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Biomedical subjects

D W Kaufman

Publications and source records attributed to D W Kaufman.

At least 55 records · Page 3Linked to original sources

Tar content of cigarettes in relation to lung cancer.

Although it is generally considered established that the risk of lung cancer is directly related to the tar content of cigarettes, an examination of the results of previous studies does not yield conclusive evidence in favor of the hypothesis. The authors evaluated this issue in a study of 881 cases of lung cancer and 2,570 hospital controls who were 40 to 69 years of age; data were collected by interview in hospitals in the United States and Canada from November 1981 to June 1986. For each year of smoking, cigarette brands were classified according to their tar content as published in regular Federal Trade Commission reports (from 1967 to 1985) or the Reader's Digest (from 1957 to 1966). Tar values for years for which there was no published information were estimated by interpolation. Smokers were divided, according to the tar content of their cigarette brands averaged over a specified period, into low (less than 22 mg/cigarette), medium (22-28 mg/cigarette), and high (greater than or equal to 29 mg/cigarette) tar smokers. When the average tar content was based on cigarettes smoked at least 10 years previously, the relative risk estimates for medium and high tar smokers compared with low tar smokers were 3.0 and 4.0 after control for potentially confounding factors, including the number of cigarettes smoked per day. The trend was significant (p = 0.002). The tendency for the risk of lung cancer to increase with increasing tar content was consistent among men and women. The results provide further support for the hypothesis that the tar content of cigarettes is directly related to lung cancer risk. However, the data were limited in that there were very few subjects whose lifetime tar exposure averaged less than 10 mg/cigarette.

Adult↗

Oral contraceptive use and liver cancer.

The risk of liver cancer in relation to use of oral contraceptives was evaluated in a hospital-based case-control study conducted in five US cities from 1977 to 1985. Twelve new cases of liver cancer were identified in women aged 19-54 years; five controls selected from among patients hospitalized for acute conditions unrelated to oral contraceptive use were matched to each case on age (five-year categories), date of interview (three-year categories), and geographic location of the hospital. Among nine cases classified as having hepatocellular carcinoma, eight (89%) had used oral contraceptives; only 16 (36%) of 45 matched controls had used oral contraceptives. Among three other cases (two with cholangiocarcinomas and one with liver cancer of undetermined type), all had used oral contraceptives, compared with four of 15 matched controls. The results confirm the strong positive association between oral contraceptive use and hepatocellular carcinoma observed in earlier studies. Such an association is consistent with evidence that oral contraceptive use is associated with benign hepatic tumors in young women. However, the number of cases of liver cancer in the United States that are attributable to oral contraceptive use is probably small, because liver cancer is extremely rare in the United States.

Adenoma, Bile Duct↗

The risks of cancers of the colon and rectum in relation to coffee consumption.

To assess whether recent coffee consumption is related to the incidence of large bowel cancer, the authors analyzed data from a multipurpose hospital-based case-control study of several cancers, conducted from 1978 to 1986 in Boston, Massachusetts, New York, New York, Philadelphia, Pennsylvania, and Baltimore, Maryland: 717 cases of colon cancer and 538 cases of rectal cancer were compared with 3,883 controls admitted for nonmalignant and malignant illnesses unrelated to coffee use. Relative risks were estimated by multiple logistic regression with allowance for age, sex, cigarette smoking, alcohol consumption, and several other potential confounding factors. Overall, relative to the consumption of one cup of coffee per day, the estimated relative risk of colon cancer for consumption of up to four cups per day in the period before admission was close to 1.0; for consumption of five or more cups per day, it was 0.6 (95% confidence interval 0.4-0.8). The results were consistent in men and women, and similar results were obtained whether the measure of consumption was use in the year before admission or use three years before admission. For rectal cancer, some relative risk estimates were elevated, particularly in men, but there was no consistent pattern of association, nor was there a trend of increasing risk with increasing consumption. The data suggest that recent coffee consumption is not related to an increased risks of large bowel cancer and that heavy coffee consumption may reduce the risk of colon cancer. A biologic rationale for such a reduction has not been established.

Adult↗

Noncontraceptive estrogen use and epithelial ovarian cancer.

The relation of noncontraceptive estrogen use to epithelial ovarian cancer was evaluated in a case-control study conducted in hospitals mainly in the northeastern United States. There were 377 cases diagnosed within the year before hospital admission and 2,030 hospital controls; data were collected by interview in the hospital. Compared with women who never took noncontraceptive estrogens, the overall relative risk estimate for women whose estrogen use lasted at least one year and was not combined with progestogens or testosterone was 1.2 (95% confidence interval (CI) 0.8-1.9), after taking into account risk factors for ovarian cancer. There were 55 cases of the endometrioid, clear cell, or malignant mixed mesodermal cell type; the corresponding relative risk estimate was 0.9 (95% CI 0.3-3.0). There were 26 cases of undifferentiated cell type, with a relative risk estimate of 3.6 (95% CI 1.2-11). Relative risk estimates were similar in a subset of the cases (57%) for which pathology slides were reviewed. For estrogen use of long duration, use of high-dose preparations, or use in the distant past, the relative risk estimates were not significantly different from 1.0. The estimates were elevated for some categories of use, but not consistently--for example, for an interval of 5-9 years since estrogen use began (relative risk (RR) = 2.7), but not after shorter or longer intervals, and for use of conjugated estrogens with a dose of 0.3 mg (RR = 3.2) or 1.25 mg (RR = 2.4), but not for doses of 0.625 mg or 2.5 mg. The relative risk estimate was also elevated for use by nulliparous women (RR = 2.4). The results suggest that, overall, noncontraceptive estrogen use is not associated with the risk of epithelial ovarian cancer. Furthermore, our data do not support the hypothesis that estrogens increase the risk of endometrioid ovarian cancer. The elevated estimates could be due to multiple stratification of the data, but they should be explored in further studies, given the lethality of ovarian cancer and the common use of estrogens by postmenopausal women.

Adult↗

Major upper gastrointestinal tract bleeding. Relation to the use of aspirin and other nonnarcotic analgesics.

In a hospital-based case-control study, the risk of a first episode of major upper gastrointestinal tract bleeding in subjects now known to be predisposed was assessed in relation to the use of nonnarcotic analgesics. For aspirin use within the week before the onset of symptoms, the rate ratio estimates, adjusted for potential confounding, were 15 (95% confidence interval, 6.4 to 34) for regular use (at least four days a week) and 5.6 (confidence interval, 2.7 to 12) for occasional use. For aspirin use discontinued at least one week earlier, the estimate was 1.6 (confidence interval, 0.6 to 4.2). There was no evidence that acetaminophen use increased the risk. For the regular use of other analgesics in the week before onset, the adjusted rate ratio estimate was 9.1 (confidence interval, 2.7 to 31); there were insufficient data to evaluate occasional use. The findings suggest that the risk of bleeding is increased substantially by aspirin, even when used occasionally. With the exception of acetaminophen, other nonnarcotic analgesics may also increase the risk, but they remain to be evaluated individually.

Acetaminophen↗

Breast cancer in relation to the occurrence and time of induced and spontaneous abortion.

The authors evaluated whether an induced or spontaneous abortion during the first six months of gestation, particularly if it occurs before the first term pregnancy, increases the risk of breast cancer. Data from a case-control study of women under 70 years of age were used: 3,200 cases of breast cancer were compared with 4,844 controls with nonmalignant nongynecologic conditions. Among both nulliparous and parous women, the risk of breast cancer was not related to the number of induced or spontaneous abortions. After allowance for all identified potential confounding factors, the estimated relative risk for nulliparous women with an induced abortion relative to those who had never been pregnant was 1.3 (95% confidence interval (CI) 0.8-2.2), and for spontaneous abortion, the corresponding estimate was 0.9 (95% CI 0.5-1.5). Among parous women, the estimated relative risks were 1.2 (95% CI 0.9-1.6) for an induced abortion and 0.9 (95% CI 0.8-1.0) for a spontaneous abortion, relative to never having had an abortion of any type. The time of the abortion had little effect: The relative risk estimates were 0.9 (95% CI 0.5-1.4) for induced abortion before the first term birth, 1.4 (95% CI 1.0-1.9) for induced abortion first occurring after the first term birth, 0.9 (95% CI 0.7-1.2) for spontaneous abortion before the first term birth, and 0.9 (95% CI 0.7-1.0) for spontaneous abortion first occurring after the first term birth. Similar results were evident for women under age 40, among whom the frequency of induced abortion was relatively high. These data suggest that the risk of breast cancer is not materially affected by abortion, regardless of whether it occurs before or after the first term birth.

Abortion, Induced↗

Coffee drinking and nonfatal myocardial infarction in men under 55 years of age.

The relation of coffee consumption to the risk of nonfatal first myocardial infarction in men under 55 years of age was assessed in a hospital-based case-control study conducted from 1980 to 1983 in hospitals in Massachusetts, Rhode Island, Connecticut, and New York: 1,873 men with first nonfatal myocardial infarctions were compared with 1,161 controls admitted for conditions unrelated to coffee ingestion. After allowance for major risk factors for myocardial infarction, the relative risk estimate for recent consumption of caffeine-containing coffee increased with increasing level of daily intake, from 1.4 for one to two cups per day to 1.6 for three to four cups, 1.8 for five to nine cups, and 2.9 for greater than or equal to 10 cups, relative to consumption of no coffee (p less than 0.001 for trend). The association was apparent in each age group and in both smokers and nonsmokers. For those who drank decaffeinated coffee only, on the basis of small numbers, there was a suggestion of an increased risk among men who had consumed at least five cups daily for less than five years but not among those who had drunk this amount for at least five years; whether the apparent association among the shorter-term drinkers was due to previous consumption of caffeine-containing coffee could not be determined. The findings suggest that caffeine-containing coffee increases the risk of myocardial infarction and that men who drink at least five cups daily may increase their risk by about twofold or more.

Adult↗

Comparisons of ruminal fermentation characteristics and microbial populations in bison and cattle.

Ruminal microbial populations, fermentation characteristics, digestibility, and liquid flow rates in two ruminally cannulated bison and two ruminally cannulated Hereford steers fed a prairie hay diet were compared. No significant differences in anaerobic bacterial counts, volatile fatty acid concentrations, or ruminal pHs were evident between bison and cattle. Also, no significant differences in neutral detergent fiber digestibility, indigestible fiber retention time, or intake were detected between bison and cattle, although cattle had higher levels (P less than 0.08) of ruminal dry matter and indigestible fiber than bison. Bison had a smaller (P = .02) ruminoreticular volume, faster liquid dilution rates, and faster liquid turnover times than cattle. The average ruminal ammonia nitrogen concentration was higher (P = 0.02) in bison (1.17 mg/dl) than in cattle (0.79 mg/dl). Total ciliate protozoal counts and cell volume were greater (P = 0.07) in bison (32.8 x 10(4)/g and 407.1 x 10(-4) ml/g, respectively) than in cattle (15.7 x 10(4)/g and 162.2 x 10(-4) ml/g, respectively). Bison harbored higher (P less than 0.02) numbers of Dasytricha spp., Eudiplodinium maggii, Eudiplodinium bursa, and Epidinium spp. than cattle and possessed a type B protozoan population. The cattle possessed a mixed type A-type B population that was characterized by Ophryoscolex spp. and Polyplastron spp. in association with low concentrations of Epidinium spp. and Eudiplodinium maggii.

Animal Feed↗

Cigar and pipe smoking and myocardial infarction in young men.

The effect of cigar and pipe smoking on the risk of myocardial infarction was evaluated in an interview study of 572 men with non-fatal first myocardial infarctions and 934 hospital controls. The study was conducted in the north eastern United States from 1980 to 1983. All subjects were 40-54 years of age, and none had smoked cigarettes for at least two years. Among men who had never smoked cigarettes the relative risk of myocardial infarction for those who smoked at least five cigars a day, compared with not smoking cigars and pipes and allowing for other risk factors, was estimated to be 1.7 (95% confidence interval 0.6 to 4.8). Among ex-smokers of cigarettes the corresponding estimate for those who smoked at least five cigars a day was 4.5 (2.2 to 9.2). The estimates for men who smoked fewer cigars, or pipes, were closer to 1.0 and not significant. Men who stop smoking cigarettes and switch to at least five cigars a day apparently continue to have an increased risk of myocardial infarction, possibly because they continue to inhale the smoke.

Adult↗

Epithelial ovarian cancer and coffee drinking.

A recent report from a case-control study in Greece suggested that coffee consumption is related to an increase in the risk of ovarian cancer. This hypothesis was examined in a hospital-based case-control study in the US. Information on coffee drinking and other factors was obtained from 290 incident cases of epithelial ovarian cancer and compared with that of 580 controls with non-malignant conditions of acute onset and 476 controls with cancer of other sites. Adjustment was made for the potential confounding effects of several factors, including the major known risk factors for ovarian cancer. The estimated relative risk for drinking five or more cups of coffee per day, relative to none, was 1.1 (95% confidence interval, 0.6-2.0) using the controls with non-malignant conditions and 1.0 (0.5-1.8) using the controls with cancer. The estimates for drinking less than five cups per day were greater than 1.0, but this could have been due to chance. The consumption of decaffeinated coffee and tea also appeared to have no influence on risk. The evidence from this study suggests that, if coffee drinking increases the risk of ovarian cancer, the effect is small.

Adult↗

Risk factors for breast cancer in black women.

Risk factors for breast cancer were examined in black women in a hospital-based case-control study of 529 black women with breast cancer and 589 controls. Late age at menarche was associated with a reduced risk of breast cancer. Women having 5 or more children had a reduced risk relative to that of women with fewer or no children. Late age at first birth was associated with an elevated risk of breast cancer. Among postmenopausal black women, obesity [as measured by body mass index (BMI)] was associated with an increased risk; among premenopausal women, there was no association of breast cancer with BMI. Women whose menopause occurred at or after age 50 were at increased risk relative to those whose menopause occurred earlier. There was no association between number of years of education and breast cancer in black women. History of benign breast disease and history of breast cancer in mother or sisters both were risk factors. The risk factor profile for breast cancer in black women was similar to that observed in whites.

Adult↗

Hydralazine and breast cancer.

Hydralazine (CAS: 86-54-4; 1-hydrazinonaphthalazine) is a well-established antihypertensive agent. There are no conclusive data on the drug as a human carcinogen, but one of its metabolites, hydrazine (CAS: 302-01-2), has been shown to be carcinogenic in rats and mice. To assess the relationship of hydralazine to human breast cancer, 3,419 women with breast cancer and 3,219 hospital control subjects were studied. Data were obtained by interview in hospitals in the United States and Canada. A total of 1.4% of the cases and 1.2% of the controls had used hydralazine. Compared with never use, the relative risk (RR) estimate for hydralazine that was first used at least 18 months before admission was 0.9 [95% confidence interval (CI), 0.5-1.7] after risk factors for breast cancer and the use of other antihypertensive drugs and diuretics were taken into account by multivariate analysis. The RR estimate for hydralazine use lasting at least 1 year was 0.9 (95% CI, 0.5-1.7). RR estimates for longer durations of use (up to 5 or more yr), and for use within strata of risk factors for breast cancer, were close to 1.0. The results suggest that hydralazine does not increase the risk of breast cancer in humans in the short term. Whether the risk is increased after latent intervals of many years could not be evaluated.

Adult↗

Venous thromboembolism in relation to oral contraceptive use.

The relation of the risk of venous thromboembolism to the use of oral contraceptives was assessed in a hospital-based study of 61 women suffering from a first episode of idiopathic deep vein thrombosis or pulmonary embolism (cases) and 1278 women admitted for trauma or respiratory infections (controls). Twenty (33%) of the cases and 121 (9%) of the controls had used oral contraceptives within the previous month, yielding an age-adjusted relative risk estimate of 8.1 (95% confidence interval 3.7 to 18) for recent users relative to never-users. For women using oral contraceptives containing less than 50 micrograms estrogen, the relative risk estimate was 11 (3.7 to 22); for preparations with 50 micrograms estrogen, it was 5.5 (2.1 to 15); and for preparations with more than 50 micrograms estrogen, it was 11 (3.9 to 30). Past use of oral contraceptives was not associated with an increased risk. The data suggest that the risk of venous thromboembolism is increased for recent oral contraceptive users relative to nonusers, even if women use oral contraceptives containing low doses of estrogen. Confidence intervals were wide, however, so that a reduction in the risk for users of lower dose formulations relative to users of higher dose formulations cannot be ruled out. Selection bias, if present, would have resulted in overestimation of the relative risk, but should not have distorted the comparisons according to dosage.

Adolescent↗

The risk of myocardial infarction 10 or more years after vasectomy in men under 55 years of age.

To evaluate whether vasectomy is associated with a subsequent increase in the incidence of myocardial infarction 10 or more years after surgery and whether an effect is more pronounced in those already predisposed to a myocardial infarction, a hospital-based case-control study was carried out in men aged less than 55 years. The men were interviewed during 1980-1983 in 78 hospitals in Massachusetts, Rhode Island, Connecticut, and New York. Among 2,238 men with first episodes of myocardial infarction, 332 (15%) had undergone vasectomy, compared with 572 (16%) of 3,361 controls. Vasectomy greater than or equal to 10 years earlier was reported by 150 cases and 180 controls, to yield a multivariate relative risk estimate of 1.0 after allowance for potential confounding factors (95% confidence interval (Cl) = 0.8-1.3); for vasectomy greater than or equal to 15 years before, based on 34 cases and 33 controls, the estimate was 1.1 (95% Cl = 0.7-2.0). In men predisposed to myocardial infarction because of more advanced age, cigarette smoking, elevated cholesterol level, hypertension, angina pectoris, or other risk factors, vasectomy did not appear to increase the risk further, even after intervals of greater than or equal to 10 years. The results provide evidence against an increased risk of myocardial infarction greater than or equal to 10 years after vasectomy overall and in those known to be predisposed because of other risk factors.

Adult↗

Does gallbladder removal protect against subsequent myocardial infarction?

It has been suggested that gallbladder removal may protect against subsequent development of myocardial infarction because of increased gastrointestinal cholesterol excretion resulting from increased enterohepatic cycling. To test this hypothesis, the authors used data from two large case-control studies of myocardial infarction--one conducted in 1976-1979 in 155 US hospitals and one conducted in 1980-1983 in 78 US hospitals. First, 550 female myocardial infarction cases were compared to 1,658 controls. Simultaneously adjusting for possible confounding variables using logistic regression, the odds ratio for development of a myocardial infarction subsequent to cholecystectomy was 0.8 (95% confidence interval, 0.5-1.1). Second, 1,511 male myocardial infarction cases were compared to 3,837 controls. With similar adjustments, the odds ratio was 0.8 (95% confidence interval, 0.5-1.2). The risk did not decline as the interval following cholecystectomy increased. The present data are compatible with a protective effect of cholecystectomy on the risk of subsequent myocardial infarction, but they are not conclusive.

Adult↗

Breast cancer risk in relation to early oral contraceptive use.

It has been suggested that the risk of breast cancer is increased by oral contraceptive use before the first birth, or by use before age 25, particularly if certain formulations are used. These hypotheses were evaluated in a hospital-based case-control study. A total of 521 patients under age 45 with breast cancer were compared with 521 controls matched for age, time of interview, and geographic area. Oral contraceptive use before the first birth was reported by 155 patients and 137 controls. With allowance for confounding by multivariate analysis, the estimated relative risk was 1.0 (95% confidence interval, 0.6-1.5). The estimate was 1.0 (0.2-3.9) for any use among nulliparous women and 0.6 (0.3-1.3) for use before the first birth among parous women. Use before age 25 was reported by 145 patients and 141 controls, and the multivariate relative risk estimate was 1.0 (0.7-1.6); the results were similar when use of specific formulations was examined. For oral contraceptive use before either the first birth or age 25, the relative risk estimates were compatible with 1.0 for use of five or more years' duration or an interval since first use of at least 15 years. There was also no evidence of an increased risk in any subgroup including those at increased underlying risk because of factors such as a family history of breast cancer or a history of cystic breast disease. The findings suggest that, up to age 45, the risk of breast cancer is not influenced by the use of oral contraceptives before the first birth or before age 25 even if the use lasted for five or more years.

Adult↗

The risk of myocardial infarction after quitting smoking in men under 55 years of age.

We assessed the effect of quitting cigarette smoking on the incidence of nonfatal myocardial infarction in men under the age of 55 in a case-control study of 1873 men with first episodes of myocardial infarction and 2775 controls. For "current" smokers (men who had smoked in the previous year) as compared with those who had never smoked, the estimated relative risk of myocardial infarction, adjusted for age, was 2.9 (95 per cent confidence interval, 2.4 to 3.4). Among exsmokers (those who had last smoked at least one year previously), the relative-risk estimate declined to a value close to unity for those who had abstained for at least two years; the estimate was 2.0 (1.1 to 3.8) for men who had abstained for 12 to 23 months, and the estimates were about 1.0 for men who had abstained for longer intervals. The results were unchanged by allowance for multiple potential confounding factors. A similar pattern was apparent among exsmokers who had smoked heavily for many years; among those predisposed to a myocardial infarction because of family history, hypertension, or other risk factors; and among those with no apparent predisposition. The results suggest that the risk of myocardial infarction in cigarette smokers decreases within a few years of quitting to a level similar to that in men who have never smoked.

Adult↗