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T Byers

Publications and source records attributed to T Byers.

At least 127 records · Page 7Linked to original sources
PubMed1985

Diabetes mellitus and cancer risk: a multisite case-control study.

The association between a prior diagnosis of diabetes mellitus and cancer was examined in a large multisite case-control study based on interviews of 8220 white males and 6690 white females aged 30-89 who were admitted to Roswell Park Memorial Institute between 1957 and 1965 for the diagnosis and treatment of cancer. A prior history of diabetes mellitus as diagnosed by a physician was examined as a risk factor for cancer by conducting sex- and site-specific comparisons with a common control group of 2363 white males and 2475 white females who were admitted to the same hospital during the same years, but were found not to have cancer. The findings are consistent with previous studies which have shown diabetes to be a risk factor for cancer of the uterine corpus. A positive association was also noted between diabetes and cancer of the vulva and vagina. The evidence for excess estrogen levels as the underlying mechanism for increased risk of uterine and vulvo-vaginal cancer is reviewed. No consistent association between diabetes and pancreatic cancer was observed in this study, except when those cases in which diabetes was diagnosed within a year before the diagnosis of pancreatic cancer were included. This suggests that diabetes may be an early presenting sign of pancreatic cancer rather than a risk factor. A positive association between prior diagnosis of diabetes was noted for kidney cancer and nonmelanoma skin cancer in females only. No association between type of treatment (i.e. insulin, oral agents) and cancer risk was noted.

Adult↗
PubMed1985

Lactation and breast cancer. Evidence for a negative association in premenopausal women.

The authors report a case-control study of breast cancer based on an analysis of data collected by interview between the years 1957-1965 from women residing in the communities of Buffalo and Kenmore, New York. Prior reproductive factors, including a detailed lactation history, were examined for 453 white females with breast cancer and 1,365 white females without breast cancer who were selected randomly from the population of Buffalo and Kenmore. There is evidence of a negative association between length of nursing and breast cancer risk in premenopausal women which is not seen in the postmenopausal women. This apparent "protective" effect of lactation persists after statistical control for the potential confounding factors of age, parity, age at first pregnancy, age at menarche, and education. Cases are more likely than controls to have reported unsuccessful lactations due to "insufficient milk." The findings of this study, in conjunction with the authors' review of previously published studies that have examined prior lactation as related to breast cancer risk, suggest that there may be an independent negative association between nursing and subsequent breast cancer risk in premenopausal women. Whether this means that breast feeding is protective or that some women who are unsuccessful at lactation are at increased risk for subsequent breast cancer is not clear. A detailed reanalysis of existing data and more careful attention to detailed prior breast function/dysfunction in future studies are recommended.

Adolescent↗
PubMed1985

Assessing nutrient intake with an abbreviated dietary interview.

There is considerable interest in developing a means of assessing dietary intake of specific nutrients with minimal time and expense in epidemiologic studies. Using data from 1,682 individuals who were interviewed using an extensive food frequency dietary history, the authors examined the question of how many foods might be minimally required in order to estimate specific nutrient intakes for epidemiologic purposes. Nutrient indices were constructed for vitamins A and C, dietary fiber, fat, protein, and total calories based on 128 foods included in the interview. They found that a large fraction of the variability of nutrient intake in this population could be explained by a small number of foods. An abbreviated dietary history ascertaining the intake of as few as 15-20 food items may be all that is required in order to test the association between disease outcome and the intake of a single nutrient.

Age Factors↗
PubMed1984

Dietary vitamin A and lung cancer risk: an analysis by histologic subtypes.

A case-control study was conducted based on 427 white males with lung cancer of the squamous, small cell, and adenocarcinoma histologic subtypes and 1,094 white male controls admitted to Roswell Park Memorial Institute between the years 1957 and 1965. The relation between selected dietary factors and lung cancer risk was examined for each histologic subtype while controlling for past cigarette use. Dietary vitamin A was found to be negatively associated with risk for squamous cell and small cell carcinoma, but not for adenocarcinoma of the lung. No significant association was observed, however, between dietary vitamin C, fats, or fiber and any of the lung cancer subtypes. These results suggest that the apparent protective effect of vitamin A in lung cancer may be histologic type-specific.

Adenocarcinoma↗
PubMed1984

Towards the dietary prevention of cancer: contributions of epidemiology.

There may be a considerable potential for the prevention of cancer through dietary modifications or chemo-prevention strategies. The epidemiological methods which have been used in the study of the relation between diet and cancer are briefly reviewed and the scientific basis for major hypotheses linking diet to cancer are summarized. Clinical trials, now being considered to assess the potential for the prevention of cancer by dietary supplementation or modification, do not have many of the uncertainities of other methods, yet there are many potential difficulties in both the conduct and interpretation of such trials. These limitations are discussed as well as the problem in making general dietary recommendations for the prevention of cancer based on current knowledge. A more complete understanding of the effect of diet on cancer risk will likely emerge only through a more integrated and interdisciplinary approach in future studies.

Ascorbic Acid↗
PubMed1983

Diet in the epidemiology of carcinoma of the prostate gland.

In vivo, in vitro, prospective, and retrospective epidemiologic inquiries have suggested that retinoids inhibit cancer, and fats have been hypothesized to enhance and ascorbic acid to reduce cancer risk. Comparison of 260 patients from Buffalo with cancer of the prostate gland was made with two different control series of similar size and age distribution. Regardless of the control group, risk of prostate cancer gained with increases in ingestion of retinoids, animal fats, and vitamin C. These anomalous findings may be due to peculiarities in methodology. From the possible specificity of effect of the nutrients studied, as shown in experimental animals and in vitro, a hypothesis could be made that a substance like vitamin A or C, which may inhibit certain cancers, also may enhance risk of other cancer types or have neither effect.

Adult↗
PubMed1983

Diet and smoking in the epidemiology of cancer of the cervix.

This study of 513 white cervical cancer patients and 490 white hospitalized controls considered, with adjustment for marital history and parity, the effects of smoking and dietary characteristics on the relative risk of developing cervical cancer. Although smoking was shown to be positively associated with risk, no dose-response relationship was evident. The frequency of consumption of cruciferous vegetables was positively associated with risk. Respondent reports of the frequency of prior ingestion of several food items were used in constructing crude indices of exposure to basic nutrients; the index of beta-carotene exposure was negatively associated with risk, whereas the index of fat consumption was positively associated with risk.

Alcohol Drinking↗
PubMed1983

A case-control study of dietary and nondietary factors in ovarian cancer.

A case-control study is presented that estimates ovarian cancer risk for various factors, including diet. Data collected by interview between 1957 and 1965 for 274 white women aged 30-79 years with epithelial carcinoma of the ovary are compared to data similarly collected for 1,034 hospital controls. Relative risk estimates are presented for the total group as well as for premonopausal (ages 30-49) and postmenopausal (ages 50-79) are groups. In the total group, cancer risk increased with increasing age at first marriage (P less than .01) and previous history of benign breast disease (P less than 0.1), and risk decreased with increasing number of previous pregnancies (P less than .01). In the 50- to 79-year age group, a marginally significant trend for decreasing risk with increasing obesity was observed (P less than .10). There was no significant risk (i.e., P less than .10) associated with the consumption of alcohol, cigarettes, coffee, tea, total dietary protein, vitamin C, or fat at any age. In the 30- to 49-year age group only, increased risk (P less than .01) was seen in women reporting diets low in fiber and vitamin A from fruit and vegetable sources. Multiple regression analysis demonstrated that the apparent protective effect of vitamin A in the 30- to 49-year age group (but not dietary fiber) was independent of the nondietary factors analyzed in this study (P less than .05).

Adult↗
PubMed1982

Diet in the epidemiology of breast cancer.

A variety of studies have shown that diets high in fat, particularly polyunsaturated, have enhanced the production of tumors in animals challenged with chemical carcinogens. Other studies have found an apparent contradiction of no difference in the incidence of breast cancer among women with varying levels of serum cholesterol as measured decades earlier. The present study concerns 2024 breast cancer cases and 1463 control patients without neoplasms or pathology of the reproductive and digestive organs, seen at Roswell Park Memorial Institute from 1958 to 1965. Based upon the assessments of their varying ingestion of fats from their own reports of diets, no difference in risk was found. Similarly, there was no difference in risk of breast cancer associated with ingesting diets containing various levels of either vitamin C or the cruciferous vegetables. Risk for breast cancer in women 55 years of age and older increased somewhat with decreases in ingestion of foods containing vitamin A.

Aging↗
PubMed1982

Parity and colorectal cancer risk in women.

A case-control study is reported of reproductive history and colorectal cancer risk based on information obtained from interviews with white women 40--79 years old who were admitted to Roswell Park Memorial Institute between the years 1957 and 1965. Women with the primary diagnosis of carcinoma of the colon (n = 284) and carcinoma of the rectum (n = 270) did not differ significantly in their prior reproductive histories as compared to those of a control group of women (n = 1,763) with nonneoplastic diseases not affecting the breast or reproductive sites. The peritinent literature suggesting a parity--colorectal cancer association in women is reviewed. The conclusion reached is that the evidence for a parity-colorectal cancer association is equivocal; but that if such an association exists, it is probably weaker than that seen for cancers of the breast, ovary, and uterine corpus.

Adult↗
PubMedDate not supplied

The correspondence between coronary heart disease mortality and risk factor prevalence among states in the United States, 1991-1992.

OBJECTIVE: This study aimed to examine the correspondence between seven established risk factors for coronary heart disease (CHD) and CHD mortality among the states in the United States. An ecologic analysis relating CHD risk factor prevalences to CHD mortality rates among 49 states was undertaken in 1991-1992. METHODS: Approximately 68,000 men and women ages 45-74 were randomly sampled and interviewed by telephone in surveys conducted in 49 states in 1991 and 1992. From these interviews, we estimated state-specific prevalences of smoking, overweight, physical inactivity, hypertension, elevated cholesterol, diabetes, and alcohol abstinence. These seven CHD risk factors were also combined to create a CHD risk index for each state. The main outcome measures were mortality rates from CHD (ICD9 codes 410.0-414.9) in each of 49 states in 1991-1992 for men and women ages 45-74. The analysis was based on multiple linear regression and Spearman's rank-order correlations between the CHD risk factor prevalences, the combined CHD risk index, and the CHD mortality rates among the 49 states. RESULTS: The prevalences of most of the CHD risk factors correlated with CHD mortality rates in the expected directions, and correlations were similar for men and women. The CHD risk index correlated strongly with CHD mortality for both men (r = 0.75) and women (r = 0.80). CONCLUSION: About 60% of the variance in CHD mortality between the states in the United States (56% for men and 64% for women) is attributable to differences between the states in the prevalences of seven established risk factors for CHD. As state health agencies prioritize resources for chronic disease prevention programs, they should consider the potential benefits of increased efforts to reduce the prevalences of modifiable CHD risk factors in their populations to reduce CHD mortality.

Aged↗