time of death rates with head diagnostic procedures (r = 0.96) and with the pace of computerized axial tomography installation (r = 0.91). The authors conclude that the reported increase in brain tumor mortality is not genuine, but represents a combination of three factors: availability of more sophisticated, noninvasive diagnostic technology; change in the attitude toward care of the elderly; and introduction of support programs such as Medicare that facilitate diagnostic procedures in the elderly.

Age Factors

The epidemiologist's responsibilities to study participants.

Epidemiologists and health survey statisticians must be aware of their many responsibilities to study participants during all phases of the investigation. Safeguards for the subject's welfare and privacy must be considered during the planning of the study, recruitment of participants, conducting the interviews or examinations, maintaining the records, and analyzing and disseminating the information. In order to achieve maximum participation and candor of study respondents, the importance and purposes of the study and the safeguards for protecting the respondents' privacy and minimizing risks must be clearly explained. All staff must be carefully trained as to their responsibilities for protecting the privacy and safety for the participants. Adherence to these principles will promote the collection and dissemination of quality data while minimizing the risks and burdens to study participants.

Confidentiality

The relation of antemortem characteristics to cardiovascular findings at necropsy--The Framingham Study.

The relation of premorbid cardiovascular risk attributes routinely measures at regular biennial examinations to cardiac necropsy findings using a special autopsy protocol was examined among 127 decedents of the Framingham cohort. Necropsy findings analyzed were: heart weight, left ventricular (LV) muscle thickness, percent luminal insufficiency of the coronary arteries, and percent intimal involvement with atherosclerosis. Clinical data analyzed included weight, height, blood pressure and serum cholesterol measured 1, 5, and 9 years prior to death. Systolic blood pressure, but not diastolic, correlated strongly with heart weight and LV muscle thickness in both sexes, and with atherosclerotic involvement in women, but not men. Serum cholesterol 1, 5, and 9 years antemortem all correlated positively with the degree of luminal insufficiency in men, while in women only cholesterol 9 years before death correlated significantly. In multivariate analysis only systolic pressure in women correlated independently with left ventricular muscle thickness and relative weight was the only independent correlate of heart weight. Only age was an independent significant correlate of the extent of coronary atherosclerosis in women. For men, coronary atherosclerotic involvement was independently correlated with only the serum cholesterol and measures of obesity were the major predictors of heart size. The degree of coronary pathology also correlated positively with heart weight in men and LV muscle thickness in women. In general clinical data measured just prior to death did not correlate as well with pathological findings as did earlier measurements.

Adult

Detection of genetic variance in blood pressure of seven-year-old twins.

Results from twin studies in older children and adults indicate that there is significant genetic variance for blood pressure (BP). Utilizing date which were collected in 12 US university-affiliated hospitals in 1966-1973 in the Collaborative Perinatal Project (NCPP), the authors sought to determine if the effects of heredity on BP variability are apparent in younger twins. BP was determined in 197 pairs of like-sexed twins at seven years of age. Significant genetic variability for diastolic blood pressure (DBP) was found in the twins, with a heritability estimate of 0.53. Systolic blood pressure (SBP) results tended in the same direction but were not statistically significant. The trends were comparable for both sexes and races. These findings suggest that even at a young age substantial genetic influences on DBP variability are detectable.

Blood Pressure

An investigation of coronary heart disease in families. The Framingham offspring study.

The Framingham Heart Study (FHS) was started in 1948 as a prospective investigation of cardiovascular disease in a cohort of adult men and women. Continuous surveillance of this sample of 5209 subjects has been maintained through biennial physical examinations. In 1971 examinations were begun on the children of the FHS cohort. This study, called the Framingham Offspring Study (FOS), was undertaken to expand upon knowledge of cardiovascular disease, particularly in the area of familial clustering of the disease and its risk factors. This report reviews the sampling design of the FHS and describes the nature of the FOS sample. The FOS families appear to be of typical size and age structure for families with parents born in the late 19th or early 20th century. In addition, there is little evidence that coronary heart disease (CHD) experience and CHD risk factors differ in parents of those who volunteered for this study and the parents of those who did not volunteer.

Adult

A comparison of blood pressure, total cholesterol and cigarette smoking in parents in 1950 and their children in 1970.

Blood pressure and serum cholesterol levels as well as cigarette smoking are compared for parents who were examined in the Framingham Heart Study between 1948 and 1950 and their offspring who were studied in the early 1970s in the Framingham Offspring Study. For ages 30-49 years there are modest but significant differences in both systolic and diastolic blood pressure when mothers are compared to daughters, with the average pressures in the daughters being lower. Blood pressure differences in fathers and sons are not as large, and they disappear when families which include hypertensives are eliminated from the analysis. Total cholesterol levels were found to be significantly lower in both daughters and sons, but the difference was not large after adjusting for changes in methodology. The proportion of cigarette smokers was found to be substantially lower in the sons in all age groups, and modest reductions in cigarette smoking were also noted in all but the oldest (age 45--49 years) group of daughters.

Adult

The association of total cholesterol, triglycerides and plasma lipoprotein cholesterol levels in first degree relatives and spouse pairs.

HDL, VLDL, and LDL cholesterol as well as total cholesterol were measured in young adult offspring of Framingham Heart Study participants. Parental total cholesterol levels measured in the early 1950s were found to be significant predictors of present total cholesterol in the offspring. While both maternal and paternal cholesterol levels made an independent contribution to the prediction of the offspring's cholesterol, the mother's contribution was significantly greater than the father's for male offspring with a similar but less striking relationship for female offspring. The correlation for LDL cholesterol levels for siblings was higher than for HDL cholesterol or log VLDL choles terol. When adjustments were made for age, body weight, alcohol intake and cigarette smoking, slight reductions in the correlations were noted, but all adjusted correlations remained significantly different from zero. The spouse correlations for lipoproteins, however, did not differ from zero after adujustment. Since the significant association for lipoproteins in spouse pairs disappears on adjustment for correlates but the association for siblings does not, it is likely that the sibling lipoprotein associations result from either genetic or environmental factors shared early in life.

Adult

alpha1-Antitrypsin deficiency in twins and parents-of-twins.

Serum-trypsin-inhibitory-capacity (STIC) and alpha1-antitrypsin (AAT) genotypes were evaluated in 83 twins and 112 paired parents-of-twins. An increased prevalence (17.0--21.9%) of intermediate AAT deficiency (STIC less than 0.95 units/ml) was detected in both of these groups as compared to a prevalence of 4.1% in 1,841 healthy controls. PiS and PiZ molecular variants of AAT were also found more frequently in the twin and parent groups, but this was not statistically significant. Low levels of protease inhibition may enhance fertility and a tendency towards twinning, since proteolytic enzymes are involved in fertilization of ova by sperm and in gametogenesis. Increased fertility and twinning may be heterozygous advantages for AAT deficiency.

Female

A twin analysis of dietary intake: evidence for a need to control for possible environmental differences in MZ and DZ twins.

In the NHLI Twin Study MZ twins are shown to "get together" substantially more often than DZ twins. With this result as an indicator of differences in shared environment, the assumption of equal shared environmental variation for MZ and DZ twins is assessed using nutritional data calculated from a food frequency questionnaire. Six nutrients show significant genetic variance for the total sample. However, when stratified on the basis of how frequently twins see each other, none of the nutrients shows significant genetic variance for both strata. A similar pattern is seen for several individual items from the questionnaire. In addition, four of the nutrients show significant correlation between the absolute difference in the nutrient intake of MZ twin pairs and how often they "get together." These data appear to show that unequal environmental effects may lead to falsely high estimates of genetic variance for nutrient intake.

Adult

Cigarette smoking and HDL cholesterol: the Framingham offspring study.

High density lipoproteins were measured on fasting blood samples from 4107 men and women. Control for reported alcohol consumption and subscapular skinfold thickness using multiple regression analysis allowed an examination of the relationship between cigarette smoking and HDL cholesterol. Cigarette smoking was found to be associated with an average difference in HDL cholesterol of about 4 mg/dl in men and 6 mg/dl in women. Furthermore, when heavy alcohol drinkers were eliminated a significant negative association between number of cigarettes smoked and HDL cholesterol was demonstrable in both men and women. There was no evidence that former cigarette smokers, with the exception of those who switched to cigars or pipes or had quit less than one year, had lower HDL levels. Cigar or pipe smokers who had never smoked cigarettes had alcohol- and skinfold-adjusted HDL cholesterol comparable to the non-smoker. These observations indicate another possible link between inhaled tobacco smoke and the atherosclerotic process and suggest the need for further studies and experiments that might clarify the mutual relationship of HDL cholesterol, cigarette smoking and the atherosclerotic process.

Adult