Timing of menarche and first full-term birth in relation to breast cancer risk

Ages at menarche and first birth are established risk factors for breast cancer. The interval between these ages may also affect risk, since the breast is more susceptible to carcinogenic insults during this period than during the parous period. However, few investigators have studied this relation. Using logistic regression, the authors evaluated associations between the timing of reproductive events and breast cancer risk among 4,013 cases and 4,069 controls enrolled in a multicenter, population-based US case-control study of White and African-American women (1994-1998). For White, parous premenopausal and postmenopausal women, those who had an interval of > or =16 years between the ages of menarche and first birth had 1.5-fold (95% confidence interval (CI): 1.0, 2.2) and 1.4-fold (95% CI: 1.1, 1.8) increased risks of breast cancer, respectively, in comparison with those who had < or =5 years between these ages. Adjusting for age at first birth altered these risk estimates somewhat, to odds ratios of 1.5 (95% CI: 0.8, 2.9) and 1.0 (95% CI: 0.6, 1.5), respectively. These associations were stronger for lobular and hormone-receptor-positive tumors but were absent among premenopausal African-American women. The authors conclude that the interval between age at menarche and age at first birth is associated with the risk of hormonally sensitive types of breast cancer, particularly among White women.     

Associations of aging and birth cohort with body mass index in a biethnic cohort

OBJECTIVE: To examine associations of aging and birth cohort with body mass index (BMI) in a biethnic cohort. RESEARCH METHODS AND PROCEDURES: This was a longitudinal closed cohort study of 14,500 white and African-American men and women, 45 to 64 years of age, followed for 9 years. Aging was defined as the length of the interval in years between baseline and following visits. Birth cohort was defined by the year in which participants were born. Mixed model analyses were used to examine associations of aging, birth cohort, and BMI in four ethnicity-gender groups. RESULTS: We found that aging was associated with an increase in BMI in white and African-American men and women. The associations between aging and BMI were stronger in the younger birth cohorts. Except for white women, younger birth cohort was associated with a higher BMI. After adjusting for aging, birth cohort was associated with an increase in BMI of 0.1 kg/m(2) [95% confidence interval (95% CI): -0.1, 0.3] among white women. The corresponding values for African-American women, white men, and African-American men are 0.5 kg/m(2) (95% CI: 0.1, 0.9), 0.6 kg/m(2) (95% CI: 0.4, 0.8), and 0.6 kg/m(2) (95% CI: 0.2, 1.0), respectively. DISCUSSION: Our analyses show that, in all except white women, people in this age range who were born later have a higher BMI at the same attained age. In all groups, people who are born later gained more weight as they aged. In general, subjects ages 45 to 64 years gained weight as they aged 9 years.     

Associations of weight loss and changes in fat distribution with the remission of hypertension in a bi-ethnic cohort: the Atherosclerosis Risk in Communities Study

BACKGROUND: To examine associations of weight loss and changes in fat distribution with changes in blood pressure and the remission of hypertension in a community-based sample. METHODS: Participants were 3245 white and African-American men and women, 45-64 years of age, who participated in the Atherosclerosis Risk in Communities Study over an average of 9 years. Mixed models analyses were used to examine the associations of weight loss and changes in fat distribution with changes in blood pressure. Proportional hazard models with time-dependent covariates were used to examine the associations of weight loss and changes in fat distribution with the remission of hypertension. RESULTS: Weight loss was associated with a decrease in systolic blood pressure and diastolic blood pressure and with an increased rate of remission of hypertension. Hazard ratios of the remission of hypertension associated with 1-kg increment in annual weight loss were 2.04 (95% confidence interval [CI]: 1.62-2.59), 1.38 (95% CI: 1.14-1.67), 1.84 (95% CI: 1.47-2.29), and 1.53 (95% CI: 1.14-2.05) for white women, African-American women, white men, and African-American men, respectively. Changes in fat distribution were associated with the remission of hypertension in younger (45-54 years) participants. CONCLUSIONS: Weight loss was associated with a decrease in blood pressure and with remission of hypertension in white and African-American men and women.     

Hysterectomy prevalence by Hispanic ethnicity: evidence from a national survey

OBJECTIVES: We investigated hysterectomy prevalence among Hispanic women. METHODS: We obtained data from 4684 Hispanic women and 20 604 non-Hispanic White women from the 1998-1999 National Health Interview Survey. We calculated nationally representative odds ratios of previous hysterectomy, controlling for confounders. RESULTS: Compared with non-Hispanic White women, the odds ratio for hysterectomy was 0.36 (95% confidence interval [CI] = 0.30, 0.44) for Hispanic women with no high school diploma, 0.57 (95% CI = 0.44, 0.74) for high school graduates, and 0.67 (95% CI = 0.42, 0.87) for college attenders. Country of origin had little influence on hysterectomy prevalence. Hysterectomy was positively associated with acculturation. CONCLUSIONS: Hispanic women undergo fewer hysterectomies than do non-Hispanic White women. The reasons for this, as well as information on ethnicity-specific appropriateness of hysterectomy, should be explored.     

Body size and breast cancer risk in black women and white women: the Carolina Breast Cancer Study

The relation between body size and breast cancer risk was investigated in a population-based, case-control study of Black women (350 cases, 353 controls) and White women (523 cases, 471 controls) from North Carolina, aged 20-74 years in 1993-1996. Logistic regression analyses compared tertiles of each body size variable, adjusting for age and breast cancer risk factors (results shown for highest relative to lowest tertile). Among premenopausal women, body mass index (kg/m2) was inversely associated with breast cancer (odds ratio (OR) = 0.46, 95% confidence interval (CI): 0.26, 0.80) for Whites but not for Blacks. There was essentially no association among postmenopausal women. Higher waist/hip ratio, adjusted for body mass index, increased risk for all women. Odds ratios for Black and White premenopausal women were 2.50 (95% CI: 1.10, 5.67) and 2.44 (95% CI: 1.17, 5.09), respectively; odds ratios for Black and White postmenopausal women were 1.62 (95% CI: 0.70, 3.79) and 1.64 (95% CI: 0.88, 3.07), respectively. Findings for body mass index differed among Black women when stratified by age (<50 years) (OR = 0.50, 95% CI: 0.25, 1.01) instead of menopausal status. Thus, the associations of breast cancer with body mass index and waist/hip ratio among Black women are similar to those documented for Whites, despite different body size profiles on average.     

Birth characteristics and leukemia in young children

The relation between birth characteristics and leukemia in young children was investigated in a large population-based study in California. Cases were obtained from the statewide cancer registry for 1988-1997. During this time, 1,957 leukemia cases were diagnosed among children under age 5 years. Of these, 1,728 (88%) were matched to a California birth certificate. Two control birth certificates, matched on date of birth and sex, were randomly selected from the statewide birth registry for each case. Analyses were performed separately for acute lymphoid leukemia (ALL) and acute nonlymphoid leukemia (ANLL). Odds ratios and 95% confidence intervals were estimated from conditional logistic regression. The strongest finding was for greatly increased risk of both types of leukemia in children with Down's syndrome (22 cases and no controls). African-American children had strikingly decreased risk for ALL (odds ratio (OR) = 0.29, 95% confidence interval (CI): 0.20, 0.42), and Asian/Pacific Islanders had increased risk for ANLL (OR = 2.00, 95% CI: 1.19, 3.36). Older maternal age was associated with slightly increased risk for ALL (maternal age > or =35 years, OR = 1.25, 95% CI: 1.04, 1.52), although this odds ratio was somewhat reduced when adjusted for other factors. No strong relations were observed for birth weight and ALL or ANLL.     

Cigarette smoking and risk of breast carcinoma in situ

BACKGROUND: Although the associations with cigarette smoking have been explored extensively for invasive breast cancer, the relation to in situ cancer has not previously been examined in depth. METHODS: We analyzed data from a population-based case-control study of women living in Wisconsin, Massachusetts, and New Hampshire. Eligible cases of incident breast carcinoma in situ were reported to statewide registries in 1997-2001 (n = 1878); similarly aged controls (n = 8041) were randomly selected from population lists. Smoking history and other risk factor information were collected through structured telephone interviews. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated from logistic regression models adjusting for potential confounders. RESULTS: In multivariate models, the OR for breast carcinoma in situ among current smokers was 0.8, compared with never-smokers (95% CI = 0.7-1.0). Risk estimates increased towards the null with greater time since smoking cessation. Odds ratios were also less than 1.0 among women who initiated smoking in adolescence (OR = 0.8) or after a full-term birth (OR = 0.7), relative to women who never smoked. The reduced odds ratios associated with current smoking were strongest among women with annual screening mammograms (OR = 0.7; 95% CI = 0.6-0.9). Odds ratios were not less than 1.0 among current smokers without a recent screening mammogram (1.3; 0.9-2.0). CONCLUSIONS: Our findings suggest an inverse association between current smoking and risk of breast carcinoma in situ among women undergoing breast cancer screening.     

Maternal age, exposure to siblings, and risk of amyotrophic lateral sclerosis

Between 1987 and 2005, the authors conducted a nested case-control study based on the Swedish Multi-Generation Register to investigate whether early life exposures, namely, maternal age at delivery and exposure to siblings, are associated with an increased risk of amyotrophic lateral sclerosis (ALS). The study comprised 768 ALS cases and five controls per case matched by birth year and gender. Odds ratios and their corresponding 95% confidence intervals for ALS were estimated by conditional logistic regression modeling. Low maternal age (< or =20 years) and high maternal age (> or =41 years) were both associated with higher risk of ALS (odds ratio (OR) = 1.5, 95% confidence interval (CI): 1.1, 2.0 and OR = 1.7, 95% CI: 1.1, 2.4, respectively). The relative risk of ALS increased slightly with increasing number of younger siblings (OR = 1.1, 95% CI: 1.0, 1.1; p = 0.02). Children whose first younger sibling was born after the age of 6 years had the greatest relative risk (OR = 1.8, 95% CI: 1.2, 2.7). Exposure to older siblings was not associated with the risk of ALS. Although the strength of the observed associations was modest, these results provided further support for the theory that early life exposures might contribute to the disease pathogenesis.     

Differential distribution of allelic variants in cytokine genes among African Americans and White Americans

Racial disparities in health are largely unexplained. Because many diseases causing premature mortality among African Americans are mediated by the immune system, the authors explored the race-specific distribution of allelic variants in cytokine genes known to stimulate inflammation. The authors studied women seeking prenatal care and delivering singletons in uncomplicated first births at a US hospital in 1997-2001. A total of 179 African-American women and 396 White women were evaluated for functionally relevant allelic variants in cytokine genes. African-American women were significantly more likely to carry allelic variants known to up-regulate proinflammatory cytokines; odds ratios increased with allele dose. Odds ratios for African Americans versus Whites in genotypes up-regulating proinflammatory interleukin (IL) 1 (IL1A-4845G/G, IL1A-889T/T, IL1B-3957C/C, and IL1B-511A/A) ranged from 2.1 to 4.9. The proinflammatory cytokine interleukin-6 IL6-174 G/G genotype was 36.5 times (95% confidence interval (CI): 8.8, 151.9) more common among African Americans. Genotypes known to down-regulate the antiinflammatory interleukin-10 (IL10-819 T/T and IL10-1082 A/A) were elevated 3.5-fold (95% CI: 1.8, 6.6) and 2.8-fold (95% CI: 1.6, 4.9) in African Americans. Cytokine genotypes found to be more common in African-American women were consistently those that up-regulate inflammation.     

Comparative analysis of breast cancer risk factors among African-American women and White women

The authors assessed risk factor profiles among 1,505 African-American and 1,809 White women in the 1993-2001 Carolina Breast Cancer Study. Multiple logistic regression models for case-control data were used to estimate odds ratios for several factors. Racial differences were observed in the prevalence of many breast cancer risk factors among both younger (aged 20-49 years) and older (aged 50-74 years) women. For older women, the magnitude and direction of associations were generally similar for African-American and White women, but important racial differences were observed among younger women. In particular, multiparity was associated with increased risk of breast cancer among younger African-American women (for three or four pregnancies: adjusted odds ratio (OR) = 1.5, 95% confidence interval (CI): 0.9, 2.6; for five or more pregnancies: OR = 1.4, 95% CI: 0.6, 3.1) but not among younger White women (for three or four pregnancies: OR = 0.7, 95% CI: 0.4, 1.2; for five or more pregnancies: OR = 0.8, 95% CI: 0.2, 3.0). The relations with age at first full-term pregnancy and nulliparity also varied by race. Case-only analyses before and after further adjustment for tumor stage and hormone receptor status revealed little effect on results. Hence, racial variations in both prevalences of and risks associated with particular factors may contribute to the higher incidence of breast cancer among younger African-American women.     

Regional pattern of hysterectomy among women in India: Evidence from a recent large scale survey

ABSTRACT

Hysterectomy is one of the major public health issues today. In India, women’s attitudes toward menstruation may be a significant driver in seeking hysterectomy. Therefore, we attempted to study the prevalence, associated factors and reasons for hysterectomy among 540,671 ever-married women aged 15–49 years, using data from the National Family Health Survey (NFHS-4) conducted during 2015–16 in India. Univariate, bivariate and multivariate analyses were conducted. These analyses revealed that the prevalence of hysterectomy was 4.1%. The prevalence was highest in the southern region and lowest in the north-eastern regions of India. Results of multivariate models indicated that high parity (odds ratio [OR] 2.84; 95% confidence interval [CI] 2.52–3.19), high body mass index (OR-1.43; 95% CI 1.35–1.51), older age, early age at first cohabitation, and illiteracy were positively associated with hysterectomy. Excessive menstrual bleeding was the leading reason for hysterectomy in this sample. Hysterectomy has exhibited an upward trend over the years. This may exert adverse effects on the physical, socio-psychological and reproductive health of women. Therefore, it is essential to promote high-quality prevention and treatment choices for women, rather than permanent but potentially inappropriate solutions such as hysterectomy.     

Risk of myocardial infarction after oophorectomy and hysterectomy

To determine the risk of developing a first myocardial infarction after a hysterectomy and/or oophorectomy. Case-cohort analysis performed among 17,126 women in the Uppsala Health Care Region of Sweden, who had undergone a hysterectomy and/or oophorectomy in 1965 to 1983. Record linkage was used for follow-up and medical records to ascertain the actual history of oophorectomy. Risk estimates were calculated by relating the observed number of cases in the cohort to that expected on the basis of incidence rates in the population. Overall, 214 cases of myocardial infarction were observed. In premenopausal women a bilateral oophorectomy alone tended to increase the relative risk 1.6; 95% CI 0.8-3.1, but this operation combined with hysterectomy increased the risk only among those aged 50 and over at surgery. Hysterectomy at premenopausal age or unilateral oophorectomy did not alter the risk of myocardial infarction. In naturally menopausal women, hysterectomy-mainly for uterine myoma-was associated with a four-fold increase in relative risk (3.8; 95% CI 1.9-7.8). Hysterectomy for treatment of myoma performed after a natural menopause is linked to an excess risk for myocardial infarction. Bilateral oophorectomy before menopause may increase the risk of myocardial infarction.     

Hysterectomy, tubal sterilization, and the risk of breast cancer

Studies suggest that hysterectomy and tubal sterilization may alter the function of the remaining ovaries. Conceivably, this effect could alter breast cancer risk. To investigate whether these surgeries affect breast cancer risk, the authors analyzed data collected between December 1, 1980, and April 30, 1983, in a population-based, case-control study of women aged 20-54 years, the Cancer and Steroid Hormone Study. Compared with never-sterilized women, women with hysterectomy and no remaining ovaries had a decreased risk of breast cancer (relative risk (RR) = 0.7, 95% confidence interval (CI) = 0.6-0.8). Risk was lowest in women who had their surgery before age 40 years or 15 or more years in the past; surgery at an early age provided greater protection than surgery in the distant past. Hysterectomy with one or two remaining ovaries was also inversely associated with breast cancer risk (RR = 0.8, 95% CI = 0.7-0.9), but no relation was found with age at surgery or time since surgery. Women with tubal sterilization had a slightly increased risk of breast cancer, which was of borderline statistical significance (RR = 1.2, 95% CI = 1.0-1.3). However, no relation was found with age at surgery or time since surgery. The data suggest that hysterectomy with bilateral oophorectomy decreases the breast cancer risk in women aged less than 55 years, possibly by curtailing ovarian function at a critical period. However, neither hysterectomy without bilateral oophorectomy nor tubal sterilization appears to substantially alter breast cancer risk in women of this age.     

Reproductive factors and risk of myocardial infarction.

The relation of reproductive factors to risk of myocardial infarction in women aged 45-69 years was examined in a case-control interview study carried out in Massachusetts from 1986 to 1990. Each of 858 cases of first myocardial infarction was age-matched with a control from the same precinct of residence. Conditional logistic regression was used to control the matching factors and the major known and suspected risk factors for coronary heart disease. For parous women compared with nulliparous women, the estimated relative risk of myocardial infarction was 1.8 (95% confidence interval (CI) 1.0-3.3). Among parous women, the relative risk estimate for five or more births relative to fewer births was 1.4 (95% CI 1.0-2.0); the estimate for a first birth before age 20 relative to a later age at first birth was 1.7 (95% CI 1.1-2.6). The greatest increase in risk was observed for women who had both an early age at first birth and five or more children. However, confounding by factors related to socioeconomic status may have contributed to the results. Compared with women who had a natural menopause at age 50 or older, women who reached the menopause before age 45 were at increased risk regardless of type of menopause: The estimated relative risks were 2.1 (95% CI 1.3-3.2), 1.7 (95% CI 1.0-2.7), and 1.7 (95% CI 1.0-2.8) for early natural menopause, bilateral oophorectomy, and hysterectomy with retention of one or both ovaries, respectively. These results suggest that early cessation of ovulatory function, whether due to natural causes or to surgery, increases the risk of myocardial infarction. Age at menarche was not related to myocardial infarction risk.     

Breast cancer risk and ovariectomy, hysterectomy, and tubal sterilization in the women's contraceptive and reproductive experiences study

Removal or impairment of ovaries before menopause may affect a woman's breast cancer risk by altering her cumulative exposure to ovarian hormones. The Women's Contraceptive and Reproductive Experiences Study, a population-based, multicenter case-control study of incident invasive breast cancer, recruited women aged 35-64 years (4,490 cases and 4,611 controls) who provided data on ovariectomy, hysterectomy, and tubal sterilization during in-person interviews. Controls were frequency-matched to cases by age, race, and study site. Unconditional logistic regression analysis was used. Women who had not undergone premenopausal reproductive surgery were the referent group. Bilateral ovariectomy was associated with reduced breast cancer risk overall (odds ratio (OR) = 0.59, 95% confidence interval (CI): 0.50, 0.69) and among women <45 years of age (ORs ranged from 0.31 to 0.52), but not among those who were older at surgery. It was also associated with a reduced risk for estrogen and progesterone receptor-positive tumors (OR = 0.63, 95% CI: 0.52, 0.75) but not receptor-negative tumors. Hysterectomy with ovarian conservation (OR = 0.83, 95% CI: 0.72, 0.96) and hysterectomy with partial ovary removal (OR = 0.73, 95% CI: 0.59, 0.91) were also associated with lower risk. No association with breast cancer risk was observed with tubal sterilization only or partial ovariectomy without hysterectomy. Reproductive organ surgeries may alter ovarian hormone levels, thereby affecting breast cancer risk.     

Reproductive history and mortality in late middle age among Norwegian men and women

There is growing recognition that reproductive patterns may have long-term health implications, although most evidence is restricted to women. The authors used register data to derive fertility histories for all Norwegian men and women born in 1935-1958. Discrete-time hazard modeling was used to analyze later-life mortality by aspects of reproductive history. A total of 63,312 deaths were observed during 14.5 million person-years of follow-up in 1980-2003, when subjects were aged 45-68 years. Models included detailed information on educational qualifications and marital status. Odds of death relative to those for subjects with two children were highest for the childless (women: odds ratio (OR) = 1.50, 95% confidence interval (CI): 1.43, 1.57; men: OR = 1.35, 95% CI: 1.30, 1.40) and next highest for those with only one child (women: OR = 1.31, 95% CI: 1.26, 1.37; men: OR = 1.20, 95% CI: 1.16, 1.24). Results for the parous showed a positive association between earlier parenthood and later mortality, a reverse association with late age at last birth, and an overall negative association between higher parity and mortality. The similarity of results for women and men suggests biosocial pathways underlying associations between reproductive history and health. The lack of any high-parity disadvantage suggests that in the "family friendly" Norwegian environment, the health benefits of having several children may outweigh the costs.     

Obesity and associated coronary heart disease risk factors in a population of low-income African-American and white women: the North Carolina WISEWOMAN project

BACKGROUND: Obesity has been associated with many co-occurring coronary heart disease (CHD) risk factors as well as CHD mortality. These associations have been shown to vary between African-American and white sample populations. METHODS: The authors examined whether obesity co-occurs with several CHD risk factors (diabetes, hypertension, hypercholesterolemia, low high-density lipoprotein cholesterol (HDL-C)), and estimated the 10-year risk for CHD in the North Carolina WISEWOMAN (Well Integrated Screening and Evaluation for Women Across the Nation) study sample. This sample includes low-income African-American and white women (> or = 50 years of age). RESULTS: Among white women (n = 1,284), 34% were overweight (BMI = 25.0-29.99 kg/m(2)) and 35% obese (BMI > or = 30 kg/m(2)); among African-American women (n = 754), 28% were overweight and 59% obese. Among obese and nonobese African-American women, the prevalence of three or more co-occurring risk factors was similar (obese = 17.7% (95% confidence interval (CI): 13.9, 21.6) and nonobese = 13.3% (95% CI: 8.7, 17.8)). By contrast, the prevalence among white women was greater among the obese (26.9% (95% CI: 22.9, 31.0)) than the nonobese (13.0% (95% CI: 9.7, 16.2)). CONCLUSIONS: The differences between and within African-American and white women may be accounted for by the high levels of HDL-C among obese and nonobese African-American women.     

Correlates of Intent to Seek Unnecessary Pap Tests Among Elderly Women

PURPOSE: Cervical cancer screening may be over-used by elderly women who might not benefit from the test. The purpose of this study was to examine the relative importance of objective factors (e.g. intact cervix) and subjective factors (e.g. patients' Pap-smear related beliefs/attitudes) as correlates of elderly women's intention to have a Pap smear. METHODS: This study was a secondary data analysis using a subset sample of the elderly women (>or=65 years) who participated in the Texas Tech 5000 Survey Wave 4, a cross-sectional phone interview study conducted in 2002. Intent to have a Pap test, previous gynecologic history, and beliefs/attitudes related to Pap tests were measured. chi2 tests and logistic regression were conducted. RESULTS: Among the 1,044 women in the analytical sample, 70.2% (733) reported intending to have a Pap smear test within the next 2 years. About 77% (449/582) of the women who had not undergone a hysterectomy reported the intend to have a Pap smear, whereas 62% (284/462) of the women who had undergone a hysterectomy reported the same intent (chi 2 = 30.26; df = 1; p = .000). Among women who had undergone a hysterectomy, having received a Pap smear within the past 2 years (odds ratio OR, 21.32; 95% confidence interval [CI], 11.52-39.47), perceiving that their doctors might feel having the test is a good idea (OR, 7.14; 95% CI, 3.15-16.19), and insurance covering the test (OR, 2.21; 95% CI, 1.18-4.15) were positive correlates of intent to have a Pap test. Among women who had not undergone a hysterectomy, previous Pap smear history (OR, 19.28; 95% CI, 10.15-37.10), perceived doctor's opinion (OR, 5.39; 95% CI, 2.38-12.19), perceived pain of the test (OR, 0.52; 95% CI, .28-.99), perceived importance (OR, 4.00; 95% CI, 1.32-12.10), and perceived risk of developing cervical cancer (OR, 4.27; 95% CI, 1.27-14.33) were correlates. CONCLUSIONS: Public health educational messages intended to increase appropriate use of Pap screening should include factual information about risk factors such as age and possession of an intact cervix. Other messages intended to reduce inappropriate use of Pap screening should be directed at physicians, since many elderly women intend to inappropriately seek Pap tests based on erroneous beliefs/attitudes.     

Risk factors for uterine fibroids among women undergoing tubal sterilization

Uterine leiomyomas are reported to be the most common benign gynecologic tumors affecting premenopausal women, and they are often associated with considerable morbidity. The purpose of this study was to identify risk factors for uterine fibroids among women undergoing tubal sterilization. Cases comprised women aged 17-44 years whose uterine fibroids were first visualized at the time of tubal sterilization (1978-1979 or 1985-1987) or who reported a history of uterine fibroids (n = 317). Controls were randomly selected from women with no laparoscopic evidence of or history of fibroids (n = 1,268). Adjusted odds ratios were estimated using unconditional logistic regression separately for White (n = 1,235) and African-American (n = 350) women. Risk factors for White women included: age 40-44 years (odds ratio (OR) = 6.3; 95% confidence interval (CI): 3.5, 11.6), > or =5 years since last delivery (OR = 1.9; 95% CI: 1.1, 3.1), lifetime cigarette smoking of > or =1 pack/day (OR = 1.6; 95% CI: 1.1, 2.3), menstrual cycle length of >30 days (OR = 1.6; 95% CI: 1.1, 3.3), and menstrual bleeding for > or =6 days (OR = 1.4; 95% CI: 1.0, 2.0). Parous women were at reduced risk compared with nulliparous women (OR = 0.2; 95% CI: 0.1, 0.3). Advancing age was the only significant risk factor for African-American women (ages 40-44 years, OR = 27.5; 95% CI: 5.6, 83.6). Current oral contraceptive use and elective abortion were not associated with fibroids.     

Influence of diabetes mellitus type 2 and prolonged estrogen exposure on risk of breast cancer among women in Armenia

Diabetes mellitus type 2 (DM2) and breast cancer (BrCa) are prevalent in Armenia. We investigated DM2, reproductive factors, and BrCa in a case control study of 302 women. Multiple logistic regression analyses revealed DM2 increased adjusted odds of BrCa by 5.53 (95% CI 1.34-22.81). Any birth was protective (adjusted OR=0.36, 95% CI 0.20-0.66). Each year delay in first pregnancy increased risk (adjusted OR=1.13, 95% CI 1.01-1.27) as did induced abortions (adjusted OR=2.86, 95% CI 1.02-8.04). Odds ratios were adjusted for age and body mass index (BMI), which confounded associations between DM2 and BrCa. We suggest our findings imply the need for further investigation in Armenian and in other populations with similar characteristics.