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Biomedical subjects

G A Colditz

Publications and source records attributed to G A Colditz.

At least 91 records · Page 5Linked to original sources
PubMed2000

Prospective study of talc use and ovarian cancer.

BACKGROUND: Perineal talc use has been associated with an increased risk of ovarian cancer in a number of case-control studies; however, this association remains controversial because of limited supporting biologic evidence and the potential for recall bias or selection bias in case-control studies. In this study, we conducted a prospective analysis of perineal talc use and the risk of ovarian cancer. METHODS: The Nurses' Health Study is a prospective study of 121 700 female registered nurses in the United States who were aged 30-55 years at enrollment in 1976. Talc use was ascertained in 1982 by use of a self-administered questionnaire: after exclusions, 78 630 women formed the cohort for analysis. Three hundred seven epithelial ovarian cancers subsequently diagnosed in this cohort through June 1, 1996, were confirmed by medical record review and met inclusion criteria. Proportional hazards models by use of pooled logistic regression were used to derive relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: In 1982, 40.4% (n = 31 789) of the cohort reported ever using talc, and 14.5% (n = 11 411) reported ever using talc daily. We observed no overall association with ever talc use and epithelial ovarian cancer (multivariate RR = 1.09; 95% CI = 0.86-1.37) and no increase in risk of ovarian cancer with increasing frequency of use. There was a modest elevation in risk for ever talc use and invasive serous ovarian cancer (multivariate RR = 1.40; 95% CI = 1.02-1.91). The risk of epithelial ovarian cancer for talc users was not greater among women who had never had a tubal ligation (multivariate RR = 0.97; 95% CI = 0.71-1.32). CONCLUSION: Our results provide little support for any substantial association between perineal talc use and ovarian cancer risk overall; however, perineal talc use may modestly increase the risk of invasive serous ovarian cancer.

Adult↗
PubMed2000

Family dinner and diet quality among older children and adolescents.

CONTEXT: The proportion of children eating dinner with their families declines with age and has decreased over time. Few data exist concerning the nutritional effect of eating family dinner. OBJECTIVE: To examine the associations between frequency of eating dinner with family and measures of diet quality. DESIGN: Cross-sectional. SETTING: A national convenience sample. PARTICIPANTS: There were 8677 girls and 7525 boys in the study, aged 9 to 14 years, who were children of the participants in the ongoing Nurses' Health Study II. MAIN OUTCOME MEASURES: We collected data from a self-administered mailed survey, including food and nutrient intakes from a validated semiquantitative food frequency questionnaire. Main outcome measures included servings per day of selected foods and food groups, daily intakes of selected macronutrients and micronutrients, and frequency of multivitamin use. RESULTS: Approximately 17% of participants ate dinner with members of their family never or some days, 40% on most days, and 43% every day. More than half of the 9-year-olds ate family dinner every day, whereas only about one third of 14-year-olds did so. In age- and sex-adjusted logistic regression models, the odds ratios associated with a frequency of family dinner of most days compared with never or some days, or every day compared with most days, were as follows: for eating at least 5 servings per day of fruits and vegetables, 1.45 (95% confidence interval [CI], 1.37-1.53); for eating any fried foods away from home, 0.67 (95% CI, 0.64-0.70); and for drinking any soda, 0.73 (95% CI, 0.66-0.80). Multiple linear regression showed that an increased frequency of family dinner was also associated with substantially higher intake of several nutrients, including fiber, calcium, folate, iron, vitamins B6, B12, C, and E; lower glycemic load; and lower intake of saturated and trans fat as a percentage of energy. We observed little or no effect on intakes of whole dairy products, red meat, or snack foods. Patterns were similar for boys and girls. CONCLUSIONS: Eating family dinner was associated with healthful dietary intake patterns, including more fruits and vegetables, less fried food and soda, less saturated and trans fat, lower glycemic load, more fiber and micronutrients from food, and no material differences in red meat or snack foods.

Adolescent↗
PubMed2000

Dietary essential fatty acids, long-chain polyunsaturated fatty acids, and visual resolution acuity in healthy fullterm infants: a systematic review.

BACKGROUND: Biologically active neural tissue is rich in docosahexaenoic acid (DHA), an omega-3 long-chain polyunsaturated fatty acid (LCPUFA). We conducted a systematic review to examine the nature of discordant results from studies designed to test the hypothesis that dietary DHA leads to better performance on visually-based tasks in healthy, fullterm infants. We also conducted a meta-analysis to derive combined estimates of behavioral- and electrophysiologic-based visual resolution acuity differences and sample sizes that would be useful in planning future research. STUDY DESIGN AND METHODS: Twelve empirical studies on LCPUFA intake during infancy and visual resolution acuity were identified through bibliographic searches, examination of monograph and review article reference lists, and written requests to researchers in the field. Works were reviewed for quality and completeness of information. Study design and conduct information was extracted with a standardized protocol. Acuity differences between groups consuming a source of DHA and groups consuming DHA-free diets were calculated as a common outcome from individual studies; this difference score was evaluated against a null value of zero and then used, with the method of DerSimonian and Laird (Meta-analysis in clinical trials. Control Clin Trials 1986;7:177-188), to derive combined estimates of visual resolution acuity differences within seven age categories. RESULTS OF RANDOMIZED COMPARISONS: The combined visual resolution acuity difference measured with behaviorally based methods between DHA-supplemented formula fed groups and DHA-free formula fed groups is 0.32+/-0.09 octaves (combined difference+/-S.E.M., P=0.0003) at 2 months of age. The direction of this value indicates higher acuity in DHA-fed groups. RESULTS OF NON-RANDOMIZED STUDY DESIGNS: The combined visual resolution acuity difference measured with behaviorally based methods between human milk fed groups and DHA-free formula fed groups is 0.49+/-0.09 octaves (P< or =0.000001) at 2 months of age and 0.18+/-0.08 octaves (P=0.04) at 4 months of age. Acuity differences for electrophysiologic-based measures are also greater than zero at 4 months (0.37+/-0.16 octaves, P=0.02). CONCLUSION: Some aspect of dietary n-3 intake is associated with performance on visual resolution acuity tasks at 2, and possibly, 4 months of age in healthy fullterm infants. Whether n-3 intake confers lasting advantage in the development of visually based processes is still in question.

Bottle Feeding↗
PubMed2000

Snoring and risk of cardiovascular disease in women.

OBJECTIVES: To examine prospectively the association between snoring and incidence of cardiovascular disease (CVD) in women. BACKGROUND: Whether snoring increases risk of CVD remains unclear; most previous studies have been small, not prospective and limited to men. METHODS: Seventy-one thousand seven hundred seventy-nine female nurses 40 through 65 years of age and without previously diagnosed CVD or cancer at baseline in 1986 were followed up for eight years. Frequency of snoring was assessed using mailed questionnaires at baseline. RESULTS: During eight years of follow-up, we documented 1,042 incident cases of major CVD events (644 coronary heart disease [CHD] and 398 stroke). Compared with nonsnorers, the age-adjusted relative risks (RRs) of CVD were 1.46 (95% confidence interval 1.23 to 1.74) for occasional snorers and 2.02 (1.62 to 2.53) for regular snorers. The age-adjusted RRs of CHD were 1.43 (1.15 to 1.77) for occasional snorers and 2.18 (1.65 to 2.87) for regular snorers. The age-adjusted RRs of stroke were 1.60 (1.21 to 2.12) and 1.88 (1.29 to 2.74), respectively. After further adjustment for smoking, body mass index (BMI) and other covariates, the positive association between snoring and CVD was attenuated but remained statistically significant (RRs of CVD were 1.20 [1.01 to 1.43] for occasional snorers and 1.33 [1.06-1.67] for regular snorers. CONCLUSIONS: These data suggested that snoring is associated with a modest but significantly increased risk of CVD in women, independent of age, smoking, BMI and other cardiovascular risk factors. While further study is needed to elucidate the biological mechanism underlying this association, snoring may help clinicians identify individuals at higher risk for CVD.

Adult↗
PubMed2000

A prospective study of alcohol consumption and cataract extraction among U.S. women.

PURPOSE: Alcohol consumption has been implicated in the pathogenesis of cataract in some, but not all analytic studies. To date, no prospective analysis of the relationship between alcohol consumption and cataract has been conducted in women. METHODS: We examined the association between alcohol consumption and cataract extraction in a prospective cohort of female registered nurses. In 1980, 50,461 women were included and others were added as they became 45 years of age for a total of 77,466 women. Information on alcohol consumption and incidence of senile cataract extraction was ascertained during 12 years of follow-up with biennial questionnaires. RESULTS: We observed 1468 cases of cataract extraction in 761,036 person-years of follow-up. Compared to nondrinkers, those consuming alcohol were not at increased risk of cataract, even up to 25 grams or more per day (2 or more drinks). Results remained unchanged after controlling for cataract risk factors including cigarette smoking, body mass index, and diabetes. When risk was examined for specific cataract subtypes only, those in the highest category of consumption had a multivariate relative risk of 1.10 for nuclear cataracts and 1.50 for posterior subcapsular cataracts only. CONCLUSIONS: These prospective data suggest that there is no substantial overall increased risk of senile cataract due to alcohol intake. The possibility that alcohol consumption leads to a modest increased risk of posterior subcapsular type opacities requiring extraction merits further exploration.

Adult↗
PubMed2000

Harvard report on cancer prevention volume 4: Harvard Cancer Risk Index. Risk Index Working Group, Harvard Center for Cancer Prevention.

OBJECTIVE: Prediction of cancer risk is a minor component of current health risk appraisals. Perception of individual cancer risk is poor. A Cancer Risk Index was developed to predict individual cancer risk for cancers accounting for 80% of the cancer burden in the United States. METHODS: We used group consensus among researchers at the Harvard Medical School and Harvard School of Public Health to identify risk factors as definite, probable and possible causes of cancer. Risk points were allocated according to the strength of the causal association and summed. Population average risk of cancer and cumulative 10-year risk was obtained from SEER data. Individual ranking relative to the population average was determined. The risk index was evaluated for validity using colon cancer incidence in prospective cohort data. RESULTS: The Harvard Cancer Risk Index provides a broad classification of cancer risk. Validation against cohort data shows good agreement for colon cancer. CONCLUSION: The Harvard Cancer Risk Index offers a simple estimation of personal risk of cancer. It may help inform users of the major risk factors for cancer and identify changes in lifestyle that will reduce their risk. It offers the potential for tailored health-promotion messages.

Adult↗
PubMed2000

Proportion of colon cancer risk that might be preventable in a cohort of middle-aged US men.

OBJECTIVE: Diet and lifestyle likely play major roles in colon cancer incidence; however, the proportion of colon cancer risk that might be preventable is unknown. Thus, we estimated the proportion of colon cancer risk among men in the prospective Health Professionals Follow-up Study that might be attributable to a constellation of modifiable risk factors, and thus might be preventable. METHODS: We included 47,927 men aged 40-75 years in 1986, among whom we confirmed 411 colon cancer cases from 1986 to 1996. Risk factors considered were obesity, physical inactivity, alcohol consumption, early adulthood cigarette smoking, red meat consumption, and low intake of folic acid from supplements. We calculated a risk score that was the sum across the six risk factors of the values of 1 (better exposure) to 5 (worse exposure) corresponding to the exposure category. We entered the risk score into a logistic regression model and estimated the population attributable risk percent (PAR%) using the method of Bruzzi et al. RESULTS: After adjusting for age and family history of colorectal cancer and comparing the risk score for the combined six modifiable colon cancer risk factors at or above the approximate 20th, 10th, or 5th percentiles vs. below, the PAR% increased from 39% (95% confidence interval (CI) = 23-58%), to 48% (95% CI = 25-71%), to 55% (95% CI = 27-80%), respectively. Using a second method in which we used cut-points consistent with general-good health behaviors for each risk factor, comparing men with at least one risk factor to men without any risk factors (3.1% of the men), the PAR% was 71% (95% CI = 33-92%). CONCLUSION: The findings from this analysis suggest that, if all the members of this cohort of middle-aged US men had a modifiable exposure distribution comparable to the men with low risk scores, a large proportion of colon cancer risk might be avoidable. Additional study is required to determine whether making changes in these six risk factors now would reduce the risk of colorectal neoplasia, or whether the proportion of colon neoplasia that might be avoidable would be similar in populations with different characteristics.

Adenoma↗
PubMed2000

Bowel movement, use of laxatives and risk of colorectal adenomatous polyps among women (United States).

BACKGROUND: Infrequent bowel movements and use of laxatives have been hypothesized to increase risk of colorectal neoplasia. However, the few existing epidemiologic studies in humans have been inconclusive. PURPOSE: To investigate prospectively the associations of bowel movement frequency and laxative use with the occurrence of adenomatous colorectal polyps in women. METHODS: A total of 17,400 women 36-61 years of age, without previous diagnosis of cancer or polyps, responded to a mailed questionnaire in 1982 that assessed bowel movement frequency and use of laxatives and had an endoscopy between 1984 and 1996. Between 1984 and 1996, 906 cases of adenomatous polyps (496 classified as small (< 1 cm), 358 classified as large (> or = 1 cm) and 52 unclassified) were documented. Relative risks (RRs) of adenomas and 95% confidence intervals (CIs) were calculated using logistic regression. RESULTS: After controlling for adenoma risk factors, the multivariate RRs associated with having bowel movements every third day or less compared to once daily were 0.9 (95% CI: 0.7-1.2) for total colorectal adenomas, 1.0 (95% CI: 0.7-1.5) for large adenomas and 1.0 (95% CI: 0.7-1.3) for adenomas of the colon only. The multivariate RRs associated with weekly to daily laxative use compared to never use were 0.9 (95% CI: 0.7-1.1) for total colorectal adenomatous polyps, 1.0 (95% CI: 0.7-1.5) for large adenomas and 0.8 (95% CI: 0.6-1.2) for colon adenomatous polyps only. CONCLUSION: These findings do not support an association between infrequent bowel movement or laxative use and risk of colorectal adenomas.

Adenomatous Polyps↗
PubMed2000

Diet and basal cell carcinoma of the skin in a prospective cohort of men.

BACKGROUND: Low intake of fat and high intake of specific vitamins have been hypothesized to reduce risk of basal cell carcinoma of the skin (BCC). OBJECTIVE: Our objective was to examine intakes of fat, antioxidant nutrients, retinol, folate, and vitamin D in relation to risk of BCC. DESIGN: In 1986, diet was assessed by a validated food-frequency questionnaire in 43217 male participants of the Health Professionals Follow-up Study who were 40-75 y of age and free of cancer. During 8 y of follow-up, we ascertained 3190 newly diagnosed cases of BCC. RESULTS: Total fat consumption was associated with a lower risk of BCC [relative risk (RR): 0.81; 95% CI: 0.72, 0.90 for the highest compared with the lowest quintile of intake; P for trend < 0.001). Simultaneous modeling of specific fatty acids suggested that this inverse association was limited to monounsaturated fat (RR: 0.79; 95% CI: 0.65, 0.96; P for trend = 0. 02); saturated and polyunsaturated fat were not associated with BCC risk. Folate intake was associated with a slightly higher risk of BCC (RR: 1.19; 95% CI: 1.01, 1.40; P for trend = 0.11), whereas alpha-carotene was associated with a slightly lower risk (RR: 0.88; 95% CI: 0.79, 0.99; P for trend = 0.01). Intakes of long-chain n-3 fatty acids, retinol, vitamin C, vitamin D, or vitamin E were not materially related to BCC risk. CONCLUSIONS: These findings do not support the hypothesis that diets low in fat or high in specific vitamins lower risk of BCC.

Adult↗
PubMed2000

Intake of specific carotenoids and risk of lung cancer in 2 prospective US cohorts.

BACKGROUND: Carotenoids may reduce lung carcinogenesis because of their antioxidant properties; however, few studies have examined the relation between intakes of individual carotenoids and lung cancer risk. OBJECTIVE: The aim of this study was to examine the relation between lung cancer risk and intakes of alpha-carotene, beta-carotene, lutein, lycopene, and beta-cryptoxanthin in 2 large cohorts. DESIGN: During a 10-y follow-up period, 275 new cases of lung cancer were diagnosed in 46924 men; during a 12-y follow-up period, 519 new cases were diagnosed in 77283 women. Carotenoid intakes were derived from the reported consumption of fruit and vegetables on food-frequency questionnaires administered at baseline and during follow-up. The data were analyzed separately for each cohort and the results were pooled to compute overall relative risks (RRs). RESULTS: In the pooled analyses, alpha-carotene and lycopene intakes were significantly associated with a lower risk of lung cancer; the association with beta-carotene, lutein, and beta-cryptoxanthin intakes were inverse but not significant. Lung cancer risk was significantly lower in subjects who consumed a diet high in a variety of carotenoids (RR: 0.68; 95% CI: 0.49, 0.94 for highest compared with lowest total carotenoid score category). Inverse associations were strongest after a 4-8-y lag between dietary assessment and date of diagnosis. In subjects who never smoked, a 63% lower incidence of lung cancer was observed for the top compared with the bottom quintile of alpha-carotene intake (RR: 0.37; 95% CI: 0.18, 0.77). CONCLUSION: Data from 2 cohort studies suggest that several carotenoids may reduce the risk of lung cancer.

Adult↗
PubMed2000

Adherence to the Dietary Guidelines for Americans and risk of major chronic disease in women.

BACKGROUND: Little is known about the overall health effects of adherence to the Dietary Guidelines for Americans. The healthy eating index (HEI), developed at the US Department of Agriculture, measures how well Americans' diets conform to these guidelines. OBJECTIVE: We tested whether the HEI (scores range from 0 to 100; 100 is best) calculated from food-frequency questionnaires (HEI-f) would predict risk of major chronic disease in women. DESIGN: A total of 67272 US female nurses who were free of major disease completed detailed questionnaires on diet and chronic disease risk factors in 1984 and repeatedly over 12 y. Major chronic disease was defined as fatal or nonfatal cardiovascular disease (myocardial infarction or stroke, n = 1365), fatal or nonfatal cancer (n = 5216), or other nontraumatic deaths (n = 496), whichever came first. We also examined cardiovascular disease and cancer as separate outcomes. RESULTS: After adjustment for smoking and other risk factors, the HEI-f score was not associated with risk of overall major chronic disease in women [relative risk (RR) = 0.97; 95% CI: 0.89, 1.06 comparing the highest with the lowest quintile of HEI-f score]. Being in the highest HEI-f quintile was associated with a 14% reduction in cardiovascular disease risk (RR = 0.86; 95% CI: 0.72, 1. 03) and was not associated with lower cancer risk (RR = 1.02; 95% CI: 0.93, 1.12). CONCLUSION: These data suggest that adherence to the 1995 Dietary Guidelines for Americans, as measured by the HEI-f, will have limited benefit in preventing major chronic disease in women.

Adult↗
PubMed2000

Activity, dietary intake, and weight changes in a longitudinal study of preadolescent and adolescent boys and girls.

OBJECTIVE: To examine the role of physical activity, inactivity, and dietary patterns on annual weight changes among preadolescents and adolescents, taking growth and development into account. STUDY DESIGN: We studied a cohort of 6149 girls and 4620 boys from all over the United States who were 9 to 14 years old in 1996. All returned questionnaires in the fall of 1996 and a year later in 1997. Each child provided his or her current height and weight and a detailed assessment of typical past-year dietary intakes, physical activities, and recreational inactivities (TV, videos/VCR, and video/computer games). METHODS: Our hypotheses were that physical activity and dietary fiber intake are negatively correlated with annual changes in adiposity and that recreational inactivity (TV/videos/games), caloric intake, and dietary fat intake are positively correlated with annual changes in adiposity. Separately for boys and girls, we performed regression analysis of 1-year change in body mass index (BMI; kg/m(2)). All hypothesized factors were in the model simultaneously with several adjustment factors. RESULTS: Larger increases in BMI from 1996 to 1997 were among girls who reported higher caloric intakes (.0061 +/-.0026 kg/m(2) per 100 kcal/day; beta +/- standard error), less physical activity (-.0284 +/-.0142 kg/m(2)/hour/day) and more time with TV/videos/games (.0372 +/-.0106 kg/m(2)/hour/day) during the year between the 2 BMI assessments. Larger BMI increases were among boys who reported more time with TV/videos/games (.0384 +/-.0101) during the year. For both boys and girls, a larger rise in caloric intake from 1996 to 1997 predicted larger BMI increases (girls:.0059 +/-.0027 kg/m(2) per increase of 100 kcal/day; boys:.0082 +/-.0030). No significant associations were noted for energy-adjusted dietary fat or fiber. CONCLUSIONS: For both boys and girls, a 1-year increase in BMI was larger in those who reported more time with TV/videos/games during the year between the 2 BMI measurements, and in those who reported that their caloric intakes increased more from 1 year to the next. Larger year-to-year increases in BMI were also seen among girls who reported higher caloric intakes and less physical activity during the year between the 2 BMI measurements. Although the magnitudes of these estimated effects were small, their cumulative effects, year after year during adolescence, would produce substantial gains in body weight. Strategies to prevent excessive caloric intakes, to decrease time with TV/videos/games, and to increase physical activity would be promising as a means to prevent obesity.

Adolescent↗
PubMed2000

Meta-analysis of dietary essential fatty acids and long-chain polyunsaturated fatty acids as they relate to visual resolution acuity in healthy preterm infants.

OBJECTIVE: To derive combined estimates of visual resolution acuity differences between healthy preterm infants consuming different compositions and ratios of essential fatty acids (EFAs) and docosahexaenoic acid (DHA), an omega-3 (n-3) long-chain polyunsaturated fatty acid (LCPUFA). DATA SOURCES: Electronic biomedical reference database (Medline and Health Star from 1965 to July 1999) searches with index terms omega-3, n-3, infant, vision, acuity, and human. Current review article, monograph, and book chapter bibliography/reference section hand searches. STUDY SELECTION: A total of 5 original articles and 4 review chapters were reviewed for details on study design, conduct, and outcome. Four prospective trials of EFA/LCPUFA supplementation were included in these analyses. For behaviorally based outcomes, there were 2 randomized comparisons each at </=1, 2, 6, 9, and 12 months of corrected age and 4 randomized comparisons at 4 months of corrected age. For electrophysiologically based outcomes (visual-evoked potential), there were 2 randomized comparisons each at </=1 and approximately 4 months of corrected age. DATA EXTRACTION: Dietary composition and EFA/LCPUFA balance, study design, and analytic characteristics (duration of feeding, source of EFAs/LCPUFAs, number of subjects in study population, number of subjects analyzed, and basis for estimating age), and experiment-based characteristics (location, number or sites, design, vision tests employed, testing protocol, and ophthalmic examination) were recorded independently by 2 researchers with a standardized protocol. DATA SYNTHESIS: The relative difference in visual resolution acuity between groups of infants who received a source of dietary EFAs/LCPUFAs and groups who did not was computed and then analyzed with the DerSimonian and Laird random-effects method. RESULTS: Analysis of the randomized comparisons (DHA-supplemented formula vs DHA-free formula) showed significant differences in visual resolution acuity at 2 and 4 months of age. Combined estimates of behaviorally based visual resolution acuity differences at these ages were.47 +/-.14 octaves and.28 +/-.08 octaves, respectively. A 1-octave difference is a reduction in the width of the stimulus elements by 50%. CONCLUSION: These results support efficacy of n-3 LCPUFA intake in early visual system development, although supplementation safety issues still must be addressed through larger randomized trials. Whether n-3 intake confers lasting advantage in visually based process development across the life-span is still to be determined.

Dietary Supplements↗