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F de Waard

Publications and source records attributed to F de Waard.

At least 37 records · Page 2Linked to original sources
PubMed1992

A collaborative case-control study of nutrient intake and pancreatic cancer within the search programme.

Case-control studies of pancreatic cancer were conducted in 5 populations with moderate to high rates and differing dietary practices, using a common protocol and questionnaire. Comprehensive diet histories were completed for a total of 802 cases and 1669 controls identified in Adelaide (Australia), Montreal and Toronto (Canada), Utrecht (The Netherlands) and Opole (Poland). Positive associations were observed with intake of carbohydrates and cholesterol, and inverse associations with dietary fiber and vitamin C. These relationships were generally consistent among the 5 studies, and showed statistically significant and generally monotonic dose-response relationships. The relative risks for highest vs. lowest quintile of intake were estimated for carbohydrates to be 2.57 (95% confidence interval 1.64-4.03), cholesterol 2.68 (1.72-4.17), dietary fiber 0.45 (0.30-0.63), and vitamin C 0.53 (0.38-0.76). The consistency, strength, and specificity of these associations provides evidence for the hypothesis that some or all of these dietary factors may alter the risk of pancreatic cancer.

Adult↗
PubMed1992

Body measurements, estrogen availability and the risk of human breast cancer: a case-control study.

Recent studies on lifestyle-related mechanisms involved in cardiovascular risk offer important clues for a better understanding of breast-cancer epidemiology. Central body-fat distribution promoted by an affluent dietary intake and a sedentary lifestyle over many years is related to elevated serum triglycerides and free fatty acids, with lower levels of sex-hormone-binding globulin (SHBG). The resulting greater availability of estradiol not bound to SHBG could help to explain the high breast-cancer incidence in Western industrialized countries. We conducted a case-control study comparing 225 women aged 38 to 75 years with operable (stage I or II) breast cancer and 441 women of the same age having no breast cancer who participated in a population-based breast-cancer screening program. Body fatness, as measured by body mass index (BMI), fat distribution as measured by waist-to-hip girth ratio (WHR), body height, serum lipids, SHBG and the available fraction of estradiol were analyzed in a conditional logistic regression, together with family history for breast cancer, reproductive history and smoking. Post-menopausal cases showed no difference in body fatness (BMI), but a significant preponderance of central adiposity (WHR). In contrast, pre-menopausal cases were significantly leaner, but had a similar body-fat distribution as compared with controls. In all women, WHR, and less strongly BMI, was positively correlated with serum levels of triglycerides and available estradiol fractions. An independent, positive linear correlation between body height and relative risk (RR) was observed. Moreover, a significant correlation between SHBG and menarcheal age was seen in cases, but not in controls. These data support our hypothesis that lifestyle relates to breast-cancer risk by metabolic-endocrine mechanisms which modulate the availability of individual sex-steroid concentrations in plasma. The findings of height as a risk factor and adult SHBG levels being correlated with menarcheal age suggest that lifestyle factors promoting breast-cancer development already act around puberty. The leanness of pre-menopausal cases awaits further explanation.

Adult↗
PubMed1992

Risk of strut fracture of Björk-Shiley valves.

The incidence of and factors that predispose to outlet strut fracture of Björk-Shiley heart valves are still not known. To obtain such information a retrospective cohort study was conducted on all 2303 patients in the Netherlands with a 60 degrees convexo-concave (60 degrees CC) or a 70 degrees convexo-concave (70 degrees CC) Björk-Shiley heart valve. Patients have been followed-up for a mean of 6.6 years (range 1-4271 days). 42 cases of mechanical failure due to outlet strut fracture have been recorded-6 of the 7 patients with fracture of the aortic valve died, as did 18 of the 35 patients with fracture of the mitral valve. Multivariate analysis identified wide opening angle (70 degrees), large valve size (greater than or equal to 29 mm diameter), and young age (less than 50 years) as risk factors for outlet strut fracture. For large 70 degrees CC mitral valves the cumulative risk of outlet strut fracture after 8 years was 17.4% (95% CI 9.1-31.6). Unlike previous findings, this excessive risk applied to late as well as to early batches of valves. In patients with a large 60 degrees CC mitral valve the cumulative risk after 8 years was 4.2% (95% CI 2.7-6.5). The incidence rate of outlet strut fracture in 60 degrees CC and 70 degrees CC valves (aortic and mitral) was constant over time. Overall survival since implantation was better for patients with 60 degrees CC prostheses than for those with 70 degrees CC prostheses; the adjusted hazard ratio for mortality for patients receiving a 70 degrees CC prosthesis was 1.5 (95% CI 1.1-2.0). Together with the low (24%) necropsy rate, this ratio suggests that the reported incidence of strut fracture for the 70 degrees CC valves is an underestimate. The data indicate that prophylactic replacement of 60 degrees CC and 70 degrees CC valves is advisable for selected groups of patients. Since the case-fatality rate is 50% for emergency replacement of faulty valves, patients suspected of Björk-Shiley heart-valve failure should be referred without delay to a cardiothoracic centre.

Adult↗
PubMed1992

Breast cancer after a negative screen: follow-up of women participating in the DOM Screening Programme.

First-round screening results for women participating in the DOM project (a screening programme for early detection of breast cancer) are described for the age groups 40-49 and 50-64 at entry. In the younger age group, a low pick-up rate (1.96 per 1000) in proportion to the expected incidence rate in the absence of screening (1.46 per 1000) was found. For the older age group, these rates were 4.25 and 2.03, respectively, per 1000. Interval cancers occurred (relatively) more frequently in younger women. After 2 years the ratio between interval-cancers and screen-detected tumours was about 1:1 in the younger age group and 1:2.5 in the older age group. These different results can be caused by too low a sensitivity of mammography and/or a higher tumour growth rate at a young age. The sensitivity of the screen at various periods of follow-up, was compared: a rapidly decreasing sensitivity of mammography was seen for women under the age of 50, in contrast to a slower decrease for women over this age. This rapid decrease may be caused by a relatively high tumour growth rate in younger women.

Adult↗
PubMed1992

Evaluation of a breast cancer screening programme--the DOM project.

In several studies it has been shown that breast cancer screening by means of mammography reduces breast cancer mortality. To ensure that when organising a service screening programme the aim is reached, it is necessary to control and monitor the process. This is possible by several methods. In this study, disease-free intervals and survival rates were used as monitoring tools. The DOM project, a breast cancer screening programme for women aged 50-64 years old at intake, started at the end of 1974. All breast cancer cases diagnosed between 1973 and 1989 were followed up to 1991. It is clear that disease-free interval and survival rates are proper predictors of the effects of screening on breast cancer mortality.

Breast Neoplasms↗
PubMed1992

Further evidence of benefits of a (non-randomised) breast cancer screening programme: the DOM project.

STUDY OBJECTIVE: The aim was to demonstrate the benefits of breast cancer screening on mortality. DESIGN: The study was an evaluation of a breast cancer screening programme by means of different approaches: (1) a case-control study, breast cancer deaths being the cases; (2) comparing the numbers of breast cancer deaths in screened and unscreened women; (3) comparing breast cancer mortality before and after start of the programme; (4) comparing breast cancer mortality in different large cities; (5) comparing screening activity with mortality reduction. SETTING: The setting was a breast cancer screening programme in the city of Utrecht, the DOM project, for women aged 50-64 years old at intake, birth cohort 1911-1925. The programme started in 1974, and there were five screening rounds up to 1984. Participation rate in the first round was 72% (14,697 women). MAIN RESULTS: (1) Screening was protective against dying from breast cancer, odds ratio 0.52, with a stronger effect in older women and no evidence of confounding; (2) risk ratio of dying from breast cancer for women in the response group was the same as the odds ratio, 0.52; (3) breast cancer death rate after the start of the project was nearly 20% lower than before the project started; after correcting for women who could not have benefited from screening the reduction was 33%; (4) a rise in breast cancer mortality in birth cohort 1911-1925 seen in other large cities without a screening programme due to aging of the cohort was not seen in the city of Utrecht; (5) mortality reduction followed the screening activity with a time lag of approximately 5 years. CONCLUSIONS: Early diagnosis of breast cancer by mammography reduces breast cancer mortality in women 50-64 years old at intake; different approaches to the evaluation of the project give different estimates of the screening effect, making clear that the effect depends on the intensity of the programme.

Breast Neoplasms↗
PubMed1992

Breast cancer in Europe: the importance of factors operating at an early age.

Breast cancer incidence varies considerably among European countries, with highest rates found in western and northern and lowest rates in eastern and southern European countries. The objective of this ecological correlation study was to investigate to what extent variation in breast cancer incidence within Europe can be attributed to differences in the prevalence of the following risk factors: age at menarche, age at first birth, parity, body height and body weight. The results of the study showed that particularly age at first birth and body height correlated positively and significantly with breast cancer incidence. If in eastern and southern European countries changes take place with respect to reproductive behaviour and nutritional status in the same way as has happened in western and northern European countries, breast cancer incidence in the countries included in this study may increase by 11%. This means that, by the time the 0- to 10-year-old female population in the European countries being studied reaches the age of 64, the number of women with breast cancer may be 1,198,369, which is almost 135,000 higher than would be the case if breast cancer risk remained stable.

Adult↗
PubMed1989

A prospective study on corpus luteum function and breast cancer risk.

A case-control study incorporated within a cohort study was undertaken to test the hypothesis that anovulation or decreased luteal function is associated with increased risk of breast cancer. A large population (n = 12,000) of apparently healthy women aged 40-49 collected a specimen of urine on day 22 of 3 consecutive menstrual cycles, or, in cases of amenorrhea, on 3 arbitrarily chosen days. These samples were stored at -20 degrees C. Subsequent screening of the women by mammography revealed 34 cases of breast cancer, and over the next 4 years a further 34 cases were reported to the cancer registry. Urine samples from 53 of these cases were assayed for pregnanediol and creatinine, and the results were compared with those for an equal number of matched controls. No differences between these groups were found in the pregnanediol/creatinine ratio. We conclude that our results do not support the hypothesis that women with luteal insufficiency are at increased risk for breast cancer. However, since breast cancer patients tend to have a later menopause than controls, the possibility cannot be excluded that breast cancer patients continue to have ovulatory cycles for a longer period during reproductive life. Such a finding--opposite to the working hypothesis--would complicate the interpretation of the results.

Adult↗
PubMed1988

A unifying concept of the aetiology of breast cancer.

A number of risk factors for breast cancer are considered jointly in one pathogenetic framework which relates to the formation of pre-cancerous lesions. Energy-rich diet during puberty and adolescence enhances the occurrence of pre-cancerous lesions in the breast. This process is counteracted by full-term pregnancies, and the earlier they come the fewer the number of such lesions. Energy-rich diet later in life contributes to the occurrence of obesity which, after menopause, enhances the growth of existing subclinical and clinical breast cancer. In both periods of life the nutritional factor exerts its effect through endocrine mechanisms in which oestrogens play a major part.

Age Factors↗
PubMed1988

Peptide and steroid hormones in subjects at different risk for diet-related diseases.

Populations eating low-fat or low-fat, high-fiber diets have lower mortality rates for many cancers and coronary heart disease. The importance of nutrient composition in the lumen on absorption and on function of the gastrointestinal tract as a factor in the development of these diseases has not been studied. We investigated the plasma levels of gut-CNS peptide hormones in lean and obese Dutch women fed a high-fat meal and administered cholecystokinin (CCK). After a high-fat meal the increase in plasma CCK was similar in lean and obese women. CCK administration significantly decreased insulin release in lean and obese women, decreased glucagon release in obese women, but caused a rapid increase in plasma glucagon in lean women. Although the CCK response was similar to a fat meal in lean and obese women, differences in the control of peptide hormone release occurred in response to fat meals and CCK administration.

Cholecystokinin↗
PubMed1987

Glucagon and insulin response to meals in non-obese and obese Dutch women.

Many digestive complaints are associated with abnormalities in gastrointestinal peptide hormone function. To investigate the effect of obesity on the release of pancreatic peptide hormones, we have compared the release of insulin and glucagon in non-obese-obese Dutch women in response to isocaloric mixed meals and to Naloxone, an opioid antagonist. Healthy premenopausal women who were separated into three groups based on body mass index (BMI less than 23; 23-27, greater than 28), were fed 600-calorie breakfasts. Higher fasting levels of plasma insulin and glucagon occurred in obese (BMI greater than 28) than lean (BMI less than 23) women, while glucagon and insulin release after a high fat meal occurred in obese women. Naloxone administration in obese women decreased plasma insulin and glucagon, but in lean women, naloxone increased plasma glucagon but did not alter plasma insulin levels. Results indicate differences in opiate effects on pancreatic function in non-obese-obese women.

Adult↗
PubMed1987

Selenium levels in nails of premenopausal breast cancer patients assessed prediagnostically in a cohort-nested case-referent study among women screened in the DOM project.

To determine the possible role of selenium in the pathogenesis of breast cancer, prediagnostic Se 77 m isotope levels in toenail clippings in premenopausal women were measured. The study was designed as a case-referent study nested in a cohort. Participants were recruited from the DOM-project breast-cancer screening cohorts. No decreased selenium levels were found up to two years prior to diagnosis, nor were Se levels different between prevalent and/or incident breast cancer cases, referents and women with benign breast disease. Se levels measured in nails could not detect women at higher risk for breast cancer. This study does not support the idea that Se supplementation could have a preventive potential for premenopausal breast cancer in women in the Netherlands.

Adult↗