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Biomedical subjects

J S Mandel

Publications and source records attributed to J S Mandel.

At least 55 records · Page 3Linked to original sources

Mortality associated with low plasma concentration of beta carotene and the effect of oral supplementation.

OBJECTIVE: To examine the relationship between beta carotene plasma concentration and beta carotene supplementation and risk of death from major disease causes. DESIGN: Cohort study of plasma concentrations; randomized, controlled clinical trial of supplementation. SETTING: Medical school-affiliated dermatology practices. PATIENTS: A total of 1188 men and 532 women with mean age of 63.2 years, who had enrolled in a randomized clinical trial of beta carotene supplementation to prevent nonmelanoma skin cancer. INTERVENTION: Oral beta carotene, 50 mg per day for a median of 4.3 years. MAIN OUTCOME MEASURES: All-cause mortality and mortality from cardiovascular disease and cancer. RESULTS: During a median follow-up period of 8.2 years, there were 285 deaths. Persons whose initial plasma beta carotene concentrations were in the highest quartile (>0.52 micromol/L [27.7 microg/dL]) had a lower risk of death from all causes (adjusted relative rate [RR], 0.52; 95% confidence interval [CI] 0.44 to 0.87) and from cardiovascular diseases (adjusted RR, 0.57; 95% CI, 0.34 to 0.95) compared with persons with initial concentrations in the lowest quartile (<0.21 micromol/L [11.2 microg/dL]). Patients randomly assigned to beta carotene supplementation showed no reduction in relative mortality rates from all causes (adjusted RR, 1.03; 95% CI, 0.82 to 1.30) or from cardiovascular disease (adjusted RR, 1.16; 95% CI, 0.82 to 1.64). There was no evidence of lower mortality following supplementation among patients with initial beta carotene concentrations below the median for the study group. CONCLUSIONS: These analyses provide no support for a strong effect of supplemental beta carotene in reducing mortality from cardiovascular disease or other causes. Although the possibility exists that beta carotene supplementation produces benefits that are too small or too delayed to have been detected in this study, noncausal explanations should be sought for the association between plasma concentrations of beta carotene and diminished risk of death.

Administration, Oral↗

International renal cell cancer study. VII. Role of diet.

We investigated the role of diet in the etiology of renal cell cancer (RCC) in a multi-center, population-based case-control study conducted in Australia, Denmark, Sweden and the United States, using a shared protocol. A total of 1,185 incident histopathologically confirmed cases (698 men, 487 women) and 1,526 controls (915 men, 611 women) frequency-matched to cases by sex and age were included in the analyses. The association between RCC and diet was estimated by relative risks (RR) and 95% confidence intervals (CI) adjusted for age, sex, study center, body mass index and smoking. A statistically significant positive association was observed for total energy intake (RR = 1.7, 95% CI = 1.4-2.2 for the highest vs. lowest quartile, p value for trend < 0.00001), while the hypothesis that protein and fat are risk factors independent of energy was not supported. Fried meats were associated with increased RCC risk, while vegetables and fruits were protective, with the strongest effect observed for the highest quartile of consumption of orange/dark green vegetables but not vitamin C or beta carotene. Increased risk was associated with low intake (lowest decile) of vitamin E and magnesium. We observed an apparent protective effect of alcohol confined to women and probably due to chance. Our findings indicate an important role of nutrition in the development of RCC. The apparent positive association of energy intake with risk of RCC needs further investigation in a prospective cohort study to exclude the possible impact of differences in recall between cases and controls.

Adult↗

Serum perfluorooctanoic acid and hepatic enzymes, lipoproteins, and cholesterol: a study of occupationally exposed men.

Perfluorooctanoic acid (PFOA) produces marked hepatic effects, including hepatomegaly, focal hepatocyte necrosis, hypolipidemia, and alteration of hepatic lipid metabolism in a number of animal species. In rodents, PFOA is a peroxisome proliferator, an inducer of members of the cytochrome P450 superfamily and other enzymes involved in xenobiotic metabolism, an uncoupler of oxidative phosphorylation, and may not be a cancer promoter. Although PFOA is the major organofluorine compound found in humans, little information is available concerning human responses to PFOA exposure. This study of 115 occupationally exposed workers examined the cross-sectional associations between PFOA and hepatic enzymes, lipoproteins, and cholesterol. The findings indicate that there is no significant clinical hepatic toxicity at the PFOA levels observed in this study. PFOA may modulate the previously described hepatic responses to obesity and xenobiotics.

Adult↗

Mammogram utilization among farm women.

Utilization of preventive health care services is lower in rural populations than in urban populations, possibly as a result of barriers to preventive health care that are characteristic of rural settings. This study was conducted to identify factors associated with mammogram utilization among farm women. Mammogram utilization among farm women from six southern Minnesota counties was examined as part of a larger community-based cancer intervention study. Farm women aged 40 and older were randomly selected from a list of farm households and interviewed by telephone to determine mammogram utilization and factors related to utilization. Of the 606 respondents, 78 percent reported ever having a mammogram and 49 percent reported a mammogram within the past year. Physician recommendation for a screening mammogram and family history of breast cancer were found to be associated with ever having a mammogram. Correct knowledge of mammogram screening guidelines was associated with a mammogram within the past 12 months. Overall, physician recommendation was the most influential determinant of utilization. As more emphasis is placed on prevention, patient education by physicians can have the greatest impact on mammogram utilization.

Agriculture↗

Factors associated with safe use of agricultural pesticides in Minnesota.

How farmers protect themselves against pesticide exposure has important public health consequences. To obtain insights into pesticide self-protection, this study obtained data on chemically resistant glove and other protective equipment use as they relate to the type of farming practice, demographic characteristics of farmers and their farming operations, farmers' preventive health beliefs and behaviors, and factors related to their health care. Data were obtained by telephone interviews conducted in six rural Minnesota counties. Survey respondents totaled 1, 327 (87% response rate), with 502 reporting pesticide use. Ninety-five percent of the latter respondents believed in the effectiveness of protective equipment and 88 percent believed that pesticide exposures are harmful. Fifty-six percent of the subjects wore chemically resistant gloves and 22 percent wore other protective clothing 75 percent of the time or more when using pesticides. Glove use and certification to use restricted pesticides was less frequent for women. The use of protective equipment in this group of Minnesota farmers was weakly related to being certified to apply restricted pesticides, believing in the effectiveness of protective clothing, believing that smoking causes serious health problems, using crop insecticides, and distance to a health care facility.

Agriculture↗

Obesity and risk of renal cell cancer.

In a population-based case-control study including 449 directly interviewed cases and 707 controls, we assessed the risk of renal cell cancer associated with height, weight, body mass index (BMI), and frequency of weight changes. Odds ratios and 95% confidence intervals were estimated by using logistic regression models. Among women, risk increased with increasing usual BMI (P for trend < 0.001). A nearly 4-fold risk was found among the 10% of women with the highest usual BMI (odds ratio = 3.8; confidence interval = 1.7-8.4). Among men, no clear trend was observed with usual weight or BMI, although the highest risk (30-50%) generally was seen among those in the upper deciles of weight or BMI. There was no clear indication that excess BMI early or late in life disproportionately affected risks. Risk also was not related to patterns of weight fluctuations or use of diet pills. Our study supports previous observations linking renal cell cancer risk to increased BMI among women and suggests a weaker association in men. Given the increasing prevalence of obesity and the rising incidence of renal cell cancer in the United States, additional studies are needed to disentangle the effects of BMI from various correlates and to identify the mechanisms by which obesity affects risk.

Adult↗

International renal-cell cancer study. VIII. Role of diuretics, other anti-hypertensive medications and hypertension.

Risk of renal-cell cancer in relation to use of diuretics, other anti-hypertensive medications and hypertension was assessed in a multi-center, population-based, case-control study conducted in Australia, Denmark, Germany, Sweden and the United States, using a shared protocol and questionnaire. A total of 1,732 histologically confirmed cases and 2,309 controls, frequency-matched to cases by age and sex, were interviewed. The association between renal-cell cancer and the drugs was estimated by relative risks (RRs) and 95% confidence intervals (CIs). Risks were increased among users of diuretics and other anti-hypertensive medications. After adjustment for hypertension, risk for diuretics was reduced to unity, except among long-term (15+ years) users. Risk for use of non-diuretic anti-hypertensive drugs remained significantly elevated and increased further with duration of use. Overall risk was not enhanced when both classes of medications were used. Excess risk was not restricted to any specific type of diuretic or anti-hypertensive drug and no trend was observed with estimated lifetime consumption of any particular type of product. The RR for hypertension after adjustment for diuretics and other anti-hypertensive medications was 1.4 (95% CI = 1.2-1.7), although among non-users of any anti-hypertensive medications, there was little excess risk associated with a history of hypertension. Exclusion of drug use that first occurred within 5 years of cancer diagnosis or interview did not alter the associations. Our findings suggest small effects on renal-cell cancer risk associated with hypertension and use of diuretics and other anti-hypertensive medications. However, because of potential misclassifications of these highly correlated variables, it is difficult to distinguish the effect of treatment from its indication, hypertension.

Antihypertensive Agents↗

Breast cancer among radiologic technologists.

OBJECTIVE: To evaluate the risk of breast cancer among women occupationally exposed to ionizing radiation. DESIGN: Case-control study. PARTICIPANTS: A health survey of 105,385 women radiologic technologists certified by the American Registry of Radiologic Technologists since 1926. Among 79,016 respondents, 600 breast cancer cases were identified. Each of 528 eligible subjects with breast cancer was matched to five control subjects based on age, year of certification, and follow-up time. MAIN OUTCOME MEASURES: Relative risk (RR) estimated as the relative odds ratio for breast cancer over categories of years worked as a radiologic technologist and according to personal and occupational exposure characteristics. RESULTS: Study subjects had been certified for a mean of 29 years; 63.8% of cases and 62.6% of controls worked as radiologic technologists for 10 years or more. Significant increased risks for breast cancer were associated with early age at menarche (for < 11 years of age: RR = 1.79; 95% confidence interval [CI], 1.09 to 2.94), nulliparity (RR = 1.36; 95% CI, 1.04 to 1.78), first-degree relative with history of breast cancer (RR = 2.07; 95% CI, 1.56 to 2.74), prior breast biopsy (RR = 1.53; 95% CI, 1.17 to 2.00), alcohol consumption (for > 14 alcoholic drinks per week: RR = 2.12; 95% CI, 1.06 to 4.27), thyroid cancer (RR = 5.36; 95% CI, 1.64 to 17.5), hyperthyroidism (RR = 1.66; 95% CI, 1.02 to 2.71), and residence in the northeastern United States (RR = 1.66; 95% CI, 1.19 to 2.30). Jobs involving radiotherapy, radioisotopes, or fluoroscopic equipment, however, were not linked to breast cancer risk, nor were personal exposures to fluoroscopy or multifilm procedures. Use of birth control pills, postmenopausal estrogens, or permanent hair dyes also were not risk factors. Based on dosimetry records for 35% of study subjects, cumulative exposures appeared low. Among women who worked more than 20 years, the RR for breast cancer was 1.13 (95% CI, 0.79 to 1.64). CONCLUSIONS: More than 50% of the reported breast cancers could be explained by established risk factors. Employment as a radiologic technologist, however, was not found to increase the risk of breast cancer. The contribution of prolonged exposure to relatively low doses of ionizing radiation to breast cancer risk was too small to be detectable at this time.

Adult↗

Longitudinal compliance with annual screening for fecal occult blood. Minnesota Colon Cancer Control Study.

In a randomized, controlled trial of fecal occult blood screening for colorectal cancer, the Minnesota Colon Cancer Control Study carried out 11 annual mail screens in two phases between 1976 and 1992. This long-term compliance record of 15,476 individuals is summarized and related to demographic characteristics as well as to the screening experience of the participants. There was a strong and consistent effect of age, with peak compliance among participants about 70 years old, and lower compliance among the youngest (< or = 55 years) and oldest (> or = 80 years) participants. There was a significantly higher rate of screen compliance among participants who lived with other participants, compared with households where only one individual participated in the study. Finally, participants who underwent a diagnostic colorectal examination with negative results had significantly lower odds of compliance.

Aged↗

International renal-cell cancer study. IV. Occupation.

The relationship between renal-cell cancer (RCC) and occupation was investigated in an international multicenter population-based case-control study. Study centers in Australia, Denmark, Germany, Sweden and the United States interviewed 1732 incident RCC cases and 2309 controls. Significant associations were found with employment in the blast-furnace or the coke-oven industry [relative risk (RR), 1.7; 95% confidence interval (CI), 1.1-2.7], the iron and steel industry (RR, 1.6; 95% CI, 1.2-2.2) and exposure to asbestos (RR, 1.4; 95% CI, 1.1-1.8), cadmium (RR, 2.0; 95% CI, 1.0-3.9), dry-cleaning solvents (RR, 1.4; 95% CI, 1.1-1.7), gasoline (RR, 1.6; 95% CI, 1.2-2.0) and other petroleum products (RR, 1.6; 95% CI, 1.3-2.1). Asbestos, petroleum products and dry-cleaning solvents appear to merit further investigation, in view of the relationship between risk and duration of employment or exposure and after adjustment for confounding. There was a negative association between RCC and education, but it was not consistent across all centers. Overall, the results of our multicenter case-control study suggest that occupation may be more important in the etiology of RCC than indicated by earlier studies.

Aged↗

International renal-cell cancer study. V. Reproductive factors, gynecologic operations and exogenous hormones.

The relationships between reproductive factors, exogenous hormones and renal-cell cancer were examined in an international, multicenter, population-based, case-control study undertaken in 1989-1991. Data from 5 centers situated in Australia, Denmark, Germany, Sweden and the United States included for analysis 608 women with renal-cell cancer and 766 female controls. A significant trend in risk (p = 0.002) was associated with number of births, with an 80% excess risk for 6 or more births [RR = 1.8, 95% confidence interval (CI) = 1.1 to 2.9] compared with one birth. A decreasing risk was seen for increasing age at first birth, although this was confounded by body-mass index and number of births. A suggestive reduction of risk was also seen for increasing age at menarche. Age at menopause was unrelated to risk of renal-cell cancer. An increased risk was observed for women having had both a hysterectomy and an oophorectomy. Use of oral contraceptives in non-smoking women reduced the risk of renal-cell cancer (RR = 0.5, 95% CI = 0.4 to 0.8); this reduction increased with longer duration of use. No association was observed for estrogen replacement therapy. Our results indicate that certain hormonal and reproductive variables may be related to risk of renal-cell cancer and deserve further investigation, both epidemiologically and experimentally.

Adult↗

Reproductive factors and the risk of renal cell cancer among women.

In etiologic studies of renal cell carcinoma the role of reproductive variables and the use of exogenous hormones have not been well examined. In a population-based case-control study including 165 female cases and 227 controls, we assessed the risk of renal cell cancer associated with reproductive factors and use of oral contraceptives and menopausal hormones. Odds ratios were computed using logistic regression analyses. Risk was positively associated with number of births and inversely associated with age at first birth, with the largest increases in risk (more than 2-fold) among women with 5 or more births after age 25. After adjustment for age, smoking status, body mass index and age at first birth, women with 5 or more births had a 2-fold risk (OR = 2.2, 95% CI = 1.2-4.0) relative to those with 1 or 2 births. Age at first birth, however, was no longer a risk factor when the number of births was adjusted for. The association with parity was considerably stronger among women with a history of hypertension or above-median body mass index than among those without these conditions. In addition, risk was reduced among long-term oral contraceptive users but elevated among women who had had a hysterectomy or used menopausal hormones. Our findings suggest that reproductive factors, particularly the number of births, may play an etiologic role in renal cell cancer among women and deserve further study.

Adult↗

International renal-cell cancer study. II. Analgesics.

There has been concern about the role of analgesics in the development of renal-cell cancer, although a few studies have reported moderately elevated risks with regular or long-term use. In a large international case-control study of renal-cell cancer we examined, among other hypotheses, the effect of phenacetin-containing and of other types of analgesics: paracetamol (acetaminophen), salicylates (mainly aspirin) and pyrazolones (e.g., antipyrine or phenazone). Relative risks, adjusted for the effects of age, sex, body-mass index, tobacco smoking and study centre, were not significantly increased with intake of phenacetin, either when lifetime consumption was categorized at the level of > or = 0.1 kg or when subjects were subdivided further by amount. Nor were paracetamol, salicylates or pyrazolones linked with renal-cell cancer. No consistently increasing risks with consumption level was found. The lack of association was not altered by restricting analgesic use to that which occurred 5 or 10 years before the defined "cut-off" date or when analysis was restricted to exclusive users of a particular type of analgesic. Neither was the risk influenced by the rate of consumption or whether the consumption had occurred at a young age. Our study provides clear evidence that aspirin is unrelated to renal-cell cancer risk, and our findings do not support the hypothesis that analgesics containing phenacetin or paracetamol increase the risk, although the number of "regular" users and the amount of these types of analgesic consumed were too small to confidently rule out a minor carcinogenic effect of phenacetin and paracetamol.

Acetaminophen↗

International renal-cell cancer study. III. Role of weight, height, physical activity, and use of amphetamines.

Although numerous studies have identified obesity or high relative weight as a risk factor for renal-cell cancer in women, the degree to which this effect is present in men remains unclear. A multicenter population-based case-control study concerning incident cases of histologically verified renal-cell cancer (n = 1,732) and age- and sex-matched controls (n = 2,309) was conducted in Australia, Denmark, Germany (2 centers), Sweden and the United States. Relative weight was estimated by the body mass index, and the association between this factor and other factors, such as height, physical activity and use of amphetamines, was measured by the relative risk estimated in logistic regression models. Body mass index was found to be a risk factor among women and, to a lesser extent, among men. A 3-fold increased risk (RR = 3.6, 95% CI = 2.3-5.7) was observed for women with a relative weight in the top 5% compared with those in the lowest quartile. Rate of weight change (estimated as weight change per annum in kilograms) appeared to be an independent risk factor among women but not among men. Physical activity and height were unrelated to risk of renal-cell cancer regardless of level of BMI, while use of amphetamines was associated with an increased risk among men, although no dose or duration effect was seen. Our findings verify the link between high relative weight and risk of renal-cell cancer, particularly among women. The mechanism that underlies this association is, however, still unclear, although the rate of weight change may play a role.

Adult↗

International renal-cell cancer study. I. Tobacco use.

The relationship between renal-cell cancer (RCC) and tobacco use was investigated in an international, multicenter, population-based case-control study. Coordinated studies were conducted in Australia, Denmark, Germany, Sweden and the United States using a shared protocol and questionnaire. A total of 1,732 cases (1,050 men, 682 women) and 2,309 controls (1,429 men, 880 women) were interviewed for the study. No association was observed between risk and use of cigars, pipes or smokeless tobacco. A statistically significant association was observed for cigarette smoking, with current smokers having a 40% increase in risk [relative risk (RR) = 1.4, 95% confidence interval (CI) 1.2-1.7]. Risk increased with intensity (number of cigarettes) and duration (years smoked). Among current smokers the RR for pack-years rose from 1.1 (95% CI 0.8-1.5) for < 15.9 pack years to 2.0 (95% CI 1.6-2.7) for > 42 pack years (p for trend < 0.001). Long-term quitters (> 15 years) experienced a reduction in risk of about 15-25% relative to current smokers. Those who started smoking late (> 24 years of age) had about two-thirds the risk of those who started young (< or = 12 years of age). Overall, the findings of this pooled analysis confirm that cigarette smoking is a causal factor in the etiology of RCC.

Adult↗

Employment practices and breast cancer among radiologic technologists.

A case-control study of breast cancer and employment practices among female radiologic technologists was conducted. The cohort from which cases and controls were derived included over 105,000 female medical radiation workers certified by the American Registry of Radiologic Technologists during 1926-1980. Breast cancer cases (n = 528) were individually matched to an average of five control subjects (n = 2628) based on year of birth, year of certification, and length of follow-up. Procedures most commonly performed by controls included fluoroscopy (93%), portable radiographs (92%), routine radiographs (92%), multifilm procedures (87%), dental x-rays (46%), radium therapy (31%), orthovoltage (23%), and cobalt-60 (21%). Breast cancer was not significantly increased with occupational experience with any of these procedures. Furthermore, risk was not related to number of years worked with a particular procedure. This study is reassuring in indicating that medical radiation workers are not at substantial risk for developing radiation-induced breast cancer. However, because only surrogate measures of radiation exposure were available, possibility of a small risk cannot be discounted. Ongoing follow-up of this cohort for incident cancers will incorporate detailed exposure assessment schemes, providing additional information on effects of long-term low-dose radiation through occupation.

Adult↗

Risk of renal cell cancer in relation to diuretics, antihypertensive drugs, and hypertension.

Although recent data have suggested an association between renal cell cancer and the use of diuretics, it remains unclear whether these medications or hypertension is the important risk factor. In a population-based case-control study including 440 renal cell cancer cases, spouses of an additional 151 cases, and 691 controls, we assessed renal cell cancer risk associated with hypertension and use of diuretics and other antihypertensive medications. Risks increased with the use of diuretics or other drugs that lower blood pressure, especially among persons who reported no history of hypertension. After adjustment for hypertension, the use of diuretics alone was associated with a 40% excess risk (OR = 1.4; 95% CI = 0.8-2.2), while use of other antihypertensive drugs was linked to a 2-fold risk (OR = 2.0; 95% CI = 1.2-3.3). The excess risk was not restricted to any specific products, and no trend was observed with estimated lifetime consumption of any product. Furthermore, risk was not potentiated by the presence of both hypertension and the use of antihypertensive drugs. Among persons who did not use antihypertensive drugs, a history of hypertension was associated with a significant 40-50% excess risk of renal cell cancer. Excluding subjects with hypertension diagnosed within 5 years of cancer diagnosis or interview had only a small effect on risk. These findings suggest small effects on renal cell cancer risk associated with hypertensive disease and with the use of diuretics and other antihypertensive drugs, but it is difficult to disentangle the separate effects due to potential misclassification of highly correlated events.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗