Breast cancer and heredity: results of a population case-control study in Girona

BACKGROUND: To characterise the relationship between breast cancer and different aspects of the reproductive life, use of drugs and alcohol by family history of breast cancer. PATIENTS AND METHODS: From the cancer registry of Girona, Spain, 330 women were identified with histologically confirmed breast cancer during 1986-1989. For each case, a control woman was selected from a random sample of the population living in the matched area to the case by age (+/- 5 yr.). The information was collected by a personal interview and included: family history of breast cancer, reproductive history, presence of acne during the teenage years, use of oral contraceptives and drugs for sleep and anxiety disorders, and alcohol consumption. RESULTS: 18.5% of breast cancer cases and 8.9% of all controls had a family history of breast cancer. Family history on a first degree relative (mother or sister) was present in 10.6% of the cases and 2.8% of controls, which represented an odds ratio for breast cancer of 3.7 (95% CI, 1.8-7.8) higher than the general population. Women with a first degree family history of breast cancer were at higher risk for breast cancer if they had a history of acne during the teenage period (OR = 2.4; 95% CI, 1.1-5.2) and if they referred long menstrual periods in the early years of menarche (OR = 3.1; 95% CI, 1.3-7.0). Women with no family history had a higher breast cancer risk if they had a late menarche, long menstrual periods, late first full term pregnancy, and history of acne during puberty. Alcohol consumption and use of drugs for anxiety and sleep disorders were associated with a decreased risk of breast cancer. CONCLUSIONS: First degree family history of breast cancer seems to be the best risk indicator for developing breast cancer. Long menstrual periods and presence of acne during puberty may indicate hormonal imbalance that act independently of the family history in breast cancer development.     

A case-control study of dietary intake and other lifestyle risk factors for hyperplastic polyps

BACKGROUND & AIMS: Despite the high prevalence of the hyperplastic polyp, little is known about its etiology. The aim of this study was to assess the relationship between diet and other lifestyle factors and the presence of colorectal hyperplastic polyps. METHODS: Information on diet and other known or suspected risk factors for colorectal cancer or adenoma was collected among 81 subjects with hyperplastic polyps and 480 controls. RESULTS: The multivariate-adjusted odds ratio (OR) for hyperplastic polyps for individuals in the upper vs. the lower quartile was 0.30 (95% confidence interval [CI], 0.10-0.88) for dietary fiber, 0.32 (95% CI, 0.11-0.96) for dietary calcium, 0.90 (95% CI, 0.27-2.95) for total fat, and 2.02 (95% CI, 1.05-3.91) for alcohol consumption. Compared with individuals in the lower category, those in the upper category of body mass index had a higher risk for hyperplastic polyps (OR, 4.50; 95% CI, 1.84-10.97). Cigarette smoking was associated with a higher risk (OR, 1.97; 95% CI, 1.02-3.81 for > 20 pack-years vs. never), whereas an inverse association was seen for use of aspirin and other nonsteroidal anti-inflammatory drugs (OR, 0.29; 95% CI, 0.12-0.67 for once per day or more vs. never). CONCLUSIONS: Hyperplastic polyps share common lifestyle risk factors with colorectal adenomas and carcinomas.     

A case-control study of menopausal estrogen therapy and breast cancer

The association between estrogen replacement therapy and female breast cancer was studied in two Los Angeles area retirement communities. The 138 study cases of breast cancer occurring in residents younger than 75 years were compared with age- and race-matched community control subjects. The risk ratio for a total cumulative dose in excess of 1,500 mg was estimated to be 2.5 in women with intact ovaries. This increase was present using various independent sources of drug usage information but was inconsistent at low dose and undetectable in oophorectomized women. No important sources of confounding could be identified, and no risk modifiers could be identified except for a history of surgically confirmed benign breast disease. In such women with intact ovaries, the risk ratio for a high cumulative dose rose to 5.7 relative to nonusers with normal breasts.     

Risk factors for familial and sporadic ovarian cancer among French Canadians: a case-control study

OBJECTIVE: The objective was to compare risk factors between familial and sporadic ovarian cancer by means of a case-control approach. STUDY DESIGN: We conducted a case-control study among French Canadian women in Montreal during 1995-1996. One hundred seventy women 20 to 84 years old with histologically confirmed diagnoses of primary ovarian carcinomas or borderline tumors were interviewed concerning their reproductive, family, and medical histories. During the same period 170 randomly selected population control subjects, frequency-matched to the case patients according to age and ethnic group, were also interviewed. Unconditional logistic regression methods were used for data analysis. RESULTS: The major factors influencing the risk of development of ovarian cancer were as follows: (1) family history of breast or ovarian cancer, (2) a late age at use of oral contraceptives (a protective effect), and (3) a late age at last childbirth (a protective effect for familial case patients only). CONCLUSION: These factors had equally great impacts in familial and sporadic cases, implying that the underlying mechanisms of carcinogenesis in sporadic and familial ovarian cancer may be similar and that hereditary ovarian cancer may be preventable.     

Garlic, onion and cereal fibre as protective factors for breast cancer: a French case-control study

The role of diet on breast cancer risk was investigated in a case-control study of 345 patients diagnosed with primary breast carcinoma between 1986 and 1989 in the north-east of France (Lorraine). For each case, one control was matched for age (+/-3 years) and socio-economic status. The dietary history questionnaire consisted of a self-administered food frequency questionnaire, a 6-day food diary and an energy expenditure record. It also elicited personal characteristics and medical history. While taking into account total caloric intake and established risk factors, breast cancer risk was shown to decrease as consumption of fibre (p value for trend = 0.03), and garlic and onions (p value for trend <10(-6)) increased. This study also supports the epidemiologic evidence that saturated fat intake and breast cancer risk are associated in post-menopausal women (p value for trend = 0.03). Conversely, it suggests that unsaturated fat intake could lower the risk in the same subgroup (p value for trend = 0.03). Our findings on protective factors of breast cancer could induce effective preventive measures and warrant further experimental investigations to isolate specific subfractions.     

Urinary estrogen metabolites and breast cancer: a case-control study

Preliminary studies suggest that the estrogen metabolite 16 alpha-hydroxyestrone is associated with breast cancer, whereas 2-hydroxyestrone is not. However, epidemiological studies evaluating this relationship and taking established risk factors for breast cancer into account are lacking. The purpose of this study was to examine the association of the ratio of the urinary estrogen metabolites (2-hydroxyestrone and 16 alpha-hydroxyestrone) and of the individual metabolites with breast cancer. A spot urine sample, a brief history, and clinical data were collected from breast cancer cases (n = 42) and from women coming to the hospital for a routine mammogram or attending a free breast cancer screening (n = 64). 2-Hydroxyestrone and 16 alpha-hydroxyestrone were measured by enzyme immunoassay, and the estrogen metabolite ratio (EMR; 2-hydroxyestrone:16 alpha-hydroxyestrone) was computed. Cases and controls were similar in terms of age (mean age of cases, 53.8 +/- 15.1 years, versus 54.2 +/- 10.4 years for controls; P = 0.9) and demographics. Mean EMR was not associated with breast cancer overall (1.67 +/- 0.80 versus 1.72 +/- 0.66; P = 0.7). However, in postmenopausal women, the mean EMR was significantly lower in cases compared to controls (1.41 +/- 0.73 versus 1.81 +/- 0.71; P = 0.05). The multivariate adjusted odds ratios for the intermediate and lowest tertiles of the EMR relative to the highest among postmenopausal women were 9.73 (95% confidence interval, 1.27-74.84) and 32.74 (95% confidence interval, 3.36-319.09), respectively. The test for trend was highly significant (P = 0.003). Analyses of the individual metabolites indicated that 16 alpha-hydroxyestrone was a strong risk factor. The EMR did not show any consistent associations with age, race/ethnicity, age at first birth, parity, body mass index, family history of breast cancer, smoking, or alcohol intake. These data suggest a strong, inverse association of the EMR and a strong positive association of 16 alpha-hydroxyestrone with breast cancer in postmenopausal women. Larger studies are needed to confirm these results and to assess the relationship of the EMR and of the individual metabolites with breast cancer, with attention to menopausal status and clinical factors and with adjustment for known breast cancer risk factors.     

Dental and cardiac risk factors for infective endocarditis. A population-based, case-control study

BACKGROUND: Although antibiotic prophylaxis against infective endocarditis is recommended, the true risk factors for infective endocarditis are unclear. OBJECTIVE: To quantitate the risk for endocarditis from dental treatment and cardiac abnormalities. DESIGN: Population-based, case-control study. SETTING: 54 hospitals in the Philadelphia area. PATIENTS: Persons with community-acquired infective endocarditis not associated with intravenous drug use were compared with community residents, matched by age, sex, and neighborhood of residence. MEASUREMENTS: Information on demographic characteristics, host risk factors, and dental treatment was obtained from structured telephone interviews, dental records, and medical records. RESULTS: During the preceding 3 months, dental treatment was no more frequent among case-patients than controls (adjusted odds ratio, 0.8 [95% CI, 0.4 to 1.5]). Of 273 case-patients, 104 (38%) knew of previous cardiac lesions compared with 17 controls (6%) (adjusted odds ratio, 16.7 [CI, 7.4 to 37.4]). Case-patients more often had a history of mitral valve prolapse (adjusted odds ratio, 19.4 [CI, 6.4 to 58.4]), congenital heart disease (adjusted odds ratio, 6.7 [CI, 2.3 to 19.4]), cardiac valvular surgery (adjusted odds ratio, 74.6 [CI, 12.5 to 447]), rheumatic fever (adjusted odds ratio, 13.4 [CI, 4.5 to 39.5]), and heart murmur without other known cardiac abnormalities (adjusted odds ratio, 4.2 [CI, 2.0 to 8.9]). Among case-patients with known cardiac lesions--the target of prophylaxis--dental therapy was significantly (P = 0.03) less common than among controls (adjusted odds ratio, 0.2 [CI, 0.04 to 0.7] over 3 months). Few participants received prophylactic antibiotics. CONCLUSIONS: Dental treatment does not seem to be a risk factor for infective endocarditis, even in patients with valvular abnormalities, but cardiac valvular abnormalities are strong risk factors. Few cases of infective endocarditis would be preventable with antibiotic prophylaxis, even with 100% effectiveness assumed. Current policies for prophylaxis should be reconsidered.     

Meat, fat and risk of breast cancer: a case-control study from Uruguay

To examine whether meat intake modifies breast-cancer risk, a case-control study was conducted in Uruguay. Dietary patterns were assessed in detail (for cases, before diagnosis or symptoms occurred) using a food frequency questionnaire involving 64 food items, which allowed total energy intake to be calculated. Nutrient residuals were calculated through regression analysis. After adjustment for potential confounders (which included family history of breast cancer, menopausal status, body-mass index, total energy and total alcohol intake), an increased risk associated with consumption of total meat intake, red meat intake, total fat and saturated fat intake was observed. The strongest effect was observed for red meat intake (OR 4.2, 95% CL 2.3-7.7) for consumption in the upper quartile, after controlling for protein and fat intake. This suggests an independent effect for meat. Since experimental studies have shown a strong effect of heterocyclic amines in rat mammary carcinogenesis, further studies should be performed in human epidemiology, perhaps using biomarkers of heterocyclic amine exposure.     

A case-control study of prostate cancer

We present tyndallometry as a method for investigation of subclinical changes in anterior-chamber flare in patients with risk factors regarding anterior-segment ischemia after squint surgery. The cases of six adult patients who underwent surgery on the vertical recti and who had additional risk either because of dysthyroid orbitopathy or because of transpositions carried out on the recti are presented. In one case a transient subclinical increase in the flare value was observed. This noninvasive method seems suitable for the provision of further information on the pathophysiology of anterior-segment ischemia and for monitoring of patients at special risk postoperatively such that early treatment can be started if necessary. Additionally, early detection of nonischemic intraocular inflammation in the postoperative course is rendered possible by this examination.     

Lifestyle factors and prostate cancer risk: a case-control study in Sweden

We examined associations between lifestyle factors and subsequent risk of prostate cancer in a population-based case-control study. Information on smoking and alcohol habits, socioeconomic factors, marital status, family history, and sexual habits were obtained from a questionnaire and a face-to-face interview with 256 (74.6%) eligible patients and 252 (76.6%) selected controls, frequency matched by age and screened for prostate cancer with negative findings. Unconditional logistic regression was used to estimate the odds ratios (ORs). Risk was elevated among current smokers of cigarettes (OR, 1.8) and current users of hard liquor (OR, 1.4); however, the lack of dose-response trend for both of these exposures argues against a causal association. We found tentative evidence that early first intercourse, a larger number of sexual partners, and other indices of high sexual activity are associated with increased risk. Similarly, adult height, an indicator of nutrition during childhood and adolescence, was weakly positively associated with risk, although larger studies are needed to establish this link. Unmarried men had a lower risk than married men (OR, 0.3), and socioeconomic status did not appear to be strongly associated with prostate cancer. Men with a father who had prostate cancer had a more than 2-fold increased risk of prostate cancer, whereas those with a brother affected had about a 5-folk risk.     

Anthropometric and other risk factors for ovarian cancer in a case-control study

Because it has been suggested that an environmental factor may play a role in the etiology of ovarian cancer, a case-control study was conducted to assess some environmental and other risk factors for ovarian cancer from 1994 to 1996 in northern Kyushu, Japan. We analyzed the data of 89 cases with epithelial ovarian cancer and 323 controls without any cancer or ovarian disorder. After controlling for the effect of potential confounders, the odds ratios of ovarian cancer across increasing quartiles of the heaviest body weight were 1.00, 1.15, 1.71, 2.29 (P = 0.008, test for trend). Significantly increased risks were noted for a history of diabetes mellitus (P < 0.05), and for a family history of ovarian cancer (P < 0.05). Significantly decreased trends for risk were obtained for the number of pregnancies (P < 0.01) and the number of live births (P < 0.001). This study provides additional support for an association between obesity and the risk of ovarian cancer. This relationship may at least partly explain the recent increase in the incidence of ovarian cancer in Japan, although possible contributions of other factors can not be ruled out.     

Associations between congenital malformations and childhood cancer. A register-based case-control study

This report describes a population-based case-control study that aimed to assess and quantify the risk of children with congenital malformations developing cancer. Three sources of data were used: the Victorian Cancer Register, the Victorian Perinatal Data Register (VPDR) and the Victorian Congenital Malformations/Birth Defects Register. Cases included all Victorian children born between 1984 and 1993 who developed cancer. Four controls per case, matched on birth date, were randomly selected from the VPDR. Record linkage between registers provided malformation data. A matched case-control analysis was undertaken. Of the 632 cancer cases, 570 (90.2%) were linked to the VPDR. The congenital malformation prevalence in children with cancer was 9.6% compared with 2.5% in the controls [odds ratio (OR) 4.5, 95% CI 3.1-6.7]. A strong association was found with chromosomal defects (OR=16.7, 95% CI 6.1-45.3), in particular Down's syndrome (OR=27.1, 95% CI 6.0-122). Most other birth defect groups were also associated with increased cancer risk. The increased risk of leukaemia in children with Down's syndrome was confirmed, and children with central nervous system (CNS) defects were found to be at increased risk of CNS tumours. The report confirms that children with congenital malformations have increased risks of various malignancies. These findings may provide clues to the underlying aetiology of childhood cancer, as congenital malformations are felt to be a marker of exposures or processes which may increase cancer risk. The usefulness of record linkage between accurate population-based registers in the epidemiological study of disease has also been reinforced.     

A case-control study of the relationship between dietary factors and risk of lung cancer in women of Shenyang, China

A 1:1 case-control study of lung cancer incidence among women in Shenyang was conducted to explore the relationship between diet and the risk of lung cancer, with emphasis on the potential effects of a list of specific dietary constituents on modifying lung cancer risks. Dietary information on 290 cases and population-matched controls was obtained by personal interviews. Multiple logistic regression models were used for the statistical analysis and summarization of the data. A significant difference was found between cases and controls with respect to intake of beta-carotene, vitamin C and fibers, all of which reduced the risk for lung cancer in a dose-dependent manner; yielding calculated odds ratio (OR) of 0.84, 0.75, and 0.46, respectively. The apparent effects of these nutrients persisted after adjusting for cigarette smoking;suggesting that they may function as protective factors to reduce the risk for lung cancer in Chinese women.     

Adult height and risk of breast cancer among white women in a case-control study

Data from a hospital-based case-control study were analyzed to evaluate the relation of adult height to the risk of breast cancer among white women. The authors compared 5,358 newly diagnosed breast cancer cases and 4,555 controls interviewed from 1976 to 1992 in hospitals located mainly in the United States. Overall, there was no association between stature and risk of breast cancer. In comparison with women whose heights were less than 62 inches (< 158 cm), the adjusted odds ratios were 1.1 (95% confidence interval (Cl) 0.9-1.2), 1.0 (95% Cl 0.9-1.2), 1.0 (95% Cl 0.9-1.1), and 1.0 (95% Cl 0.8-1.2) for women with heights of 62-63, 64-65, 66-67, and > or = 68 inches (equivalent to 158-160, 163-165, 168-170, and > or =173 cm), respectively. There was no consistent evidence of modification of the effect of height by other risk factors. The results suggest that adult stature in white women is not related to the risk of breast cancer.     

Dichlorodiphenyltrichloroethane serum levels and breast cancer risk: a case-control study from Mexico

Some, but not all, epidemiological studies have suggested that dichlorodiphenyltrichloroethane (DDT) may play a role in the development of breast cancer. These investigations have been conducted in countries where this substance has been banned for at least 20 years. We conducted a study in Mexico, a country in which DDT is still being used to control malaria. In a hospital-based case-control study, we compared 141 histologically confirmed cases of breast cancer with 141 age-matched controls (+/-3 years). All subjects were identified at three referral hospitals of Mexico City between March 1994 and April 1996. Reproductive histories and other variables were obtained by structured interviews, DDT/DDE levels were determined in serum by gas-liquid chromatography. The arithmetic mean of serum DDE in lipid basis was 562.48 +/- 676.18 ppb (range, 10.24-4661.44) for the cases and 505.46 +/- 567.22 ppb (range, 0.004 to 4361.75) for the controls, but this difference was not statistically significant. The age-adjusted odds ratios for breast cancer regarding the serum level of DDE were 0.69 (95% confidence interval, 0.38-1.24) and 0.97 (confidence interval, 0.55-1.70) for the contrasts between tertile 1 (lowest level) and tertiles 2 and 3, respectively. These estimates were unaffected by adjustment for body mass, accumulated time of breast-feeding and menopause, and other breast cancer risk factors. These results do not lend support to the hypothesis that DDT is causally related to breast cancer at the body-burden levels found in our study population but do not exclude the possibility that higher levels of exposure could still play a role in the etiology of this tumor.     

Alcohol consumption and risk of breast cancer: a multicentre Italian case-control study

The relationship between alcohol consumption and breast cancer risk was investigated using data from a co-operative case-control study conducted in Italy between 1991 and 1994 on 2569 incident, histologically confirmed breast cancer cases and 2588 controls in hospital for acute, non-neoplastic, non-hormone related conditions. Overall, 915 (38%) cases and 1048 (43%) controls were abstainers. Compared with them, the odds ratio (OR), adjusted only for age, was 1.31 (95% confidence interval (CI) 1.13-1.53) for drinkers and became 1.39 (95% CI 1.(1)21-1.60) after correction for measurement error. The multivariate OR was 1.21 for drinkers of < or = 5.87 g/day and 1.23, 1.19, 1.21, 1.41 for drinkers of 5.88-13.40, 13.41-24.55, 24.56-27.60, > 27.60 g/day, respectively. The trend in risk was significant (chi 2 = 12.28, P < 0.0005). The association was apparently stronger in premenopausal women (OR = 1.80 for > 27.60 g/day). Considering the different types of alcoholic beverages (wine, beer, digestives, grappa and other spirits), a significant direct trend in breast cancer risk was seen for wine with an OR of 1.27 (95% CI 1.06-1.53) for the category > 26.34 g/day. The ORs were also above unity for beer, grappa, digestives and spirits drinkers. No appreciable interaction was observed between alcohol drinking and body mass index, smoking, or any other covariate considered. Thus, the present data, based on a validated alcohol consumption questionnaire and on a population characterised by a relatively high alcohol consumption in women, confirmed that alcohol drinking is moderately related to breast cancer risk. If causal, this association could explain 12% (95% CI, 5-19%) of breast cancers in Italy, thus representing one of the major avoidable risk factor for breast cancer.     

Myocardial infarction in Girona, Spain: attack rate, mortality rate and 28-day case fatality in 1988. Regicor Study Group

This study was conducted to establish the attack rate, mortality rate and 28-day case-fatality rates of acute myocardial infarction (AMI) occurring in Girona, Spain, between October 1987 and September 1988. The study was carried out using a population register of AMI, and took place in one central hospital, and eight county hospitals in Girona (in the autonomous community of Catalonia, northeast Spain). Subjects comprised 222 fatal cases selected from 4069 death certificates, and 210 non-fatal cases from hospital records, among subjects aged between 25 and 74 years (reference population 263,778). The age standardized attack rate was 105.6 per 100,000 inhabitants in the age group 35-64 (193.6 in men and 17.6 in women). The age standardized mortality rate was 36.3 per 100,000 inhabitants in the age group 35-64 (63.1 among men and 9.9 among women). The age standardized 28-day case-fatality was 34.6% in men and 50.1% in women in this same age group. Attack and mortality rates of AMI in a region of Spain are presented for the first time. These rates are lower than in other developed countries, nevertheless the 28-day case-fatality is similar to that of these countries.     

Risk factors for rifampin-monoresistant tuberculosis: A case-control study

Rifampin is the cornerstone of short-course chemotherapy for the treatment of tuberculosis (TB). Rifampin monoresistance (RMR) is less common than resistance to isoniazid alone or in combination with other antituberculous medications. We conducted a retrospective case-control study to identify risk factors for RMR-TB. Complete records for 21 of a total of 26 RMR patients from 1990 to 1997 were available for review, and were compared with those of 48 patients with drug-susceptible TB, controlling for year of diagnosis. Cases more frequently had a history of TB than did controls (61% versus 22%, p < 0.01), and were more often human immunodeficiency virus (HIV) positive (81% versus 46%, p = 0.02). With control for HIV status, cases were more likely to have extrapulmonary involvement (47.6% versus 11.6%, p = 0.05). Four cases (19%) and one control (2. 1%) died (p = 0.02) during hospitalization. Cases more often had a history of incarceration (71.4% versus 37.5%, p = 0.09). Among the 13 cases with a history of TB, five had evidence of malabsorption (vomiting and/or diarrhea), versus none of the 11 controls with prior TB. These data support the hypothesis that RMR is seen primarily in individuals with a history of TB and who are HIV positive. Cases were frequently noncompliant with previous treatment for TB, had a history of incarceration, and had poor outcomes.