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T Byers

Publications and source records attributed to T Byers.

At least 73 records · Page 4Linked to original sources
PubMed1995

Parental age and breast cancer mortality.

Because older ages of both mothers and fathers have been hypothesized by others to increase the subsequent risk of breast cancer in female babies, we analyzed the association between maternal and paternal age at birth and mortality from breast cancer in a cohort of 384,796 American women. Cox proportional hazards modeling accounted for age, family history of breast cancer in first-degree relatives, age at menarche, age at first pregnancy, and parity. We found little association between paternal age at birth and death from breast cancer. Although there was no clear linear trend for higher risk with increasing age of the mothers at birth, women born to mothers age 45 years or older had a relative hazard of 1.30 (95% confidence interval = 0.85-1.98), compared with women born to mothers under the age of 20 years. Although these findings are of little public health significance, they may indicate a hormonal profile in older mothers that predisposes female offspring to a higher risk of breast cancer in later years.

Adult↗
PubMed1995

Alcohol intake and subsequent mortality: findings from the NHANES I Follow-up Study.

OBJECTIVE: Because past research has focused primarily on populations of middle-aged men, the relationship between alcohol and mortality among women and the elderly has been less well substantiated METHOD: We examined the relationship between alcohol intake and mortality using data from the NHANES I Epidemiologic Follow-Up Study. Total mortality was examined for both sexes (N = 4,614 women, 3,573 men), but ischemic heart disease (IHD) mortality was examined only for men because the number of deaths was too small in women. Proportional hazards modeling was used to adjust for the baseline characteristics of age, race, education, body weight, smoking and physical activity. RESULTS: For men aged 40 to 64, the adjusted relative risks (RR) of death for drinking levels of .5 drinks/day, .5 to < 2 and > or = 2 (compared to the nondrinking reference group) were 0.8 (95% Confidence Interval: 0.6, 1.1), 0.9 (CI:0.6, 1.2) and 1.2 (CI: 0.9, 1.6); RRs of IHD mortality were 0.6 (CI: 0.4, 0.9), 0.5 (CI: 0.3, 0.9) and 0.7 (CI: 0.5, 1.2). For women aged 40 to 64, the RRs for death for the same exposure categories were 1.2 (CI: 0.9, 1.6), 0.9 (CI: 0.6, 1.4) and 1.9 (CI: 1.2, 3.0). Among both sexes 65 years and older, consumption of < 2 drinks/day was associated with about a 20% decrease in total mortality and IHD mortality (men only). However, this protective effect disappeared after exclusion of those with pre-existing disease. CONCLUSIONS: Our findings support a protective effect of moderate alcohol intake on IHD mortality in middle-aged men. Among both men and women, there was little evidence of a protective association between moderate alcohol intake and total mortality after excluding those with pre-existing disease.

Adult↗
PubMed1995

Fruit and vegetable intake among adults in 16 states: results of a brief telephone survey.

A brief food frequency questionnaire was used to assess daily fruit and vegetable consumption among 23,699 adults in 16 US states sampled in a random-digit dialing telephone survey. Men consumed fewer servings per day (3.3) than did women (3.7). Only 20% of the population consumed the recommended 5 or more daily servings. Intakes varied somewhat by state and were lower among the young and the less educated. Efforts are needed to improve fruit and vegetable consumption among all Americans, especially younger adults and those with lower levels of education.

Adolescent↗
PubMed1995

The association between leisure-time physical activity and dietary fat in American adults.

Relations between leisure-time physical activity and dietary fat were examined in a population-based probability sample of 29,672 adults in the 1990 Behavioral Risk Factor Surveillance System. Consumption of 13 high-fat food items and participation in physical activities were measured, and fat and activity scores were calculated. Dietary fat and physical activity were strongly and inversely associated. This association was independent of nine other demographic and behavioral risk factors. Etiologic researchers should consider that diet and physical activity can potentially confound each other, and creators of public health messages that target one behavior should consider including the other.

Adolescent↗
PubMed1995

The costs and effects of a nutritional education program following work-site cholesterol screening.

OBJECTIVES: The purpose of this study was to assess the costs and impact of a nutrition education program following a cholesterol screening. METHODS: Forty work-sites were randomly assigned to one of two educational interventions: a "usual" intervention of 5 minutes of counseling, or a "special" intervention of 2 hours of behaviorally based education on dietary changes to lower serum cholesterol. Costs were monitored, and cholesterol levels were retested 6 and 12 months later. RESULTS: The total per-person cost for screening and the educational intervention was about $50. Cholesterol levels differed little between the two intervention groups 6 months after screening, but after 12 months those in the special intervention worksites showed a 6.5% drop in cholesterol, whereas those at the usual intervention worksites showed a drop of only 3.0%. Hence a 3.5% cholesterol reduction was attributable to the special intervention. CONCLUSIONS: A behaviorally based nutrition education program following cholesterol screening can have a meaningful impact on long-term cholesterol levels at a low cost. Nutrition education in work-sites may therefore be a useful way to lower the risk of heart disease in communities.

Adult↗
PubMed1995

Weight variability in a population-based sample of older women: reliability and intercorrelation of measures.

Six measures of weight variability were examined in a cohort of 29,015 postmenopausal women. Recalled weight at ages 18, 30, 40 and 50 years, current weight at baseline and at each of three biennial follow ups (approximate ages 62, 64, 66, 68 years), and recalled episodes of intentional and unintentional weight loss were used to construct (1) the coefficient of variation (CV) in body weight, (2) weight change categories (cycling, weight gain, weight loss and stable weight), (3) the root mean square error of variation (RMSE) around the slope of weight versus age, (4) the number of intentional weight loss episodes of 5 or more pounds, (5) the number of unintentional weight loss episodes of 20 or more pounds and (6) a categorical measure of intentional and unintentional weight loss episodes of > = 20 lb. The nine-month test-retest reliability correlations for the measures of lifetime history of intentional and unintentional weight loss were 0.80 and 0.62, respectively. Correlations between the different weight variability measures were positive but weak, suggesting that they reflect different aspects of weight variability. The RMSE discriminated categorically defined cyclers from weight gainers, but the CV did not. The weight change categories were more sensitive to age-related weight changes than the CV or RMSE. Studies examining the relationship between weight variability and health outcomes need to include measures that distinguish intentionality, short-term versus long term variability, and the magnitude, direction, and frequency of weight change.

Aged↗
PubMed1995

Can the Year 2000 objective for reducing overweight in the United States be reached?: a simulation study of the required changes in body weight.

AIM: The purpose of this analysis was to estimate the magnitude of weight change required in the six-year period between 1994 and the Year 2000 if Americans are to reach the Healthy People 2000 goal for reduction of overweight among those ages 20-74 to no more than 20% among all adults and no more than 30% among black women. Prevention of weight gain among the non-overweight is compared with that of weight loss among the overweight as strategies for reaching this goal. DESIGN: Data from the First National Health and Nutrition Examination Survey (NHANES I) and the Nutrition Examination Survey Epidemiologic Follow-up Study (NHEFS) were used to estimate 6-year weight change of persons aged 20 to 72 at the Year 2000. Men, white women, and black women were examined in addition to the overall population. Given a baseline prevalence of 24.7%, overweight in the year 2000 was projected for three simulated interventions: no weight gain among non-overweight persons (prevention-only), weight loss among overweight persons (weight-loss-only), and prevention-plus-weight-loss. In addition, the Year 2000 overweight prevalence was projected under different baseline prevalence scenarios of 26% and 34%. OUTCOME MEASURE: Prevalence of overweight; overweight determined by body mass index (> or = 27.3 kg/m2 for women and > or = 27.8 kg/m2 for men). RESULTS: Prevention-only was successful in reducing the overall prevalence of overweight from 24.7% to 20%. Weight-loss-only required a 5.3 kg weight loss to achieve the overall goal of 20% and 8.4 kg weight loss to achieve the goal within all three race-sex strata. Prevention-plus-weight-loss required only 3.8 kg of weight loss to achieve the goals within the three race-sex strata. Prevention-only was not successful in reducing the overall prevalence of overweight to 20% when the 26% and 34% baseline scenarios were used. Weight-loss-only required 6.3 and 11.2 kg; prevention-plus-weight-loss required 1.2 and 6.6 kg of weight loss using the 26% and 34% baselines, respectively. CONCLUSIONS: Prevention of weight gain among those who are not already overweight could achieve substantial changes in the prevalence of overweight, even in a 6-year time period. However, given the increasing trend in overweight, the Year 2000 goal for the reduction in prevalence of overweight will not be reached.

Adult↗
PubMed1995

Alcohol intake and breast cancer risk: effect of exposure from 15 years of age.

Research regarding the relationship between alcohol intake and breast cancer risk has suggested an association between the two, although the data are inconsistent regarding dose effects and susceptible populations. To clarify these issues, we investigated the association of breast cancer risk with alcohol intake at various ages in a population-based case-control study nested within a screening cohort in Sweden. Subjects were women 40-75 years old who participated in a screening program in central Sweden. Information about personal characteristics, diet, and alcohol intake was obtained by a questionnaire sent out at the invitation to the screening interview and at a supplementary interview conducted among a sample of women who did and did not develop breast cancer. Alcohol intake did not affect breast cancer risk among women under 50 years old. However, among those over 50 years of age, ever-drinking conferred a relative risk of 1.8 (95% confidence interval = 1.2-2.6). Current and former drinkers had similar increases in risk. No particular latent period of alcohol effect was identified, but drinking later in life to have a bigger effect than did drinking earlier in life.

Adolescent↗
PubMed1994

A prospective study of alcohol intake and change in body weight among US adults.

Little is known about the role of alcohol in determining change in body weight. In this paper, the authors examine the relation between alcohol intake and body weight in 7,230 US adults aged 25-74 years who participated in the First National Health and Nutrition Examination Survey (1971-1975) and who were reweighed 10 years later (1982-1984). Both cross-sectional and prospective analyses were adjusted for age, race, height, education, health status, smoking status, diet status, physical activity, and total nonalcoholic caloric intake. At baseline, women who reported at least one drink per day weighed 2.3 kg less than nondrinkers (95% confidence interval (CI) -0.4 to -4.2). Little relation was observed between body weight and alcohol intake cross-sectionally among men. Prospectively, both men and women drinkers tended to gain less weight than did nondrinkers (p = 0.006 for trend in women, p = 0.11 for trend in men). Drinkers also had more stable weight over the 10-year follow-up period. Drinkers were less likely to have major weight gain or loss (gaining or losing > or = 10 kg) than were nondrinkers. Compared with nondrinkers, for those who consumed 1-6.9 drinks per week, women had an odds ratio (OR) = 0.7 (95% CI 0.5 to 0.9) for major weight gain and an OR = 0.7 (95% CI 0.5 to 1.1) for major weight loss, while men had an OR = 1.0 (95% CI 0.6 to 1.6) for major weight gain and an OR = 0.7 (95% CI 0.5 to 1.2) for major weight loss. For those who consumed > or = 2 drinks per day, women had an OR = 0.5 (95% CI 0.3 to 1.0) for major weight gain and an OR = 0.8 (95% CI 0.4 to 1.6) for major weight loss, while men had an OR = 0.9 (95% CI 0.5 to 1.6) for major weight gain and an OR = 1.0 (95% CI 0.6 to 1.7) for major weight loss. These data suggest that alcohol intake does not increase the risk of obesity.

Adult↗
PubMed1994

Diet and breast cancer risk. Results from a population-based, case-control study in Sweden.

BACKGROUND: We describe an epidemiologic analytical study of the relationship between current diet and breast cancer risk. METHOD: The study design is a case-control analysis. Cases were recruited from a mammography screening program used within the national health care system; the control subjects were selected from subjects free of breast cancer in the same population. A total of 380 cases and 525 control subjects, frequency-matched for age, month of mammography, and county of residence, were identified. Of these, 265 cases and 432 control subjects were included in this analysis. Odds ratios for breast cancer in relation to food and nutrient intake were the main outcome measures. RESULTS: Exposure in the highest quartile of beta-carotene intake gave an odds ratio of 0.6 (95% confidence interval, 0.4 to 1.0). No increased risk was noted with high fat intake. Breast cancer risk was associated with alcohol intake only when alcohol was analyzed in quartiles: odds ratio, 1.6 (95% confidence interval, 1.0 to 2.4) for the highest quartile of intake vs the lowest. Stratified analyses showed that a high fat intake might decrease the protective effect of beta-carotene intake. Risks did not change appreciably with adjustment for total energy intake or known breast cancer risk factors. CONCLUSIONS: As in most other studies, no strong risk factors for breast cancer have been identified in the current diet. The negative association between breast cancer risk and beta-carotene intake may be supported by a plausible mechanism, but our finding concerning alcohol should be interpreted cautiously since there was no dose-response relationship and the biological mechanism for a threshold effect at very low levels of consumption is unclear.

Adult↗
PubMed1994

Nutritional risk factors for breast cancer.

The observation of large differences in breast cancer rates between countries has led to the hypothesis that excessive intake of dietary fat is an important risk factor for breast cancer in women. Case-control and prospective studies, however, generally have failed to show associations between dietary fat and breast cancer risk. There therefore is only weak evidence that modest reductions in fat intake (for instance to levels of 30% of caloric intake from fat) will reduce breast cancer risk. The possible benefits of lowering fat intake to levels substantially below 30% of calories will need to be tested in a randomized trial. In the meantime, the possible roles of micronutrient imbalances and childhood nutritional factors need to be studied better. Obesity is related to breast cancer in a complex way that suggests that a hormonal correlate of excessive body weight might affect breast cancer growth and metastasis. The potential benefit of intentional weight loss as an adjunct breast cancer treatment deserves further study. Many studies have suggested that drinking alcohol, even at modest levels, might increase breast cancer risk. Because the potential benefits of modest levels of alcohol for cardiovascular disease may outweigh the risk for breast cancer, recommendations for total alcohol abstinence may be premature for women with an average breast cancer risk. Women at unusually high risk for breast cancer who have a lower-than-average risk for cardiovascular disease, however, might make an informed decision to abstain from alcohol intake. Following current dietary advice to increase the amount of fruits, vegetables, and whole grains in the diet while reducing fats is certainly prudent for women to reduce their risk of several chronic disease, but current data points to the somber conclusion that such changes probably will have little effect on breast cancer risk.

Alcoholic Beverages↗
PubMed1994

Effect of smoking on serum nutrient concentrations in African-American women.

The relationship between current cigarette smoking and serum concentrations of vitamins C, E, and A, and of five carotenoids in human serum were examined in 91 low-income, African-American women. General linear models were used to adjust geometric mean serum concentrations of micronutrients for age, dietary and supplement intakes, total energy intake, alcohol intake, medication use, body mass index, and serum concentrations of cholesterol and triglycerides. Among smokers, serum concentrations of alpha-carotene, beta-carotene, cryptoxanthin, and lycopene averaged only 71-79% of the concentrations among nonsmokers. Mean serum concentrations of vitamins C and E and lutein/zeaxanthin were only slightly lower among smokers relative to nonsmokers, and current smokers had higher serum concentrations of vitamin A. Among current smokers, mean serum concentrations of all five carotenoids decreased with an increase in the amount smoked. The negative effect of smoking on serum concentrations of antioxidant carotenoids may pose a serious health risk in low-income populations already at higher risk for many chronic diseases.

Adult↗
PubMed1994

The relation of documented coronary artery disease to levels of total cholesterol and high-density lipoprotein cholesterol.

Recommendations for identifying persons at high risk for coronary heart disease are based primarily on levels of total and low-density lipoprotein cholesterol. We examined whether, given knowledge of these levels, information on the high-density lipoprotein cholesterol level would improve the prediction of arteriographically documented coronary artery disease among 591 men. We found that even at levels of total and low-density lipoprotein cholesterol considered desirable, high-density lipoprotein cholesterol was inversely related to disease severity. For example, among the 112 men with a total cholesterol level <180 mg per dl, the mean occlusion score (representing the overall severity of disease) was 107 among men with a high-density lipoprotein cholesterol level < or = 30 mg per dl vs a mean score of 52 among men with levels > or = 45 mg per dl. Furthermore, men with low levels of both low-density lipoprotein cholesterol (< 110 mg per dl) and high-density lipoprotein cholesterol (< or = 30 mg per dl) had as much occlusive disease as did men with high levels of both lipoprotein fractions. Given information on the ratio of high-density lipoprotein cholesterol to total cholesterol, the actual levels of the lipoprotein fractions did not improve disease prediction. Our results emphasize the importance of considering high-density lipoprotein cholesterol when assessing coronary heart disease risk.

Adult↗
PubMed1994

Weight control practices in adults: results of a multistate telephone survey.

In this study, data collected in 1989 in a random-digit dialing telephone survey of 60,590 adults in 38 states and the District of Columbia were analyzed. Approximately 38% of women and 24% of men reported that they were currently trying to lose weight. Methods reported were counting calories (24% of women, 14% of men), participating in organized weight loss programs (10%, 3%), taking special supplements (10%, 7%), taking diet pills (4%, 2%), and fasting for 24 hours or longer (5%, 5%). Among both sexes, only half of those trying to lose weight reported using the recommended method of caloric restriction combined with physical activity.

Adolescent↗
PubMed1993

Dietary trends in the United States. Relevance to cancer prevention.

BACKGROUND: Diet may be an important factor in the cause and prevention of cancer. Thus, in part to reduce cancer risk, the United States has set two dietary goals for the Year 2000: to reduce fat intake by 18% so that fat constitutes no more than 30% of caloric intake (baseline level 35%), and to double the consumption of carbohydrate and fiber-containing foods by increasing fruit and vegetable consumption to five servings per day and grains to six servings per day (baseline levels 2.5 and 3.0). How far the US population has progressed toward these goals is uncertain. METHODS: Dietary trends in the United States during the past 20 years were examined by compiling food supply data and dietary intake estimates from US adults from various national surveys and from individual studies. RESULTS: Dietary fat intake, considered in absolute terms and as the proportion of calories derived from fat, has been declining slightly during the past 20 years but probably remains near 35% of kilocalories derived from fat. Fruit and vegetable intake appears to be increasing, yet probably averages no more than 3.4 servings per day among US adults. These dietary trends may not be occurring equally in all socioeconomic levels of our society. CONCLUSIONS: There is evidence of modest improvement in the American diet during the past 20 years, with decreasing fat and increasing fruits and vegetables in the diet, but changes must occur at a faster pace if the Year 2000 dietary goals are to be met. More cost-efficient and more timely methods of dietary surveillance of target populations must be developed to support the development and evaluation of more effective dietary interventions.

Diet↗
PubMed1993

Do obese children become obese adults? A review of the literature.

BACKGROUND: Obese children may be at increased risk of becoming obese adults. To examine the relationship between obesity in childhood and obesity in adulthood, we reviewed the epidemiologic literature published between 1970 and July 1992. Comparison between studies was complicated by differences in study design, definitions of obesity, and analytic methods used. Although the correlations between anthropometric measures of obesity in childhood and those in adulthood varied considerably among studies, the associations were consistently positive. RESULTS: About a third (26 to 41%) of obese preschool children were obese as adults, and about half (42 to 63%) of obese school-age children were obese as adults. For all studies and across all ages, the risk of adult obesity was at least twice as high for obese children as for nonobese children. The risk of adult obesity was greater for children who were at higher levels of obesity and for children who were obese at older ages. CONCLUSION: The wide range of estimates in this literature are, in part, due to differences in study designs, definitions of obesity, ages at which participants were measured, intervals between measurements, and population and cultural differences.

Adolescent↗