Publications

Publications from the current and previous year are listed below; articles are listed chronologically within each year from the most to the least recent.

Most research articles have brief description below and a link to the published abstract (a detailed summary) through the US. National Library of Medicine.

For prior years, click on the following links:

20142013201220112010

2009200820072006200520042003200220012000

199919981995-1997

BWHS_Printer friendly publication list, October 2016 (articles listed from most to least recent)

Last Updated: October 20, 2016

2016

Evidence from studies of white women has suggested that physical activity may reduce the risk of developing breast cancer. In a previous study in the BWHS, vigorous exercise was associated with lower risk of breast cancer. In the present analysis based on data in the African American Breast Cancer Epidemiology and Risk Consortium of four large studies of African American women, in which the BWHS is participating, recent vigorous exercise was associated with reduced risk of estrogen receptor positive breast cancer.  link to online article

Vitamin D deficiency, which has been linked to an increased risk of colorectal cancer, is common among African Americans. Studies of vitamin D deficiency and breast cancer risk, conducted mostly in white women, have been conflicting. To study the relation of vitamin D levels to breast cancer risk in the BWHS, we first developed a vitamin D prediction model.  The model was based on comparing measured levels of vitamin D (specifically, 25-hydroxyvitamin D) in blood samples provided by BWHS participants with levels predicted by models based on participants’ vitamin D consumption in the diet and from supplements, weight, cigarette smoking, and several other factors. The model was then used to predict vitamin D levels among all women in the BWHS. Using the predicted levels of vitamin D together with information on breast cancer occurrences, we estimated that women with the lowest levels of vitamin D had an increased risk of breast cancer compared with women with higher levels. These results suggest that treating vitamin D deficiency could result in lower risk of breast cancer.  link to online article

A signaling pathway in the body, called HIPPO, regulates cell growth and survival. Based on genotyping data in the African American Breast Cancer Epidemiology and Risk Consortium of studies of African American women, in which the BWHS is participating, we found that the several genetic variants in the Hippo signaling pathway were significantly associated with estrogen-receptor negative and estrogen receptor positive breast cancer.  link to online article

Coffee consumption has been reported to be inversely associated with hepatocellular carcinoma (HCC), the most common type of liver cancer. There have been no studies of coffee and intrahepatic cholangiocarcinoma (ICC), the second most common type of liver cancer. In the Liver Cancer Pooling Project, a consortium of U.S.-based cohort studies, including the BWHS, data from 1,212,893 individuals, including 860 with HCC and 260 with ICC, were assessed. Consumption of more than 3 cups of coffee per day, relative to nondrinking, was associated with a 27% lower risk of HCC. The risk reduction was greater in women than in men. The associations were stronger for caffeinated coffee than decaffeinated coffee. There was no association between coffee consumption and ICC. These findings suggest that coffee consumption in the U.S. is associated with reduced risk of HCC.  link to online article

Experimental studies have suggested that nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin and ibuprofen, may potentially protect against liver cancer. As part of the Liver Cancer Pooling Project, we assessed data on 1,084,133 individuals (including 679 with hepatocellular carcinoma (HCC) and 225 with intrahepatic cholangiocarcinoma (ICC) from 10 U.S.-based cohort studies, including BWHS. Current aspirin use, versus nonuse, was with a 32% lower risk of HCC; the association was stronger for users who reported daily use, longer duration use, and lower dosage. Ibuprofen use was not associated with HCC risk. Aspirin use was associated with a reduced ICC risk in men but not women.  link to online article

Hepatocellular carcinoma (HCC) occurs less commonly among women than men in almost all regions of the world. The disparity in risk is particularly notable prior to menopause suggesting that hormonal exposures during reproductive life may be protective. In the Liver Cancer Pooling Project, a consortium of US-based cohort studies, data from 799,500 women in 11 cohorts, including BWHS, were assessed. Bilateral oophorectomy (removal of both ovaries) was associated with a significantly increased risk of HCC. There was no association of oral contraceptives use, parity, age at first birth, age at natural menopause, or duration of fertility with HCC. These findings do not help to explain the female/male disparity in HCC incidence.  link to online article

Evidence has been growing that sedentary behavior, such as long hours of sitting, increases the risk of several illnesses, independent of physical activity.  We evaluated whether time spent sitting at work or time spent watching television, or both combined, was associated with breast cancer risk in the BWHS.  We found that higher levels of total time sitting reported at baseline in 1995, as well as updated total time sitting based on data provided during follow-up, were associated with increased incidence of breast cancer. These association were present among women who exercised on a regular basis as well as among those who did not exercise.  In a previous BWHS study, vigorous exercise was associated with reduced risk of breast cancer.  Thus, BWHS findings suggest that high sedentary time may increase risk for breast cancer among Black women, while vigorous exercise may lower risk.  link to online article

In women of European ancestry, an association of a particular gene near the fatty acid synthase (FASN) gene has been found to occur more commonly among women with uterine fibroids. We assessed that possibility in the BWHS. We found no association with risk of fibroids overall. On average, African American women have about 20% European ancestry; we found that among women with higher European ancestry (40% or more), the genetic variant in question was associated with increased risk of fibroids.  link to online article

The influence of genetic background on risk of breast cancer has been studied mainly among European and Asian women. We conducted an analysis of rare genetic variants in relation to risk of breast cancer breast cancer in the African American Breast Cancer Epidemiology and Risk Consortium, which includes data from four large studies of African American women, including the BWHS. There were no significant associations with overall risk of breast cancer, but a gene not previously identified and a gene previously identified in women of European ancestry were significantly associated with risk of estrogen-receptor negative breast cancer and triple negative breast cancer.  link to online article

Genome-wide association studies (GWAS) of lung cancer have identified regions of genetic variants associated with lung cancer risk in Europeans and Asians. The present study was a GWAS in African Americans, who have higher rates of lung cancer despite smoking fewer cigarettes per day when compared with other population groups. We confirmed results previously reported in African Americans and other populations for two loci near plausible candidate genes that are associated with lung cancer. Additional work is required to map and understand the biological underpinnings of the strong association of these loci with lung cancer risk in African Americans.  link to online article

We evaluated whether adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations was associated with colorectal cancer incidence in the BWHS. The seven recommendations involved healthy weight, exercise, and dietary intake.  Adherence to cancer prevention recommendations was low and not associated with colorectal cancer risk. The validity of existing recommendations in diverse populations needs further study, as well as whether there are alternative recommendations that are more beneficial for cancer prevention in specific populations.  link to online article

Multiple myeloma (MM) is a relatively rare cancer that occurs more commonly among African Americans than among other population groups. Obesity also occurs more commonly among African Americans as well but its relation to multiple myeloma is undetermined. We combined data from seven cohort studies, including the BWHS, that tracked mortality among Africans Americans.  MM mortality increased as body mass index increased and was 43% greater among those with body mass index of 35 or more relative to individuals with healthy weights. The findings suggest that obesity is a risk factor for MM and a contributor to the rising incidence rates of MM among African Americans.  link to online article

Laboratory studies show that air pollutants can increase insulin resistance, but epidemiologic evidence on whether air pollution affects diabetes incidence is conflicting. We assessed traffic-related nitrogen dioxide (NO2) levels in relation to the incidence of type 2 diabetes in the BWHS. Based on 4387 participants who were diagnosed with diabetes during 1995 to 2011, we found no evidence of an increase in diabetes associated with levels of NO2.  link to online article

The participation of African-Americans in research involving biospecimens used in genetic studies (such as saliva/mouthwash or blood samples) has generally been low. However, in the BWHS, the response rate to an invitation to submit a saliva/mouthwash sample (which is a source of DNA) was high, 51%. The response rate was highest among older women and women who were health conscious, as indicated by a recent visit to a doctor or having had cancer screening (mammography, colonoscopy, PAP smear). The response in the BWHS is encouraging given published findings of low overall participation rates of African-Americans in genetic studies.  link to online article

In a collaborative project of four large studies of African American women, we examined associations between smoking and breast cancer. Results differed by menopausal status. Postmenopausal women who had smoked most heavily were estimated to have a 15% greater risk of breast cancer than postmenopausal women who had never smoked. Other studies have found similar results. By contrast, among premenopausal women, smokers had lower risk than nonsmokers, a finding that has not been observed before and requires confirmation.  link to online article

Animal studies and epidemiologic studies in children have suggested that air pollution might contribute to weight gain. We investigated the association between air pollution and weight gain over 16 years of follow-up in the BWHS. The air pollutants assessed were fine particulate matter, ozone, and nitrogen dioxide, with levels based on measurements from a variety of sources. Our analyses suggested that air pollution does not increase weight gain.  link to online article

Previous studies have found an association between uterine leiomyomata (fibroids in the womb) and cancer of the uterus. In the BWHS, based on 300 incident cases of endometrial cancer identified during follow-up, women with a history of uterine leiomyomata had a higher incidence of endometrial cancer compared to woman without such a history. The strongest association was observed for cancer diagnosed within two years of the diagnosis of uterine leiomyomata, suggesting that women with uterine leiomyomata may be under greater surveillance for cancer. Confirmation of these findings is needed.  link to online article

Previous studies have found that a woman’s personal socioeconomic status (e.g., income and education) is related to her risk of developing asthma, with higher risk among women with fewer socioeconomic resources. It is possible that neighborhood socioeconomic status could also contribute to risk of developing asthma, for example in neighborhoods with more older buildings with higher levels of allergens. In a study in the BWHS that included 1520 women who developed asthma during follow-up, individual and neighborhood socioeconomic status were both assessed in relation to asthma incidence. Lower personal socioeconomic status was associated with increased asthma risk, as has been seen in other studies, whereas there was no association of neighborhood with risk.  link to online article

Low neighborhood socioeconomic status (SES) is associated with higher risk of cardiovascular disease (CVD), such as heart attacks. We assessed neighborhood SES in relation to several CVD biomarkers in blood samples provided by BWHS participants. The blood samples of 418 BWHS participants were assayed for C-reactive protein (CRP), hemoglobin A1C (hgA1C), and high-density lipoprotein (HDL) cholesterol.  Women living in neighborhoods with lowest SES had the least favorable biomarker levels. These results suggest that neighborhood environments may affect physiological processes within residents independently of individual SES.  link to online article

Low neighborhood socioeconomic status (SES) is associated with poorer health. We assessed the relation of neighborhood SES to mortality in the BWHS.  Based on 2,598 deaths during 1995-2011, lower neighborhood SES was associated with increased all-cause and cancer mortality irrespective of individual level of education. The presence of the association even among women with high levels of education suggests that high individual SES may not overcome the unfavorable influence of neighborhood deprivation on mortality.  link to online article

We assessed a genetic pathways that might be involved in breast cancer occurrence, namely the fibroblast growth factor receptor (FGFR) signaling pathway. We compared genetic variants in this pathway among women with and without breast cancer in a collaborative study of the BWHS with three other studies of African American women. We found an association of the FGFR2 gene with estrogen receptor positive breast cancer, and an association of the FGFR1 gene with estrogen receptor negative breast cancer. Thus, different genes in the same pathway may be associated with different breast cancer subtypes.  link to online article

Breast cancer is not a single disease but rather is made up of various subtypes.  Based on breast cancer tumor tissue from a consortium of studies of breast cancer in Black women that included the BWHS, we compared classification into subtypes by a three-biomarker immunohistochemistry (IHC) method with classification by an RNA-based method and classification by estrogen and progesterone receptor status; the latter classification is commonly used in hospitals to guide treatment.  The IHC-based method had reasonable accuracy for distinguishing the basal-like subtype (which has a poorer prognosis) from non-basal like cancers, but addition biomarkers were needed to distinguish other subtypes.  link to online article

A woman’s family history of various cancers may be related to her chance of developing breast cancer, but evidence has been conflicting. We assessed the relation of a woman’s first-degree family history (in her mother, father, sisters, brothers, or children) of breast cancer and several other cancers (e.g., prostate, lung, colon, cervix) to her risk of developing breast cancer. This was a collaborative study of the BWHS with three other studies that included African American women.  First degree family history of breast cancer was associated with a 70% increase in a woman’s own risk of developing breast cancer, whereas having a family history of both breast cancer and prostate cancer was associated with an increase three times that great. These findings suggest that greater surveillance and screening for breast cancer may be needed for women with a family history of both breast and prostate cancer.  link to online article

Vitamin D deficiency is more common among African Americans than among other racial groups. We assessed whether vitamin D-related genetic pathways are involved in breast cancer risk in the BWHS and three other studies of African American women. To do so, we compared genetic variants in vitamin-D related pathways among women with and without breast cancer.  Several genetic variants were related to breast cancer risk, and one in particular was related to estrogen receptor negative breast cancer, a subtype that occurs more commonly among African American women. These results support a possible role for vitamin D in the occurrence of breast cancer subtypes.  link to online article

Estrogen receptor negative (ER-) breast cancer is a subtype of breast cancer that occurs more commonly in black women than white women. Because ER- cancer includes “triple negative” breast cancer, a subtype that has a poorer prognosis than other subtypes, there has been a search for genetic variants that may be associated with higher or reduced risk of ER- cancer. In the present collaborative study that involved BWHS and three other studies of African American women, we assessed genetic variants in a pathway, mTOR that might play a role in the development of breast cancer. Several variants were found to be related to risk of ER- breast cancer. If confirmed, these findings suggest a mechanism that might help to explain the occurrence of ER- breast cancer in black women.  link to online article

Medications with estrogen together with progestin, such as PremPro, are used to treat menopausal symptoms. Their use has been associated with increased incidence of estrogen receptor-positive (ER+) breast cancer in White women. Using data from the BWHS and three other large studies of Black women, we found that the incidence of ER+ cancer was increased in users of estrogen with progestin, but not in users of medications that contained estrogen alone. There is now a great deal of evidence suggesting a cause-effect relationship between combination therapy and ER+ breast cancer. A decrease in use would be expected to reduce the number of ER+ cancers. Women of any ethnic group using drugs containing estrogen with progestin for the relief of menopausal symptoms should use them for as short a time as possible.  link to online article

Numerous genetic variants are associated with body mass index (a measure of body size). It has also been found that people born with a low birth weight have an increased risk of disorders that involve weight control, which suggests that normal regulation of body weight is disrupted in people with low birth weight.  We found that certain central nervous system genetic variants associated with weight affected the relation of birth weight to adult body mass index in the BWHS. These results support the theory that low-birth weight disrupts mechanisms of body weight regulation.  link to online article

Inflammation may be a pathway involved in the development of endometrial cancer (cancer of the lining of the womb). Fatty fish contain a substance, a “fatty acid”, that is thought to reduce inflammation. If this is so, fish consumption might lower risk of developing endometrial cancer.  We assessed this possibility in the BWHS and found that fish intake was related only weakly to the overall incidence of endometrial cancer.  There was a hint of a lower risk for fish consumption among leaner women, but assessment of this possibility will require larger numbers.  link to online article

Exposure to a component of air pollution called fine particulate matter (PM2.5) has been linked to increases in insulin resistance and blood pressure, raising the possibility that PM2.5 could increase the incidence of diabetes and hypertension. In a study of BWHS participants living in 56 metropolitan areas across the US, we first estimated PM2.5 levels and then assessed whether levels were related to the occurrence of type 2 diabetes or hypertension. Our analysis suggested that PM2.5 dose not increase the incidence of either condition.  link to online article

Cancer of the endometrium (the lining of the womb) occurs more commonly among white women who are overweight or obese or have type 2 diabetes, but whether this is the case among African American women has received little study.  In an assessment of these issues within the BWHS, we found that the incidence of endometrial cancer increased as body mass index increased.  There was also an increased risk of this cancer among women who had diabetes.  Thus, overweight and diabetes appear to have similar effects on endometrial cancer incidence in black and white women.  link to online article

2015

We investigated genetic variation in hormone pathways in relation to risk of breast cancer overall and of specific subtypes, using genetic information from the BWHS and three other large studies of Black women.  We identified several genes in hormone pathways that were associated with risk of breast cancer overall or of the estrogen receptor negative subtype, which occurs more commonly among Black women. These results provide clues about mechanisms involved in breast cancer occurrence.  link to online article

Some studies have found associations of uterine fibroids with increased risk of cancer of the uterus (womb). We found that a history of uterine fibroids was associated with an increase in the risk of endometrial cancer (cancer of the lining of the womb) in the BWHS. This association has plausibility because both conditions are related to female hormone levels.  link to online article

African American women experience higher rates of ER- (estrogen receptor-negative) breast cancer, an aggressive type of breast cancer, than white women. African American women also, on average, have an earlier age at menarche (first period) than other U.S. women. Causes of ER- breast cancer have not been clearly established. Data from the BWHS and three other  studies with large numbers of African American women (the AMBER Consortium) were used to assess the relationship of age at menarche with risk of ER- and ER+ breast cancer. Risk of ER+ breast cancer was increased among women with longer intervals between menarche and the birth of the first child, whereas later menarche was associated with lower risk of ER- breast cancer regardless of childbearing. These differences suggest that the biologic pathways influencing risk of ER- and ER+ breast cancer may differ.  link to online article

Data from the BWHS and three other studies were used to assess the relationships of obesity and body fat distribution to different subtypes of breast cancer, including triple negative (TN) cancer, which occurs more commonly in Black women. Relationships differed according to the subtype of cancer and menopausal status. Higher body mass index was associated with decreased risk of postmenopausal estrogen receptor positive (ER+) cancer and with decreased risk of postmenopausal TN cancer. Higher body mass index around the age of 18 was associated with increased risk of premenopausal ER+ cancer and all subtypes of postmenopausal cancer. High waist-to-hip ratio, a measure of body fat distribution around the waist, was associated with increased risk of ER+ tumors. Different biologic mechanisms may be at work and more research is needed to understand the interplay between weight, body fat distribution, and breast cancer.  link to online article

Previous studies have found that women who have recently used oral contraceptives have a higher risk of breast cancer, which dissipates after use ceases. This large study, based on the BWHS and three other studies, examined the association between oral contraceptive use and specific subtypes of breast cancer, namely estrogen receptor positive, estrogen receptor negative, and triple negative breast cancer. Long-term and recent oral contraceptive use were associated with increased risk of all subtypes of cancer. The risk decreased over time after use was halted.  link to online article

In an assessment of whether dietary intake is associated with risk of dying, information on food intake provided by Black Women’s Health Study participants in 1995 and 2001 was used to define several dietary patterns, such as the “Western” pattern. The Western pattern is a common pattern in the U.S., characterized by high intake of meat, fats, and sweets. The death rate was higher among BWHS participants with a Western type of diet whereas it was lower among women whose diets were high in whole grains, fruits, and vegetables. These findings are similar to results in other populations and strengthen the evidence that type of dietary intake can increase or decrease the risk of dying.  link to online article

In 2005 BWHS participants reported information on whether and how long they had worked night shifts. Based on follow-up through 2013, the incidence of type 2 diabetes in the BWHS was greater among women who had worked a night shift for at least 10 years than among women who had not worked night shifts. The relationship was present in women who were overweight or obese as well as in thinner women, indicating that the mechanism for the increase was not through weight. A possible mechanism may involve sleep disturbances, which are increasingly being associated with adverse health effects.  link to online article

With BWHS data on smoking (“active”) and exposure to the smoke of others (“passive”), we examined the development of adult-onset asthma among  past smokers, current smokers, non-smokers who were exposed to the smoke of others (passive smokers), and non-smokers  never exposed to the smoke of others. Current active smoking was associated with the greatest increase in risk of adult-onset asthma. Passive smokers also experienced a higher risk but less than that of active smokers. These results suggest that avoiding smoking and reducing exposure to tobacco smoke could help to prevent the development of adult-onset asthma.  link to online article

Depression can affect the production of female hormones, which are thought to be involved in the development of uterine leiomyomata. In a study in the BWHS, the incidence of uterine fibroids was a little higher among women who reported more depressive symptoms than in women with fewer symptoms. This finding supports the idea that disruption of female hormones can influence risk of uterine fibroids.  link to online article

Breast cancer prediction models that are currently used underestimate risk of breast cancer for African American women, resulting in lower rates of recruitment into breast cancer prevention trials. Based on data collected from Black Women’s Health Study (BWHS) participants from 1995 to 2005, BWHS developed a prediction model that includes more factors than used in previous models.  The model was then tested in BWHS data from 2006-2011. The results suggested an improvement on current prediction models among African American women. Use of the new model could result in an increase in the number of Black women eligible for breast cancer prevention trials, which in turn would ensure that new prevention methods are applicable to African American women.  link to online article

The BWHS and other studies have previously shown that childbearing is associated with weight gain in the years following a pregnancy. In an analysis of the association of breast feeding with weight gain after pregnancy, BWHS participants who had a body mass index less than 30 before pregnancy and who breastfed their babies after the pregnancy gained a little less weight than similar women who did not breast feed, but this was not the case among heavier women who breast fed their babies. While the beneficial effect of breastfeeding on the health of babies is clear, the effect of breastfeeding on weight gain is likely very small.  link to online article

Sarcoidosis, an inflammatory autoimmune disease that can affect the lungs and other organs, disproportionally affects Black women. Overweight and obesity causes inflammation. BWHS data was used to examine whether there is an association between weight and sarcoidosis. Weight gain and obesity were both associated with increased incidence of sarcoidosis. While plausible, this is the first report of such associations and they need to be confirmed in other studies.  link to online article

The Endometrial Cancer Consortium combines data from 18 separate studies, including the BWHS, to assess risk factors for endometrial cancer. Based on 8,801 cases of endometrial cancer, use of IUDs of various types was associated with reduced risk of endometrial cancer. To fully understand the biology of the decrease in risk, additional study is needed. In addition, further study of the types of IUDs currently available in the US is needed.  link to online article