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Michelle D Holmes

Publications and source records attributed to Michelle D Holmes.

34 records · Page 2Linked to original sources
PubMed2005

High school dietary dairy intake and teenage acne.

BACKGROUND: Previous studies suggest possible associations between Western diet and acne. We examined data from the Nurses Health Study II to retrospectively evaluate whether intakes of dairy foods during high school were associated with physician-diagnosed severe teenage acne. METHODS: We studied 47,355 women who completed questionnaires on high school diet in 1998 and physician-diagnosed severe teenage acne in 1989. We estimated the prevalence ratios and 95% confidence intervals of acne history across categories of intakes. RESULTS: After accounting for age, age at menarche, body mass index, and energy intake, the multivariate prevalence ratio (95% confidence intervals; P value for test of trend) of acne, comparing extreme categories of intake, were: 1.22 (1.03, 1.44; .002) for total milk; 1.12 (1.00, 1.25; .56) for whole milk; 1.16 (1.01, 1.34; .25) for low-fat milk; and 1.44 (1.21, 1.72; .003) for skim milk. Instant breakfast drink, sherbet, cottage cheese, and cream cheese were also positively associated with acne. CONCLUSION: We found a positive association with acne for intake of total milk and skim milk. We hypothesize that the association with milk may be because of the presence of hormones and bioactive molecules in milk.

Acne Vulgaris↗
PubMed2005

Racial differences in premenopausal endogenous hormones.

Differences in breast cancer incidence across racial groups are well documented. African Americans have the highest rates of premenopausal breast cancer and Asians have lower breast cancer rates across all age groups. We hypothesized that levels of premenopausal endogenous hormones and growth factors, risk factors that have been predictive of breast cancer, would differ by race. Using a cross-sectional study design, we tested this hypothesis in the Nurses' Health Study II. We assayed estradiol, progesterone, prolactin, sex hormone binding globulin (SHBG), insulin-like growth factor-I (IGF-I), and IGFBP-3 in 111 African American and 111 Asian American women, matched to 111 Caucasian women on age, day of luteal phase, and day, time, and fasting status at blood collection. We analyzed the association between race and hormone levels using robust linear regression methods. In multivariate models, compared with Caucasians, African Americans had 18% higher levels of estradiol (P < 0.01), 17% higher free estradiol (P < 0.01), 11% lower SHBG (P = 0.05), 11% higher IGF-I (P < 0.01), 25% higher free IGF-I (P < 0.01), and 9% lower IGFBP-3 (P < 0.01) levels. In multivariate models, compared with Caucasian women, Asian Americans had 22% higher calculated free estradiol (P < 0.01), 31% lower SHBG (P < 0.01), and 25% higher free IGF-I (P < 0.01) levels. No racial differences were found in progesterone and prolactin levels. Our study showed hormone differences consistent with breast cancer risk between Caucasians and African Americans but inconsistent with breast cancer risk between Asian Americans and Caucasians. Further research is needed to explore differences across racial groups and the link between endogenous hormones and breast cancer risk.

Adult↗
PubMed2004

Association of hormone replacement therapy to estrogen and progesterone receptor status in invasive breast carcinoma.

BACKGROUND: Observational studies and randomized trials have demonstrated that hormone replacement therapy (HRT) increases the recipient's risk of developing breast carcinoma. Because it is known that some breast malignancies are hormonally responsive and that others are not, it has been hypothesized that HRT may be associated with the development of estrogen receptor (ER)-positive/progesterone receptor (PR)-positive breast carcinoma more so than with the development of ER-negative/PR-negative breast carcinoma. METHODS: The Nurses' Health Study is a prospective cohort study that enrolled 121,700 female registered nurses ages 30-55 years in 1976. In the current study, the authors analyzed 2548 malignancies that developed among eligible postmenopausal women in that cohort between 1980 and 2000 and for which data on ER and PR status were available. RESULTS: Compared with women who had never used HRT, current long-term users of HRT were more likely to develop ER-positive/PR-positive breast carcinoma (multivariate risk ratio [RR], 1.80; 95% confidence interval [CI], 1.52-2.12) but were not any more likely to develop ER-negative/PR-negative disease (multivariate RR, 1.00; 95% CI, 0.72-1.39). This effect grew stronger with increasing duration of current HRT use and was also more pronounced among women with body mass index < 25 kg/m2. Furthermore, the association between HRT use and ER-positive/PR-positive disease was stronger among patients receiving combined HRT (CHRT) regimens, which included estrogen and progesterone, than among users of estrogen alone (ERT). In addition, tumors tended to develop more quickly in current users of CHRT than in ERT users. CONCLUSIONS: The finding that current users of HRT were more likely to develop ER-positive/PR-positive tumors than they were to develop ER-negative/PR-negative ones suggests that both endogenous and exogenous hormonal factors may influence breast tumor characteristics. In analyses of the effects of hormonal factors on breast tumor development, ER-positive/PR-positive tumors and ER-negative/PR-negative tumors should be considered separately from each other.

Adult↗
PubMed2004

Does diet affect breast cancer risk?

The role of specific dietary factors in breast cancer causation is not completely resolved. Results from prospective studies do not support the concept that fat intake in middle life has a major relation to breast cancer risk. However, weight gain in middle life contributes substantially to breast cancer risk. Alcohol is the best established dietary risk factor, probably by increasing endogenous estrogen levels. Hypotheses relating diet during youth to risk decades later will be difficult to test. Nevertheless, available evidence is strong that breast cancer risk can be reduced by avoiding weight gain during adult years, and by limiting alcohol consumption.

Animals↗
PubMed2004

Caregiving stress, endogenous sex steroid hormone levels, and breast cancer incidence.

Stress is hypothesized to be a risk factor for breast cancer. The authors examined associations of hours of, and self-reported levels of stress from, informal caregiving with prospective breast cancer incidence. Cross-sectional analyses of caregiving and endogenous sex steroid hormones were also conducted. In 1992 or 1996, 69,886 US women from the Nurses' Health Study, aged 46-71 years at baseline, answered questions on informal caregiving; 1,700 incident breast cancer cases accrued over follow-up to 2000. A subset of 665 postmenopausal women not taking exogenous hormones returned a blood sample in 1990. Numbers of hours of care provided to an ill adult or to a child were each summed and analyzed as 0 (reference), 1-14, and >/=15 per week. Cox proportional hazards models were used in prospective analyses and linear models in cross-sectional analyses. High numbers of caregiving hours and self-reported stress did not predict a higher incidence of breast cancer. However, compared with women providing no adult care, women providing >/=15 hours of adult care (median, 54) had significantly lower levels of estradiol (geometric mean, 9.21 pg/ml vs. 7.46 pg/ml (95% confidence interval: 6.36, 8.76)) and bioavailable estradiol (geometric mean, 1.86 pg/ml vs. 1.35 pg/ml (95% confidence interval: 1.00, 1.82)). Stress from caregiving did not appear to increase breast cancer risk.

Aged↗
PubMed2004

Functional impact of breast cancer by age at diagnosis.

PURPOSE: To explore changes in physical and psychosocial function before and after breast cancer by age at diagnosis. PATIENTS AND METHODS: A total of 122,969 women from the Nurses' Health Study (NHS) and NHS 2, ages 29 to 71 years, who responded to pre- and postfunctional status assessments were included; 1,082 women were diagnosed with breast cancer between 1992 and 1997. Functional status was measured using the Medical Outcomes Study Short Form 36 (SF-36). Mean change in health-related quality of life (HRQoL) scores was computed across categories representing the combination of incident breast cancer (yes or no) and age at diagnosis (< or = 40, 41 to 64, or 65+ years). RESULTS: Compared with women < or = 40 years without breast cancer, women with breast cancer experienced significant functional declines. Young (age < or = 40) women who developed breast cancer experienced the largest relative declines in HRQoL (as compared with middle-aged and elderly women) in multiple domains including physical roles (-18.8 v -11.5 and -7.5 points, respectively), bodily pain (-9.0 v -2.7 and -2.7 points), social functioning (-11.3 v -4.3 and -4.4 points) and mental health (-3.1 v 0.0 and +0.4 points). Much of the decline in HRQoL among elderly (age > or = 65) women with breast cancer was age related. CONCLUSION: Young women may fare worse than middle-aged or elderly women in both physical and psychosocial dimensions after breast cancer diagnosis. The needs of women facing breast cancer may be better understood within a life stage framework.

Adult↗
PubMed2004

Dietary carbohydrates, fiber, and breast cancer risk.

Dietary fiber, fiber fractions, carbohydrate, glycemic index, and glycemic load were prospectively assessed five times over 18 years with a validated food frequency questionnaire in relation to breast cancer risk among 88,678 women (aged 34-59 years at baseline) in the Nurses' Health Study. Incident breast cancer occurred in 4,092 of these women between 1980 and 1998. The authors observed no material association between carbohydrate intake, glycemic index and glycemic load, total dietary fiber intake, and breast cancer risk. The relative risks for the highest versus the lowest quintile of intake were 0.97 (95% confidence interval (CI): 0.87, 1.08) for carbohydrates, 1.08 (95% CI: 0.97, 1.19) for glycemic index, 0.99 (95% CI: 0.89, 1.10) for glycemic load, and 0.98 (95% CI: 0.87, 1.11) for fiber. The relative risk comparing those in the highest 0.7% of fiber intake (>30 g/day) with those in the lowest 10% of fiber intake (< or =10 g/day) was 0.68 (95% CI: 0.43, 1.06). Analyses stratified by menopausal status and body mass index also showed no clear risk pattern. In this cohort of middle-aged women, no overall association was found for dietary carbohydrates, glycemic index and glycemic load, and breast cancer risk. This study also confirmed the lack of an overall association between intake of fiber and fiber types and breast cancer risk observed in other prospective studies.

Adult↗
PubMed2004

Risk factors for breast cancer according to estrogen and progesterone receptor status.

BACKGROUND: Evaluations of epidemiologic risk factors in relation to breast cancer classified jointly by estrogen receptor (ER) and progesterone receptor (PR) status have been inconsistent. To address this issue, we conducted a prospective evaluation of risk factors for breast cancer classified according to receptor status. METHODS: During 1 029 414 person-years of follow-up of 66 145 women participating in the Nurses' Health Study from 1980 through 2000, we identified 2096 incident cases of breast cancer for which information on ER/PR status was available: 1281 were ER+/PR+, 318 were ER+/PR-, 80 were ER-/PR+, and 417 were ER-/PR-. We fit a log-incidence model of breast cancer and used polychotomous logistic regression to compare coefficients for breast cancer risk factors in patients with different ER/PR status. To test for differences in risk factor odds ratios based on marginal ER/PR categories, we evaluated ER status controlling for PR status and vice versa. The predictive ability of our log-incidence model to discriminate between women who would develop ER+/PR+ breast cancer and those who would not (and similarly for ER-/PR- breast cancer) was evaluated by using receiver operator characteristic curve analysis. All statistical tests were two-sided. RESULTS: We observed statistically significant heterogeneity among the four ER/PR categories for some risk factors (age, menopausal status, body mass index [BMI] after menopause, the one-time adverse effect of first pregnancy, and past use of postmenopausal hormones) but not for others (benign breast disease, family history of breast cancer, alcohol use, and height). The one-time adverse association of first pregnancy with incidence was present for PR- but not for PR+ tumors after controlling for ER status (P =.007). However, the association of BMI after menopause with incidence was present for PR+ but not PR- tumors (P =.005). Statistically significant differences in the incidence of ER+ and ER- tumors were seen with age, both before and after menopause (P =.003), and with past use of postmenopausal hormones (P =.01). Area under the receiver operator characteristic curve, adjusted for age, was 0.64 (95% confidence interval [CI] = 0.63 to 0.66) for ER+/PR+ tumors and 0.61 (95% CI = 0.58 to 0.64) for ER-/PR- tumors. CONCLUSIONS: Incidence rates and risk factors for breast cancer differ according to ER and PR status. Thus, to accurately estimate breast cancer risk, breast cancer cases should be divided according to the ER and PR status of the tumor.

Adult↗
PubMed2004

Prostate cancer mortality in Connecticut, Iowa and New Mexico African American men.

We sought to assess trends in prostate cancer incidence, treatment and mortality in African American men by means of analysis of prostate cancer data from three states, Connecticut, Iowa and New Mexico, all participants in the Surveillance, Epidemiology, and End Results (SEER) Program. Compared with levels before prostate specific antigen (PSA) testing, prostate cancer incidence increased in all three states after widespread testing. For men diagnosed with localized or regional prostate cancer, the respective increases in radical prostatectomy in Connecticut, Iowa, and New Mexico were 3.2, 2.3, and 4.9 times pre-test levels. Age-standardized mortality in Connecticut and Iowa increased slightly; in New Mexico the 104.7 deaths per 100,000 in 1979-1986, 62.1 in 1987-1990, dropped to 47.6 in 1991-1998, an amount of decline that was statistically significant. Introduction of PSA testing influenced early detection and treatment of prostate cancer in all three states. Although decline in prostate cancer mortality in New Mexico over time may be linked with use of the PSA test and definitive therapy, the relationship among these factors, and thus the proper treatment for the early stages of this condition, is unclear on the basis of these data.

Black or African American↗
PubMed2003

Meat, fish and egg intake and risk of breast cancer.

Intakes of animal protein, meat, and eggs have been associated with breast cancer incidence and mortality in ecological studies, but data from long-term prospective studies are limited. We therefore examined these relationships in the Nurses' Health Study. We followed 88,647 women for 18 years, with 5 assessments of diet by food frequency questionnaire, cumulatively averaged and updated over time. We calculated the relative risks (RR) and 95% confidence intervals (95% CI) for risk of developing invasive breast cancer, over categories of nutrient and food intake. During follow-up, 4,107 women developed invasive breast cancer. Compared to the lowest quintile of intake, the RR and 95% CI for the highest quintile of intake were 1.02 (0.92-1.14) for animal protein, 0.93 (0.83-1.05) for red meat and 0.89 (0.79-1.00) for all meat. Results did not differ by menopausal status or family history of breast cancer. We found no evidence that intake of meat or fish during mid-life and later was associated with risk of breast cancer.

Adult↗
PubMed2003

Plasma folate, vitamin B6, vitamin B12, homocysteine, and risk of breast cancer.

BACKGROUND: In several epidemiologic investigations, folate intake has appeared to reduce the elevated risk of breast cancer associated with moderate alcohol consumption. However, data relating plasma folate levels to breast cancer risk are sparse. We investigated the association between plasma folate and other vitamins with breast cancer in a prospective, nested case-control study. METHODS: Blood samples were obtained during 1989 and 1990 from 32 826 women in the Nurses' Health Study who were followed through 1996 for the development of breast cancer. We identified 712 breast cancer case patients and selected 712 individually matched control subjects. Dietary information was obtained using food frequency questionnaires given in 1980, 1984, 1986, and 1990. Logistic regression was used to estimate the relative risks (RRs) of breast cancer (after adjustment for potential risk factors), and a generalized linear model was used to calculate the Pearson correlation coefficients between plasma estimates of folate, vitamin B(6), vitamin B(12), and homocysteine, and intakes of folate, vitamin B(6), and vitamin B(12). All statistical tests were two-sided. RESULTS: The multivariable RR comparing women in the highest quintile of plasma folate with those in the lowest was 0.73 (95% confidence interval [CI] = 0.50 to 1.07; P(trend) =.06). The inverse association between plasma folate and breast cancer risk was highly statistically significant among women consuming at least 15 g/day (i.e., approximately 1 drink/day) of alcohol (multivariable RR = 0.11, 95% CI = 0.02 to 0.59 for highest versus lowest quintile) in contrast with that of women consuming less than 15 g/day (multivariable RR = 0.72, 95% CI = 0.49 to 1.05). The multivariable RR comparing women in the highest quintile of plasma vitamin B(6) levels with those in the lowest quintile was 0.70 (95% CI = 0.48 to 1.02; P(trend) =.09). Plasma vitamin B(12) levels were inversely associated with breast cancer risk among premenopausal women (multivariable RR = 0.36, 95% CI = 0.15 to 0.86 for highest versus lowest quintile) but not among postmenopausal women. Plasma homocysteine was not associated with breast cancer risk. CONCLUSIONS: Higher plasma levels of folate and possibly vitamin B(6) may reduce the risk of developing breast cancer. Achieving adequate circulating levels of folate may be particularly important for women at higher risk of developing breast cancer because of higher alcohol consumption.

Adult↗
PubMed2002

Intake of dairy products, calcium, and vitamin d and risk of breast cancer.

BACKGROUND: Laboratory data suggest that calcium and vitamin D, found at high levels in dairy products, might reduce breast carcinogenesis. However, epidemiologic studies regarding dairy products and breast cancer have yielded inconsistent results. We examined data from a large, long-term cohort study to evaluate whether high intake of dairy products, calcium, or vitamin D is associated with reduced risk of breast cancer. METHODS: We followed 88 691 women in the Nurses' Health Study cohort from the date of return of their food-frequency questionnaire in 1980 until May 31, 1996. Dietary information was collected in 1980 and updated in 1984, 1986, 1990, and 1994. We identified 3482 women (premenopausal = 827, postmenopausal = 2345, and uncertain menopausal status = 310) with incident invasive breast cancer. We used pooled logistic regression to estimate multivariable relative risks (RRs) using 2-year time increments. The RRs and 95% confidence intervals (CIs) were calculated for each category of intake compared with the lowest intake group. All statistical tests were two-sided. RESULTS: Intakes of dairy products, calcium, or vitamin D were not statistically significantly associated with breast cancer risk in postmenopausal women. In premenopausal women, however, consumption of dairy products, especially of low-fat dairy foods and skim/low-fat milk, was inversely associated with risk of breast cancer. The multivariable RRs comparing highest (>1 serving/day) and lowest ( 800 mg/day versus 500 IU/day versus <or=150 IU/day; RR = 0.72, 95% CI = 0.55 to 0.94), and lactose (quintile 5 versus quintile 1; RR = 0.68, 95% CI = 0.54 to 0.86] also had inverse associations with premenopausal breast cancer risk. By taking into account supplemental calcium and vitamin D intake, we found that association with calcium was due mainly to dairy sources whereas the association with vitamin D may be independent of dairy intake. CONCLUSIONS: We found no association between intake of dairy products and breast cancer in postmenopausal women. Among premenopausal women, high intake of low-fat dairy foods, especially skim/low-fat milk, was associated with reduced risk of breast cancer. Similar inverse associations were seen with components (calcium and vitamin D) of dairy foods, but their independent associations with breast cancer are difficult to distinguish.

Breast Neoplasms↗
PubMed2002

Social networks and health-related quality of life in breast cancer survivors: a prospective study.

PURPOSE: To examine prospectively the influence of social networks on health-related quality of life (HRQoL) among breast cancer survivors. METHODS: Social networks and HRQoL were assessed among women free of breast cancer in the Nurses' Health Study (NHS). Women who developed breast cancer over a 4-year follow-up (n=708) completed detailed questions related to treatment together with an assessment of general and cancer-specific HRQoL. RESULTS: On average, socially isolated women were more adversely affected by breast cancer--their role function was lower by 14 points, vitality lower by 7 points, and physical function lower by 6 points compared to the most socially integrated women. CONCLUSION: Prediagnosis level of social integration is an important factor in future HRQoL among breast cancer survivors, and appears to explain more of the variance in HRQoL than treatment or tumor characteristics. Rehabilitation programs should incorporate interventions that address the availability of adequate social support among breast cancer survivors.

Aged↗
PubMed2002

Dietary correlates of plasma insulin-like growth factor I and insulin-like growth factor binding protein 3 concentrations.

Plasma levels of insulin-like growth factor I (IGF-I) have been associated with risk of several cancers. Although protein-calorie malnutrition is known to decrease IGF-I levels, few published studies have related diet to IGF-I levels in well-nourished humans. We examined the cross-sectional association of plasma IGF-I and IGF-binding protein 3 (IGFBP-3) levels with intakes of alcohol, energy, macronutrients, micronutrients, and specific foods in 1037 healthy women. Adjusted mean hormone levels across categories of dietary variables were calculated by linear regression. Results were adjusted for non-dietary factors found to be associated with IGF levels. Total energy intake was positively associated with IGF-I levels when adjusted for covariates. Adjusted mean levels of IGF-I (ng/ml) across increasing quintiles of energy intake were 181, 185, 191, 199, and 195 (P for the linear trend = 0.006). In other multivariate analyses, energy-adjusted fat and carbohydrate intake had no association with IGF-I levels. The most consistent finding was a positive association between protein intake with circulating IGF-I concentration (174, 188, 201, 192, and 196 ng/ml across quintiles of protein intake; P = 0.002), which was largely attributable to milk intake. Adjusted mean levels of IGF-I (ng/ml) across increasing quartiles of milk intake were 183, 189, 188, and 200 (P = 0.01). Higher fat intake, in particular saturated fat, was associated with lower levels of IGFBP-3. We conclude that higher energy, protein, and milk intakes were associated with higher levels of IGF-I. These associations raise the possibility that diet could affect cancer risk through influencing IGF-I level.

Aged↗
PubMed2002

Lifestyle correlates of plasma insulin-like growth factor I and insulin-like growth factor binding protein 3 concentrations.

Plasma levels of insulin-like growth factor I (IGF-I) have been associated with risk of a number of cancers and other diseases. We examined the cross-sectional association of plasma IGF-I and IGF-binding protein 3 (IGFBP-3) levels with age, smoking, physical activity, and reproductive and menopausal factors in 1037 healthy women. Adjusted least-square mean hormone levels across categories of lifestyle factors were calculated by linear regression. Age was inversely associated with IGF-I levels. In multivariate analyses, a higher body mass index (BMI) was associated with higher IGFBP-3 levels (BMI <21 versus >/=29 kg/m(2), 3879 versus 4080 ng/ml; P for trend = 0.01). Current use of hormone replacement therapy (HRT) was associated with a lower IGF-I, with oral estrogen being associated with the lowest levels (non-use of HRT versus oral estrogen + progesterone versus oral estrogen: 181 versus 143 versus 116 ng/ml; P for all comparisons </= 0.005). Higher parity was also associated with lower levels of IGF-I (no pregnancies versus >/=4: 212 versus 180 ng/ml; P for trend = 0.003). We conclude that age and HRT use, particularly oral estrogen alone, were inversely associated with IGF-I levels. BMI was positively associated with IGFBP-3 levels. This is the first report of an inverse association of circulating IGF-I levels with parity. This association may represent one mechanism by which parity exerts its protective effect on some cancers.

Aged↗