Increased risk of breast cancer with alcohol consumption in postmenopausal women.

The association between breast cancer incidence and alcohol consumption among postmenopausal women was examined in the Iowa Women's Health Study. In January 1986, a cohort of 41,837 postmenopausal women, aged 55-69 years, completed a questionnaire that included alcohol intake and other information. Through December 1989, 493 incident breast cancer cases were identified. Age-adjusted relative risks of consumption of less than 1.5, 1.5-4.9, 5.0-14.9, and 15.0 g or more of alcohol per day compared with abstention were 1.08, 1.10, 1.08, and 1.28, respectively (p for trend = 0.11). After controlling for age, body mass index, age at first livebirth, age at menarche, and family history of breast cancer, the relative risks were 1.18, 1.20, 1.25, and 1.46 (p for trend = 0.04). Multivariate modeling, using Cox proportional hazards regression, revealed a significant multiplicative interaction between alcohol intake and noncontraceptive estrogen use. The relative risks of breast cancer associated with average daily alcohol consumption of 5.0-14.9 and 15.0 g or more were 1.88 (95% confidence interval 1.30-2.72) and 1.83 (95% confidence interval 1.18-2.85), respectively, among ever-users of estrogen; no association between alcohol and breast cancer was observed among never-users of estrogen.     

Studies of breast cancer and alcohol consumption

Alcohol consumption as a potential risk factor for breast cancer was examined in a case-control study of 1,467 female breast cancer patients and 10,178 hospital controls. Lean females (Quetelet index less than 22) had elevated unadjusted odds ratios for breast cancer of 2.1, 1.7, and 1.4, associated with consuming less than 5, 5-15, and greater than 15 g of alcohol per day, respectively. However, this pattern is not consistent with a dose-response, and adjustment for a risk profile of confounding factors, including education and occupation (which are strong correlates of age at first pregnancy and parity), reduced these estimates to 1.4, 1.2, and 0.9; none of which differs significantly from 1.0. Among all subgroups, the odds ratios adjusted for pertinent confounders and interactions fluctuated randomly by about 0.9 and showed no consistent trend with increased alcohol consumption. In a second investigation, proportional breast cancer rates were estimated for female veterans diagnosed in Veterans Administration Hospitals during 1970-1982 using 1973-1977 rates for the general population as the standard of comparison. In the VA cohort of females, which had an approximate twofold higher prevalence of alcohol abuse and chronic cigarette smoking, the proportional rates of known alcohol and tobacco-related malignancies were significantly elevated but the rates of breast cancer were not. The standardized proportional morbidity rates of breast cancer for white, black, and all VA females were 0.92, 0.85, and 0.91, respectively. Although these results do not rule out weak associations between breast cancer and alcohol in certain subgroups, neither do they provide any compelling evidence that alcohol has a role in the genesis of this malignancy.     

Dose-specific meta-analysis and sensitivity analysis of the relation between alcohol consumption and lung cancer risk

Alcohol drinking increases the risk of several types of cancer, but studies of the relation between alcohol and lung cancer risk are complicated by smoking. The authors carried out meta-analyses for four study designs and conducted sensitivity analyses to assess the results. Pooled smoking-unadjusted relative risks (RRs) for brewery workers and alcoholics were 1.17 (95% confidence interval (CI): 0.99, 1.39) and 1.99 (95% CI: 1.66, 2.39), respectively, relative to population rates. For cohort and case-control studies, the authors conducted dose-specific meta-analyses for ethanol consumption of 1-499, 500-999, 1,000-1,999, and > or = 2,000 g/month, relative to nondrinking. Smoking-adjusted RRs for ascending dose groups in cohort studies were 0.98 (95% CI: 0.79, 1.21), 0.92 (95% CI: 0.81, 1.04), 1.04 (95% CI: 0.88, 1.22), and 1.53 (95% CI: 1.04, 2.25), respectively. Smoking-adjusted odds ratios for ascending groups in case-control studies were 0.63 (95% CI: 0.51, 0.78), 1.30 (95% CI: 0.98, 1.70), 1.13 (95% CI: 0.46, 2.75), and 1.86 (95% CI: 1.39, 2.49), respectively. Elevated odds ratios were seen for hospital-based case-control studies but not for population-based case-control studies. Sensitivity analyses indicated that smoking explained the elevated RRs in studies of alcoholics and that strong misclassification of smoking status could produce an elevated smoking-adjusted RR in cohort and case-control studies. Overall, evidence for a smoking-adjusted association between alcohol and lung cancer risk is limited to very high consumption groups in cohort and hospital-based case-control studies. At lower levels, any associations observed appear to be explained by confounding.     

Fish consumption and breast cancer risk

The omega-3 fatty acids, especially long-chain eicosapentaenoic acid (20:5n-3) and docosahexaenoic (22:6n-3) contained in "fatty" fish, have consistently been shown to retard the growth of breast cancer in vitro and in animal experiments. In contrast, studies of the association between fish consumption and breast cancer risk in human populations have not consistently shown inverse associations. However, previous studies have not considered the specific types of fish consumed. Using data from a large, nationwide case-control study conducted in Sweden, we examined the association between consumption of fatty and lean fish and breast cancer risk. Odds ratios (OR) and 95% confidence intervals were computed from unconditional logistic regression models. High consumption of fish was weakly associated with reduced breast cancer risk, and the association was not statistically significant. With multivariate adjustment, the OR for women with the highest consumption (> or =3.5 servings/wk) compared with women with the lowest (virtually none) was 0.88 (95% confidence interval = 0.60-1.29, P for trend = 0.15). When type of fish was examined separately, the association was similar for fatty and lean fish.     

Alcohol consumption and the risk of breast cancer

To examine the relation between alcohol consumption and breast cancer, the authors used data from the Centers for Disease Control's Cancer and Steroid Hormone Study, a multicenter population-based case-control study. Between August 1981 and December 1982, 3,498 US women aged 20-54 years with newly diagnosed breast cancer and 3,157 women aged 20-54 years selected at random from the same geographic areas were asked about their consumption of alcoholic beverages during the previous five years. Women who drank any alcohol had a risk of breast cancer of 1.0 (95% confidence interval 0.9-1.2) compared with nondrinkers. The risk of breast cancer did not increase appreciably with increasing alcohol consumption: Risk estimates for women consuming 8-14, 15-21, and 22 or more drinks per week were 1.1, 1.0, and 1.2, respectively. The authors also found no notable differences by type of beverage or within specific risk factor subgroups. These findings do not support the hypothesis that alcohol consumption increases the risk of breast cancer.     

Lifetime alcohol intake and breast cancer risk

PURPOSE: Moderate alcohol intake of one to two drinks per day has been consistently associated with a 30-50% increase in breast cancer. Despite the consistency in the overall association, several important questions remain, including whether the association between alcohol intake and breast cancer risk is affected by the timing of alcohol exposure, modified by other risk factors such as body mass index (BMI), menopausal status, and hormone replacement therapy (HRT), or more pronounced among hormone receptor positive tumors or invasive rather than in situ disease. METHODS: To address these questions, we conducted a large population-based study (1508 cases and 1556 controls) that collected detailed information on alcohol and other exposures throughout the lifecourse. RESULTS: Consumption of 15-30 grams/day (approximately one to two drinks) throughout life was associated with a modest 33% increase in risk (odds ratio [OR] = 1.33, 95% confidence interval (CI) = 1.01-1.74), but heavier consumption (> or = 30 grams per day) was not. Risk did not vary with alcohol type (beer, wine, or hard liquor) or by patterns of use, such as recent use, intake prior to age 20 years, or whether use began at an early age. The association with lifetime intake was limited to women with a BMI < 25 (OR = 2.13, 95% CI = 1.29-3.54). Alcohol consumption of approximately one drink per day was associated with estrogen receptor positive tumors among women with a BMI < 25, but not among women BMI > or = 25. Also, the elevated OR was observed only among women diagnosed with invasive (OR = 1.56, 95% CI = 1.11-2.18), but not in situ breast tumors. CONCLUSIONS: These data give added support that moderate alcohol consumption over the life course increases breast cancer risk, particularly among women with low BMI and those diagnosed with estrogen receptor positive tumors or with invasive rather than in situ disease. Risk is confined to moderate intake and does not vary with the timing of use, with heavier doses, or with the type of alcohol consumed.     

Low-to-moderate alcohol consumption and breast cancer risk by age 50 years among women in Germany

Studies of the association between alcohol drinking and breast cancer show a tendency towards an increase in risk for high consumption levels but yield less consistent results for low-to-moderate levels, particularly among premenopausal women. In a population-based case-control study in Germany, the authors determined the effect of alcohol consumption at low-to-moderate levels on breast cancer risk among women up to age 50 years. The study included 706 case women whose breast cancer had been newly diagnosed in 1992-1995 and 1,381 residence- and age-matched controls. In multivariate conditional logistic regression analysis, the adjusted odds ratios for breast cancer were 0.71 (95% confidence interval (CI): 0.54, 0.91) for average ethanol intake of 1-5 g/day, 0.67 (95% CI: 0.50, 0.91) for intake of 6-11 g/day, 0.73 (95% CI: 0.51, 1.05) for 12-18 g/day, 1.10 (95% CI: 0.73, 1.65) for 19-30 g/day, and 1.94 (95% CI: 1.18, 3.20) for > or = 31 g/day. The association with high daily ethanol intake of > or = 19 g was modified by educational level, such that odds ratios were 3.7, 1.6, and 0.7 for women with low, moderate, and high levels of education, respectively. These data suggest that low-level consumption of alcohol does not increase breast cancer risk in premenopausal women.     

Dietary supplements of dehydroepiandrosterone in relation to breast cancer risk

OBJECTIVE: Dietary supplements of the adrernocertical hormone dehydroepiandrosterone (DHEA) are widely taken in the hope of staving off the aging process. Potential dangers have not been fully researched, particularly evidence of a correlation between increased serum concentrations of DHEA and higher breast cancer risk in postmenopausal women. DESIGN: The review examines reports of clinical, epidemiological experimental studies for evidence that DHEA may be a factor in promoting the growth of mammary cancer. Biological mechanisms which might be involved are identified. RESULTS: DHEA is reported to inhibit the growth of human mammary cancer cells in vitro and also the growth of chemically-induced mammary cancer in rats. However, growth inhibition occurs only in the presence of high oestrogen concentrations, and growth stimulation occurs in both models in the presence of a low-level oestrogen milieu. Epidemiological studies report a positive correlation between higher serum concentrations of DHEA and increased breast cancer risk in the case of postmenopausal but not premenopausal women. Postulated mechanisms include a direct effect on mammary cells by androgenic metabolites of DHEA or an indirect effect by an increase in bioavailable oestrogen levels. The increased serum concentration of free insulin-like growth factor 1 which follows prolonged DHEA intake may also have a role by stimulating oestrogen receptor activity in breast tissue. CONCLUSION: Late promotion of breast cancer in postmenopausal women may be stimulated by prolonged intake of DHEA, and the risk may be increased by the endocrine abnormality associated with pre-existing abdominal obesity. Caution is advised in the use of dietary supplements of DHEA particularly by obese postmenopausal women.     

An epidemiological case-control study of breast cancer and alcohol consumption

A case-control study of breast cancer and alcohol consumption was conducted with 1617 patients diagnosed with a primary cancer of the breast between 1982 and 1984 in 18 New York State counties. For each case, one control, matched for year of birth and county of residence, was selected from the driver's license files of the New York State Department of Motor Vehicles. Breast cancer risk was shown to increase as daily consumption of alcohol increased, with a risk of 1.37 (95% Cl = 1.07, 1.75) observed among women who consumed 15 or more grams of alcohol per day. Breast cancer risk did not appear to be related to the total number of years a woman drank or to be restricted to specific types of alcoholic beverages. The data suggest that this may be higher in women who began drinking at a later age. The increased risk associated with alcohol consumption, observed in the current study, persisted within strata of various breast cancer risk factors.     

Left-handedness in relation to breast cancer risk in postmenopausal women

Breast cancer risk may be influenced by intrauterine exposure to steroid hormones. We evaluated left-handedness, a marker of intrauterine hormone exposure, in relation to breast cancer risk in our population-based, case-control study. Case women 50-79 years of age with a first diagnosis of invasive breast cancer were ascertained through statewide cancer registries in Wisconsin, Massachusetts, and New Hampshire. Control women were identified in each state through lists of licensed drivers (for ages 50-64) and Medicare beneficiaries (for ages 65-79), and selected at random to correspond with the age distribution of case women. Exposure information, including handedness, was obtained through a telephone interview. Our results indicated a modest association between left-handedness and breast cancer risk (OR = 1.42; 95% CI = 1.10-1.83). The effect of left-handedness was modified by age; we observed the greatest risk ratio in the oldest age group. Left-handedness was not associated with breast tumor laterality. Our results are consistent with the hypothesis that intrauterine hormone exposures play a role in the development of breast cancer.     

Risk of papillary thyroid cancer in women in relation to smoking and alcohol consumption

Both smoking and alcohol consumption may influence thyroid function, although the nature of these relations is not well understood. We examined the influence of tobacco and alcohol use on risk of papillary thyroid cancer in a population-based case-control study. Of 558 women with thyroid cancer diagnosed during 1988-1994 identified as eligible, 468 (83.9%) were interviewed; this analysis was restricted to women with papillary histology (N = 410). Controls (N = 574) were identified by random digit dialing, with a response proportion of 73.6%. We used logistic regression to calculate odds ratios (OR) and associated confidence intervals (CI) estimating the relative risk of papillary thyroid cancer associated with cigarette smoking and alcohol consumption. A history of ever having smoked more than 100 cigarettes was associated with a reduced risk of disease (OR = 0.7, 95% CI = 0.5-0.9). This reduction in risk was most evident in current smokers (OR = 0.5, 95% CI = 0.4-0.7). Women who reported that they had ever consumed 12 or more alcohol-containing drinks within a year were also at reduced risk (OR 0.7, 95% CI = 0.5-1.0). Similar to the association noted with smoking, the reduction in risk was primarily present among current alcohol consumers. The associations we observed, if not due to chance, may be related to actions of cigarette smoking and alcohol consumption that reduce thyroid cell proliferation through effects on thyroid stimulating hormone, estrogen, or other mechanisms.     

饮酒与肺癌发病关联的Meta分析

目的探讨饮酒与肺癌的关系。方法全面检索相关文献,应用Meta分析方法对各研究进行数据合并与分析。结果纳入合并分析的文章共21篇,其中队列研究6篇,随访人数累计122288例,病例3053例;病例对照研究15篇,累计病例8838例,对照21591例。Meta分析饮酒与肺癌合并OR值为1.17(95%CI:0.96～1.42);男、女饮酒合并OR值分别为1.67(95%CI:0.61～4.59)和0.93(95%CI:0.51～1.68);男性饮啤酒合并OR值为1.46(95%CI:1.28～1.67);饮烈酒合并OR值为1.34(95%CI:1.02～1.74);饮酒≥7次/周与肺癌呈正相关(P<0.05)。结论饮用啤酒、烈酒和经常饮酒与肺癌有统计学关联。     

Potential exposure to PCBs, DDT, and PBDEs from sport-caught fish consumption in relation to breast cancer risk in Wisconsin

In Wisconsin, consumption of Great Lakes fish is an important source of exposure to polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), polybrominated diphenyl ethers (PBDEs), and other halogenated hydrocarbons, all of which may act as potential risk factors for breast cancer. We examined the association between sport-caught fish consumption and breast cancer incidence as part of an ongoing population-based case-control study. We identified breast cancer cases 20-69 years of age who were diagnosed in 1998-2000 (n = 1,481) from the Wisconsin Cancer Reporting System. Female controls of similar age were randomly selected from population lists (n = 1,301). Information about all sport-caught (Great Lakes and other lakes) fish consumption and breast cancer risk factors was obtained through telephone interviews. After adjustment for known and suspected risk factors, the relative risk of breast cancer for women who had recently consumed sport-caught fish was similar to women who had never eaten sport-caught fish [relative risk (RR) = 1.00; 95% confidence interval (CI), 0.86-1.17]. Frequency of consumption and location of sport-caught fish were not associated with an increased risk of breast cancer. Recent consumption of Great Lakes fish was not associated with postmenopausal breast cancer (RR = 0.78; 95% CI, 0.57-1.07), whereas risk associated with premenopausal breast cancer was elevated (RR = 1.70; 95% CI, 1.16-2.50). In this study we found no overall association between recent consumption of sport-caught fish and breast cancer, although there may be an increased breast cancer risk for subgroups of women who are young and/or premenopausal.     

Anthropometric variables in relation to risk of breast cancer in middle-aged women

BACKGROUND: Many epidemiological studies have assessed the relationships between anthropometric variables and breast cancer risk. However, methodological approaches for analysing these factors differ appreciably. Also, age when maximum height is achieved has been identified as a potential risk factor for breast cancer in premenopausal women, but this issue has not been studied in postmenopausal women. METHODS: The participants in this population-based case-control study were postmenopausal women 50-64 years of age from the general female population of western Washington State. It included 479 women with incident primary breast cancer and 435 controls. RESULTS: This study found that: (i) women who gained over 70 pounds since age 18 had an increased risk of breast cancer relative to those who stayed within 10 pounds of their weight at age 18 (odds ratio [OR] = 2.7; 95% CI: 1.5-4.9), (ii) women with body mass indices (BMI) below what is considered healthy had a decreased risk (OR = 0.4; 95% CI: 0.2-1.1) while women with a BMI in the obese range had an increased risk of breast cancer (OR = 1.4; 95% CI: 1.0-2.1), and (iii) women who reached their maximum height at or after the age of 18 had a decreased risk of breast cancer compared to women who reached their maximum height at age 13 or younger (OR = 0.7; 95% CI: 0.5-1.0). CONCLUSIONS: By examining various anthropometric variables using clinically relevant strata, a clearer picture of how these variables relate to postmenopausal breast cancer risk was developed. Similar to younger women, postmenopausal women who reached their maximum height at later ages had a decreased risk of breast cancer.     

Alcohol and breast cancer in an area with high alcohol consumption

The association between alcohol drinking and breast cancer risk was investigated in 132 breast cancer cases and 499 controls with acute conditions unrelated to alcohol or any of the suspected risk factors for breast cancer, in an area which shows among the highest levels of alcohol consumption and prevalence of alcohol-related diseases in Europe (i.e. Pordenone Province, Northeastern part of Italy). Compared with non-drinkers, the multivariate odds ratio (OR) for ever drinkers was 1.5 (95% confidence interval, CI: 0.8-2.6). The risks for wine (the almost exclusive source of alcohol in the present investigation) were 1.2 for up to 1 drink, 1.4 for up to two drinks, 1.9 for up to 3 and 1.6 for over 3 drinks per day. Time-related factors (i.e. drinking habit duration and age at start of drinking) did not seem to be risk indicators.     

The proportion of cancer attributable to alcohol consumption

Existing evidence leaves little room for doubt that alcoholic beverages are carcinogenic. Alcohol is a risk factor for cancer of the oral cavity, larynx, esophagus, and possibly the liver. The extent to which carcinogenicity is attributable to the alcohol per se, or to other components of some or all of the beverages that contain it, is unclear. The alcohol effect, at least for cancers of the upper aerodigestive tract, depends on tobacco consumption. About 3% of all U.S. cancers in 1974 are attributable to alcohol; the small proportion and the dependence on tobacco mitigate against antidrinking campaigns for the primary prevention of cancer. It is likely that antismoking campaigns would be more effective than antidrinking campaigns in preventing alcohol-related cancers.     

Alcohol consumption and breast cancer risk in the Women's Health Study

The authors assessed the association between moderate alcohol consumption and breast cancer risk in the Women's Health Study (United States, 1992-2004). During an average of 10 years of follow-up, 1,484 cases of total breast cancer (1,190 invasive and 294 in situ) were documented among 38,454 women who, at baseline, were free of cancer and cardiovascular disease and provided detailed dietary information, including alcohol consumption, for the preceding 12 months. Higher alcohol consumption was associated with a modest increase in breast cancer risk; the multivariable relative risks for > or =30 g/day of alcohol vs. none were 1.32 (95% confidence interval (CI): 0.96, 1.82) for total breast cancer and 1.43 (95% CI: 1.02, 2.02) for invasive breast cancer. An increased risk was limited to estrogen receptor (ER)- and progesterone receptor (PR)-positive tumors; the multivariable relative risks for an increment of 10 g/day of alcohol were 1.11 (95% CI: 1.03, 1.20) for ER+PR+ tumors (804 cases), 1.00 (95% CI: 0.81, 1.24) for ER+PR- tumors (125 cases), and 0.99 (95% CI: 0.82, 1.20) for ER-PR- tumors (167 cases). The association also seemed strongest among those taking postmenopausal hormones currently, but the test for interaction was not significant. The findings from this prospective study suggest that moderate alcohol consumption increases breast cancer risk.     

Lactation and cancer risk: is there a relation specific to breast cancer?

Relations between previous lactation experience and risks of cancer of the breast and other sites were investigated after follow-up of 50,274 parous women from 1961 through 1980. Among women with complete information on lactation, 5102 developed cancer and, of these, 1136 were diagnosed with breast cancer. Analyses of associations with mean duration of lactation per birth and duration for each of the three first births suggested a nonlinear relation to breast cancer. The highest risk was observed for those with intermediate duration of breast feeding, whereas lower risks were found among those with very short or very long duration. For all nongenital cancers combined, decreased risks were observed among those with the longest duration of breast feeding. However, among cancers of specific sites, a significant inverse association was found for pancreatic cancer only. The overall impression given by our data is that breast feeding is not strongly related to risks of breast cancer or any other common cancer.     

Predictors of perceived breast cancer risk and the relation between perceived risk and breast cancer screening: a meta-analytic review

BACKGROUND: Perceived risk is a principal variable in theoretical models that attempt to predict the adoption of health-protective behaviors. METHODS: This meta-analysis synthesizes findings from 42 studies, identified in PubMed and PsycInfo from 1985 onward. Studies examined demographic and psychological variables as predictors of perceived breast cancer risk and the relationship between perceived risk and breast cancer screening. Statistical relationships, weighted for sample size, were transformed to effect sizes and 95% CIs. RESULTS: Women do not have accurate perceptions of their breast cancer risk (N = 5561, g = 1.10). Overall, they have an optimistic bias about their personal risk (g = 0.99). However, having a positive family history (N = 70660, g = 0.88), recruitment site, and measurement error confounded these results. Perceived risk is weakly influenced by age (N = 38000, g = 0.13) and education (N = 1979, g = 0.16), and is moderately affected by race/culture (N = 2192, g = 0.38) and worry (N = 6090, g = 0.49). There is an association between perceived risk and mammography screening (N = 52766, g = 0.19). It is not clear whether perceived risk influences adherence to breast self-examination. Women who perceived a higher breast cancer risk were more likely to pursue genetic testing or undergo prophylactic mastectomy. CONCLUSION: Perceived breast cancer risk depends on psychological and cognitive variables and influences adherence to mammography screening guidelines.