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L H Kuller

Publications and source records attributed to L H Kuller.

At least 325 records · Page 18Linked to original sources
PubMed1991

Research and policy directions. Salt and blood pressure.

The relation between dietary intake of sodium chloride and blood pressure levels remains controversial. The critical questions concern whether there is a susceptible subgroup at risk of elevated blood pressure because of sodium chloride consumption. If there is such a subgroup, what is its size and how can it be identified? Further clinical trials are needed to determine the long-term effects of sodium chloride reduction on blood pressure. The risk of disease, including stroke and coronary heart disease, is linear with blood pressure levels. A small change in blood pressure can have a relatively large impact on disease, even within the normal range of blood pressure.

Biological Evolution↗
PubMed1991

The interface between epidemiology and molecular biology in the search for the causes of insulin-dependent diabetes mellitus.

Epidemiological techniques have been utilized to accumulate new knowledge about insulin-dependent diabetes mellitus (IDDM), leading to important insights into the disease process and the alteration of these mechanisms when viewed from a geographic or population base. More recently, highly powerful and sophisticated techniques of molecular biology have been added to the research arsenal, extending the knowledge on the genetic basis for IDDM and the probable environmental factors involved. The development and growth of the new discipline of epidemiological genetics promises exciting new developments for the future of our field as well as that of other major medical problems having a genetic base, but significantly influenced by environmental factors. This review stresses the importance of carefully validated diabetes registries in the study of the epidemiology of IDDM. The Children's Hospital of Pittsburgh and the University of Pittsburgh Medical Center have spear-headed the development of such registries, worldwide. The first international meeting on IDDM epidemiology in 1983 gave as a result, i.e., the finding that there were truly remarkable differences in the risk of developing IDDM depending upon the geographic location of the individual. Later collaborative work via the Diabetes Epidemiology Research International (DERI) group has confirmed the previous finding and added the description of secular trends and epidemics of IDDM. It is remarkable that the incidence rate of IDDM in children below 15 years vary from 1/100,000/yr in the Orient to 35/100,000/yr in Finland. The epidemiological approach in the study of IDDM has also stimulated research into the various facets of the etiology of the disease, genetic factors, autoimmune mechanisms and environmental factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗
PubMed1991

Cross-sectional and longitudinal relationship of sodium-lithium countertransport to insulin, obesity and blood pressure in healthy perimenopausal women.

The objectives of this study were to assess the possible role of insulin as a regulator of red blood cell sodium-lithium countertransport and to examine the relationship of countertransport activity to change over time in insulin, blood pressure, and other variables. At baseline, countertransport was measured, and at baseline and after 2-3 years of follow-up, blood pressure, body mass index (BMI), lipids, fasting and two-hour plasma insulin and glucose were measured in 144 white healthy, premenopausal women, age 42-50 years. At baseline, using high and low categories of fasting insulin, triglycerides and BMI, countertransport was independently related to fasting insulin (P = 0.017), and triglycerides (P = 0.001), but not to BMI by analysis of variance. In similar analyses with fasting insulin, BMI, and countertransport, diastolic blood pressure was independently related only to countertransport (P = 0.003). Among the 73 who remained premenopausal after 2-3 year follow-up, baseline countertransport was significantly correlated with increases in fasting and two-hour insulin (r = 0.37, 0.38, P = 0.003, respectively), and these relationships remained significant after adjustment for change in BMI. Among subjects with high baseline countertransport, systolic blood pressure increased 5.6 mmHg compared with -2.2 mmHg with low countertransport, P = 0.001 after adjusting for baseline and change in BMI, triglycerides, and fasting and two-hour insulin. The data are consistent with a role for insulin and lipids in the regulation of sodium transport which may, in turn, play a role in blood pressure regulation. A relatively short follow-up in this healthy population suggests a relationship of baseline countertransport to changes in insulin metabolism, and blood pressure.

Adult↗
PubMed1991

The relationship of Papanicolaou testing and contacts with the medical care system to stage at diagnosis of cervical cancer.

The relationship of Papanicolaou (Pap) testing and physician visits to stage at diagnosis of cervical cancer was assessed by interviews with 149 women with invasive cervical cancer and 214 women with in situ cervical cancer. A significantly smaller percent of study subjects with invasive disease than in situ disease had at least one Pap test in the 3 years prior to diagnosis (age- and race-adjusted odds ratio: 3.38). The two groups did not differ in visits to a physician for other reasons during this period. Pap testing decreased with increasing age for both groups, but not physician visits. While 65% percent of the subjects with invasive disease aged between 65 and 79 years had never had a Pap test until diagnosis, 88% had seen a physician in the preceding 3 years. Women with regional or distant invasive disease were least likely to have had Pap tests, and, within this group, those aged between 35 and 64 years were also least likely to have seen a physician. Strategies for early detection must reflect missed opportunities and the need to bring those not receiving care into the system.

Adult↗
PubMed1991

Weight gain at the time of menopause.

We studied prospectively the weight change and the effect of weight change on changes in coronary heart disease risk factors in a population-based sample of 485 middle-aged women. All women were studied first in 1983 to 1984, when they were premenopausal and aged 42 to 50 years, and then restudied in 1987. Women gained an average of 2.25 +/- 4.19 kg during this 3-year period; 20% of women gained 4.5 kg or more, and only 3% lost 4.5 kg or more. There were no significant differences in weight gain of women who remained premenopausal and those who had a natural menopause (+2.07 kg vs +1.35 kg). Weight gain was significantly associated with increases in blood pressure and levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and fasting insulin. Weight gain is thus a common occurrence for women at the time of menopause and is related to the changes in coronary heart disease risk factors observed during this period. Efforts to lose weight or to prevent weight gain may help to mitigate the worsening in coronary heart disease risk factors in middle-aged women.

Adult↗
PubMed1990

Evolution of the Pittsburgh studies of the epidemiology of insulin-dependent diabetes mellitus. Pittsburgh Diabetes Epidemiology and Etiology Research Group.

The Pittsburgh project evaluating the epidemiology and etiology of insulin-dependent diabetes mellitus (IDDM) is currently one of the large ongoing studies of childhood diabetes. This paper traces the evolution of the project, from the initial basic epidemiologic approach in the early 1980s, to the current thrust where complex molecular genetic approaches are being incorporated into population-based research. The epidemiology models employed in the Pittsburgh project are similar to those that could be used in many areas of chronic disease research. The integration of immunogenetics into epidemiology produces a powerful approach for understanding the complex interaction of host susceptibility and environmental agents that contribute to the development of IDDM.

Adolescent↗
PubMed1990

Blood pressure and other cardiovascular disease risk factors in black adults with sickle cell trait or glucose-6-phosphate dehydrogenase deficiency.

In this study, we examined the relationship of two common genetic markers in black populations, sickle cell trait and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, to cardiovascular risk factors. The subjects were Nigerian civil servants in Benin City, Nigeria. We measured blood pressure, height, weight, sickle cell hemoglobin, G-6-PD, proteinuria, microalbuminuria and fasting serum cholesterol, high-density lipoprotein cholesterol (HDL), triglycerides, apoprotein (APO) AI, and APO B. Data were collected on age, alcohol consumption, cigarette smoking, job status, and years lived in an urban area. There were 257 males (3 SS hemoglobin, 73 AS, 181 AA) and 69 females (23 AS, 46 AA). In comparing cardiovascular risk factors, males differed only in percent of smokers (31.5 in AS vs. 17.8 in AA, P less than 0.01). Among females, only high-density lipoprotein (HDL) cholesterol differed (61.5 mg/dl in AS vs. 52.4 in AA, P less than 0.01). We hypothesize that females with sickle cell trait are more likely to use oral contraceptives than nontrait females. If so, the high-estrogen oral contraceptives available in Nigeria could elevate HDL. G-6-PD deficiency status among males (52 deficient, 207 nondeficient) and females (1 deficient, 5 carriers, 65 nondeficient) was not related to any of the cardiovascular risk factors. We conclude that sickle cell hemoglobin trait and G-6-PD deficiency are not useful genetic markers for risk factors for cardiovascular disease.

Albuminuria↗
PubMed1990

Alpha 2-HS glycoprotein phenotypes and quantitative hormone and bone measures in postmenopausal women.

It has been suggested that inherited traits play a role in the development of osteoporosis by providing a background for the modulation of gene expression. In this study, we examine the influence of the different alleles of alpha 2-HS glycoprotein (AHSG), a protein of the bone matrix, on quantitative estrogens, estrone and estradiol, and bone measures, bone area and density. Estrogens provide a protective effect against fractures in older women and were thus included in the analyses. Isoelectric focusing of AHSG from sera followed by immunoblotting was used to type 163 white postmenopausal women participating in a clinical trial of the effects of walking on bone loss. Plasma hormones were measured by a combination of extraction, column chromatography, and radioimmunoassay; bone measures on the dominant radius were determined with computerized tomography. Analysis of variance was done on estrogen and bone measures after controlling for the effects of age and body mass index. The two major alleles of AHSG result in three phenotypes, designated AHSG 1-1, AHSG 2-1, and AHSG 2-2. The AHSG 1-1 homozygote showed a decreased concentration of estradiol, the AHSG 2-2 homozygote showed an increased concentration, and the AHSG 2-1 heterozygote was intermediate (P = 0.001). Estrone demonstrated a similar pattern in residual analysis although it did not reach statistical significance.

Aged↗
PubMed1990

Physical activity and cardiovascular risk: a cross-sectional study of middle-aged premenopausal women.

The relationship between self-reported physical activity and cardiovascular risk factors was evaluated in a population-based sample. The sample included 541 premenopausal women recruited for a study of the natural history of risk factor change associated with change in sex hormone status. Physical activity was assessed using the Paffenbarger Activity Questionnaire. Women were classified according to quartile of weekly energy expenditure into groups of 0-500, 501-999, 1,000-1,999, and 2,000 kcal or greater. Results showed that the more active the women, the lower their blood pressure and heart rate. More active women had lower cholesterol and triglycerides, and higher high-density lipoprotein (HDL) cholesterol. Tricep and suprailiac skinfolds, fasting insulin, and insulin/glucose levels were also lower among the more active women. When the analysis was repeated controlling for the effect of education and body mass index, the statistical test for linear trend remained significant except for the trend for heart rate, total cholesterol, and triglycerides. Women reporting activity of 1,000 kcal/week had higher high-density lipoprotein cholesterol and lower diastolic blood pressure, body mass index, skinfolds, fasting insulin, and fasting insulin/glucose ratios compared with women reporting lower levels of activity. Only those women who reported 2,000 kcal/week had significantly lower total cholesterol, triglycerides, and low-density lipoprotein cholesterol, and higher HDL2 cholesterol; women reporting less activity did not differ with regard to these lipids and lipoproteins. The study suggests that physical activity is associated with improved cardiovascular risk profiles among middle-aged women and that the beneficial effects of activity are seen at different levels for specific risk factors.

Adult↗
PubMed1990

Validation of reported myocardial infarction mortality in blacks and whites. A report from the Community Cardiovascular Surveillance Program.

It is widely believed that blacks experience a higher mortality due to coronary heart disease (CHD) than do whites. To determine whether this reported difference in mortality between blacks and whites is real, we studied the question in the context of the Community Cardiovascular Surveillance Program (CCSP). Fatal and nonfatal cases of CHD were reviewed in 12 US communities. Standardized criteria were applied to classify these cases as possible CHD, definite CHD, possible myocardial infarction (MI), or definite MI. The annual age-adjusted mortality rate per 100,000 ascribed to definite MI by the CCSP criteria was higher in blacks than in whites: 47 in white men (95% confidence interval, 36 to 58), 18 in white women (95% confidence interval, 8 to 28), 95 in black men (95% confidence interval, 10 to 180), and 41 for black women (95% confidence interval, 0 to 99). The proportion of definite MI to all fatal CHD events was higher in blacks (16%) than in whites (12%). For nonfatal events, however, the rate of definite MI was higher in whites than in blacks: 322 in white men (95% confidence interval, 293 to 351), 225 in black men (95% confidence interval, 160 to 290), 82 in black women (95% confidence interval, 43 to 121), and 103 in white women (95% confidence interval, 88 to 118). The proportion of definite MI to all nonfatal CHD events was lower in blacks (16%) than in whites (30%). Thus, the overall rate for fatal and nonfatal definite MI was lower in blacks (215/100,000) than in whites (244/100,000). These observations suggest that a combination of high case-fatality ratio and misclassification of cause and death may contribute to the reported higher rate of CHD mortality among blacks.

Adult↗
PubMed1990

Influences of natural menopause on psychological characteristics and symptoms of middle-aged healthy women.

We investigated the psychological and symptom consequences of the natural menopause in a longitudinal study of 541 initially premenopausal healthy women. All women were given an extensive evaluation at baseline. After 3 years of follow-up, 69 women ceased cycling for 12 months; another 32 women had ceased cycling and had taken hormone replacement therapy for a total of 12 months. These women were reevaluated in a clinic examination identical with the baseline examination, as were 101 age-matched premenopausal control women. Comparison among groups at the baseline and follow-up examination showed that natural menopause led to few changes in psychological characteristics, with only a decline in introspectiveness and an increase in reports of hot flashes being apparent. We conclude that natural menopause did not have negative mental health consequences for the majority of middle-aged healthy women.

Adaptation, Psychological↗
PubMed1990

Relation of forced expiratory volume in one second (FEV1) to lung cancer mortality in the Multiple Risk Factor Intervention Trial (MRFIT).

For men participating in the Multiple Risk Factor Intervention Trial, the authors evaluated the relation between the baseline forced expiratory volume in one second and lung cancer mortality among smokers between the third and tenth years of follow-up (1973-1974 to 1984). This measure of ventilatory function was a powerful predictor of lung cancer deaths, with rates that increased from 3.02 per 1,000 person-years in the lowest quintile of forced expiratory volume to 0.43 in the highest quintile. This relation was not weakened by adjustments for smoking dose, including number of cigarettes smoked per day, tar and nicotine content, duration of smoking, or age at onset of smoking. Nor was forced expiratory volume related to time between its determination and lung cancer death. If these observations can be verified in other studies, the forced expiratory volume in one second may identify smokers at very high risk of lung cancer and, hence, in need of more aggressive preventive approaches.

Adult↗
PubMed1990

The relation of endogenous sex steroid hormone concentrations to serum lipid and lipoprotein levels in postmenopausal women.

The relation of concentrations of endogenous estrogens and androgens to lipid and lipoprotein levels was examined in 176 white, postmenopausal women (mean age, 58 years) with an average of 9 years since the onset of menopause. All of the women were participants in a clinical trial of the effect of walking on postmenopausal bone loss. In that trial, women were randomized into either a walking group or a control group and were followed for 3 years. There were no differences in the serum hormones or lipids by randomized group, and hence, results from this study are presented for both groups combined. None of the women were on estrogen replacement therapy. Data were available from year 1 (1982-1983) of the trial for the estrogens, lipids, and lipoproteins. Information on androgens was available for 143 of these women. Hormone levels were determined by highly specific methods involving extraction, column chromatography, and radioimmunoassay. About 50% of the women had estradiol levels at or below the sensitivity level (2.5 pg/ml) of the assay; therefore, estradiol levels were viewed as dichotomous (measurable/not measurable), and the estradiol results should be interpreted with caution. There was little relation of the androgens to the lipid values. Univariate analyses suggested a direct relation between total cholesterol, low density lipoprotein cholesterol, and triglyceride levels with estradiol. An inverse relation was suggested between serum estrone and estradiol and total high density lipoprotein (HDL) cholesterol and HDL2 cholesterol, although none of these associations were statistically significant. Multiple regression analyses revealed that the primary determinant of the HDL cholesterol and triglyceride levels was the degree of obesity as estimated by the body mass index (weight (kg)/height (m)2). Addition of estrone or estradiol to the models did not contribute to the prediction of lipid levels. These results do not support the hypothesis of there being a relation between endogenous sex hormone levels and lipid levels in postmenopausal women. The results suggest that sex hormones cannot explain the sex difference in lipid levels and may not contribute to the rise in coronary heart disease that occurs in women around menopause.

Androstenedione↗
PubMed1990

Hormone replacement therapy and lipoprotein changes during early menopause.

The relationship of postmenopausal hormone replacement therapy to lipoproteins was assessed in a cohort of 211 healthy premenopausal women followed during the menopausal transition. Both estrogen and estrogen-progestogen users had minimal increases in low-density lipoprotein (LDL) cholesterol levels, whereas non-users had significant increases in LDL cholesterol over time. Estrogen users had a nonsignificant increase in high-density lipoprotein (HDL) cholesterol, estrogen-progestogen users maintained premenopausal HDL cholesterol levels, and non-users had decreases in HDL cholesterol. Both estrogen and estrogen-progestogen users had increases in apolipoprotein AI, apolipoprotein AII, and triglycerides relative to the changes observed among the menopausal non-users. In summary, estrogen, whether administered with or without medroxyprogesterone acetate, could provide cardiovascular benefits to postmenopausal women by protecting against the atherogenic changes in LDL and HDL cholesterol observed among the non-users. With the exception of the hormone-related increases in triglycerides, the results are consistent with a beneficial effect of hormone replacement therapy on coronary heart disease risk.

Adult↗
PubMed1990

Insulin-dependent diabetes mellitus mortality. The risk of cigarette smoking.

The relation between cigarette smoking and mortality was examined prospectively in a population of adult insulin-dependent diabetes mellitus (IDDM) patients. In 1981, information on smoking history and other health and lifestyle factors was obtained by questionnaire from 93% of the 723 patients included in the Children's Hospital of Pittsburgh IDDM registry who were diagnosed between 1950 and 1964. Vital status as of January 1, 1988 was ascertained for 98% of the 548 patients who participated in the baseline survey and were alive as of January 1, 1982. Fifty-four cases died during the 6-year follow-up (32 male, 22 female). Proportional hazards analysis revealed that heavy smoking was a significant independent predictor of all-cause mortality among females but not males. The excess mortality in female diabetics was explained primarily by a marked excess risk of coronary heart disease mortality in smokers. These data strongly suggest that cigarette smoking, especially among diabetic females, should be avoided in order to improve longevity.

Cause of Death↗
PubMed1990

The relationship of smoking cessation to coronary heart disease and lung cancer in the Multiple Risk Factor Intervention Trial (MRFIT).

The impact of smoking cessation on coronary heart disease (CHD) and lung cancer was assessed after 10.5 years of follow-up in the 12,866 men in the Multiple Risk Factor Intervention Trial (MRFIT). Those men who died of lung cancer (n = 119) were either cigarette smokers at entry or ex-smokers; no lung cancer deaths occurred among the 1,859 men who reported never smoking cigarettes. The risk of lung cancer for smokers, adjusted for selected baseline variables using a Cox proportional hazards model, increased as the number of cigarettes smoked increased (B = 0.0203, SE = 0.0076). There was not the same graded response for CHD among smokers at entry. The risk of CHD death was greater among smokers than nonsmokers (RR = 1.57) (B = -0.0034, S.E. = 0.0048). After one year of cessation, the relative risk of dying of CHD for the quitters as compared to non-quitters (RR = 0.63) was significantly lower even after adjusting for baseline differences and changes in other risk factors. The relative risk for smokers who quit for at least the first three years of the trial was even lower compared to non-quitters (RR = 0.38). However, the relative risk for lung cancer for quitters versus non-quitters was close to 1 both for quitters at 12 months and at three years. These data support the benefits of cessation in relation to CHD and are consistent with other epidemiologic studies which suggest that the lag time for a beneficial effect of smoking cessation on lung cancer may be as long as 20 years.

Adult↗