The Women's Health Initiative Dietary Modification trial: overview and baseline characteristics of participants

Changes in Overall Diet Quality in Relation to Survival in Postmenopausal Women with Breast Cancer: Results from the Women's Health Initiative

BACKGROUND

Lifestyle factors are important for cancer survival. However, empirical evidence regarding the effects of dietary changes on mortality in breast cancer survivors is sparse.

OBJECTIVE

The objective was to examine the associations of changes in overall diet quality, indicated by the Healthy Eating Index (HEI)-2010 score, with mortality in breast cancer survivors.

DESIGN

This was a prospective cohort study from September 1993 through September 30, 2015.

PARTICIPANTS/SETTING

This study included 2,295 postmenopausal women who were diagnosed with invasive breast cancer and completed a food frequency questionnaire both before and after the diagnosis of breast cancer in the Women's Health Initiative.

MAIN OUTCOME MEASURES

The HEI-2010 score (maximum score of 100) was calculated based on consumption of 12 dietary components. The outcomes were mortality from all causes, breast cancer, and causes other than breast cancer.

STATISTICAL ANALYSES PERFORMED

Multivariable Cox proportional hazards models were used to estimate adjusted hazard ratios of mortality from all causes, breast cancer, and other causes.

RESULTS

Over 12 years of follow-up, 763 deaths occurred. Compared with women with relatively stable diet quality (±14.9% change in HEI-2010 score), women who decreased diet quality (≥15% decrease in HEI-2010 score) had a higher risk of death from breast cancer (adjusted hazard ratio 1.66, 95% CI 1.09 to 2.52). Increased diet quality (≥15% increase in HEI-2010 score) was not significantly associated with lower risk of death. These associations persisted after additional adjustment for change in body mass index.

CONCLUSIONS

Among women with breast cancer, decreased diet quality after breast cancer diagnosis was associated with higher risk of death from breast cancer.

Testing the Predictive Validity of the Healthy Eating Index-2015 in the Multiethnic Cohort: Is the Score Associated with a Reduced Risk of All-Cause and Cause-Specific Mortality?

The Healthy Eating Index-2015 (HEI-2015) was created to assess conformance of dietary intake with the Dietary Guidelines for Americans (DGA) 2015–2020. We assessed the association between the HEI-2015 and mortality from all-cause, cardiovascular disease (CVD), and cancer in the Multiethnic Cohort (MEC). White, African American, Native Hawaiian, Japanese American, and Latino adults (n > 215,000) from Hawaii and California completed a quantitative food-frequency questionnaire at study enrollment. HEI-2015 scores were divided into quintiles for men and women. Radar graphs were used to demonstrate how dietary components contributed to HEI-2015 scores. Mortality was documented over 17–22 years of follow-up. Hazard ratios (HRs) and 95% confidence intervals (CIs) were computed using Cox proportional hazards models. High HEI-2015 scores were inversely associated with risk of mortality from all-cause, CVD, and cancer for men and women (p-trend <0.0001 for all models). For men, the HRs (CIs) for all-cause, CVD, and cancer comparing the highest to the lowest quintile were 0.79 (0.76, 0.82), 0.76 (0.71, 0.82), and 0.80 (0.75, 0.87), respectively. For women, the HRs were 0.79 (0.76, 0.82), 0.75 (0.70, 0.81), and 0.84 (0.78, 0.91), respectively. These results, in a multiethnic population, demonstrate that following a diet aligned with the DGAs 2015–2020 recommendations is associated with lower risk of mortality from all-cause, CVD, and cancer.

A Low-Fat Dietary Pattern and Diabetes: A Secondary Analysis From the Women's Health Initiative Dietary Modification Trial

OBJECTIVE

We performed a secondary analysis to evaluate the effect of the Women's Health Initiative dietary intervention on incident diabetes and diabetes treatment in postmenopausal women.

RESEARCH DESIGN AND METHODS

A total of 48,835 women were randomized to a comparison group or an intervention group that underwent a behavioral/nutritional modification program to decrease fat and increase vegetable, fruit, and grain intake for an average of 8.1 years. Ninety-three percent of participants completed the intervention, and 71% participated in active follow-up through 30 September 2015 (median 17.3 years). We measured time to development of treated diabetes and progression from oral antihyperglycemic agents to insulin. Serum glucose and insulin were measured in a subsample of women (N = 2,324) at baseline and years 1, 3, and 6.

RESULTS

During the trial, intervention group women had lower rates of initiation of insulin therapy (hazard ratio [HR] 0.74 [95% CI 0.59, 0.94]; P = 0.01). Moreover, women with baseline waist circumference ≥88 cm (P interaction = 0.01) and worse metabolic syndrome scores (P interaction = 0.02) had the greatest reduction in risk of initiating insulin therapy. The decreased risk from the intervention was present during the cumulative follow-up (HR 0.88 [95% CI 0.78, 0.99]; P = 0.04). In participants with measured biomarkers (5.8% subsample) who had baseline glucose <100 mg/dL, the intervention reduced the risk of developing glucose ≥100 mg/dL by 25% (odds ratio 0.75 [95% CI 0.61, 0.93]; P = 0.008). Adjustment for weight change did not alter the results.

CONCLUSIONS

In this secondary analysis, a dietary intervention in postmenopausal women aimed at reducing fat and increasing intake of vegetables, fruits, and grains did not increase risk of diabetes and may have slowed progression.

The Combined Association of Modifiable Risk Factors with Breast Cancer Risk in the Women's Health Initiative

Although several modifiable risk factors have been independently associated with risk of breast cancer, few studies have investigated their joint association with breast cancer risk. Using a healthy lifestyle index (HLI) score, we assessed the association of a combination of selected modifiable risk factors (diet, alcohol, physical activity, BMI, and smoking) with risk of invasive breast cancer in the Women's Health Initiative (WHI). This study comprised 131,833 postmenopausal women, of whom 8,168 had breast cancer, who were enrolled in the WHI Observational Study or the WHI clinical trials. Cox proportional hazards regression was used to estimate the HRs and 95% confidence intervals (CI) for the association of the score with the risk of developing breast cancer overall and according to specific breast cancer clinicopathologic characteristics. There was a 4% reduction in the risk of breast cancer per unit increase in the HLI score. Compared with those with an HLI score in the lowest quintile level, those in the highest quintile level had 30%, 37%, and 30% lower risk for overall, ER⁺/PR⁺, and HER2⁺ breast cancer, respectively (HR = 0.70; 95% CI, 0.64-0.76; 0.63, 0.57-0.69; and 0.70; 0.55-0.90, respectively). We also observed inverse associations between the score and risk of breast cancer irrespective of nodal status, tumor grade, and stage of the disease. Most individual lifestyle factors were independently associated with the risk of breast cancer. Our findings support the view that promoting healthy lifestyle practices may be beneficial with respect to lowering risk of breast cancer among postmenopausal women. Cancer Prev Res; 11(6); 317-26. ©2018 AACRSee related editorial by Friedenreich and McTiernan, p. 313.

Alcohol and oestrogen metabolites in postmenopausal women in the Women's Health Initiative Observational Study

Background:

Alcohol consumption is associated with an increased risk of several cancers. Potential mechanisms include altered oestrogen metabolism. Parent oestrogens metabolise into alternate pathways of oestrogen metabolites that may have variable effects on cancer pathogenesis. We examined associations of alcohol consumption with circulating oestrogen/oestrogen metabolites in postmenopausal women in the Women’s Health Initiative (WHI)-Observational Study (OS).

Methods:

We conducted a cross-sectional analysis of prediagnosis ovarian/endometrial cancer case-control data within WHI-OS (N=1864). Alcohol consumption was measured by validated food frequency questionnaire. Fasting serum parent oestrogens/oestrogen metabolites were assayed using liquid chromatography tandem mass-spectrometry. Geometric mean analyte concentrations (GM, pmol l⁻¹) were calculated by alcohol category using inverse-probability weighted linear regression, adjusting for venepuncture age/year, race, smoking, body mass index, years since menopause, oral contraceptive duration, caffeine intake, and physical activity.

Results:

There was evidence for a positive association between alcohol consumption and oestrone, oestradiol and 2-hydroxylation oestrogen metabolite concentrations among menopausal hormone therapy (MHT) users. We observed an association between liquor consumption and parent oestrogens among non-MHT users, who consumed larger doses of liquor than MHT users.

Conclusions:

Among postmenopausal women, the association between alcohol intake and parent oestrogen, but not oestrogen metabolite concentrations, may be influenced by MHT and type of alcohol.

Post-Stroke Cancer Risk among Postmenopausal Women: The Women's Health Initiative

BACKGROUND

Associations between a history of cancer and higher subsequent stroke risk have been established. However, whether a history of stroke is associated with higher subsequent cancer risk, especially for cancers with overlapping risk factors for stroke, is unknown. Therefore, we examined whether a history of stroke was associated with subsequent cancer risk and tumor site, by race/ethnicity, among postmenopausal women.

METHODS

Using data from 145,075 participants in the Women's Health Initiative observational study and clinical trials (1993-2014), we used Cox proportional hazards models to predict cancer risk, comparing women with and without a history of stroke. Bivariate and multivariate models were estimated, accounting for potential confounders and death as a competing risk.

RESULTS

Women with a history of stroke survived roughly 3 fewer years than women without such history. The average time between incident stroke and incident cancer was 4.8 years. In adjusted competing risk models, women with a history of stroke had a lower cancer risk compared with women without such a history (adjusted hazard ratio, 0.81; 95% CI, 0.75-0.88). The magnitude of the association between a history of stroke and time to incident cancer was similar across racial/ethnic groups.

DISCUSSION

Postmenopausal women with a history of stroke had a significantly lower risk of subsequent cancer compared with women with no history of stroke. Although the risk of certain cancers were greater for African American compared with White women, the association between a stroke history and cancer risk did not vary by race/ethnicity.

CONCLUSIONS

Postmenopausal women with a history of stroke, who survive long enough to develop cancer, have a lower risk of cancer than women without such a history. Future studies should examine whether behavioral or clinical characteristics explain and/or mediate this association.

Causal mediation analysis on failure time outcome without sequential ignorability

Mediation analysis is an important topic as it helps researchers to understand why an intervention works. Most previous mediation analyses define effects in the mean scale and require a binary or continuous outcome. Recently, possible ways to define direct and indirect effects for causal mediation analysis with survival outcome were proposed. However, these methods mainly rely on the assumption of sequential ignorability, which implies no unmeasured confounding. To handle the potential confounding between the mediator and the outcome, in this article, we proposed a structural additive hazard model for mediation analysis with failure time outcome and derived estimators for controlled direct effects and controlled mediator effects. Our methods allow time-varying effects. Simulations showed that our proposed estimator is consistent in the presence of unmeasured confounding while the traditional additive hazard regression ignoring unmeasured confounding produces biased results. We applied our method to the Women's Health Initiative data to study whether the dietary intervention affects breast cancer risk through changing body weight.

Low-fat Dietary Pattern and Pancreatic Cancer Risk in the Women's Health Initiative Dietary Modification Randomized Controlled Trial

Background

Observational studies suggest that diet may influence pancreatic cancer risk. We investigated the effect of a low-fat dietary intervention on pancreatic cancer incidence.

Methods

The Women's Health Initiative Dietary Modification (WHI-DM) trial is a randomized controlled trial conducted in 48 835 postmenopausal women age 50 to 79 years in the United States between 1993 and 1998. Women were randomly assigned to the intervention group (n = 19 541), with the goal of reducing total fat intake and increasing intake of vegetables, fruits, and grains, or to the usual diet comparison group (n = 29 294). The intervention concluded in March 2005. We evaluated the effect of the intervention on pancreatic cancer incidence with the follow-up through 2014 using the log-rank test and multivariable Cox proportional hazards regression model. All statistical tests were two-sided.

Results

In intention-to-treat analyses including 46 200 women, 92 vs 165 pancreatic cancer cases were ascertained in the intervention vs the comparison group (P = .23). The multivariable hazard ratio (HR) of pancreatic cancer was 0.86 (95% confidence interval [CI] = 0.67 to 1.11). Risk was statistically significantly reduced among women with baseline body mass indexes (BMIs) of 25 kg/m2 or higher (HR = 0.71, 95% CI = 0.53 to 0.96), but not among women with BMIs of less than 25 kg/m2 (HR = 1.62, 95% CI = 0.97 to 2.71, Pinteraction = .01).

Conclusions

A low-fat dietary intervention was associated with reduced pancreatic cancer incidence in women who were overweight or obese in the WHI-DM trial. Caution needs to be taken in interpreting the findings based on subgroup analyses.

Changes in the Inflammatory Potential of Diet Over Time and Risk of Colorectal Cancer in Postmenopausal Women

We examined the associations between changes in dietary inflammatory potential and risk of colorectal cancer (CRC) in 87,042 postmenopausal women recruited from 1993-1998 by the Women's Health Initiative, conducted in the United States. Food frequency questionnaire data were used to compute patterns of change in dietary inflammatory index (DII) scores and cumulative average DII scores over 3 years. Cox regression models were used to estimate hazard ratios for CRC risk. After a median of 16.2 years of follow-up, 1,038 CRC cases were diagnosed. DII changes were not substantially associated with overall CRC, but proximal colon cancer risk was higher in the proinflammatory-change DII group than in the antiinflammatory-stable DII group (hazard ratio = 1.32, 95% confidence interval: 1.01, 1.74). Among nonusers of nonsteroidal antiinflammatory drugs (NSAIDs) (Pinteraction = 0.055), the proinflammatory-stable DII group was at increased risk of overall CRC and proximal colon cancer. Also among nonusers of NSAIDs, risks of overall CRC, colon cancer, and proximal colon cancer were higher in the highest quintile compared with the lowest cumulative average DII quintile (65%, 61%, and 91% higher risk, respectively). Dietary changes toward, or a history of, proinflammatory diets are associated with an elevated risk of colon cancer, particularly for proximal colon cancer and among nonusers of NSAIDs.

Branched-chain amino acid, meat intake and risk of type 2 diabetes in the Women's Health Initiative

Knowledge regarding association of dietary branched-chain amino acid (BCAA) and type 2 diabetes (T2D), and the contribution of BCAA from meat to the risk of T2D are scarce. We evaluated associations between dietary BCAA intake, meat intake, interaction between BCAA and meat intake and risk of T2D. Data analyses were performed for 74 155 participants aged 50-79 years at baseline from the Women's Health Initiative for up to 15 years of follow-up. We excluded from analysis participants with treated T2D, and factors potentially associated with T2D or missing covariate data. The BCAA and total meat intake was estimated from FFQ. Using Cox proportional hazards models, we assessed the relationship between BCAA intake, meat intake, and T2D, adjusting for confounders. A 20 % increment in total BCAA intake (g/d and %energy) was associated with a 7 % higher risk for T2D (hazard ratio (HR) 1·07; 95 % CI 1·05, 1·09). For total meat intake, a 20 % increment was associated with a 4 % higher risk of T2D (HR 1·04; 95 % CI 1·03, 1·05). The associations between BCAA intake and T2D were attenuated but remained significant after adjustment for total meat intake. These relations did not materially differ with or without adjustment for BMI. Our results suggest that dietary BCAA and meat intake are positively associated with T2D among postmenopausal women. The association of BCAA and diabetes risk was attenuated but remained positive after adjustment for meat intake suggesting that BCAA intake in part but not in full is contributing to the association of meat with T2D risk.

Association between Dietary Energy Density and Incident Type 2 Diabetes in the Women's Health Initiative

BACKGROUND

Dietary energy density, or energy available in relation to gram intake, can inform disease risk.

OBJECTIVE

The objective of this study was to investigate the association between baseline dietary energy density and risk of incident type 2 diabetes in postmenopausal women.

DESIGN

Dietary energy density, weight status, and type 2 diabetes incidence were prospectively characterized in a large cohort of postmenopausal women participating in one or more clinical trials or an observational study.

PARTICIPANTS/SETTING

The study involved 161,808 postmenopausal women recruited to the Women's Health Initiative observational study or clinical trials at 40 centers across the United States between 1993 and 1998.

MAIN OUTCOME MEASURES

The primary outcome was incident type 2 diabetes.

STATISTICAL ANALYSES PERFORMED

The association between dietary energy density quintiles and incident diabetes was tested using Cox proportional hazards regression.

RESULTS

A total of 143,204 participants without self-reported diabetes at enrollment completed baseline dietary assessment and were followed for 12.7±4.6 years. Risk of diabetes developing was 24% greater for women in the highest dietary energy density quintile compared with the lowest after adjusting for confounders (95% CI 1.17 to 1.32). Body mass index (calculated as kg/m2) and waist circumference mediated the relationship between dietary energy density and diabetes. In waist circumference-stratified analysis, women in dietary energy density quintiles 2 to 5 with waist circumferences >88 cm were at 9% to 12% greater risk of diabetes developing compared with women with waist circumference ≤88 cm.

CONCLUSIONS

In this prospective study, a higher baseline dietary energy density was associated with higher incidence of type 2 diabetes among postmenopausal women, both overall, and in women with elevated waist circumference.

Risk of Diabetes After Hysterectomy With or Without Oophorectomy in Postmenopausal Women

The aim of this study was to determine the associations between hysterectomy, bilateral salpingo-oophorectomy (BSO), and incidence of diabetes in postmenopausal women participating in the Women's Health Initiative (WHI), a series of trials conducted in the United States, during the period 1993-1998. A total of 67,130 postmenopausal women aged 50-79 years were followed for a mean of 13.4 years. Among them, 7,430 cases of diabetes were diagnosed. Multivariable Cox proportional hazards models were used to assess the association between hysterectomy/oophorectomy status and diabetes incidence. Compared with women without hysterectomy, women with hysterectomy had a significantly higher risk of diabetes (hazard ratio = 1.13, 95% confidence interval: 1.06, 1.21). The increased risk of diabetes was similar for women with hysterectomy only and for women with hysterectomy with concomitant BSO. Compared with hysterectomy alone, hysterectomy with BSO was not associated with additional risk of diabetes after stratification by age at hysterectomy and hormone therapy status. In our large, prospective study, we observed that hysterectomy, regardless of oophorectomy status, was associated with increased risk of diabetes among postmenopausal women. However, our data did not support the hypothesis that early loss of ovarian estrogens is a risk factor for type 2 diabetes. The modest increased risk of diabetes associated with hysterectomy may be due to residual confounding, such as the reasons for hysterectomy.

Dietary Inflammatory Index, Bone Mineral Density, and Risk of Fracture in Postmenopausal Women: Results From the Women's Health Initiative

Previous studies suggest that bone loss and fracture risk are associated with higher inflammatory milieu, potentially modifiable by diet. The primary objective of this analysis was to evaluate the association of the dietary inflammatory index (DII), a measure of the inflammatory potential of diet, with risk of hip, lower-arm, and total fracture using longitudinal data from the Women's Health Initiative Observational Study and Clinical Trials. Secondarily, we evaluated changes in bone mineral density (BMD) and DII scores. DII scores were calculated from baseline food frequency questionnaires (FFQs) completed by 160,191 participants (mean age 63 years) without history of hip fracture at enrollment. Year 3 FFQs were used to calculate a DII change score. Fractures were reported at least annually; hip fractures were confirmed by medical records. Hazard ratios for fractures were computed using multivariable-adjusted Cox proportional hazard models, further stratified by age and race/ethnicity. Pairwise comparisons of changes in hip BMD, measured by dual-energy X-ray absorptiometry from baseline, year 3, and year 6 were analyzed by quartile (Q1 = least inflammatory diet) of baseline DII scores in a subgroup of women (n = 10,290). Mean DII score improved significantly over 3 years (p < 0.01), but change was not associated with fracture risk. Baseline DII score was only associated with hip fracture risk in younger white women (HR Q4,1.48; 95% CI, 1.09 to 2.01; p = 0.01). There were no significant associations among white women older than 63 years or other races/ethnicities. Women with the least inflammatory DII scores had less loss of hip BMD (p = 0.01) by year 6, despite lower baseline hip BMD, versus women with the most inflammatory DII scores. In conclusion, a less inflammatory dietary pattern was associated with less BMD loss in postmenopausal women. A more inflammatory diet was associated with increased hip fracture risk only in white women younger than 63 years. © 2016 American Society for Bone and Mineral Research.

Intentional Weight Loss and Endometrial Cancer Risk

Purpose Although obesity is an established endometrial cancer risk factor, information about the influence of weight loss on endometrial cancer risk in postmenopausal women is limited. Therefore, we evaluated associations among weight change by intentionality with endometrial cancer in the Women's Health Initiative (WHI) observational study. Patients and Methods Postmenopausal women (N = 36,794) ages 50 to 79 years at WHI enrollment had their body weights measured and body mass indices calculated at baseline and at year 3. Weight change during that period was categorized as follows: stable (change within ± 5%), loss (change ≥ 5%), and gain (change ≥ 5%). Weight loss intentionality was assessed via self-report at year 3; change was characterized as intentional or unintentional. During the subsequent 11.4 years (mean) of follow-up, 566 incident endometrial cancer occurrences were confirmed by medical record review. Multivariable Cox proportional hazards regression models were used to evaluate relationships (hazard ratios [HRs] and 95% CIs) between weight change and endometrial cancer incidence. Results In multivariable analyses, compared with women who had stable weight (± 5%), women with weight loss had a significantly lower endometrial cancer risk (HR, 0.71; 95% CI, 0.54 to 0.95). The association was strongest among obese women with intentional weight loss (HR, 0.44; 95% CI, 0.25 to 0.78). Weight gain (≥ 10 pounds) was associated with a higher endometrial cancer risk than was stable weight, especially among women who had never used hormones. Conclusion Intentional weight loss in postmenopausal women is associated with a lower endometrial cancer risk, especially among women with obesity. These findings should motivate programs for weight loss in obese postmenopausal women.

Projecting Individualized Absolute Invasive Breast Cancer Risk in US Hispanic Women

Background

There is no model to estimate absolute invasive breast cancer risk for Hispanic women.

Methods

The San Francisco Bay Area Breast Cancer Study (SFBCS) provided data on Hispanic breast cancer case patients (533 US-born, 553 foreign-born) and control participants (464 US-born, 947 foreign-born). These data yielded estimates of relative risk (RR) and attributable risk (AR) separately for US-born and foreign-born women. Nativity-specific absolute risks were estimated by combining RR and AR information with nativity-specific invasive breast cancer incidence and competing mortality rates from the California Cancer Registry and Surveillance, Epidemiology, and End Results program to develop the Hispanic risk model (HRM). In independent data, we assessed model calibration through observed/expected (O/E) ratios, and we estimated discriminatory accuracy with the area under the receiver operating characteristic curve (AUC) statistic.

Results

The US-born HRM included age at first full-term pregnancy, biopsy for benign breast disease, and family history of breast cancer; the foreign-born HRM also included age at menarche. The HRM estimated lower risks than the National Cancer Institute's Breast Cancer Risk Assessment Tool (BCRAT) for US-born Hispanic women, but higher risks in foreign-born women. In independent data from the Women's Health Initiative, the HRM was well calibrated for US-born women (observed/expected [O/E] ratio = 1.07, 95% confidence interval [CI] = 0.81 to 1.40), but seemed to overestimate risk in foreign-born women (O/E ratio = 0.66, 95% CI = 0.41 to 1.07). The AUC was 0.564 (95% CI = 0.485 to 0.644) for US-born and 0.625 (95% CI = 0.487 to 0.764) for foreign-born women.

Conclusions

The HRM is the first absolute risk model that is based entirely on data specific to Hispanic women by nativity. Further studies in Hispanic women are warranted to evaluate its validity.

Longitudinal changes in the dietary inflammatory index: an assessment of the inflammatory potential of diet over time in postmenopausal women

BACKGROUND/OBJECTIVES

The dietary inflammatory index (DII) measured at one time point is associated with risk of several chronic diseases, but disease risk may change with longitudinal changes in DII scores. Data are lacking regarding changes in DII scores over time; therefore, we assessed changes in the DII in the Women's Health Initiative (WHI).

SUBJECTS/METHODS

DII scores were calculated using data from repeated food frequency questionnaires in the WHI Observational Study (OS; n=76 671) at baseline and year 3, and the WHI Dietary Modification trial (DM; n=48482) at three time points. Lower DII scores represent more anti-inflammatory diets. We used generalized estimating equations to compare mean changes in DII over time, adjusting for multiple comparisons, and multivariable-adjusted linear regression analyses to determine predictors of DII change.

RESULTS

In the OS, mean DII decreased modestly from -1.14 at baseline to -1.50 at year 3. In the DM, DII was -1.32 in year 1, -1.60 in year 3 and -1.48 in year 6 in the intervention arm and was -0.65 in year 1, -0.94 in year 3 and -0.96 in year 6 in the control arm. These changes were modified by body mass index, education and race/ethnicity. A prediction model explained 22% of the variance in the change in DII scores in the OS.

CONCLUSIONS

In this prospective investigation of postmenopausal women, reported dietary inflammatory potential decreased modestly over time. Largest reductions were observed in normal-weight, highly educated women. Future research is warranted to examine whether reductions in DII are associated with decreased chronic disease risk.

Hysterectomy, Oophorectomy, and Risk of Thyroid Cancer

CONTEXT

Estrogen has been suggested as a risk factor for thyroid cancer.

OBJECTIVE

The aim of this study is to examine the associations between hysterectomy, bilateral salpingo-oophorectomy (BSO), and incidence of thyroid cancer.

DESIGN

This was a prospective cohort study.

SETTING

The study was conducted at 40 clinical centers in the United States.

PARTICIPANTS

A total of 127 566 women aged 50-79 were enrolled in the Women's Health Initiative during 1993-1998.

MAIN OUTCOME MEASURES

Hysterectomy and BSO were self-reported. Incident thyroid cancer cases were confirmed by medical record review.

RESULTS

Three hundred forty-four incident thyroid cancer cases were identified during an average of 14.4 years of follow-up. Compared with women without hysterectomy, women with hysterectomy, regardless of ovarian status, had a significantly higher risk of thyroid cancer (hazard ratio 1.46 [95% confidence interval 1.16-1.85]). Hysterectomy with BSO was not associated with a lower risk for thyroid cancer compared with hysterectomy alone. Among women with hysterectomy alone, hormone therapy use was associated with lower risk of thyroid cancer (hazard ratio 0.47 [95% confidence interval 0.28-0.78]). However, we did not observe significant associations between hormone therapy use and thyroid cancer in women without hysterectomy or women with hysterectomy plus BSO.

CONCLUSION

Our large prospective study observed that hysterectomy, regardless of oophorectomy status, was associated with increased risk of thyroid cancer among postmenopausal women. In addition, our data did not support the hypotheses that exogenous estrogen is a risk factor or that estrogen deprivation is a protective factor for thyroid cancer. Further research is needed to clarify whether these apparent associations may be due to shared risk factors between indications for hysterectomy and thyroid cancer.

Patterns of change over time and history of the inflammatory potential of diet and risk of breast cancer among postmenopausal women

We utilized the dietary inflammatory index (DII) to investigate associations between patterns of change in, and history of the inflammatory potential of diet and risk of breast cancer in the Women's Health Initiative (WHI). We included 70,998 postmenopausal women aged 50-79 years recruited from 1993 to 1998 into the WHI Observational Study and Dietary Modification trial control group and followed through August 29, 2014. We utilized data from food frequency questionnaires administered at baseline and Year 3, to calculate average DII scores, patterns of change in DII, and used these measures in multivariable-adjusted Cox regression models to estimate hazards ratios (HR) and 95 % confidence intervals (CI) for incident invasive breast cancer and its subtypes. After 1,093,947 person-years of follow-up, 3471 cases of invasive breast cancer were identified. There was no substantial association between average DII scores or patterns of change in DII and risk of overall invasive breast cancer (HR, 1.03; 95 % CI, 0.90, 1.17; P-trend = 0.79; comparing extreme average DII quintiles). However, there was a significant nonlinear association between average DII scores and the ER-, PR-, HER2+, subtype (HR, 2.37; 95 % CI, 1.08, 5.20; P-trend = 0.18; comparing extreme quintiles). For patterns of change in DII, the age-adjusted association with ER-, PR-, HER2+ subtype comparing women in the proinflammatory stable to those in the anti-inflammatory stable categories (HR, 1.82; 95 % CI, 1.06, 3.13) persisted in the multivariable-adjusted model but was less precise (HR, 1.85; 95 % CI, 0.96, 3.55; P = 0.06). Dietary inflammatory potential may differentially influence the development of specific breast cancer phenotypes.

A Randomized Trial of a Low-Fat Diet Intervention on Blood Pressure and Hypertension: Tertiary Analysis of the WHI Dietary Modification Trial

BACKGROUND

This post hoc analysis determined if the Women's Health Initiative (WHI) Diet Modification intervention (DM-I) resulted in a significantly different rate of incident hypertension (HTN), as well as longitudinal changes in blood pressure.

METHODS

Participants were 48,835 postmenopausal women aged 50-79 years who were randomly assigned to either the intervention or comparison group. HTN was defined as self-report of treated HTN collected semiannually or blood pressure ≥140/90mm Hg at one of the annual follow-up clinic visits.

RESULTS

After a mean follow-up of 8.3 years, and among those who did not have HTN at baseline (n = 31,146), there were 16,174 (51.9%) HTN cases and those assigned to the intervention group had a 4% lower overall risk of developing incident HTN (hazard ratio (HR): 0.96, 95% confidence interval (CI): 0.93-0.99). Although the risk of HTN was lower in the DM-I group in the first few years, the HR became greater than 1 after year 5 (P-trend < 0.01). Similarly, randomization to the DM-I arm resulted in a small but significantly lower average systolic blood pressure (SBP) at 1 year of follow-up (-0.66mm Hg, 0.44-0.89) that increased over the following 8 years (0.16mm Hg/year, 0.11-0.21), such that any early benefit was eliminated by year 5 and a minimal deleterious effect emerged by year 7.

CONCLUSION

Randomization to an intensive behavioral dietary modification program aimed at a lower total fat intake is not associated with sustained reductions in blood pressure or risk of HTN in postmenopausal women.

CLINICAL TRIAL REGISTRATION

url http://www.clinicaltrials.gov, unique identifier nct00000611.

Pre-existing diabetes and lung cancer prognosis

BACKGROUND

The aims of this study are to investigate the impact of pre-existing diabetes and diabetes treatments on lung cancer prognosis.

METHODS

A total of 2484 women with confirmed incident lung cancer from the Women's Health Initiative were followed for an average of 2.9 years through the date of death or 29 August 2014.

RESULTS

Compared with women with lung cancer but without diabetes, women with lung cancer and diabetes had significantly increased risk of overall mortality (HR=1.27, 95% CI: 1.07-1.50). Women with diabetes receiving insulin or metformin or women who had long duration of diabetes also had increased risk of overall mortality.

CONCLUSIONS

Our large prospective study provides evidence that pre-existing diabetes is associated with poor overall survival among women with lung cancer, but do not support the hypothesis that metformin use may have a protective effect in women with lung cancer and diabetes.

Tubal Ligation and Risk of Endometrial Cancer: Findings From the Women's Health Initiative

OBJECTIVE

Bilateral tubal ligation (BTL) is a common form of birth control in the United States. There are limited, contradictory data examining BTL and the risk of endometrial cancer and none examining type I and type II cancers separately. We investigated the association between BTL and endometrial cancer risk using the Women's Health Initiative (WHI) Observational and Dietary Modification Studies.

METHODS

Demographic information and history of BTL were obtained from the baseline questionnaires from 76,483 WHI participants in the Observational and Dietary Modification Studies. Univariable and multivariable models were used to examine the association of BTL with type I and type II endometrial cancers.

RESULTS

A total of 1137 women were diagnosed with incident endometrial cancer (972 type I and 128 type II) during a mean follow-up of 11.3 years. Overall, 14,499 (19%) women had undergone BTL. There were no statistically significant associations noted between BTL and age at BTL for type I or type II cancers.

CONCLUSIONS

We examined the largest patient cohort to date in an effort to determine the impact of BTL on endometrial cancer risk. In the WHI trial, we observed no overall effect of BTL on the risk of type I or type II endometrial cancer, suggesting that patients undergoing this popular birth control method likely do not have an associated change in their baseline risk for endometrial cancer.

Correlates of Successful Aging in Racial and Ethnic Minority Women Age 80 Years and Older: Findings from the Women's Health Initiative

BACKGROUND

Most research has focused on definitions and predictors of successful aging. However, racial/ethnic minorities are often under represented in this research. Given that the U.S. population is aging and becoming more racially diverse, we examined correlates of "successful aging," as defined by physical functioning and overall quality of life (QOL), among racial/ethnic minority women aged 80 years and older in the Women's Health Initiative.

METHODS

Participants included 1,924 racial/ethnic minority women (African Americans, Asian/Pacific Islanders, Hispanic/Latinos, and American Indian/Alaskan Natives) 80 years of age and older who are enrolled in the Women's Health Initiative and have physical functioning data after turning 80 years of age. Analysis of covariance was used to examine between and within group differences in physical functioning and selfrated overall QOL for African Americans, Asian/Pacific Islanders, and Hispanic/Latinos.

RESULTS

We found no significant differences in physical functioning between racial/ethnic minority groups in adjusted analyses. However, overall QOL was significantly different between racial/ethnic minority groups. Age, recreational physical activity, and overall selfrated health were independent correlates of physical functioning across racial/ethnic minority groups, whereas overall selfrated health was the only consistent correlate of overall QOL across the minority groups for the within minority group comparisons.

CONCLUSIONS

Between racial/ethnic minority group differences in physical functioning are largely explained by demographic, psychosocial, behavioral, and health-related variables. We found statistically significant differences in selfrated overall QOL between racial/ethnic minority groups.

Diabetes, Diabetes Treatment, and Risk of Thyroid Cancer

OBJECTIVE

The objective of this study was to assess the relationships among diabetes, diabetes treatment and thyroid cancer risk using a large prospective cohort, the Women's Health Initiative.

METHODS

A total of 147 934 women who were free of known cancer at baseline were followed prospectively. Diabetes status and diabetes treatment at baseline and during follow-up were ascertained. Incident cases of thyroid cancers were confirmed by physician review of central medical records and pathology reports. Time-dependent Cox proportional hazards regressions were used to estimate hazard ratios and 95% confidence intervals for thyroid cancer risk associated with diabetes status, diabetes treatment, and duration of diabetes.

RESULTS

With a median follow-up time of 15.9 years, 391 incident thyroid cancers were identified. We found no significant associations between thyroid cancer and diabetes (hazard ratio = 1.09; 95% confidence interval, 0.79-1.52), diabetes treatment, or duration of diabetes.

CONCLUSION

Our findings do not support the hypothesis that diabetes, or treatment of diabetes is associated with risk of thyroid cancer among postmenopausal women. Studies to investigate the specific effects of hyperinsulinemia and insulin resistance on thyroid cancer risk may provide additional information.

The impact of multimorbidity on quality of life among midlife women: findings from a U.S. nationally representative survey

BACKGROUND

Little is known about the prevalence and cumulative burden of coexisting health conditions including chronic joint and muscular pain, urinary incontinence (UI), depression, osteoporosis risk, moderate/severe vasomotor symptoms, and vulvar/vaginal atrophy (VVA). We surveyed a nationally representative U.S. sample of midlife (age 40-64 years) women to ascertain the prevalence, general health-related quality of life (HRQoL), and health-seeking behaviors associated with these six conditions.

METHODS

This cross-sectional, telephone survey collected data from a sample of English- and Spanish-speaking U.S. women. The survey contained demographic and menopausal status questions, and also five condition-specific symptom/disease risk-screening instruments. The EuroQol 5 dimensions (EQ-5D) questionnaire was used to measure HRQoL. Health-seeking behavior was measured based on clinician discussion of and recent treatment for each condition.

RESULTS

Three thousand fifty eight women (mean age 53.4 years) completed the survey. The majority were white (75.6%), married (60.5%), employed full- or part-time (59.0%), and postmenopausal (69.8%; based on self-report). The prevalence [95% confidence interval] of 0, 1, 2, and ≥3 conditions was 35.2% [33.5-36.9], 34.2% [32.5-35.9], 17.9% [16.6-19.3], and 12.7% [11.5-13.9], respectively. Osteoporosis risk (30.6%) was most prevalent, followed by VVA (27.8%) and UI (26.6%). UI and VVA coexisted most frequently (11.3%), followed by osteoporosis risk and VVA (9.8%). EQ-5D scores decreased with increasing number of illnesses (0, 1, 2, and ≥3 conditions, means: 0.92, 0.87, 0.77, 0.61, respectively; p<0.01). Health-seeking behavior varied by condition.

CONCLUSION

Over 25% of women surveyed had multiple coexisting conditions. Lower HRQoL was associated with multiple conditions and with each added condition.

Low-Fat Dietary Pattern Intervention and Health-Related Quality of Life: The Women's Health Initiative Randomized Controlled Dietary Modification Trial

BACKGROUND

Intensive dietary intervention programs may lead to benefits in vitality and other components of health quality. The Women's Health Initiative Dietary Modification (DM) intervention includes a large randomized controlled trial of an intensive intervention.

OBJECTIVE

To evaluate whether the intervention is associated with improved health-related quality of life (HRQoL) subscales, overall self-reported health, depression symptoms, cognitive functioning, and sleep quality.

DESIGN

This randomized controlled trial was analyzed as intent to treat.

PARTICIPANTS

Between 1993 and 1998, 48,835 women aged 50 to 79 years were recruited by 40 clinical centers across the United States. Eligibility included having fat intake at baseline ≥32% of total calories, and excluded women with any prior colorectal or breast cancer, recent other cancers, type 1 diabetes, or medical conditions with predicted survival <3 years.

INTERVENTION

Goals were to reduce calories from fat to 20%, increase vegetables and fruit to 5+ servings, and increase grain servings to 6+ servings a day. During the first year, 18 group sessions were held, with quarterly sessions thereafter.

MAIN OUTCOME MEASURES

The RAND 36-Item Health Survey was used to assess HRQoL at baseline, Year 1, and close-out (about 8 years postrandomization), and estimate differential HRQoL subscale change scores.

STATISTICAL ANALYSES PERFORMED

Mean change in HRQoL scores (Year 1 minus baseline) were compared by randomization group using linear models.

RESULTS

At 1 year, there was a differential change between intervention and comparison group of 1.7 units (95% CI 1.5, 2.0) in general health associated with the intervention. DM intervention improved physical functioning by 2.0 units (95% CI 1.7, 2.3), vitality by 1.9 units (95% CI 1.6, 2.2), and global quality of life by 0.09 units (95% CI 0.07, 0.12). With the exception of global quality of life, these effects were significantly modified by body mass index at baseline.

CONCLUSIONS

DM intervention was associated with small, but significant improvements in three HRQoL subscales: general health, physical functioning, and vitality at 1 year follow-up, with the largest improvements seen in the women with the greatest baseline body mass index.

Fusion of clinical and stochastic finite element data for hip fracture risk prediction

Hip fracture affects more than 250,000 people in the US and 1.6 million worldwide per year. With an aging population, the development of reliable fracture risk models is therefore of prime importance. Due to the complexity of the hip fracture phenomenon, the use of clinical data only, as it is done traditionally, might not be sufficient to ensure an accurate and robust hip fracture prediction model. In order to increase the predictive ability of the risk model, the authors propose to supplement the clinical data with computational data from finite element models. The fusion of the two types of data is performed using deterministic and stochastic computational data. In the latter case, uncertainties in loading and material properties of the femur are accounted for and propagated through the finite element model. The predictive capability of a support vector machine (SVM) risk model constructed by combining clinical and finite element data was assessed using a Women׳s Health Initiative (WHI) dataset. The dataset includes common factors such as age and BMD as well as geometric factors obtained from DXA imaging. The fusion of computational and clinical data systematically leads to an increase in predictive ability of the SVM risk model as measured by the AUC metric. It is concluded that the largest gains in AUC are obtained by the stochastic approach. This gain decreases as the dimensionality of the problem increases: a 5.3% AUC improvement was achieved for a 9 dimensional problem involving geometric factors and weight while a 1.3% increase was obtained for a 20 dimensional case including geometric and conventional factors.

In utero exposure of rats to high-fat diets perturbs gene expression profiles and cancer susceptibility of prepubertal mammary glands

Human studies suggest that high-fat diets (HFDs) increase the risk of breast cancer. The 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary carcinogenesis rat model is commonly used to evaluate the effects of lifestyle factors such as HFD on mammary tumor risk. Past studies focused primarily on the effects of continuous maternal exposure on the risk of offspring at the end of puberty (PND50). We assessed the effects of prenatal HFD exposure on cancer susceptibility in prepubertal mammary glands and identified key gene networks associated with such disruption. During pregnancy, dams were fed AIN-93G-based diets with isocaloric high olive oil, butterfat or safflower oil. The control group received AIN-93G. Female offspring were treated with DMBA on PND21. However, a significant increase in tumor volume and a trend of shortened tumor latency were observed in rats with HFD exposure against the controls (P=.048 and P=.067, respectively). Large-volume tumors harbored carcinoma in situ. Transcriptome profiling identified 43 differentially expressed genes in the mammary glands of the HFBUTTER group as compared with control. Rapid hormone signaling was the most dysregulated pathway. The diet also induced aberrant expression of Dnmt3a, Mbd1 and Mbd3, consistent with potential epigenetic disruption. Collectively, these findings provide the first evidence supporting susceptibility of prepubertal mammary glands to DMBA-induced tumorigenesis that can be modulated by dietary fat that involves aberrant gene expression and likely epigenetic dysregulation.

Newly Developed Chronic Conditions and Changes in Health-Related Quality of Life in Postmenopausal Women

OBJECTIVES

To prospectively assess the effects of newly developed chronic conditions on changes in health-related quality of life (HRQoL) in postmenopausal women.

DESIGN

Prospective cohort study.

SETTING

Forty clinical centers in the United States.

PARTICIPANTS

Women aged 50 to 79 enrolled in the Women's Health Initiative Observational Study during 1993-98 (N = 75,198).

MEASUREMENTS

Onset of seven chronic conditions (hypertension, heart disease, stroke, cancer, osteoporosis, diabetes mellitus, arthritis), HRQoL based on the Medical Outcomes Study 36-item Short Form survey (SF-36), and change in HRQoL from baseline to Year 3 in scores on the Physical (PCS) and Mental (MCS) Component Summary of the SF-36.

RESULTS

Each of the seven chronic conditions was statistically significantly associated with HRQoL for physical and mental health. Women with incident stroke had the greatest decline in HRQoL for physical and mental health (PCS: 10.2, 95% confidence interval (CI) = 8.3-12.1;

MCS

10.4, 95% CI = 8.8-12.1), which exceeded minimal clinically important differences (MCID). Having more new chronic conditions was associated with greater decrease in HRQoL. Declines in HRQoL in women with two or more chronic conditions exceeded MCID. Those with heart disease and stroke had the largest decline in physical health, and those with stroke and arthritis had the greatest decline in mental health. For all conditions other than stroke and diabetes mellitus, the more recently a condition was diagnosed, the greater the decrease in PCS. For stroke and cancer, a similar pattern was observed for MCS.

CONCLUSION

The more conditions a woman developed, the greater reduction in HRQoL she experienced. Declines in HRQoL in women with stroke, cancer, and some combinations exceeded MCID. Findings from this study might lead to more-effective patient-centered approaches to health care for women with multiple chronic conditions.

Marginal structural models for the estimation of the risk of Diabetes Mellitus in the presence of elevated depressive symptoms and antidepressant medication use in the Women's Health Initiative observational and clinical trial cohorts

BACKGROUND

We evaluate the combined effect of the presence of elevated depressive symptoms and antidepressant medication use with respect to risk of type 2 diabetes among approximately 120,000 women enrolled in the Women's Health Initiative (WHI), and compare several different statistical models appropriate for causal inference in non-randomized settings.

METHODS

Data were analyzed for 52,326 women in the Women's Health Initiative Clinical Trials (CT) Cohort and 68,169 women in the Observational Study (OS) Cohort after exclusions. We included follow-up to 2005, resulting in a median duration of 7.6 years of follow up after enrollment. Results from three multivariable Cox models were compared to those from marginal structural models that included time varying measures of antidepressant medication use, presence of elevated depressive symptoms and BMI, while adjusting for potential confounders including age, ethnicity, education, minutes of recreational physical activity per week, total energy intake, hormone therapy use, family history of diabetes and smoking status.

RESULTS

Our results are consistent with previous studies examining the relationship of antidepressant medication use and risk of type 2 diabetes. All models showed a significant increase in diabetes risk for those taking antidepressants. The Cox Proportional Hazards models using baseline covariates showed the lowest increase in risk , with hazard ratios of 1.19 (95 % CI 1.06 - 1.35) and 1.14 (95 % CI 1.01 - 1.30) in the OS and CT, respectively. Hazard ratios from marginal structural models comparing antidepressant users to non-users were 1.35 (95 % CI 1.21 - 1.51) and 1.27 (95 % CI 1.13 - 1.43) in the WHI OS and CT, respectively - however, differences among estimates from traditional Cox models and marginal structural models were not statistically significant in both cohorts. One explanation suggests that time-dependent confounding was not a substantial factor in these data, however other explanations exist. Unadjusted Cox Proportional Hazards models showed that women with elevated depressive symptoms had a significant increase in diabetes risk that remained after adjustment for confounders. However, this association missed the threshold for statistical significance in propensity score adjusted and marginal structural models.

CONCLUSIONS

Results from the multiple approaches provide further evidence of an increase in risk of type 2 diabetes for those on antidepressants.

Factors Associated with Nursing Home Admission after Stroke in Older Women

BACKGROUND

We examined the social and economic factors associated with nursing home (NH) admission in older women, overall and poststroke.

METHODS

The Women's Health Initiative (WHI) included women aged 50-79 years at enrollment (1993-1998). In the WHI Extension Study (2005-2010), participants annually reported any NH admission in the preceding year. Separate multivariate logistic regression models analyzed social and economic factors associated with long-term NH admission, defined as an admission on 2 or more questionnaires, overall and poststroke.

RESULTS

Of 103,237 participants, 8904 (8.6%) reported NH admission (2005-2010); 534 of 2225 (24.0%) women with incident stroke reported poststroke NH admission. Decreased likelihoods of NH admission overall were demonstrated for Asian, Black, and Hispanic women (versus whites, adjusted odds ratio [aOR] = .35-.44, P < .001) and women with higher income (aOR = .75, 95% confidence interval [CI] = .63-.90), whereas increased likelihoods of NH admission overall were seen for women with lower social support (aOR = 1.34, 95% CI = 1.16-1.54) and with incident stroke (aOR = 2.59, 95% CI = 2.15-3.12). Increased odds of NH admission after stroke were demonstrated for women with moderate disability after stroke (aOR = 2.76, 95% CI = 1.73-4.42). Further adjustment for stroke severity eliminated the association found for race/ethnicity, income, and social support.

CONCLUSIONS

The level of care needed after a disabling stroke may overwhelm social and economic structures in place that might otherwise enable avoidance of NH admission. We need to identify ways to provide care consistent with patients' preferences, even after a disabling stroke.

Effects of total fat intake on body weight

BACKGROUND

In order to prevent overweight and obesity in the general population we need to understand the relationship between the proportion of energy from fat and resulting weight and body fatness in the general population.

OBJECTIVES

To assess the effects of proportion of energy intake from fat on measures of weight and body fatness (including obesity, waist circumference and body mass index) in people not aiming to lose weight, using all appropriate randomised controlled trials (RCTs) and cohort studies in adults, children and young people

SEARCH METHODS

We searched CENTRAL to March 2014 and MEDLINE, EMBASE and CINAHL to November 2014. We did not limit the search by language. We also checked the references of relevant reviews.

SELECTION CRITERIA

Trials fulfilled the following criteria: 1) randomised intervention trial, 2) included children (aged ≥ 24 months), young people or adults, 3) randomised to a lower fat versus usual or moderate fat diet, without the intention to reduce weight in any participants, 4) not multifactorial and 5) assessed a measure of weight or body fatness after at least six months. We also included cohort studies in children, young people and adults that assessed the proportion of energy from fat at baseline and assessed the relationship with body weight or fatness after at least one year. We duplicated inclusion decisions and resolved disagreement by discussion or referral to a third party.

DATA COLLECTION AND ANALYSIS

We extracted data on the population, intervention, control and outcome measures in duplicate. We extracted measures of weight and body fatness independently in duplicate at all available time points. We performed random-effects meta-analyses, meta-regression, subgrouping, sensitivity and funnel plot analyses.

MAIN RESULTS

We included 32 RCTs (approximately 54,000 participants) and 30 sets of analyses of 25 cohorts. There is consistent evidence from RCTs in adults of a small weight-reducing effect of eating a smaller proportion of energy from fat; this was seen in almost all included studies and was highly resistant to sensitivity analyses. The effect of eating less fat (compared with usual diet) is a mean weight reduction of 1.5 kg (95% confidence interval (CI) -2.0 to -1.1 kg), but greater weight loss results from greater fat reductions. The size of the effect on weight does not alter over time and is mirrored by reductions in body mass index (BMI) (-0.5 kg/m(2), 95% CI -0.7 to -0.3) and waist circumference (-0.3 cm, 95% CI -0.6 to -0.02). Included cohort studies in children and adults most often do not suggest any relationship between total fat intake and later measures of weight, body fatness or change in body fatness. However, there was a suggestion that lower fat intake was associated with smaller increases in weight in middle-aged but not elderly adults, and in change in BMI in the highest validity child cohort.

AUTHORS' CONCLUSIONS

Trials where participants were randomised to a lower fat intake versus usual or moderate fat intake, but with no intention to reduce weight, showed a consistent, stable but small effect of low fat intake on body fatness: slightly lower weight, BMI and waist circumference compared with controls. Greater fat reduction and lower baseline fat intake were both associated with greater reductions in weight. This effect of reducing total fat was not consistently reflected in cohort studies assessing the relationship between total fat intake and later measures of body fatness or change in body fatness in studies of children, young people or adults.

Calcium and vitamin D supplementation do not influence menopause-related symptoms: Results of the Women's Health Initiative Trial

BACKGROUND

It is unknown whether supplementation with calcium and vitamin D has an impact on menopause-related symptoms.

METHODS

As part of the Women's Health Initiative Calcium/Vitamin D Supplementation Trial (CaD), women were randomized at 40 clinical sites to elemental calcium carbonate 1000 mg with vitamin D 400 IU daily or placebo. At the CaD baseline visit (year 1 or year 2) and during a mean follow-up of 5.7 years, participants provided data on menopause-related symptoms via questionnaires. Generalized linear mixed effects techniques were used to address research questions.

RESULTS

After excluding participants with missing data (N=2125), we compared menopause-related symptoms at follow-up visits of 17,101 women randomized to CaD with those of 17,056 women given the placebo. Women in the CaD arm did not have a different number of symptoms at follow-up compared to women taking the placebo (p=0.702). Similarly, there was no difference between sleep disturbance, emotional well-being, or energy/fatigue at follow-up in those who were randomized to CaD supplementation compared to those taking the placebo.

CONCLUSIONS

Our data suggest that supplementation with 1000 mg of calcium plus 400 IU of vitamin D does not influence menopause-related symptoms over an average of 5.7 years of follow-up among postmenopausal women with an average age of 64 at the WHI baseline visit.

Reduction in saturated fat intake for cardiovascular disease

BACKGROUND

Reducing saturated fat reduces serum cholesterol, but effects on other intermediate outcomes may be less clear. Additionally it is unclear whether the energy from saturated fats that are lost in the diet are more helpfully replaced by polyunsaturated fats, monounsaturated fats, carbohydrate or protein. This review is part of a series split from and updating an overarching review.

OBJECTIVES

To assess the effect of reducing saturated fat intake and replacing it with carbohydrate (CHO), polyunsaturated (PUFA) or monounsaturated fat (MUFA) and/or protein on mortality and cardiovascular morbidity, using all available randomised clinical trials.

SEARCH METHODS

We updated our searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid) and EMBASE (Ovid) on 5 March 2014. We also checked references of included studies and reviews.

SELECTION CRITERIA

Trials fulfilled the following criteria: 1) randomised with appropriate control group; 2) intention to reduce saturated fat intake OR intention to alter dietary fats and achieving a reduction in saturated fat; 3) not multifactorial; 4) adult humans with or without cardiovascular disease (but not acutely ill, pregnant or breastfeeding); 5) intervention at least 24 months; 6) mortality or cardiovascular morbidity data available.

DATA COLLECTION AND ANALYSIS

Two review authors working independently extracted participant numbers experiencing health outcomes in each arm, and we performed random-effects meta-analyses, meta-regression, subgrouping, sensitivity analyses and funnel plots.

MAIN RESULTS

We include 15 randomised controlled trials (RCTs) (17 comparisons, ˜59,000 participants), which used a variety of interventions from providing all food to advice on how to reduce saturated fat. The included long-term trials suggested that reducing dietary saturated fat reduced the risk of cardiovascular events by 17% (risk ratio (RR) 0.83; 95% confidence interval (CI) 0.72 to 0.96, 13 comparisons, 53,300 participants of whom 8% had a cardiovascular event, I² 65%, GRADE moderate quality of evidence), but effects on all-cause mortality (RR 0.97; 95% CI 0.90 to 1.05; 12 trials, 55,858 participants) and cardiovascular mortality (RR 0.95; 95% CI 0.80 to 1.12, 12 trials, 53,421 participants) were less clear (both GRADE moderate quality of evidence). There was some evidence that reducing saturated fats reduced the risk of myocardial infarction (fatal and non-fatal, RR 0.90; 95% CI 0.80 to 1.01; 11 trials, 53,167 participants), but evidence for non-fatal myocardial infarction (RR 0.95; 95% CI 0.80 to 1.13; 9 trials, 52,834 participants) was unclear and there were no clear effects on stroke (any stroke, RR 1.00; 95% CI 0.89 to 1.12; 8 trials, 50,952 participants). These relationships did not alter with sensitivity analysis. Subgrouping suggested that the reduction in cardiovascular events was seen in studies that primarily replaced saturated fat calories with polyunsaturated fat, and no effects were seen in studies replacing saturated fat with carbohydrate or protein, but effects in studies replacing with monounsaturated fats were unclear (as we located only one small trial). Subgrouping and meta-regression suggested that the degree of reduction in cardiovascular events was related to the degree of reduction of serum total cholesterol, and there were suggestions of greater protection with greater saturated fat reduction or greater increase in polyunsaturated and monounsaturated fats. There was no evidence of harmful effects of reducing saturated fat intakes on cancer mortality, cancer diagnoses or blood pressure, while there was some evidence of improvements in weight and BMI.

AUTHORS' CONCLUSIONS

The findings of this updated review are suggestive of a small but potentially important reduction in cardiovascular risk on reduction of saturated fat intake. Replacing the energy from saturated fat with polyunsaturated fat appears to be a useful strategy, and replacement with carbohydrate appears less useful, but effects of replacement with monounsaturated fat were unclear due to inclusion of only one small trial. This effect did not appear to alter by study duration, sex or baseline level of cardiovascular risk. Lifestyle advice to all those at risk of cardiovascular disease and to lower risk population groups should continue to include permanent reduction of dietary saturated fat and partial replacement by unsaturated fats. The ideal type of unsaturated fat is unclear.

Insulin Resistance and Risk of Cardiovascular Disease in Postmenopausal Women

Background—

Insulin resistance is associated with diabetes mellitus, but it is uncertain whether it improves cardiovascular disease (CVD) risk prediction beyond traditional cardiovascular risk factors.

Methods and Results—

We identified 15 288 women from the Women’s Health Initiative Biomarkers studies with no history of CVD, atrial fibrillation, or diabetes mellitus at baseline (1993–1998). We assessed the prognostic value of adding fasting serum insulin, HOMA-IR (homeostasis model assessment–insulin resistance), serum-triglyceride-to-serum-high-density lipoprotein-cholesterol ratio TG/HDL-C, or impaired fasting glucose (serum glucose ≥110 mg/dL) to traditional risk factors in separate Cox multivariable analyses and assessed risk discrimination and reclassification. The study end point was major CVD events (nonfatal and fatal coronary heart disease and ischemic stroke) within 10 years, which occurred in 894 (5.8%) women. Insulin resistance was associated with CVD risk after adjusting for age and race/ethnicity with hazard ratios (95% confidence interval [CI]) per doubling in insulin of 1.21 (CI, 1.12–1.31), in HOMA-IR of 1.19 (CI, 1.11–1.28), in TG/HDL-C of 1.35 (CI, 1.26–1.45), and for impaired fasting glucose of 1.31 (CI, 1.05–1.64). Although insulin, HOMA-IR, and TG/HDL-C remained associated with increased CVD risk after adjusting for most CVD risk factors, none remained significant after adjusting for HDL-C: hazard ratios for insulin, 1.06 (CI, 0.98–1.16); for HOMA-IR, 1.06 (CI, 0.98–1.15); for TG/HDL-C, 1.11 (CI, 0.99–1.25); and for glucose, 1.20 (CI, 0.96–1.50). Insulin resistance measures did not improve CVD risk discrimination and reclassification.

Conclusions—

Measures of insulin resistance were no longer associated with CVD risk after adjustment for high-density lipoprotein-cholesterol and did not provide independent prognostic information in postmenopausal women without diabetes mellitus.

Clinical Trial Registration Information—

URL: http://www.clinicaltrial.gov . Unique identifier: NCT00000611.

The Evolution of the WHI 80+ Cohort

BACKGROUND

The Women's Health Initiative has collected data on the aging process of postmenopausal women for over two decades, including data on many women who have achieved age 80 years and older. However, there has not been any previous effort to characterize the 80+ cohort and to identify associated retention factors.

METHODS

We include all women at baseline of the Women's Health Initiative who would be at least 80 years of age as of September 17, 2012. We summarize retention rates during the study and across two re-enrollment campaigns as well as the demographic and health-related characteristics that predicted retention. Further, we describe the longitudinal change from baseline in the women identified as members of the 80+ cohort.

RESULTS

Retention rates were lower during each of two re-enrollment periods (74% and 83% retained during re-enrollment periods 1 and 2, respectively) than during the first and second data collection periods (90% each). Women who were retained were more likely to be white, educated, and healthier at baseline. Women age 80 and older saw modest changes in body mass index and depression burden, despite lower physical activity and increased cardiovascular disease.

CONCLUSIONS

The characteristics of women who were retained in the 80+ cohort differ in significant ways compared with their peers at baseline. Identifying the characteristics associated with attrition in older cohorts is important because aging and worsening health has a negative impact on study attrition. Strategies should be implemented to improve retention rates among less healthy older adults.

Long-chain ω-3 fatty acid intake and endometrial cancer risk in the Women's Health Initiative

BACKGROUND

Inflammation may be important in endometrial cancer development. Long-chain ω-3 (n-3) polyunsaturated fatty acids (LCω-3PUFAs) may reduce inflammation and, therefore, reduce cancer risk. Because body mass is associated with both inflammation and endometrial cancer risk, it may modify the association of fat intake on risk.

OBJECTIVE

We examined whether intakes of LCω-3PUFAs were associated with endometrial cancer risk overall and stratified by body size and histologic subtype.

DESIGN

Women were n = 87,360 participants of the Women's Health Initiative Observational Study and Clinical Trials who were aged 50-79 y, had an intact uterus, and completed a baseline food-frequency questionnaire. After 13 y of follow-up, n = 1253 incident invasive endometrial cancers were identified. Cox regression models were used to estimate HRs and 95% CIs for the association of intakes of individual ω-3 fatty acids and fish with endometrial cancer risk.

RESULTS

Intakes of individual LCω-3PUFAs were associated with 15-23% linear reductions in endometrial cancer risk. In women with body mass index (BMI; in kg/m(2)) <25, those in the upper compared with lowest quintiles of total LCω-3PUFA intake (sum of eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) had significantly reduced endometrial cancer risk (HR: 0.59; 95% CI: 0.40, 0.82; P-trend = 0.001), whereas there was little evidence of an association in overweight or obese women. The reduction in risk observed in normal-weight women was further specific to type I cancers.

CONCLUSIONS

Long-chain ω-3 intake was associated with reduced endometrial cancer risk only in normal-weight women. Additional studies that use biomarkers of ω-3 intake are needed to more accurately estimate their effects on endometrial cancer risk. This trial was registered at clinicaltrials.gov as NCT00000611.

Cancer incidence and mortality during the intervention and postintervention periods of the Women's Health Initiative dietary modification trial

BACKGROUND

The Women's Health Initiative (WHI) low-fat (20% kcal) dietary modification (DM) trial (1993-2005) demonstrated a nonsignificant reduction in breast cancer, a nominally significant reduction in ovarian cancer, and no effect on other cancers (mean 8.3 years intervention). Consent to nonintervention follow-up was 83% (n = 37,858). This analysis was designed to assess postintervention cancer risk in women randomized to the low-fat diet (40%) versus usual diet comparison (60%).

METHODS

Randomized, controlled low-fat diet intervention for prevention of breast and colorectal cancers conducted in 48,835 postmenopausal U.S. women, ages 50 to 79 years at 40 U.S. sites. Outcomes included total invasive cancer, breast cancer, and colorectal cancer, and cancer-specific and overall mortality.

RESULTS

There were no intervention effects on invasive breast or colorectal cancer, other cancers, or cancer-specific or overall mortality during the postintervention period or the combined intervention and follow-up periods. For invasive breast cancer, the hazard ratios (HR) and 95% confidence interval (CI) were 0.92 (0.84-1.01) during intervention, 1.08 (0.94-1.24) during the postintervention period, and 0.97 (0.89-1.05) during cumulative follow-up. A reduced risk for estrogen receptor positive/progesterone receptor-negative tumors was demonstrated during follow-up. In women with higher baseline fat intake (quartile), point estimates of breast cancer risk were HR, 0.76 (95% CI, 0.62-0.92) during intervention versus HR, 1.11 (95% CI, 0.84-1.4) during postintervention follow-up (Pdiff = 0.03).

CONCLUSIONS

Dietary fat intake increased postintervention in intervention women; no long-term reduction in cancer risk or mortality was shown in the WHI DM trial.

IMPACT

Dietary advisement to reduce fat for cancer prevention after menopause generally was not supported by the WHI DM trial.

Vitamin D levels and menopause-related symptoms

OBJECTIVE

This study aims to determine whether vitamin D levels are associated with menopause-related symptoms in older women.

METHODS

A randomly selected subset of 1,407 women, among 26,104 potentially eligible participants of the Women's Health Initiative Calcium and Vitamin D trial of postmenopausal women aged 51 to 80 years, had 25-hydroxyvitamin D [25(OH)D] levels measured at the Women's Health Initiative Calcium and Vitamin D trial baseline visit. Information about menopause-related symptoms at baseline was obtained by questionnaire and included overall number of symptoms and composite measures of sleep disturbance, emotional well-being, and energy/fatigue, as well as individual symptoms. After exclusions for missing data, 530 women (mean [SD] age, 66.2 [6.8] y) were included in these analyses.

RESULTS

Borderline significant associations between 25(OH)D levels and total number of menopausal symptoms were observed (with P values ranging from 0.05 to 0.06 for fully adjusted models); however, the effect was clinically insignificant and disappeared with correction for multiple testing. No associations between 25(OH)D levels and composite measures of sleep disturbance, emotional well-being, or energy/fatigue were observed (P's > 0.10 for fully adjusted models).

CONCLUSIONS

There is no evidence for a clinically important association between serum 25(OH)D levels and menopause-related symptoms in postmenopausal women.

Non-steroidal anti-inflammatory drugs and cancer risk in women: results from the Women's Health Initiative

The use of non-steroidal anti-inflammatory drugs (NSAIDs) has been associated with reduced risks of cancers at several sites in some studies; however, we recently reported no association between their use and total cancer risk in women in a prospective study. Here we examine the association between NSAIDs and total and site-specific cancer incidence in the large, prospective Women's Health Initiative (WHI). Women (129,013) were recruited to participate in the WHI at 40 US clinical centers from 1993 to 1998 and followed prospectively. After 9.7 years of follow-up, 12,998 incident, first primary, invasive cancers were diagnosed. NSAID use was systematically collected at study visits. We used Cox proportional hazards regression models to estimate multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for associations between NSAIDs use and total and site-specific cancer risk. Relative to non-use, consistent use (i.e., use at baseline and year 3 of follow-up) of any NSAID was not associated with total cancer risk (HR 1.00, 95% CI: 0.94-1.06). Results for individual NSAIDs were similar to the aggregate measure. In site-specific analyses, NSAIDs were associated with reduced risks of colorectal cancer, ovarian cancer, and melanoma. Our study confirms a chemopreventive benefit for colorectal cancer in women and gives preliminary evidence for a reduction of the risk of some rarer cancers. NSAIDs' benefit on cancer risk was therefore limited to specific sites and not evident when total cancer risk was examined. This information may be of importance when NSAIDs are considered as chemopreventive agents.

Association between diabetes, diabetes treatment and risk of developing endometrial cancer

Background:

A growing body of evidence suggests that diabetes is a risk factor for endometrial cancer incidence. However, most of these studies used case-control study designs and did not adjust for obesity, an established risk factor for endometrial cancer. In addition, few epidemiological studies have examined the association between diabetes treatment and endometrial cancer risk. The objective of this study was to assess the relationships among diabetes, diabetes treatment and endometrial cancer risk in postmenopausal women participating in the Women's Health Initiative (WHI).

Methods:

A total of 88 107 postmenopausal women aged 50–79 years who were free of cancer and had no hysterectomy at baseline were followed until date of endometrial cancer diagnosis, death, hysterectomy or loss to follow-up, whichever came first. Endometrial cancers were confirmed by central medical record and pathology report review. Multivariate Cox proportional hazards regression models were used to estimate hazard ratios (HRs) (95% confidence interval (CI)) for diagnosis of diabetes and metformin treatment as risk factors for endometrial cancer.

Results:

Over a mean of 11 years of follow-up, 1241 endometrial cancers developed. In the primary analysis that focused on prevalent diabetes at enrolment, compared with women without diabetes, women with self-reported diabetes, and the subset of women with treated diabetes, had significantly higher risk of endometrial cancer without adjusting for BMI (HR=1.44, 95% CI: 1.13–1.85 for diabetes, HR=1.57, 95% CI: 1.19–2.07 for treated diabetes). However after adjusting for BMI, the associations between diabetes, diabetes treatment, diabetes duration and the risk of endometrial cancer became non-significant. Elevated risk was noted when considering combining diabetes diagnosed at baseline and during follow-up as time-dependent exposure (HR=1.31, 95% CI: 1.08–1.59) even after adjusting for BMI. No significant association was observed between metformin use and endometrial cancer risk.

Conclusions:

Our results suggest that the relationship observed in previous research between diabetes and endometrial cancer incidence may be largely confounded by body weight, although some modest independent elevated risk remains.

Optimism and diet quality in the Women's Health Initiative

Diet quality has not been well studied in relation to positive psychological traits. Our purpose was to investigate the relationship between optimism and diet quality in postmenopausal women enrolled in the Women's Health Initiative observational study (OS) and clinical trials (CTs), and to determine whether optimism was associated with diet change after a 1-year dietary intervention. Diet quality was scored with the Alternate Healthy Eating Index (AHEI) and optimism assessed with the Life Orientation Test-Revised. Baseline characteristics were compared across AHEI quintiles or optimism tertiles using regression models with each variable of interest as a function of quintiles or tertiles (OS, n=87,630; CT, n=65,360). Association between optimism and baseline AHEI and change in AHEI over 1 year were tested using multivariate linear regression (CT, n=13,645). Potential interaction between optimism and trial arm and demographic/lifestyle factors on AHEI change was tested using likelihood ratio test (CT intervention, n=13,645; CT control, n=20,242). Women reporting high AHEI were non-Hispanic white, educated, physically active, past or never smokers, hormone therapy users, had lower body mass index and waist circumference, and were less likely to have chronic conditions. In the CT intervention, higher optimism was associated with higher AHEI at baseline and with greater change over 1 year (P=0.001). Effect modification by intervention status was observed (P=0.014), whereas control participants with highest optimism achieved threefold greater AHEI increase compared with those with the lowest optimism. These data support a relationship between optimism and dietary quality score in postmenopausal women at baseline and over 1 year.

Effect of dietary modification on incident carotid artery disease in postmenopausal women: results from the women's health initiative dietary modification trial

BACKGROUND AND PURPOSE

Because the diagnosis and treatment of carotid artery disease may reduce the rate of stroke, the aim of this study was to determine whether a diet intervention was associated with incident carotid artery disease.

METHODS

Participants were 48 835 postmenopausal women aged 50 to 79 years who were randomly assigned to either the intervention or comparison group in the Women's Health Initiative Diet Modification Trial. Incident carotid artery disease was defined as an overnight hospitalization with either symptoms or a surgical intervention to improve flow.

RESULTS

After a mean follow-up of 8.3 years from 1994 to 2005, there were 297 (0.61%) incident carotid artery events. In contrast to the comparison group, the risk of incident carotid disease did not differ from those assigned to the intervention group (hazard ratio, 1.08; 95% confidence interval, 0.9-1.4). In secondary analysis, there was no significant effect of the intervention on the risk for incident carotid disease during the 5 years of postintervention follow-up from 2005 to 2010 (hazard ratio, 1.24; 95% confidence interval, 0.9-1.7) and no significant effect during cumulative follow-up from 1994 to 2010 (hazard ratio, 1.13; 95% confidence interval, 0.9-1.4).

CONCLUSIONS

Among postmenopausal women, a dietary intervention aimed at reducing total fat intake and encouraging increased intake of fruit, vegetables, and grains did not significantly change the risk for incident carotid artery disease.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00000611.

An exploratory study of respiratory quotient calibration and association with postmenopausal breast cancer

BACKGROUND

The respiratory quotient (RQ), defined as the ratio of carbon dioxide exhaled to oxygen uptake, reflects substrate utilization when energy is expended. Fat and alcohol have RQ values of approximately 0.7, compared with 1.0 for carbohydrate, and approximately 0.8 for protein. Here, the association between RQ and postmenopausal breast cancer risk is studied.

METHODS

Paired RQ measurements were obtained, separated by approximately 6 months, for women in the reliability subset of a Women's Health Initiative (WHI) Nutrition and Physical Activity Assessment Study. Linear regression of the average of the paired log RQ assessments on a corresponding log food quotient (FQ) average and other study subject characteristics, including age, body mass index, race, and education, yielded calibration equations for predicting RQ.

RESULTS

Calibration equations, using any of food frequency, food record, or dietary recall data, explained an appreciable fraction of measured log RQ variation, and these were used to compute calibrated RQ estimates throughout WHI cohorts. Calibrated RQ estimates using 4-day food record (4DFR) data related inversely (P = 0.004) to (invasive) breast cancer risk in the WHI Dietary Modification trial comparison group, and corresponding RQ estimates using food-frequency data related inversely (P = 0.002) to breast cancer incidence in this cohort combined with the larger WHI observational study.

CONCLUSION

Although preliminary, these analyses suggest a substantially higher postmenopausal breast cancer risk among women having relatively low RQ.

IMPACT

RQ elevation could provide a novel target for breast cancer risk reduction.

All-cause, cardiovascular, and cancer mortality rates in postmenopausal white, black, Hispanic, and Asian women with and without diabetes in the United States: the Women's Health Initiative, 1993-2009

Using data from the Women's Health Initiative (1993-2009; n = 158,833 participants, of whom 84.1% were white, 9.2% were black, 4.1% were Hispanic, and 2.6% were Asian), we compared all-cause, cardiovascular, and cancer mortality rates in white, black, Hispanic, and Asian postmenopausal women with and without diabetes. Cox proportional hazard models were used for the comparison from which hazard ratios and 95% confidence intervals were computed. Within each racial/ethnic subgroup, women with diabetes had an approximately 2-3 times higher risk of all-cause, cardiovascular, and cancer mortality than did those without diabetes. However, the hazard ratios for mortality outcomes were not significantly different between racial/ethnic subgroups. Population attributable risk percentages (PARPs) take into account both the prevalence of diabetes and hazard ratios. For all-cause mortality, whites had the lowest PARP (11.1, 95% confidence interval (CI): 10.1, 12.1), followed by Asians (12.9, 95% CI: 4.7, 20.9), blacks (19.4, 95% CI: 15.0, 23.7), and Hispanics (23.2, 95% CI: 14.8, 31.2). To our knowledge, the present study is the first to show that hazard ratios for mortality outcomes were not significantly different between racial/ethnic subgroups when stratified by diabetes status. Because of the "amplifying" effect of diabetes prevalence, efforts to reduce racial/ethnic disparities in the rate of death from diabetes should focus on prevention of diabetes.

Smoking and diabetes: does the increased risk ever go away?

Recent studies reported that smoking cessation leads to higher short-term risk of type 2 diabetes than continuing to smoke. However, the duration of increased diabetes risk following smoking cessation needs further investigation. We followed 135,906 postmenopausal women aged 50-79 years enrolled in the Women's Health Initiative between September 1, 1993, and December 31, 1998, over an average of 11 years to examine the association between smoking cessation and risk of diabetes using Cox proportional hazard multivariable-adjusted regression models. Compared with that for never smokers, the risk for diabetes was significantly elevated in current smokers (hazard ratio = 1.28, 95% confidence interval: 1.20, 1.36) but was even higher in women who quit smoking during the first 3 years of follow-up (hazard ratio = 1.43, 95% confidence interval: 1.26, 1.63). Among former smokers, the risk of diabetes decreased significantly as the time since quitting increased and was equal to that of never smokers following a cessation period of 10 years. In new quitters with low cumulative exposure (<20 pack-years), diabetes risk was not elevated following smoking cessation. In conclusion, the risk of diabetes in former smokers returns to that in never smokers 10 years after quitting, and even more quickly in lighter smokers.

Prestroke factors associated with poststroke mortality and recovery in older women in the Women's Health Initiative

OBJECTIVES

To examine prestroke lifestyle factors associated with poststroke mortality and recovery in older women.

DESIGN

Longitudinal prospective cohort study.

SETTING

The Women's Health Initiative (WHI, clinical trials and observational study), 40 clinical centers in the United States.

PARTICIPANTS

WHI participants, women aged 50 to 79, who were stroke-free at baseline (1993/98), with incident stroke before 2005.

MEASUREMENTS

Participants were followed for mortality through 2010. Prestroke characteristics were from the last examination before the stroke event. Annual follow-up for clinical events ascertained hospitalization for stroke that was subsequently physician adjudicated with medical records. Multivariable regression models were used to analyze factors associated with poststroke mortality and poststroke recovery at hospital discharge (poststroke Glasgow score), adjusting for stroke type.

RESULTS

Of 3,173 women with incident stroke, 1,111 (35%) died. Individuals who were overweight or obese before stroke had lower poststroke mortality than those who were normal weight (obese: hazard ratio (HR) = 0.69, 95% confidence interval (CI) = 0.53-0.88; overweight: HR = 0.72, 95% CI = 0.58-0.90); individuals who were underweight before stroke had nonsignificantly greater poststroke mortality (HR = 2.02, 95% CI = 0.98-4.16, P = .06). Other prestroke factors associated with poststroke mortality included diabetes mellitus (HR = 1.28, 95% CI = 1.01-1.64), current smoking (vs nonsmoker, HR = 2.13, 95% CI = 1.53-3.00), physical inactivity (vs >150 min of exercise per week, HR = 1.39, 95% CI = 1.09-1.78), and lowest physical function quartile (vs highest, HR = 1.54, 95% CI = 1.18-2.02). Prestroke diabetes mellitus was associated with lower odds of good recovery after stroke (odds ratio (OR) = 0.60, 95% CI = 0.44-0.82). Current hormone use before stroke was associated with greater odds of moderate than of severe disability after stroke (OR = 1.29, 95% CI = 1.00-1.66).

CONCLUSION

Potentially modifiable factors before stroke, including smoking, diabetes mellitus, and being underweight, were associated with greater poststroke mortality in older women. Being overweight or obese and physical activity before stroke were associated with lower poststroke mortality in older women.

Relations of depressive symptoms and antidepressant use to body mass index and selected biomarkers for diabetes and cardiovascular disease

OBJECTIVES

We investigated whether depressive symptoms and antidepressant use are associated with biomarkers for glucose dysregulation and inflammation, body mass index (BMI), and waist circumference.

METHODS

Postmenopausal women were recruited into the Women's Health Initiative from 1993 to 1998, and data were collected at regular intervals through 2005. We used multiple linear regression models to examine whether depressive symptoms and antidepressant use are associated with BMI, waist circumference, and biomarkers.

RESULTS

Analysis of data from 71, 809 women who completed all relevant baseline and year 3 assessments showed that both elevated depressive symptoms and antidepressant use were significantly associated with higher BMI and waist circumference. Among 1950 women, elevated depressive symptoms were significantly associated with increased insulin levels and measures of insulin resistance. Analyses of baseline data from 2242 women showed that both elevated depressive symptoms and antidepressant use were associated with higher C-reactive protein levels.

CONCLUSIONS

Monitoring body habitus and other biomarkers among women with elevated depression symptoms or taking antidepressant medication may be prudent to prevent diabetes and cardiovascular disease.