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Nabila S, Choi JY, Abe SK, Islam MR, Rahman MS, Saito E, Shin A, Merritt MA, Katagiri R, Shu XO, Sawada N, Tamakoshi A, Sakata R, Hozawa A, Kim J, Nagata C, Park SK, Kweon SS, Cai H, Tsugane S, Kimura T, Kanemura S, Sugawara Y, Wada K, Shin MH, Ahsan H, Boffetta P, Chia KS, Matsuo K, Qiao YL, Rothman N, Zheng W, Inoue M, Kang D. Differential patterns of reproductive and lifestyle risk factors for breast cancer according to birth cohorts among women in China, Japan and Korea. Breast Cancer Res 2024; 26:15. [PMID: 38254178 PMCID: PMC10801993 DOI: 10.1186/s13058-024-01766-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 01/08/2024] [Indexed: 01/24/2024] Open
Abstract
BACKGROUND The birth cohort effect has been suggested to influence the rate of breast cancer incidence and the trends of associated reproductive and lifestyle factors. We conducted a cohort study to determine whether a differential pattern of associations exists between certain factors and breast cancer risk based on birth cohorts. METHODS This was a cohort study using pooled data from 12 cohort studies. We analysed associations between reproductive (menarche age, menopause age, parity and age at first delivery) and lifestyle (smoking and alcohol consumption) factors and breast cancer risk. We obtained hazard ratios (HRs) with 95% confidence intervals (CIs) using the Cox proportional hazard regression analysis on the 1920s, 1930s, 1940s and 1950s birth cohorts. RESULTS Parity was found to lower the risk of breast cancer in the older but not in the younger birth cohort, whereas lifestyle factors showed associations with breast cancer risk only among the participants born in the 1950s. In the younger birth cohort group, the effect size was lower for parous women compared to the other cohort groups (HR [95% CI] 0.86 [0.66-1.13] compared to 0.60 [0.49-0.73], 0.46 [0.38-0.56] and 0.62 [0.51-0.77]). Meanwhile, a higher effect size was found for smoking (1.45 [1.14-1.84] compared to 1.25 [0.99-1.58], 1.06 [0.85-1.32] and 0.86 [0.69-1.08]) and alcohol consumption (1.22 [1.01-1.48] compared to 1.10 [0.90-1.33], 1.15 [0.96-1.38], and 1.07 [0.91-1.26]). CONCLUSION We observed different associations of parity, smoking and alcohol consumption with breast cancer risk across various birth cohorts.
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Grants
- R37 CA070867 NCI NIH HHS
- UM1 CA182910 NCI NIH HHS
- Ministry of Education of the Republic of Korea and the National Research Foundation of Korea
- Korea Multi-Center Cancer Cohort Study, National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning
- Shanghai Women’s Health Study, US National Cancer Institute
- Japan Public Health Center-Based Prospective Study (1 and 2), National Cancer Center Research and Development Fund
- Japan Collaborative Cohort Study, National Cancer Center Research and Development Fund (a grant-in-aid for cancer research)
- Life Span Study Cohort–Radiation Effects Research Foundation, The Japanese Ministry of Health, Labour and Welfare and the US Department of Energy
- Ohsaki National Health Insurance Cohort Study, National Cancer Center Research and Development Fund
- Korea National Cancer Center Cohort, National Cancer Center Research Grant
- Takayama Study, National Cancer Center Research and Development Fund
- The Namwon Study, Chonnam National University Hwasun Hospital Research grant
- Miyagi Cohort Study, National Cancer Center Research and Development Fund
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Affiliation(s)
- Salma Nabila
- Department of Biomedical Sciences, Seoul National University Graduate School, 103 Daehak-ro, Jongno-gu, 03080, Seoul, Republic of Korea
- BK21plus Biomedical Science Project, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ji-Yeob Choi
- Department of Biomedical Sciences, Seoul National University Graduate School, 103 Daehak-ro, Jongno-gu, 03080, Seoul, Republic of Korea.
- BK21plus Biomedical Science Project, Seoul National University College of Medicine, Seoul, Republic of Korea.
- Institute of Health Policy and Management, Seoul National University Medical Research Center, Seoul, Republic of Korea.
- Cancer Research Institute, Seoul National University, Seoul, Republic of Korea.
| | - Sarah Krull Abe
- Division of Prevention, National Cancer Center Institute for Cancer Control, Tokyo, Japan
| | - Md Rashedul Islam
- Division of Prevention, National Cancer Center Institute for Cancer Control, Tokyo, Japan
- Hitotsubashi Institute for Advanced Study, Hitotsubashi University, Tokyo, Japan
| | - Md Shafiur Rahman
- Division of Prevention, National Cancer Center Institute for Cancer Control, Tokyo, Japan
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Eiko Saito
- National Center for Global Health and Medicine, Institute for Global Health Policy Research, Tokyo, Japan
| | - Aesun Shin
- Cancer Research Institute, Seoul National University, Seoul, Republic of Korea
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Melissa A Merritt
- The Daffodil Centre, The University of Sydney, A Joint Venture with Cancer Council NSW, Sydney, Australia
| | - Ryoko Katagiri
- Division of Cohort Research, National Cancer Center Institute for Cancer Control, Tokyo, Japan
- National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan
| | - Xiao-Ou Shu
- Division of Epidemiology, Vanderbilt-Ingram Cancer Center, Vanderbilt Epidemiology Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Norie Sawada
- Division of Cohort Research, National Cancer Center Institute for Cancer Control, Tokyo, Japan
| | - Akiko Tamakoshi
- Department of Public Health, Faculty of Medicine, Hokkaido University, Sapporo, Japan
| | - Ritsu Sakata
- Radiation Effects Research Foundation, Hiroshima, Japan
| | - Atsushi Hozawa
- Tohoku University Graduate School of Medicine, Sendai, Miyagi Prefecture, Japan
| | - Jeongseon Kim
- Graduate School of Cancer Science and Policy, National Cancer Center, Goyang-si, Gyeonggi-do, Republic of Korea
| | - Chisato Nagata
- Department of Epidemiology and Preventive Medicine, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Sue K Park
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sun-Seog Kweon
- Department of Preventive Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Hui Cai
- Division of Epidemiology, Vanderbilt-Ingram Cancer Center, Vanderbilt Epidemiology Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Shoichiro Tsugane
- Division of Cohort Research, National Cancer Center Institute for Cancer Control, Tokyo, Japan
- National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan
| | - Takashi Kimura
- Department of Public Health, Faculty of Medicine, Hokkaido University, Sapporo, Japan
| | - Seiki Kanemura
- Tohoku University Graduate School of Medicine, Sendai, Miyagi Prefecture, Japan
| | - Yumi Sugawara
- Tohoku University Graduate School of Medicine, Sendai, Miyagi Prefecture, Japan
| | - Keiko Wada
- Department of Epidemiology and Preventive Medicine, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Min-Ho Shin
- Department of Preventive Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Habibul Ahsan
- Department of Public Health Sciences, University of Chicago, Chicago, IL, USA
| | - Paolo Boffetta
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Kee Seng Chia
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Keitaro Matsuo
- Division Cancer Epidemiology and Prevention, Aichi Cancer Center Research Institute, Nagoya, Japan
- Department of Cancer Epidemiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - You-Lin Qiao
- School of Population Medicine and Public Health, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Nathaniel Rothman
- Division of Cancer Epidemiology and Genetics, Occupational and Environmental Epidemiology Branch, National Cancer Institute, Bethesda, MD, USA
| | - Wei Zheng
- Division of Epidemiology, Vanderbilt-Ingram Cancer Center, Vanderbilt Epidemiology Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manami Inoue
- Division of Prevention, National Cancer Center Institute for Cancer Control, Tokyo, Japan
| | - Daehee Kang
- Cancer Research Institute, Seoul National University, Seoul, Republic of Korea
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
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2
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Pakzad R, Nedjat S, Salehiniya H, Mansournia N, Etminan M, Nazemipour M, Pakzad I, Mansournia MA. Effect of alcohol consumption on breast cancer: probabilistic bias analysis for adjustment of exposure misclassification bias and confounders. BMC Med Res Methodol 2023; 23:157. [PMID: 37403100 PMCID: PMC10318777 DOI: 10.1186/s12874-023-01978-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 06/15/2023] [Indexed: 07/06/2023] Open
Abstract
PURPOSE This study was conducted to evaluate the effect of alcohol consumption on breast cancer, adjusting for alcohol consumption misclassification bias and confounders. METHODS This was a case-control study of 932 women with breast cancer and 1000 healthy control. Using probabilistic bias analysis method, the association between alcohol consumption and breast cancer was adjusted for the misclassification bias of alcohol consumption as well as a minimally sufficient set of adjustment of confounders derived from a causal directed acyclic graph. Population attributable fraction was estimated using the Miettinen's Formula. RESULTS Based on the conventional logistic regression model, the odds ratio estimate between alcohol consumption and breast cancer was 1.05 (95% CI: 0.57, 1.91). However, the adjusted estimates of odds ratio based on the probabilistic bias analysis ranged from 1.82 to 2.29 for non-differential and from 1.93 to 5.67 for differential misclassification. Population attributable fraction ranged from 1.51 to 2.57% using non-differential bias analysis and 1.54-3.56% based on differential bias analysis. CONCLUSION A marked measurement error was in self-reported alcohol consumption so after correcting misclassification bias, no evidence against independence between alcohol consumption and breast cancer changed to a substantial positive association.
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Affiliation(s)
- Reza Pakzad
- Department of Epidemiology, Faculty of Health, Ilam University of Medical Sciences, Ilam, Iran
- Student Research Committee, Ilam University of Medical Sciences, Ilam, Iran
| | - Saharnaz Nedjat
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, PO Box: 14155-6446, Tehran, Iran
| | - Hamid Salehiniya
- Department of Epidemiology and Biostatistics, School of Health, Birjand University of Medical Sciences, South Khorasan, Iran
| | - Nasrin Mansournia
- Department of Endocrinology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Mahyar Etminan
- Departments of Ophthalmology and Visual Sciences, Medicine and Pharmacology, University of British Columbia, Vancouver, Canada
| | - Maryam Nazemipour
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, PO Box: 14155-6446, Tehran, Iran
| | - Iraj Pakzad
- Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Mohammad Ali Mansournia
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, PO Box: 14155-6446, Tehran, Iran.
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3
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Chu L, Ioannidis JPA, Egilman AC, Vasiliou V, Ross JS, Wallach JD. Vibration of effects in epidemiologic studies of alcohol consumption and breast cancer risk. Int J Epidemiol 2021; 49:608-618. [PMID: 31967637 DOI: 10.1093/ije/dyz271] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 11/27/2019] [Accepted: 12/06/2019] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Different analytical approaches can influence the associations estimated in observational studies. We assessed the variability of effect estimates reported within and across observational studies evaluating the impact of alcohol on breast cancer. METHODS We abstracted largest harmful, largest protective and smallest (closest to the null value of 1.0) relative risk estimates in studies included in a recent alcohol-breast cancer meta-analysis, and recorded how they differed based on five model specification characteristics, including exposure definition, exposure contrast levels, study populations, adjustment covariates and/or model approaches. For each study, we approximated vibration of effects by dividing the largest by the smallest effect estimate [i.e. ratio of odds ratio (ROR)]. RESULTS Among 97 eligible studies, 85 (87.6%) reported both harmful and protective relative effect estimates for an alcohol-breast cancer relationship, which ranged from 1.1 to 17.9 and 0.0 to 1.0, respectively. The RORs comparing the largest and smallest estimates in value ranged from 1.0 to 106.2, with a median of 3.0 [interquartile range (IQR) 2.0-5.2]. One-third (35, 36.1%) of the RORs were based on extreme effect estimates with at least three different model specification characteristics; the vast majority (87, 89.7%) had different exposure definitions or contrast levels. Similar vibrations of effect were observed when only extreme estimates with differences based on study populations and/or adjustment covariates were compared. CONCLUSIONS Most observational studies evaluating the impact of alcohol on breast cancer report relative effect estimates for the same associations that diverge by >2-fold. Therefore, observational studies should estimate the vibration of effects to provide insight regarding the stability of findings.
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Affiliation(s)
- Lingzhi Chu
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT, USA
| | - John P A Ioannidis
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, USA.,Department of Health Research and Policy, Stanford University School of Medicine, Stanford, CA, USA.,Stanford Prevention Research Center, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.,Department of Statistics, Stanford University School of Humanities and Sciences, Stanford, CA, USA
| | - Alex C Egilman
- Collaboration for Research Integrity and Transparency (CRIT), Yale Law School, New Haven, CT, USA
| | - Vasilis Vasiliou
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT, USA
| | - Joseph S Ross
- Section of General Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA.,National Clinician Scholars Program, Yale School of Medicine, New Haven, CT, USA.,Department of Health Policy and Management, Yale School of Public Health, New Haven, CT, USA.,Center for Outcomes Research and Evaluation, Yale-New Haven Health System, New Haven, CT, USA
| | - Joshua D Wallach
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT, USA.,Collaboration for Research Integrity and Transparency (CRIT), Yale Law School, New Haven, CT, USA
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4
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Iwase M, Matsuo K, Koyanagi YNY, Ito H, Tamakoshi A, Wang C, Utada M, Ozasa K, Sugawara Y, Tsuji I, Sawada N, Tanaka S, Nagata C, Kitamura Y, Shimazu T, Mizoue T, Naito M, Tanaka K, Inoue M. Alcohol consumption and breast cancer risk in Japan: A pooled analysis of eight population-based cohort studies. Int J Cancer 2021; 148:2736-2747. [PMID: 33497475 DOI: 10.1002/ijc.33478] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 01/22/2023]
Abstract
Although alcohol consumption is reported to increase the incidence of breast cancer in European studies, evidence for an association between alcohol and breast cancer in Asian populations is insufficient. We conducted a pooled analysis of eight large-scale population-based prospective cohort studies in Japan to evaluate the association between alcohol (both frequency and amount) and breast cancer risk with categorization by menopausal status at baseline and at diagnosis. Estimated hazard ratios (HR) and 95% confidence intervals were calculated in the individual cohorts and combined using random-effects models. Among 158 164 subjects with 2 369 252 person-years of follow-up, 2208 breast cancer cases were newly diagnosed. Alcohol consumption had a significant association with a higher risk of breast cancer in both women who were premenopausal at baseline (regular drinker compared to nondrinker: HR 1.37, 1.04-1.81, ≥23 g/d compared to 0 g/d: HR 1.74, 1.25-2.43, P for trend per frequency category: P = .017) and those who were premenopausal at diagnosis (≥23 g/d compared to 0 g/d: HR 1.89, 1.04-3.43, P for trend per frequency category: P = .032). In contrast, no significant association was seen in women who were postmenopausal at baseline or at diagnosis, despite a substantial number of subjects and long follow-up period. Our results revealed that frequent and high alcohol consumption are both risk factors for Asian premenopausal breast cancer, similarly to previous studies in Western countries. The lack of a clear association in postmenopausal women in our study warrants larger investigation in Asia.
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Affiliation(s)
- Madoka Iwase
- Division of Cancer Epidemiology and Prevention, Aichi Cancer Center Research Institute, Nagoya, Japan.,Department of Surgical Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Keitaro Matsuo
- Division of Cancer Epidemiology and Prevention, Aichi Cancer Center Research Institute, Nagoya, Japan.,Division of Cancer Epidemiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuriko N Y Koyanagi
- Division of Cancer Information and Control, Aichi Cancer Center Research Institute, Nagoya, Japan
| | - Hidemi Ito
- Division of Cancer Information and Control, Aichi Cancer Center Research Institute, Nagoya, Japan.,Division of Descriptive Cancer Epidemiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akiko Tamakoshi
- Department of Public Health, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Chaochen Wang
- Department of Public Health, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Mai Utada
- Department of Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Kotaro Ozasa
- Department of Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Yumi Sugawara
- Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Ichiro Tsuji
- Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Norie Sawada
- Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan
| | - Shiori Tanaka
- Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan
| | - Chisato Nagata
- Department of Epidemiology and Preventive Medicine, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Yuri Kitamura
- Department of Social and Environmental Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Taichi Shimazu
- Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan
| | - Tetsuya Mizoue
- Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan
| | - Mariko Naito
- Department of Oral Epidemiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Keitaro Tanaka
- Department of Preventive Medicine, Faculty of Medicine, Saga University, Saga, Japan
| | - Manami Inoue
- Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.,Department of Cancer Epidemiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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5
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Abstract
Globally, more than 2 million new cases of breast cancer are reported annually. The United States alone has more than 496,000 new cases every year. The worldwide prevalence is approximately 6.8 million cases. Although many risk factors for breast cancer are not modifiable, understanding the role of the factors that can be altered is critical. Alcohol consumption is a modifiable factor. Studies of alcohol in relation to breast cancer incidence have included hundreds of thousands of women. Evidence is consistent that intake, even intake of less than 10–15 grams per day, is associated with increased risk of this disease. In addition, evidence, although less extensive, shows that possible early indicators of risk, such as benign breast disease and increased breast density, are associated with alcohol consumption. Evidence is less strong for differences based on geographic region, beverage type, drinking pattern, or breast cancer subtype. Some studies have examined the association between alcohol and recurrence or survival after a breast cancer diagnosis. These findings are less consistent. Public awareness of alcohol as a risk factor for breast cancer is low, and public health measures to increase that awareness are warranted.
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Affiliation(s)
- Jo L Freudenheim
- School of Public Health and Health Professions, University at Buffalo, Buffalo, New York
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6
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Chu L, Wallach JD. Consideration of confounding in epidemiologic studies assessing alcohol consumption on the risk of breast cancer: A brief report. Chem Biol Interact 2020; 322:109060. [PMID: 32171849 DOI: 10.1016/j.cbi.2020.109060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 03/10/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Individual observational studies have suggested null, weak, linear, and J-shaped associations between alcohol consumption and breast cancer risk. However, observational studies are susceptible to confounders, which can obscure the true impact of an exposure on an outcome. Given the uncertainty regarding the association between alcohol consumption and breast cancer, and the challenges of identifying, measuring, and accounting for all potential confounders, we assessed whether and how authors of observational studies evaluating the impact of alcohol consumption on the risk of breast cancer considered bias when interpreting their main study findings. METHODS We identified all observational studies included in a recent alcohol-breast cancer meta-analysis. The Abstract and/or Discussion sections were reviewed to determine whether authors considered confounding. RESULTS Among 101 eligible studies, 73 (72.3%) mentioned confounding explicitly in the Abstract and Discussion sections. There were 33 (32.7%) studies that included statements regarding specific confounders that were not adjusted for in the analyses and 60 (59.4%) studies without any statements about the impact of residual confounding on their main findings. Although none of the studies outlined that their main findings were "likely" to be affected by residual confounding, 25 (24.8%) mentioned a "possible" impact and 16 (15.8%) claimed an "unlikely" impact. Only one (1.0%) article explicitly stated that caution was needed when interpreting their findings due to confounding. CONCLUSION These results highlight the need for more adequate consideration of the potential impact of residual confounding in observational studies evaluating the impact of alcohol consumption on the risk of breast cancer.
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Affiliation(s)
- Lingzhi Chu
- Department of Environmental Health Sciences, Yale School of Public Health, 60 College Street, 4th Floor, 411, New Haven, CT, 06510, USA
| | - Joshua D Wallach
- Department of Environmental Health Sciences, Yale School of Public Health, 60 College Street, 4th Floor, 411, New Haven, CT, 06510, USA; Collaboration for Research Integrity and Transparency (CRIT), Yale School of Medicine, 157 Church Street, 17th Floor, Suite 1, New Haven, CT, 06510, USA; Center for Outcomes Research and Evaluation, Yale-New Haven Health System, New Haven, CT, 06510, USA.
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7
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Zaitsu M, Takeuchi T, Kobayashi Y, Kawachi I. Light to moderate amount of lifetime alcohol consumption and risk of cancer in Japan. Cancer 2019; 126:1031-1040. [PMID: 31814116 PMCID: PMC7027900 DOI: 10.1002/cncr.32590] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/27/2019] [Accepted: 10/03/2019] [Indexed: 12/15/2022]
Abstract
BACKGROUND Even light to moderate alcohol consumption has been shown to increase cancer incidence. However, this association has not been well characterized in Japan. METHODS Based on a nationwide, hospital-based data set (2005-2016), a multicenter case-control study was conducted (63,232 cancer cases and 63,232 controls matched for sex, age, admission date, and admitting hospital). The total amount of lifetime alcohol consumption (drink-years) was recalled for each patient by multiplication of the daily amount of standardized alcohol use (drinks per day) and the duration of drinking (years). Odds ratios (ORs) were estimated for overall and specific cancer sites via conditional logistic regression with restricted cubic splines, with adjustments made for smoking, occupational class, and comorbidities. Lifetime abstainers served as the reference group. RESULTS Spline curves showed a dose-response association with overall cancer risk: the minimum risk was at 0 drink-years, and the OR at 10 drink-years was 1.05 (95% confidence interval [CI], 1.04-1.06). In comparison with lifetime abstainers, the OR for >0 to 20 drink-years was 1.06 (95% CI, 1.01-1.11). Those who drank 2 drinks or fewer per day had elevated odds for overall cancer risk across all duration-of-drinking categories. The same patterns were observed at light to moderate levels of drinking for most gastrointestinal/aerodigestive cancers as well as breast and prostate cancers. Analyses stratified by sex, different drinking/smoking behaviors, and occupational class mostly showed the same patterns for overall cancer incidence associated with light to moderate levels of drinking. CONCLUSIONS In Japan, even light to moderate alcohol consumption appears to be associated with elevated cancer risks.
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Affiliation(s)
- Masayoshi Zaitsu
- Department of Public Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.,Department of Social and Behavioral Sciences, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
| | - Takumi Takeuchi
- Department of Urology, Kanto Rosai Hospital, Kawasaki, Japan
| | - Yasuki Kobayashi
- Department of Public Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ichiro Kawachi
- Department of Social and Behavioral Sciences, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
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8
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Minami Y, Kanemura S, Kawai M, Nishino Y, Tada H, Miyashita M, Ishida T, Kakugawa Y. Alcohol consumption and survival after breast cancer diagnosis in Japanese women: A prospective patient cohort study. PLoS One 2019; 14:e0224797. [PMID: 31721806 PMCID: PMC6853331 DOI: 10.1371/journal.pone.0224797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/10/2019] [Indexed: 01/14/2023] Open
Abstract
Background It is unclear whether alcohol consumption may impact survival after breast cancer diagnosis. To clarify the association between pretreatment alcohol consumption and survival in breast cancer patients, a prospective patient cohort study was conducted. Methods The cohort comprised 1,420 breast cancer patients diagnosed during 1997–2013 at a single institute in Japan. Alcohol drinking and other lifestyle factors were assessed by questionnaire survey at the initial admission. The patients were followed until December 31, 2016. The crude associations of pretreatment alcohol intake with survival were evaluated by Kaplan-Meier analysis. The Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) controlled by confounders. Results During a median follow-up period of 8.6 years, 261 all-cause and 193 breast cancer-specific deaths were documented. Survival curves showed that ever-drinkers tended to have better survival than never-drinkers (breast cancer-specific survival, log-rank p = 0.0381). Better survival was also observed for light drinkers with an intake of <5.0 g per day. In the Cox model, ever-drinking was associated with a decreased risk of all-cause (HR: 0.75; 95% CI: 0.54–1.05) and breast cancer-specific death (HR: 0.68; 95% CI: 0.46–0.99). Light drinkers had a lower risk of breast cancer-specific death (frequency of drinking, HR = 0.57 for occasional or 1–2 times per week and 0.72 for 3–7 times per week; amount of alcohol consumed per day, HR = 0.57 for <5.0 g and 0.68 for ≥5.0 g compared with never-drinking). In terms of hormone receptor status, a significantly decreased risk of death associated with ever-drinking was observed among women with receptor-negative cancer (ER-/PR-, HR = 0.41; 95% CI: 0.20–0.84 for breast cancer-specific death). Conclusions Pretreatment, i.e., pre-diagnosis alcohol consumption is unlikely to have an adverse effect on survival after breast cancer diagnosis. Light alcohol consumption may have a beneficial effect on patient survival.
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Affiliation(s)
- Yuko Minami
- Division of Community Health, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Division of Cancer Epidemiology and Prevention, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan
- Center for Preventive Medicine, Osaki Citizen Hospital, Osaki, Miyagi, Japan
- * E-mail:
| | - Seiki Kanemura
- Division of Cancer Epidemiology and Prevention, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan
| | - Masaaki Kawai
- Department of Breast Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Yoshikazu Nishino
- Division of Cancer Epidemiology and Prevention, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan
- Department of Epidemiology and Public Health, Kanazawa Medical University, 1–1 Daigaku, Uchinada, Kahoku, Ishikawa, Japan
| | - Hiroshi Tada
- Department of Breast Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Minoru Miyashita
- Department of Breast and Endocrine Surgical Oncology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Takanori Ishida
- Department of Breast and Endocrine Surgical Oncology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Yoichiro Kakugawa
- Department of Breast Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
- Department of Surgery, Japanese Red Cross Sendai Hospital, Sendai, Miyagi, Japan
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9
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Mukherjee S, Sonanini D, Maurer A, Daldrup-Link HE. The yin and yang of imaging tumor associated macrophages with PET and MRI. Am J Cancer Res 2019; 9:7730-7748. [PMID: 31695797 PMCID: PMC6831464 DOI: 10.7150/thno.37306] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/27/2019] [Indexed: 12/14/2022] Open
Abstract
Tumor associated macrophages (TAM) are key players in the cancer microenvironment. Molecular imaging modalities such as MRI and PET can be used to track and monitor TAM dynamics in tumors non-invasively, based on specific uptake and quantification of MRI-detectable nanoparticles or PET-detectable radiotracers. Particular molecular signatures can be leveraged to target anti-inflammatory TAM, which support tumor growth, and pro-inflammatory TAM, which suppress tumor growth. In addition, TAM-directed imaging probes can be designed to include immune modulating properties, thereby leading to combined diagnostic and therapeutic (theranostic) effects. In this review, we will discuss the complementary role of TAM-directed radiotracers and iron oxide nanoparticles for monitoring cancer immunotherapies with PET and MRI technologies. In addition, we will outline how TAM-directed imaging and therapy is interdependent and can be connected towards improved clinical outcomes
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10
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Zakhari S, Hoek JB. Epidemiology of Moderate Alcohol Consumption and Breast Cancer: Association or Causation? Cancers (Basel) 2018; 10:E349. [PMID: 30249004 PMCID: PMC6210419 DOI: 10.3390/cancers10100349] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 09/20/2018] [Accepted: 09/20/2018] [Indexed: 02/07/2023] Open
Abstract
Epidemiological studies have been used to show associations between modifiable lifestyle habits and the incidence of breast cancer. Among such factors, a history of alcohol use has been reported in multiple studies and meta-analyses over the past decades. However, associative epidemiological studies that were interpreted as evidence that even moderate alcohol consumption increases breast cancer incidence have been controversial. In this review, we consider the literature on the relationship between moderate or heavy alcohol use, both in possible biological mechanisms and in variations in susceptibility due to genetic or epigenetic factors. We argue that there is a need to incorporate additional approaches to move beyond the associations that are reported in traditional epidemiological analyses and incorporate information on molecular pathologic signatures as a requirement to posit causal inferences. In particular, we point to the efforts of the transdisciplinary field of molecular pathological epidemiology (MPE) to evaluate possible causal relationships, if any, of alcohol consumption and breast cancer. A wider application of the principles of MPE to this field would constitute a giant step that could enhance our understanding of breast cancer and multiple modifiable risk factors, a step that would be particularly suited to the era of "personalized medicine".
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Affiliation(s)
- Samir Zakhari
- Science Office, Distilled Spirits Council, Washington, DC 20005, USA.
| | - Jan B Hoek
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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11
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Minami Y, Kanemura S, Oikawa T, Suzuki S, Hasegawa Y, Miura K, Nishino Y, Kakugawa Y, Fujiya T. Associations of cigarette smoking and alcohol drinking with stomach cancer survival: A prospective patient cohort study in Japan. Int J Cancer 2018; 143:1072-1085. [PMID: 29603213 DOI: 10.1002/ijc.31408] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 12/16/2022]
Abstract
Cigarette smoking and alcohol drinking may affect the prognosis of stomach cancer, but evidence has been inconsistent. We investigated the associations between pretreatment smoking and alcohol drinking and the risk of all-cause and stomach cancer death among 1,576 patients with histologically confirmed stomach cancer diagnosed during 1997-2010 at a single hospital in Japan. Histories of smoking and alcohol drinking were assessed using a self-administered questionnaire. The patients were followed until December 31, 2013. The Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During 9,625.1 person-years, 670 all-cause and 419 stomach cancer deaths were documented. Among the patients overall, ever-drinking was significantly associated with an increased risk of all-cause death (HR: 1.25; 95% CI: 1.03-1.51), but not stomach cancer death. Positive linear associations with the frequency of drinking (ptrend = 0.02) and the amount of alcohol consumed per day (ptrend = 0.03) were observed for the risk of all-cause death. Ever-smoking was not related to either the risk of all-cause or stomach cancer death. Conversely, among the patients who underwent curative resection, a significant positive association was found between ever-smoking and the risk of stomach cancer death (HR: 2.44; 95% CI: 1.17-5.08). A positive association was also found for earlier age at start of smoking (ptrend = 0.0046). Pretreatment smoking and alcohol drinking have significant effects on stomach cancer survival. Lifestyle adjustments throughout life may improve survival.
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Affiliation(s)
- Yuko Minami
- Division of Community Health, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.,Division of Cancer Epidemiology and Prevention, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan.,Center for Preventive Medicine, Osaki Citizen Hospital, Furukawa, Osaki, Miyagi, Japan
| | - Seiki Kanemura
- Division of Cancer Epidemiology and Prevention, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan
| | - Tomoyuki Oikawa
- Department of Gastroenterology, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Shinichi Suzuki
- Department of Gastroenterology, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Yasuhiro Hasegawa
- Department of Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Koh Miura
- Department of Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Yoshikazu Nishino
- Department of Epidemiology and Public Health, Kanazawa Medical University, Kahoku, Ishikawa, Japan
| | - Yoichiro Kakugawa
- Department of Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
| | - Tsuneaki Fujiya
- Department of Surgery, Miyagi Cancer Center Hospital, Natori, Miyagi, Japan
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12
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Choi YJ, Myung SK, Lee JH. Light Alcohol Drinking and Risk of Cancer: A Meta-Analysis of Cohort Studies. Cancer Res Treat 2017; 50:474-487. [PMID: 28546524 PMCID: PMC5912140 DOI: 10.4143/crt.2017.094] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/16/2017] [Indexed: 12/13/2022] Open
Abstract
Purpose The purpose of this study was to determine whether light alcohol drinking increases the risk of cancer by using a meta-analysis of cohort studies because the newly revised 2015 European Code against Cancer fourth edition on alcohol and cancer was based on critical flaws in the interpretation and citation of the previous meta-analyses. Materials and Methods PubMed and EMBASE were searched in April, 2016. Two authors independently reviewed and selected cohort studies on the association between very light (≤ 0.5 drink/day), light (≤ 1 drink/day), or moderate drinking (1-2 drinks/day) and the risk of cancer incidence and mortality. A pooled relative riskwith its 95% confidence intervalwas calculated by a random-effects meta-analysis. Main outcome measures were cancer incidence and mortality. Results A total of 60 cohort studies from 135 articles were included in the final analysis. Very light drinking or light drinking was not associated with the incidence of most cancers except for female breast cancer in women and male colorectal cancer. Conversely, light drinking was associated with a decreased incidence of both female and male lung cancer significantly and both female and male thyroid cancer marginally significantly. Moderate drinking significantly increased the incidence of male colorectal cancer and female breast cancer,whereas it decreased the incidence of both female and male hematologic malignancy. Conclusion We found that very light or light alcohol drinking was not associated with the risk of most of the common cancers except for the mild increase in the incidence of breast cancer in women and colorectal cancer in men.
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Affiliation(s)
- Yoon-Jung Choi
- Department of Family Medicine and Center for Cancer Prevention and Detection, Hospital, National Cancer Center, Goyang, Korea
| | - Seung-Kwon Myung
- Department of Family Medicine and Center for Cancer Prevention and Detection, Hospital, National Cancer Center, Goyang, Korea.,Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy, Goyang, Korea.,Cancer Epidemiology Branch, Division of Cancer Epidemiology and Prevention, Research Institute, National Cancer Center, Goyang, Korea
| | - Ji-Ho Lee
- Department of Family Medicine and Center for Cancer Prevention and Detection, Hospital, National Cancer Center, Goyang, Korea
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13
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The Japanese Breast Cancer Society clinical practice guidelines for epidemiology and prevention of breast cancer, 2015 edition. Breast Cancer 2016; 23:343-56. [DOI: 10.1007/s12282-016-0673-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 12/27/2015] [Indexed: 12/13/2022]
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14
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de Menezes RF, Bergmann A, de Aguiar SS, Thuler LCS. Alcohol consumption and the risk of cancer in Brazil: A study involving 203,506 cancer patients. Alcohol 2015; 49:747-51. [PMID: 26298519 DOI: 10.1016/j.alcohol.2015.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 07/05/2015] [Accepted: 07/08/2015] [Indexed: 01/14/2023]
Abstract
This study aims to analyze the association between alcohol consumption and the risk of developing the most common types of cancer in the Brazilian population. It is a case-control study in which the most common types of cancer were considered as cases and non-melanoma skin cancers as controls. Data were routinely obtained by hospital-based cancer registrars. Individuals between 18 and 100 years old, diagnosed between January 1, 2000 and December 31, 2009, with information regarding alcohol consumption, were included. The odds ratio (OR) for each type of cancer was calculated, adjusting for confounding variables. The etiologic fraction (EF) was calculated in cases with statistically significant results. The study included 203,506 individuals (110,550 women and 92,956 men), with an average age of 59 years. A statistically significant association was found between alcohol consumption and increased risk of cancers of the respiratory and digestive systems, prostate, and female breast. The association between alcohol consumption and cancers of the urinary tract, male genital organs, and other neoplasias was not statistically significant. Consumption of alcoholic beverages increased the risk of developing cancer of the nasal cavity, pyriform sinus, oral cavity, oropharynx, nasopharynx, larynx, hypopharynx, lung, esophagus, stomach, liver, pancreas, breast, prostate, colon and rectum, and anus and anal canal.
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Affiliation(s)
| | - Anke Bergmann
- Clinical Epidemiology Program, National Cancer Institute, INCA, Rio de Janeiro, Brazil; Coordination of Education, National Cancer Institute, INCA, Rio de Janeiro, Brazil
| | | | - Luiz Claudio Santos Thuler
- Clinical Epidemiology Program, National Cancer Institute, INCA, Rio de Janeiro, Brazil; Neurology Postgraduate Program, Federal University of Rio de Janeiro State, UNIRIO, Rio de Janeiro, Brazil.
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15
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Anai A, Ueda K, Harada K, Katoh T, Fukumoto K, Wei CN. Determinant factors of the difference between self-reported weight and measured weight among Japanese. Environ Health Prev Med 2015; 20:447-54. [PMID: 26349447 DOI: 10.1007/s12199-015-0489-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 08/10/2015] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES To assess the difference between self-reported and measured weight values in Japanese men and women and to determine the underlying determinants of the differences between self-reported and measured values. METHODS The data were collected from 363 general Japanese individuals aged 16-88 years living in Kumamoto prefecture. Participants completed a self-administered questionnaire designed for this study with self-reported weight and height values. Measured weight and height were measured immediately after questionnaire completion. Paired t-tests identified differences between self-reported and measured values by sex. Multiple-stepwise regression analysis examined the independent variables' effects on the differences between self-reported and measured weights. RESULTS Significant differences were found between self-reported and measured values for both sexes (p < 0.001). There was a significant negative relationship between the difference in an individual's self-reported and measured weight in each sex, with higher measured weight individuals more likely to underestimate their weight. Multiple-stepwise regression analysis models explained 12.1 % (p < 0.01), 11.3 % (p < 0.01), and 5.6 % (p < 0.01) of the variance in all participants, men, and women, respectively. Significant effects were found for age, weight measurement frequency, and measured weight in total participants, weight measurement frequency, and measured weight for men, and age for women. CONCLUSIONS In this study, the mean absolute value of the weight and height variances proved the unreliability of self-reported weight and height values. This study's findings suggest self-reported weight inaccuracy especially for obese populations. This should be adjusted when using it in epidemiological studies and healthcare planning.
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Affiliation(s)
- Akane Anai
- Department of Public Health, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjou, Kumamoto, 860-8556, Japan.
| | - Kimiyo Ueda
- Department of Community Health Nursing, School of Health Science, Kumamoto University, Kumamoto, Japan
| | - Koichi Harada
- Department of Medical Technology, Faculty of Health Science, Kumamoto Health Science University, Kumamoto, Japan
| | - Takahiko Katoh
- Department of Public Health, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjou, Kumamoto, 860-8556, Japan
| | - Kumiko Fukumoto
- Kyushu University of Nursing and Social Welfare, Tomio, Tamana, Japan
| | - Chang-Nian Wei
- Department of Public Health, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjou, Kumamoto, 860-8556, Japan
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16
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Personality and breast cancer risk and survival: the Miyagi cohort study. Breast Cancer Res Treat 2015; 150:675-84. [PMID: 25829230 DOI: 10.1007/s10549-015-3364-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 03/26/2015] [Indexed: 01/21/2023]
Abstract
It has long been hypothesized that personality is associated with breast cancer risk and survival. The present population-based prospective cohort study in Japan tested this hypothesis. To investigate the association of personality with breast cancer risk, a total of 15,107 women aged 40-64 years who completed the Eysenck Personality Questionnaire-Revised (EPQ-R) Short Form were followed from 1990 to 2007. To assess the association of personality with survival after breast cancer, 250 identified cases were further followed up from the date of diagnosis to 2008, and 45 all-cause deaths were documented. Study subjects were categorized into four groups based on the quartile points of scores ranging between 0 and 12 on each EPQ-R subscale (extraversion, neuroticism, psychoticism, and lie), and the hazard ratio (HR) for each category was computed using the lowest category as reference. Multivariate analysis revealed no association between any of the four personality subscales and the risk of breast cancer. In the analysis on survival, no significant association was found between any of these subscales and the risk of death, although breast cancer cases with a higher score of extraversion tended to have a lower risk of death (P for trend = 0.07; HR for highest score level = 0.38). Exclusion of 32 cases diagnosed in the first 3 years of follow-up did not largely change the results with regard to either breast cancer risk or survival. The present findings suggest that personality does not impact significantly on the development and progression of breast cancer.
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17
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Zakhari S, Hoek JB. Alcohol and breast cancer: reconciling epidemiological and molecular data. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 815:7-39. [PMID: 25427899 DOI: 10.1007/978-3-319-09614-8_2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Breast cancer is the most diagnosed cancer in women worldwide. Epidemiological studies have suggested a possible causative role of alcohol consumption as a risk factor for breast cancer. However, such conclusions should be interpreted with considerable caution for several reasons. While epidemiological studies can help identify the roots of health problems and disease incidence in a community, they are by necessity associative and cannot determine cause and effect relationships. In addition, all these studies rely on self-reporting to determine the amount and type of alcoholic beverage consumed, which introduces recall bias. This is documented in a recent study which stated that the apparent increased risk of cancer among light-moderate drinkers may be "substantially due to underreporting of intake." Another meta-analysis about alcohol and breast cancer declared "the modest size of the association and variation in results across studies leave the causal role of alcohol in question." Furthermore, breast cancer develops over decades; thus, correlations between alcohol consumption and breast cancer cannot be determined in epidemiological studies with windows of alcohol exposure that captures current or recent alcohol intake, after clinical diagnosis. Numerous risk factors are involved in breast carcinogenesis; some are genetic and beyond the control of a woman; others are influenced by lifestyle factors. Breast cancer is a heterogeneous and polygenic disease which is further influenced by epigenetic mechanisms that affect the transciptomes, proteomes and metabolomes, and ultimately breast cancer evolution. Environmental factors add another layer of complexity by their interactions with the susceptibility genes for breast cancer and metabolic diseases. The current state-of-knowledge about alcohol and breast cancer association is ambiguous and confusing to both a woman and her physician. Confronting the huge global breast cancer issue should be addressed by sound science. It is advised that women with or without a high risk for breast cancer should avoid overconsumption of alcohol and should consult with their physician about risk factors involved in breast cancer. Since studies associating moderate alcohol consumption and breast cancer are contradictory, a woman and her physician should weigh the risks and benefits of moderate alcohol consumption.
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Affiliation(s)
- Samir Zakhari
- Former Director, Division of Metabolism and Health Effects, NIAAA, NIH, Bethesda, MD, 20852, USA,
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18
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Mourouti N, Kontogianni MD, Papavagelis C, Panagiotakos DB. Diet and breast cancer: a systematic review. Int J Food Sci Nutr 2014; 66:1-42. [DOI: 10.3109/09637486.2014.950207] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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19
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Taira N, Arai M, Ikeda M, Iwasaki M, Okamura H, Takamatsu K, Yamamoto S, Ohsumi S, Mukai H. The Japanese Breast Cancer Society clinical practice guideline for epidemiology and prevention of breast cancer. Breast Cancer 2014; 22:16-27. [DOI: 10.1007/s12282-014-0555-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/14/2014] [Indexed: 12/29/2022]
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20
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Chen P, Li C, Li X, Li J, Chu R, Wang H. Higher dietary folate intake reduces the breast cancer risk: a systematic review and meta-analysis. Br J Cancer 2014; 110:2327-38. [PMID: 24667649 PMCID: PMC4007237 DOI: 10.1038/bjc.2014.155] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/27/2014] [Accepted: 02/28/2014] [Indexed: 01/20/2023] Open
Abstract
Background: Many epidemiological studies have investigated the association between folate intake, circulating folate level and risk of breast cancer; however, the findings were inconsistent between the studies. Methods: We searched the PubMed and MEDLINE databases updated to January, 2014 and performed the systematic review and meta-analysis of the published epidemiological studies to assess the associations between folate intake level, circulating folate level and the overall risk of breast cancer. Results: In all, 16 eligible prospective studies with a total of 744 068 participants and 26 205 breast cancer patients and 26 case–control studies with a total of 16 826 cases and 21 820 controls that have evaluated the association between folate intake and breast cancer risk were identified. Pooled analysis of the prospective studies and case–control studies suggested a potential nonlinearity relationship for dietary folate intake and breast cancer risk. Prospective studies indicated a U-shaped relationship for the dietary folate intake and breast cancer risk. Women with daily dietary folate intake between 153 and 400 μg showed a significant reduced breast cancer risk compared with those <153 μg, but not for those >400 μg. The case–control studies also suggested a significantly negative correlation between the dietary folate intake level and the breast cancer risk. Increased dietary folate intake reduced breast cancer risk for women with higher alcohol intake level, but not for those with lower alcohol intake. No significant association between circulating folate level and breast cancer risk was found when the results of 8 identified studies with 5924 participants were pooled. Conclusions: Our studies suggested that folate may have preventive effects against breast cancer risk, especially for those with higher alcohol consumption level; however, the dose and timing are critical and more studies are warranted to further elucidate the questions.
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Affiliation(s)
- P Chen
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - C Li
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - X Li
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - J Li
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - R Chu
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - H Wang
- 1] Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai 200031, People's Republic of China [2] Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, People's Republic of China [3] School of Life Science and Technology, ShanghaiTech University, Shanghai 200031, People's Republic of China
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Gao Y, Huang YB, Liu XO, Chen C, Dai HJ, Song FJ, Wang J, Chen KX, Wang YG. Tea Consumption, Alcohol Drinking and Physical Activity Associations with Breast Cancer Risk among Chinese Females: a Systematic Review and Meta-analysis. Asian Pac J Cancer Prev 2013; 14:7543-50. [DOI: 10.7314/apjcp.2013.14.12.7543] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abstract
Owing to its interaction with alcohol, folate has been suggested to be a potential factor for many types of cancer. The impact of these factors on the risk of breast cancer among Asian populations has not been fully examined, however, particularly with respect to receptor status. We carried out a case-control study in premenopausal and postmenopausal Japanese women, including 1754 breast cancer patients and 3508 noncancer controls. We determined the association between self-reported alcohol drinking, dietary folate intake, and the risk of breast cancer. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using logistic models adjusted for potential confounders. Alcohol consumption was associated with the risk of breast cancer, with the OR for a drinker consuming 23 g or more per day relative to a nondrinker of 1.39 (95% CI: 1.07-1.80). A significant inverse association was observed between folate intake and overall risk of breast cancer, with an OR of 0.79 (95% CI: 0.68-0.93; Ptrend=0.004) for the highest tertile relative to the lowest. The OR of a drinker consuming 23 g or more per day relative to a nondrinker with a low folate intake was 1.58 (95% CI: 1.06-2.33). However, a significantly increased risk was not observed in tertile 2 and tertile 3 folate in taker with any amount of alcohol consumption. Higher folate intake decreases the risk of breast cancer among Japanese, whereas alcohol intake increases the risk. These two factors interact with each other, and the excess risk of breast cancer with alcohol consumption might be attenuated by increasing the intake of folate. In addition, the effects of folate/alcohol may vary according to the tumor subtype.
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Park SY, Kolonel LN, Lim U, White KK, Henderson BE, Wilkens LR. Alcohol consumption and breast cancer risk among women from five ethnic groups with light to moderate intakes: the Multiethnic Cohort Study. Int J Cancer 2013; 134:1504-10. [PMID: 24037751 DOI: 10.1002/ijc.28476] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 07/24/2013] [Accepted: 08/01/2013] [Indexed: 11/10/2022]
Abstract
Higher alcohol consumption, even at moderate levels, has been associated with an increased risk of breast cancer in epidemiological studies. However, prior studies were conducted in mostly white populations. To assess the relationship of alcohol consumption to postmenopausal breast cancer risk in a multiethnic population of largely never, light or moderate drinkers, we prospectively examined the association in 85,089 women enrolled in the Multiethnic Cohort in Hawaii and California. During a mean follow-up of 12.4 years, 3,885 incident invasive breast cancer cases were identified. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard models, controlling for potential confounders. Higher alcohol consumption was associated with increased risk of breast cancer: compared to nondrinkers, HRs were 1.23 (95% CI: 1.06-1.42), 1.21 (95% CI: 1.00-1.45), 1.12 (95% CI: 0.95-1.31) and 1.53 (95% CI: 1.32-1.77) for 5-9.9, 10-14.9, 15-29.9 and ≥ 30 g/day of alcohol, respectively. The positive association was seen in African American, Japanese American, Latino and white, but not in Native Hawaiian women, and in those with tumors that were both positive and negative for estrogen and progesterone receptors (ER/PR). This prospective study supports previous findings that light to moderate alcohol consumption increases breast cancer risk, and demonstrates this association in several ethnic groups besides whites, independent of ER/PR status.
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Affiliation(s)
- Song-Yi Park
- Cancer Epidemiology Program, University of Hawaii Cancer Center, Honolulu, HI
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Anthropometric factors, physical activity, and breast cancer risk in relation to hormone receptor and menopausal status in Japanese women: a case-control study. Cancer Causes Control 2013; 24:1033-44. [PMID: 23494727 DOI: 10.1007/s10552-013-0181-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Accepted: 02/23/2013] [Indexed: 01/18/2023]
Abstract
PURPOSE The associations between anthropometric factors, physical activity (PA), and breast cancer risk in terms of estrogen-receptor/progesterone-receptor (ER/PgR) status have been unclear in Japanese women. This case-control study was designed to evaluate these associations. METHODS From among female patients aged 30 years and over admitted to a single hospital in Japan between 1997 and 2009, 1,017 breast cancer cases (538ER+/PgR+, 125ER+/PgR-, 23 ER-/PgR+, 249 ER-/PgR-, and 82 missing) and 2,902 controls were selected. Height, weight, body mass index (BMI) (kg/m(2)), and time spent exercising (hours/week) were assessed using a self-administered questionnaire. Polytomous logistic regression analysis and tests for heterogeneity across ER+/PgR+ and ER-/PgR- were conducted. RESULTS Higher BMI was associated with a higher risk of ER+/PgR+ cancer among women overall [odds ratio (OR) = 2.41, 95 % confidence interval (CI) 1.37-4.23 for BMI ≥30.0; P(trend) = 0.0001] and postmenopausal women (OR = 6.24, 95 % CI 2.68-14.53 for BMI ≥30.0; P trend < 0.0001). A longer time spent exercising (more than 5 h/week) showed a decreased risk for any type of breast cancer among overall and pre- and postmenopausal women, although this did not reach statistical significance. Height was not associated with any risk. CONCLUSIONS Higher BMI is associated with an increased risk of ER+/PgR+ cancer among women overall and postmenopausal women. PA might be associated with a decreased risk of any type. To prevent breast cancer, weight control and PA are important.
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Wu AH, Vigen C, Razavi P, Tseng CC, Stancyzk FZ. Alcohol and breast cancer risk among Asian-American women in Los Angeles County. Breast Cancer Res 2012. [PMID: 23185976 PMCID: PMC4053138 DOI: 10.1186/bcr3363] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Introduction The role of alcohol and breast cancer risk in Asians has not been well studied. Recent studies suggest that even moderate alcohol intake may be associated with an increase in breast cancer risk, and this may be particularly relevant as alcohol intake is traditionally low among Asians. Methods We investigated the association between lifetime alcohol intake (including frequency, quantity, duration, timing, and beverage type) and breast cancer in a population-based case-control study of 2,229 Asian Americans diagnosed with incident breast cancer and 2,002 matched control women in Los Angeles County. Additionally, we examined the relation between current alcohol intake and serum concentrations of sex-hormones and growth factors in a subset of postmenopausal control women. Results Regular lifetime alcohol intake was significantly higher in US-born than non-US-born Asian Americans (P < 0.001) and almost twice as common in Japanese- than in Chinese- and Filipino-Americans (P < 0.001). Breast cancer risk increased with increasing alcohol intake among US-born Asian Americans; the odds ratios (ORs) per 5 grams per day and per 10 years of drinking were 1.21 (95% confidence interval (CI) 1.00 to 1.45) and 1.12 (95% CI, 0.98 to 1.28), respectively. Regular alcohol intake was a significant risk factor for Japanese-, but not for Chinese- and Filipino-Americans. Current consumers compared with nondrinkers showed lower concentrations of insulin-like growth factor binding protein 3 (P = 0.03) and nonsignificantly higher concentrations of estrone and androgens. Conclusions Regular lifetime alcohol intake is a significant breast cancer risk factor in US-born Asian Americans and Japanese Americans, emphasizing the importance of this modifiable lifestyle factor in traditionally low-risk populations.
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Fredslund SO, Bonefeld-Jørgensen EC. Breast cancer in the Arctic--changes over the past decades. Int J Circumpolar Health 2012; 71:19155. [PMID: 22901290 PMCID: PMC3422501 DOI: 10.3402/ijch.v71i0.19155] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 04/13/2012] [Accepted: 06/21/2012] [Indexed: 12/19/2022] Open
Abstract
The purpose of this study is to review the current literatures on breast cancer (BC) in the Arctic, especially the trends in incidence during the last decades and the possible explanations. The design of this study is a literature review. The scientific literature concerning BC were reviewed, especially focusing on the Arctic and the special conditions that exist in this region. Breast cancer incidence is increasing all over the world, including in the Arctic. The enormous transition in health conditions and lifestyle in the Arctic might be contributing to the known risk factors. In Greenland, the age at menarche has diminished by 3 years during the course of 100 years, and the number of children per women as well as the duration of breastfeeding is decreasing. Obesity and intake of saturated fat is increasing and the intake of traditional food rich in unsaturated fat and vitamin D decreasing. Smoking and alcohol consumption in the Arctic has been relatively high but is now decreasing. More focus on genetic susceptibility in relation to BC has identified the specific BRCA1 founder mutation in the Greenlandic population, which might appear to be an important risk factor. However, the known established risk factors alone cannot account for the increasing trend observed. Studies suggest that environmental contaminants such as persistent organic pollutants (POPs) including perfluorinated compounds increase the risk of BC possibly in conjunction with certain genetic polymorphisms involved in carcinogen activation. The lipophilic POPs such as polychlorinated biphenyls and organochlorine pesticides are found at very high levels in the Arctic population. Several factors can explain the increasing incidence of BC in the Arctic. The transition in lifestyle and health conditions unfortunately increases the known risk factors of BC. Moreover, the population of the Arctic might show up to be especially vulnerable because of the contemporary high burden of POPs and genetic susceptibility.
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Affiliation(s)
- Stine Overvad Fredslund
- Department of Public Health, Centre of Arctic Health & Unit of Cellular and Molecular Toxicology, University of Aarhus, Aarhus, Denmark
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Kawai M, Kakugawa Y, Nishino Y, Hamanaka Y, Ohuchi N, Minami Y. Reproductive factors and breast cancer risk in relation to hormone receptor and menopausal status in Japanese women. Cancer Sci 2012; 103:1861-70. [PMID: 22762156 DOI: 10.1111/j.1349-7006.2012.02379.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 06/26/2012] [Accepted: 06/27/2012] [Indexed: 12/29/2022] Open
Abstract
The associations between menstrual and reproductive factors and breast cancer risk in relation to estrogen/progesterone receptor (ER/PgR) status have been unclear in Japanese women. This case-control study evaluated these associations, overall and separately, by menopausal status. A total of 1092 breast cancer cases and 3160 controls were selected from among female patients aged 30 years and over admitted to a single hospital in Miyagi Prefecture between 1997 and 2009. The receptor status distribution among the cases (missing: 8.4%) was 571 ER+/PgR+, 133 ER+/PgR-, 24 ER-/PgR+ and 271 ER-/PgR-. Menstrual and reproductive factors were assessed using a self-administered questionnaire. Polytomous logistic regression and tests for heterogeneity across ER+/PgR+ and ER-/PgR- were conducted. Later age at menarche was significantly associated with a decreased risk of both ER+/PgR+ and ER-/PgR- cancer among women overall (P(trend) = 0.0016 for ER+/PgR+; P(trend) = 0.015 for ER-/PgR-) and among postmenopausal women (P(trend) = 0.012 for ER+/PgR+; P(trend) = 0.0056 for ER-/PgR-). Nulliparity was associated with an increased risk of ER+/PgR+, but not ER-/PgR- cancer among women overall (P(heterogeneity) = 0.019) and among postmenopausal women (odds ratio for ER+/PgR+ = 2.56, 95% confidence interval = 1.61-4.07; P(heterogeneity) = 0.0095). A longer duration of breastfeeding tended to be associated with a decreased risk in all subtypes among women overall. Later age at menarche has a protective effect against both ER+/PgR+ and ER-/PgR- cancer. However, parity might impact differently on various subtypes of breast cancer. Further studies are needed to clarify the etiology of the rare ER+/PgR- and ER-/PgR+ cancer subtypes.
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Affiliation(s)
- Masaaki Kawai
- Division of Community Health, Tohoku University Graduate School of Medicine, Sendai, Japan
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Kawai M, Minami Y, Nishino Y, Fukamachi K, Ohuchi N, Kakugawa Y. Body mass index and survival after breast cancer diagnosis in Japanese women. BMC Cancer 2012; 12:149. [PMID: 22510365 PMCID: PMC3444378 DOI: 10.1186/1471-2407-12-149] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 04/03/2012] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Body mass index (BMI) may be an important factor affecting breast cancer outcome. Studies conducted mainly in Western countries have reported a relationship between higher BMI and a higher risk of all-cause death or breast cancer-specific death among women with breast cancer, but only a few studies have been reported in Japan so far. In the present prospective study, we investigated the associations between BMI and the risk of all-cause and breast cancer-specific death among breast cancer patients overall and by menopausal status and hormone receptor status. METHODS The study included 653 breast cancer patients admitted to a single hospital in Japan, between 1997 and 2005. BMI was assessed using a self-administered questionnaire. The patients were completely followed up until December, 2008. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated according to quartile points of BMI categories, respectively: <21.2, ≥21.2 to <23.3 (reference), ≥23.3 to <25.8 and ≥25.8 kg/m2. RESULTS During the follow-up period, 136 all-cause and 108 breast cancer-specific deaths were observed. After adjustment for clinical and confounding factors, higher BMI was associated with an increased risk of all-cause death (HR = 2.61; 95% CI: 1.01-6.78 for BMI ≥25.8 vs. ≥21.2 to <23.3 kg/m²) among premenopausal patients. According to hormonal receptor status, BMI ≥25.8 kg/m² was associated with breast cancer-specific death (HR = 4.95; 95% CI: 1.05-23.35) and BMI <21.2 kg/m2 was associated with all-cause (HR = 2.91; 95% CI: 1.09-7.77) and breast cancer-specific death (HR = 7.23; 95% CI: 1.57-33.34) among patients with ER + or PgR + tumors. Analysis by hormonal receptor status also showed a positive association between BMI and mortality risk among patients with ER + or PgR + tumors and with BMI ≥21.2 kg/m² (p for trend: 0.020 and 0.031 for all-cause and breast cancer-specific death, respectively). CONCLUSIONS Our results suggest that both higher BMI and lower BMI are associated with an increased risk of mortality, especially among premenopausal patients or among patients with hormonal receptor positive tumors. Breast cancer patients should be informed of the potential importance of maintaining an appropriate body weight after they have been diagnosed.
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Affiliation(s)
- Masaaki Kawai
- Division of Community Health, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan.
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Minami Y, Nishino Y, Kawai M, Kakugawa Y. Being breastfed in infancy and adult breast cancer risk among Japanese women. Cancer Causes Control 2011; 23:389-98. [PMID: 22205179 DOI: 10.1007/s10552-011-9888-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 12/16/2011] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Being breastfed in infancy has been hypothesized to influence subsequent breast cancer risk. In a hospital-based case-control study, we investigated the relationship between having been breastfed and breast cancer risk, both overall and separately among female subjects with different birth years. METHODS The study subjects included 571 cases and 2,155 controls admitted to a single hospital in Miyagi Prefecture, Japan, between 1997 and 2005. History of having been breastfed was assessed with a self-administered questionnaire. Odds ratios (ORs) and 95% confidence interval (CI) were estimated using logistic regression. RESULTS After adjustment for known risk factors, no association for having been breastfed was observed overall (OR = 1.20; 95% CI: 0.82-1.76). Analysis stratified according to birth year (<1950, ≥1950) demonstrated heterogeneity in the association for having been breastfed between the two birth-year groups (p for interaction = 0.0006); having been breastfed was significantly associated with a decreased risk among subjects who were born before 1950 (OR = 0.59; 95% CI: 0.35-0.99), whereas no such risk reduction was observed for subjects born after 1950 (OR = 1.60; 95% CI: 0.88-2.90). CONCLUSION Although having been breastfed is not related to overall risk, birth year may modify the association between having been breastfed in infancy and breast cancer risk. In Japan, sociodemographic changes have occurred since the end of World War II. The use of standard formula supplement began to spread around 1950. The difference of breast cancer risk between birth-year groups may be attributable to these environmental changes.
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Affiliation(s)
- Yuko Minami
- Division of Community Health, Tohoku University Graduate School of Medicine, Sendai, Miyagi 980-8575, Japan.
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