Reproductive factors and breast cancer in New Zealand.
ABSTRACT A national population-based case-control study was used to assess the influence on breast cancer risk of reproductive factors and the possibility of an interaction with age at diagnosis. A total of 891 women aged 25 to 54 with a first diagnosis of breast cancer, and 1864 control subjects, randomly selected from the electoral rolls, were interviewed. There was a declining risk of breast cancer with increasing age at menarche (p = 0.06), the strongest effect being seen in women aged less than 40. Parous women had a 27% lower risk of breast cancer than nulliparous women, a reduced risk being evident in all but the youngest age group. A falling risk of breast cancer with rising parity was clear only in women diagnosed when aged at least 45 years. Breast cancer risk tended to fall amongst parous women with increasing duration of breastfeeding (p = 0.14); the association was most apparent in the youngest women, while those over 40 years at diagnosis showed no clear negative trend. There was no association of breast cancer risk with age at first full-term pregnancy, time since last full-term pregnancy, abortion (spontaneous or induced), abortion before first full-term pregnancy, or ability to conceive, and there was no trend in risk with age at natural menopause. Women in the highest category of body mass index at age 20 had the lowest risk of breast cancer in the age group studied. When each reproductive factor was formally tested for effect modification by age at diagnosis, the interaction term in logistic models approached statistical significance only for parity (p = 0.07).
SourceAvailable from: Hebestreit AntjeBreast Cancer Research and Treatment 01/2013; Breast Cancer Res Treat(142):133-141. DOI:10.1007/s.10549-010-1255-7 · 4.20 Impact Factor
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ABSTRACT: To evaluate at what age parous and nonparous women were diagnosed with breast cancer. Factors taken into account for parous women were whether they had breastfed their children, and if so, the length of the lactation period. Other factors considered for both groups were obesity, family histories of cancer, smoking habits and alcohol consumption. Breast cancer is the most common form of cancer in younger women in Western countries. Its growing incidence as well as the increasingly early age of diagnosis led us to carefully analyse its possible causes and the preventive measures to be taken. This is a particularly important goal in epidemiological research. A retrospective study of the clinical histories of patients diagnosed with breast cancer at the San Cecilio University Hospital in Granada (Spain). In this study, we analysed 504 medical records of female patients, 19-91 years of age, who had been diagnosed and treated for breast cancer from 2004-2009 at the San Cecilio University Hospital in Granada (Spain). Relevant data (age of diagnosis, period of lactation, family history of cancer, obesity, alcohol consumption and smoking habits) were collected from the clinical histories of each patient and analysed. A conditional inference tree was used to relate the age of diagnosis to smoking habits and the length of the lactation period. The conditional inference tree identified significant differences between the age of the patients at breast cancer diagnosis, smoking habits (p < 0·001) and lactation period if the subjects had breastfed their children for more than six months (p = 0·006), regardless of whether they had a family history of cancer. Our study concluded that breastfeeding for over six months not only provides children with numerous health benefits, but also protects mothers from breast cancer when the mothers are nonsmokers. Nurses play a crucial role in encouraging new mothers to breastfeed their children, and this helps to prevent breast cancer.Journal of Clinical Nursing 08/2013; 23(17-18). DOI:10.1111/jocn.12368 · 1.23 Impact Factor
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ABSTRACT: Introduction: Breast cancer is the most common gynecological tumor in young women in Western countries. Its profound implications for health and an increasingly early age of diagnosis have been carefully analyzed its causes and possible preventive measures, making their study in a primary goal of epidemiological research. Sample and methods: We reviewed medical records pertaining to 504 female patients aged 19 to 91 years. All of them were diagnosed and treated for breast cancer between 2003-2008 at the Hospital Universitario "San Cecilio" of Granada (Spain). Results: We found a significant correlation (p = 0.001) between the age of cancer diagnosis, length of breastfeeding, and the existence of personal and family history for cancer. By contrast, there were no statistically significant differences test (t-test) between the average age of diagnosis of cancer and having had offspring or not (t = 0.559, p = 0.576). Conclusions: Breastfeeding for periods of longer than six months, not only provides children with many health benefits, but may also protect the mother from serious diseases, such as breast cancer.Nutricion hospitalaria: organo oficial de la Sociedad Espanola de Nutricion Parenteral y Enteral 12/2010; 25(6):954-958. · 1.25 Impact Factor