Biomedical subjects

N Potischman

Publications and source records attributed to N Potischman.

48 records · Page 3Linked to original sources

PubMed1994

The relations between cervical cancer and serological markers of nutritional status.

We evaluated whether differences in serological nutrient indicators between cases and controls were likely to be due to different usual levels for cases or to altered metabolism due to disease. Blood samples obtained as part of a case-control study of invasive cervical cancer conducted in Latin America were evaluated for case-control differences and for trends with stage of disease. Serum alpha- and beta-carotene, cryptoxanthin, and alpha- and gamma-tocopherol showed no trend with extent of disease, although Stage IV cases had lower alpha- and beta-carotene values than did other cases. A slight trend of decreasing values with stage was observed for serum retinol, lycopene, and lutein. For cholesterol and triglyceride concentrations, an inverse trend was observed with stage of disease, which suggested a clinical effect of the disease on blood lipids. Adjustment for smoking, alcohol intake, or oral contraceptive use did not alter observed relations, nor was there evidence that the altered blood nutrient levels differed by histological type. These data suggest that serum values for some carotenoids from Stage I, II, and III cervical cancer are suitable for etiological studies, but spurious results may be obtained if late-stage cases are included. Evidence of trends with severity of disease for cholesterol and triglycerides, and possibly for retinol, lycopene, and lutein, suggest that special attention be given to disease effects of these nutrients in studies of cervical cancer.

Adult↗

PubMed1993

A population-based case-control study of dietary factors and endometrial cancer in Shanghai, People's Republic of China.

The relation between diet and endometrial cancer was examined in a population-based case-control study conducted in Shanghai, People's Republic of China, between 1988 and 1990, involving interviews with 268 cases and 268 controls aged 18-74 years. The subjects' usual dietary intake of 63 major foods during the previous 10 years (disregarding any recent changes) was measured by means of a structured quantitative food questionnaire. Although women in the highest quartile of total caloric intake had a 2.1-fold increased risk of endometrial cancer, risk varied according to the source of calories. The highest quartiles of caloric intake from fat and protein were associated with odds ratios of 3.9 and 3.1, respectively, while calories from carbohydrates, the major contributor of total calories in this population, were not related to risk. The association of fat and protein with endometrial cancer risk was confined to foods of animal origin in the diet. After adjustment for age, body mass index (weight (kg)/height (m)2), and number of pregnancies, odds ratios were 3.5 (95% confidence interval (CI) 2.0-6.0) and 3.0 (95% CI 1.7-5.1) for women in the highest quartiles of intake of animal fat and animal protein, respectively. Food group analyses showed a similar pattern, with high consumption of meat, eggs, and fresh fish being associated with elevated risks. After adjustment for total calories, no significant association of risk was found with intake of vegetables or dark green/yellow vegetables, or with estimated carotene intake, although fruit and allium vegetables were associated with some reduction in risk. These results suggest that diets rich in animal fat and animal protein may play an important role in the etiology of endometrial cancer.

Adolescent↗

PubMed1993

Dietary associations in a case-control study of endometrial cancer.

Despite the established role of obesity in the etiology of endometrial cancer, limited data are available from analytical epidemiologic studies on the association of risk with dietary factors. A case-control study of 399 cases and 296 controls conducted in five areas of the United States from 1 June 1987 to 15 May 1990, enabled evaluation of risk related to dietary intakes adjusted for potential confounders. Caloric intake was associated modestly with increased risk (odds ratio [OR] = 1.5, 95 percent confidence interval [CI] = 0.9-2.5 for highest cf lowest quartiles of intake), with the principal contributors being fat and protein calories. After adjustment for other risk factors, including body mass, increased risk was associated with higher intakes of fat. Several components of fat investigated were associated with increased risk, although associations were slightly stronger for saturated fat (OR = 2.1, CI = 1.2-3.7) and oleic acid (OR = 2.2, CI = 1.2-4.0) than for linoleic acid (OR = 1.6, CI = 0.9-2.8). Food-group analyses showed intake of complex carbohydrates--and specifically of breads and cereals--associated with reduced risks (OR = 0.6, CI = 0.4-1.1), whereas animal fat and fried foods were associated with elevated risks (OR = 1.5 and 1.7, respectively). The relations of endometrial cancer with animal fat and complex carbohydrates were independent. No consistent associations were noted for intakes of cholesterol, fiber, vitamins A and C, individual carotenoids, or folate-rich foods. These data imply an etiologic role for a diet rich in total fat and/or animal fat and low in complex carbohydrates with endometrial cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Body Mass Index↗

PubMed1993

Nutritional epidemiology of cervical neoplasia.

There appears to be a natural progression of some preinvasive cervical lesions to more advanced lesions. Although research has evaluated the associations between nutrients and particular preinvasive lesions or invasive disease, little work has been done to compare results across the spectrum of lesions in the progression to invasive disease. This review compiles studies that have evaluated the relation between nutrients and cervical neoplasia and evaluates the general consistency of the literature across stage of disease. Preformed vitamin A does not appear to be related to risk of any preinvasive or invasive lesions, whereas vitamin C has been associated with a reduced risk for dysplasia, in situ cancer, and invasive disease, particularly among smokers. There was evidence of reduced risks associated with various carotenoids and vitamin E at all stages of the disease process, although these studies were inconsistent and further work is needed. Folate was the only nutrient that appeared to be protective for dysplastic lesions and not related to risk of in situ or invasive disease. Red blood cell folate was a better predictor of dysplasia than were serum or dietary folate, and further investigation using this marker of folate status is warranted. Research is needed across a spectrum of lesions within one study, with particular attention to interactions between nutrients and other risk factors for disease.

Ascorbic Acid↗

PubMed1991

A case-control study of nutrient status and invasive cervical cancer. I. Dietary indicators.

A study of 748 cases and 1,411 hospital and community controls in four Latin American countries evaluated the association between certain elements of diet and invasive cervical cancer. Subjects were interviewed about their adult consumption of 58 food items, including the major sources of putative protective agents (vitamin A, carotenoids, vitamin C, and folacin) as well as other behavioral and medical characteristics related to cervical cancer. Participation rates were above 95% for both cases and controls. After adjustment for age, study site, sexual and reproductive behavior, socioeconomic status, screening practices, and detection of human papillomavirus 16/18 by filter in situ hybridization, a slightly lower risk was observed for the highest quartiles of consumption of fruit and fruit juices, while no reductions in risk were associated with vegetables, foods of animal origin, complex carbohydrates, legumes, or folacin-rich foods. When nutrient indices were derived, significant trends of decreasing risk were observed for vitamin C (adjusted odds ratio (OR) = 0.69 for the highest vs. the lowest quartile; p for trend = 0.003), beta-carotene (OR = 0.68; p = 0.02), and other carotenoids (OR = 0.61; p = 0.003). Inclusion of vitamin C and beta-carotene in the same model attenuated the association with beta-carotene, while the association with vitamin C remained unchanged. The results are consistent with those of other investigations and provide support for a protective effect of vitamin C, carotenoids, and other substances found in the same fruits and vegetables against the development of invasive cervical cancer. However, the fact that the associations were driven by relation in two of the study sites and among women of higher socioeconomic status leaves open the possibility of selection bias or effects of unidentified aspects of dietary patterns.

Ascorbic Acid↗

PubMed1991

A case-control study of nutrient status and invasive cervical cancer. II. Serologic indicators.

A study of 387 cases and 670 controls from four Latin American countries evaluated the hypothesis that lower serum levels of eight micronutrients were associated with a higher risk of invasive cervical cancer. The serologic analyses were restricted to a sample of subjects with stage I and II disease to minimize effects of the disease on the serologic markers. Ninety-four percent of eligible subjects donated blood samples, which were analyzed for carotenoids, retinol, and tocopherols by high-pressure liquid chromatography. Cases did not differ significantly from controls in mean serum levels of retinol, cryptoxanthin, lycopene, alpha-carotene, lutein, or alpha-tocopherol. The mean level of beta-carotene was lower and the mean level of gamma-tocopherol was higher among cases as compared with controls. After adjustment for age, study site, sexual and reproductive behavior, socioeconomic status, screening practices, detection of human papillomavirus types 16/18, cholesterol, and triglycerides, a trend of decreasing risk was associated with higher levels of beta-carotene (p for trend = 0.05), with the adjusted odds ratio decreasing to 0.72 for the highest versus the lowest quartile. beta-Carotene results were similar by stage of disease, which argues against an effect of disease progression on nutrient values. Unexpectedly, increasing risks were observed as the level of gamma-tocopherol increased (odds ratio = 2.09; p for trend = 0.03); however, levels were higher among stage II cases as compared with stage I cases, suggesting a metabolic alteration resulting from the disease process. The concordance in the strength and direction of the blood and dietary results, presented in the accompanying report (Herrero R, Potischman N, Brinton LA, et al., American Journal of Epidemiology 1991;134:1335-46), supports a role for beta-carotene or foods rich in beta-carotene in the etiology of cervical cancer. This study also indicates that simultaneous analysis using serologic and dietary nutrient indicators allows better discrimination of the association.

Carcinoma, Squamous Cell↗

PubMed1991

A case-control study of serum folate levels and invasive cervical cancer.

Although small intervention trials have suggested that folate supplementation reduces cervical dysplasia, the association of blood folate concentrations with invasive cervical cancer risk has not been investigated in well-controlled epidemiological studies. A study was conducted with newly diagnosed Stage I and II invasive cervical cancer cases and controls in 4 Latin American countries. Ninety-five% of subjects donated blood samples, resulting in 330 case and 565 control serum samples analyzed for folate concentrations by radioassay. Cases did not differ significantly from controls in mean levels of folate (5.00 and 4.90 ng/ml, respectively). No associations were observed between quartiles of serum folate and risk of cervical cancer after adjustment for other risk factors, and no interactions with established risk factors were observed. Folate levels were also unrelated to risk among women who might have compromised folate status because of recent or extended oral contraceptive usage or multiple pregnancies. Further, mean levels of folate were similar by stage of disease, arguing against an effect of disease progression on serum values. These results do not support a role for serum folate in the etiology of invasive cervical cancer.

Adenocarcinoma↗

PubMed1991

Associations between breast cancer, plasma triglycerides, and cholesterol.

A case-control study investigating the association between plasma lipids and breast cancer was conducted among women aged 30-80 in Buffalo, NY. All eligible women from a large breast clinic and two area physicians' offices were requested to participate over a one-year period. Subjects completed a health questionnaire and donated a fasting blood sample prior to diagnostic breast biopsies. The 83 women found to have breast cancer (cases) had significantly higher plasma triglyceride values than did the 113 women found not to have breast cancer (controls). Lower plasma beta-carotene values were associated with breast cancer, but only in those women with elevated triglyceride or cholesterol. Plasma cholesterol values were lower in those breast cancer cases presenting with more advanced stages of cancer, suggesting that metabolic effects of clinical and preclinical breast cancer may lower cholesterol levels. Although the limitations of case-control studies are well-recognized, these data suggest an etiologic role for plasma triglycerides and beta-carotene or for related dietary factors.

Adult↗

PubMed1990

Breast cancer and dietary and plasma concentrations of carotenoids and vitamin A.

A case-control study of breast cancer was conducted in Buffalo. Participants completed a food frequency questionnaire and donated a fasting blood sample before definitive workup for breast masses. Dietary and plasma concentrations of carotenoids and retinol for 83 women found to have breast cancer were compared with those of 113 women found to be free of breast cancer (control subjects). There were no case-control differences in dietary estimates of vitamin A intake or in plasma alpha-carotene and lycopene. However, subjects with breast cancer had lower concentrations of plasma beta-carotene than did control subjects (P = 0.02). There was no overall association between plasma retinol and breast cancer but a positive relationship was observed between retinol and breast cancer in the subgroup with low beta-carotene values. These results suggest that low plasma beta-carotene is associated with increased risk of breast cancer. Other studies will need to determine whether low carotene concentrations are a subtle effect of the disease or might be causally related to breast cancer.

Adult↗

PubMedDate not supplied

Effects of breast cancer treatments on plasma nutrient levels: implications for epidemiological studies.

The interpretation of case-control studies in which blood nutrient levels are examined as etiological factors in cancer is complicated by the possibility that either the disease or its treatment may alter these levels. Circulating levels of selected nutrients were examined prior to diagnostic biopsy and compared with levels 3 to 4 months after diagnosis among 71 women with breast cancer and 95 women with benign breast disease. Among women with benign breast disease or women with breast cancer who were not given postsurgical adjuvant drug therapy, levels of alpha-carotene, lycopene, alpha-tocopherol, cholesterol, and triglycerides did not change over time. In contrast, women who received chemotherapy had increased levels of cholesterol, retinol, and alpha- and gamma-tocopherol, and women on antiestrogen therapy showed increased levels of triglycerides and alpha-tocopherol. Overall, the concentrations of carotenoids (lycopene, alpha-carotene, and beta-carotene) did not change in breast cancer cases, although subgroup analyses showed increased levels of beta-carotene among cases not receiving drug treatment and decreased levels among those receiving antiestrogens. In summary, blood levels of some nutrients did not appear to be affected by breast cancer or its treatments, but changes were noted for levels of plasma lipids, tocopherols, retinol, and beta-carotene. Those investigating the etiological relationship between breast cancer and circulating nutrients need to consider these effects in designing and interpreting epidemiological studies.

Adult↗

PubMedDate not supplied

Endometrial cancer risk in relation to serum lipids and lipoprotein levels.

Blood lipids are useful biochemical indicators for assessing the risk of a number of chronic diseases, particularly those associated with obesity. In a multicenter case-control study that included 256 cases and 185 controls less than 75 years old, we studied the risk of endometrial cancer in relation to serum cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and triglycerides. Contrary to expectation, blood lipids were, in general, lower among cases compared with controls. The effects of low blood lipids, specifically cholesterol and low density lipoprotein cholesterol, were limited to older women (> or = 55 years). Risk of the disease in this subgroup of 177 cases and 110 controls was increased 3-4-fold among those with the lowest cholesterol or low density lipoprotein cholesterol values. For example, after adjustment for age, education, smoking status, obesity, and body fat distribution, the relative risks of endometrial cancer across decreasing quartiles of serum cholesterol were 1.0, 2.5, 2.4, and 4.2 (P for trend < 0.01). We examined blood lipid levels by disease stage. The low lipid values of older cases did not appear to be a consequence of the disease. While we cannot rule out the possibility that hypocholesterolemia is a predisposing factor for endometrial cancer, there is no obvious biological explanation for the inverse association.

Adult↗

PubMedDate not supplied

Relation of endometrial cancer risk to past and contemporary body size and body fat distribution.

In a multicenter case-control study that included 403 cases and 297 controls, we examined the relation of past and contemporary body size, including body fat distribution, to the risk of endometrial cancer. The relative contributions of past and contemporary body size were assessed by examining weight and height histories provided by the subjects. Anthropometric indicators thought to reflect early environmental influences (e.g., height and sitting height), current weight, and fat distribution patterns were measured directly. Height was not a risk factor for endometrial cancer, but inexplicably, sitting height was inversely associated with risk. Weight during early adulthood appeared to be directly related to disease risk, but the association was explained by contemporary weight and thus weight gain during adulthood. While contemporary weight was associated with risk of endometrial cancer, the effect was restricted to those in the top quartile. Women whose measured weight at interview exceeded 78 kg had 2.3 times the risk of those weighing less than 58 kg (95% confidence interval, 1.4 to 3.7). Upper-body obesity (waist-to-thigh circumference ratio) was a risk factor independent of body weight. After adjustment for weight, the relative risks of endometrial cancer across increasing quartiles of upper-body obesity were 1.0, 1.5, 1.8, and 2.6 (P for trend < 0.001). These data indicate that both obesity and the distribution of adipose tissue accumulated during adult life increase endometrial cancer risk substantially.

Adipose Tissue↗