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2.
Biometrics ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021738

RESUMO

The identification of valid surrogate markers of disease or disease progression has the potential to decrease the length and costs of future studies. Most available methods that assess the value of a surrogate marker ignore the fact that surrogates are often measured with error. Failing to adjust for measurement error can erroneously identify a useful surrogate marker as not useful or vice versa. We investigate and propose robust methods to correct for the effect of measurement error when evaluating a surrogate marker using multiple estimators developed for parametric and nonparametric estimates of the proportion of treatment effect explained by the surrogate marker. In addition, we quantify the attenuation bias induced by measurement error and develop inference procedures to allow for variance and confidence interval estimation. Through a simulation study, we show that our proposed estimators correct for measurement error in the surrogate marker and that our inference procedures perform well in finite samples. We illustrate these methods by examining a potential surrogate marker that is measured with error, hemoglobin A1c, using data from the Diabetes Prevention Program clinical trial.

3.
Am J Epidemiol ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33025002

RESUMO

The health benefits and risks of menopausal hormone therapy among women aged 50-59 years are examined in the Women's Health Initiative randomized, placebo-controlled trials using long-term follow-up data and a parsimonious statistical model that leverages data from older participants to increase precision. These trials enrolled 27,347 healthy post-menopausal women aged 50-79 at 40 U.S. clinical centers during 1993-1998, including 10,739 post-hysterectomy participants in a trial of conjugated equine estrogens, and 16,608 participants with uterus in the trial of these estrogens plus medroxyprogesterone acetate. Over an 18-year (median) follow-up period (1993-2016) risk for a global index, defined as the earliest of coronary heart disease, invasive breast cancer, stroke, pulmonary embolism, colorectal cancer, endometrial cancer, hip fracture, and all-cause mortality, is reduced with conjugated equine estrogens with hazard ratio (95% confidence interval) of 0.82 (0.71, 0.95), and with nominally significant reductions for coronary heart disease, breast cancer, hip fracture and all-cause mortality. Corresponding global index hazard ratio estimates of 1.06 (0.95, 1.19) were non-significant for combined estrogens plus progestin, but increased breast cancer risk and reduced endometrial cancer risk were observed. These results, among women 50-59, substantially agree with the worldwide observational literature, with the exception of breast cancer for estrogens alone.

4.
J Nutr ; 150(10): 2764-2771, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32712658

RESUMO

BACKGROUND: The carbon isotope ratio (CIR) is a proposed biomarker for added sugar (AS) intake in the United States; however, because the CIR is also associated with meat intake in most populations the need for specificity remains. The CIR of amino acids (AAs) has the potential to differentiate sugars from meat intakes, because essential AAs must derive from dietary protein whereas certain nonessential AAs can be synthesized from sugars. OBJECTIVES: We tested whether serum CIR-AAs in combination with participant characteristics could meet a prespecified biomarker criterion for AS intake in the Nutrition and Physical Activity Assessment Study Feeding Study (NPAAS-FS) of the Women's Health Initiative, a population in which the whole-serum CIR was not associated with AS intake. METHODS: Postmenopausal women (n = 145) from Seattle, WA, were provided with individualized diets that approximated their habitual food intakes for 2 wk. Dietary intakes from consumed foods were characterized over the feeding period using the Nutrition Data System for Research. The CIR of 7 AAs-Ala, Gly, Val, Leu, Ile, Pro, and Phe-were measured in fasting serum collected at the end of the 2-wk feeding period, using gas chromatography-combustion isotope ratio mass spectrometry. Biomarker models were evaluated using regression R2 ≥ 0.36 as a major biomarker criterion, based on the benchmark R2 values of well-established recovery biomarkers in the NPAAS-FS. RESULTS: AS intake was associated with CIR-Ala (ρ = 0.32; P < 0.0001). A model of AS intake based on CIR-Ala, CIR-Gly, CIR-Ile, smoking, leisure physical activity, and body weight met the biomarker criterion (R2 = 0.37). Biomarker-estimated AS intake was not associated with meat or animal protein intake. CONCLUSIONS: Results support serum CIR-AAs in combination with participant characteristics as potential biomarkers of AS intake in US populations, including those with low AS intake.The Women's Health Initiative is registered at clinicaltrials.gov (NCT00000611).

5.
JAMA ; 324(4): 369-380, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32721007

RESUMO

Importance: The influence of menopausal hormone therapy on breast cancer remains unsettled with discordant findings from observational studies and randomized clinical trials. Objective: To assess the association of prior randomized use of estrogen plus progestin or prior randomized use of estrogen alone with breast cancer incidence and mortality in the Women's Health Initiative clinical trials. Design, Setting, and Participants: Long-term follow-up of 2 placebo-controlled randomized clinical trials that involved 27 347 postmenopausal women aged 50 through 79 years with no prior breast cancer and negative baseline screening mammogram. Women were enrolled at 40 US centers from 1993 to 1998 with follow-up through December 31, 2017. Interventions: In the trial involving 16 608 women with a uterus, 8506 were randomized to receive 0.625 mg/d of conjugated equine estrogen (CEE) plus 2.5 mg/d of medroxyprogesterone acetate (MPA) and 8102, placebo. In the trial involving 10 739 women with prior hysterectomy, 5310 were randomized to receive 0.625 mg/d of CEE alone and 5429, placebo. The CEE-plus-MPA trial was stopped in 2002 after 5.6 years' median intervention duration, and the CEE-only trial was stopped in 2004 after 7.2 years' median intervention duration. Main Outcomes and Measures: The primary outcome was breast cancer incidence (protocol prespecified primary monitoring outcome for harm) and secondary outcomes were deaths from breast cancer and deaths after breast cancer. Results: Among 27 347 postmenopausal women who were randomized in both trials (baseline mean [SD] age, 63.4 years [7.2 years]), after more than 20 years of median cumulative follow-up, mortality information was available for more than 98%. CEE alone compared with placebo among 10 739 women with a prior hysterectomy was associated with statistically significantly lower breast cancer incidence with 238 cases (annualized rate, 0.30%) vs 296 cases (annualized rate, 0.37%; hazard ratio [HR], 0.78; 95% CI, 0.65-0.93; P = .005) and was associated with statistically significantly lower breast cancer mortality with 30 deaths (annualized mortality rate, 0.031%) vs 46 deaths (annualized mortality rate, 0.046%; HR, 0.60; 95% CI, 0.37-0.97; P = .04). In contrast, CEE plus MPA compared with placebo among 16 608 women with a uterus was associated with statistically significantly higher breast cancer incidence with 584 cases (annualized rate, 0.45%) vs 447 cases (annualized rate, 0.36%; HR, 1.28; 95% CI, 1.13-1.45; P < .001) and no significant difference in breast cancer mortality with 71 deaths (annualized mortality rate, 0.045%) vs 53 deaths (annualized mortality rate, 0.035%; HR, 1.35; 95% CI, 0.94-1.95; P= .11). Conclusions and Relevance: In this long-term follow-up study of 2 randomized trials, prior randomized use of CEE alone, compared with placebo, among women who had a previous hysterectomy, was significantly associated with lower breast cancer incidence and lower breast cancer mortality, whereas prior randomized use of CEE plus MPA, compared with placebo, among women who had an intact uterus, was significantly associated with a higher breast cancer incidence but no significant difference in breast cancer mortality.


Assuntos
Neoplasias da Mama/epidemiologia , Estrogênios Conjugados (USP)/efeitos adversos , Terapia de Reposição Hormonal/efeitos adversos , Histerectomia , Acetato de Medroxiprogesterona/efeitos adversos , Idoso , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/mortalidade , Neoplasias da Mama/prevenção & controle , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Seguimentos , Humanos , Histerectomia/efeitos adversos , Incidência , Acetato de Medroxiprogesterona/uso terapêutico , Pessoa de Meia-Idade , Pós-Menopausa , Risco
6.
J Clin Oncol ; 38(26): 3071-3072, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32614701
7.
Am J Epidemiol ; 189(9): 972-981, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32314781

RESUMO

Dual-outcome intention-to-treat hazard rate analyses have potential to complement single-outcome analyses for the evaluation of treatments or exposures in relation to multivariate time-to-response outcomes. Here we consider pairs formed from important clinical outcomes to obtain further insight into influences of menopausal hormone therapy on chronic disease. As part of the Women's Health Initiative, randomized, placebo-controlled hormone therapy trials of conjugated equine estrogens (CEE) among posthysterectomy participants and of these same estrogens plus medroxyprogesterone acetate (MPA) among participants with an intact uterus were carried out at 40 US clinical centers (1993-2016). These data provide the context for analyses covering the trial intervention periods and a nearly 20-year (median) cumulative duration of follow-up. The rates of multiple outcome pairs were significantly influenced by hormone therapy, especially over cumulative follow-up, providing potential clinical and mechanistic insights. For example, among women randomized to either regimen, hazard ratios for pairs defined by fracture during intervention followed by death from any cause were reduced and hazard ratios for pairs defined by gallbladder disease followed by death were increased, though these findings may primarily reflect single-outcome associations. In comparison, hazard ratios for diabetes followed by death were reduced with CEE but not with CEE + MPA, and those for hypertension followed by death were increased with CEE + MPA but not with CEE.


Assuntos
Terapia de Reposição de Estrogênios , Ensaios Clínicos Controlados Aleatórios como Assunto , Idoso , Doenças Cardiovasculares/epidemiologia , Estrogênios Conjugados (USP)/administração & dosagem , Feminino , Fraturas Ósseas/epidemiologia , Doenças da Vesícula Biliar/epidemiologia , Humanos , Incidência , Análise de Intenção de Tratamento , Acetato de Medroxiprogesterona/administração & dosagem , Pessoa de Meia-Idade , Pós-Menopausa , Fatores de Risco , Estados Unidos/epidemiologia
9.
Curr Dev Nutr ; 4(3): nzaa021, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32159070

RESUMO

Background: Women without cardiovascular disease (CVD) or hypertension at baseline assigned to intervention in the Women's Health Initiative Dietary Modification (DM) trial experienced 30% lower risk of coronary heart disease (CHD), whereas results in women with hypertension or prior CVD could have been confounded by postrandomization use of statins. Objectives: Intervention participants reported various self-selected changes to achieve the 20% total fat goals. Reviewed are intervention compared with comparison group HRs for CHD, stroke, and total CVD in relation to specific dietary changes in normotensive participants. Methods: Dietary change was assessed by comparing baseline with year 1 FFQ data in women (n = 10,371) without hypertension or CVD at baseline with intake of total fat above the median to minimize biases due to use of the FFQ in trial eligibility screening. Results: Intervention participants self-reported compensating reduced energy intake from total fat by increasing carbohydrate and protein. Specifically they increased plant protein, with those in the upper quartile (increased total protein by ≥3.3% of energy) having a CHD HR of 0.39 (95% CI: 0.22, 0.71), compared with 0.92 (95% CI: 0.57, 1.48) for those in the lower quartile of change (decreased total protein ≥0.6% of energy), with P-trend of 0.04. CHD HR did not vary significantly with change in percentage energy from carbohydrate, and stroke HR did not vary significantly with any macronutrient changes. Scores reflecting adherence to recommended dietary patterns including the Dietary Approaches to Stop Hypertension Trial and the Healthy Eating Index showed favorable changes in the intervention group. Conclusions: Intervention group total fat reduction replaced with increased carbohydrate and some protein, especially plant-based protein, was related to lower CHD risk in normotensive women without CVD who reported high baseline total fat intake. This trial was registered at clinicaltrials.gov as NCT00000611. Link to the WHI trial protocol: https://www.whi.org/about/SitePages/Dietary%20Trial.aspx.

10.
Am J Clin Nutr ; 112(1): 168-179, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32133498

RESUMO

BACKGROUND: We recently presented associations between serum-based biomarkers of carotenoid and tocopherol intake and chronic disease risk in a Women's Health Initiative (WHI) Measurement Precision subcohort (n = 5488). Questions remain as to whether self-reported dietary data can usefully augment such biomarkers or can be calibrated using biomarkers for reliable disease association estimation in larger WHI cohorts. OBJECTIVES: The aims were to examine the potential of FFQ data to explain intake variation in a WHI Feeding Study and to compare association parameter estimates and their precision from studies based on biomarker-calibrated FFQ intake in larger WHI cohorts, with those previously presented. METHODS: Serum-based intake measures were augmented by using FFQ data in a WHI Feeding Study (n = 153). Corresponding calibration equations were generated, both in a companion Nutritional Biomarker Study (n = 436) and in the previously mentioned subcohort (n = 5488), by regressing these intake measures on dietary data and participant characteristics, for α- and ß-carotene, lutein plus zeaxanthin, and α-tocopherol. The supplemental value of FFQ data was considered by examining the fraction of feeding study intake variation explained by these regression models. Calibrated intake and disease association analyses were evaluated by comparisons with previously reported subcohort results. RESULTS: The inclusion of FFQ data led to some increases in feeding study intake variation explained (total R2 of ∼50%). Calibrated intake estimates explained 25-75% of serum-based intake variation, whether developed using either of the 2 cohort subsamples. Related disease associations for micronutrients were precisely estimated in larger WHI cohorts (n = 76,691) but were often closer to the null compared with previously reported associations. CONCLUSIONS: FFQ data may usefully augment blood concentrations in estimating the intake of carotenoids and tocopherols. Calibrated intake estimates using FFQ, dietary supplement, and participant characteristics only may require further justification to ensure reliable estimation of related disease associations.


Assuntos
Micronutrientes/sangue , Idoso , Biomarcadores/sangue , Carotenoides/sangue , Doença Crônica , Estudos de Coortes , Feminino , Humanos , Micronutrientes/metabolismo , Pessoa de Meia-Idade , Estado Nutricional , Saúde da Mulher , alfa-Tocoferol/sangue , beta Caroteno/sangue
11.
Cancer ; 126(13): 2956-2964, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32212335

RESUMO

After reports from the Women's Health Initiative randomized trial evaluating estrogen plus progestin, there was a sudden, substantial, and sustained decrease in all categories of menopausal hormone therapy, and the first reduction in age-adjusted breast cancer incidence in more than 20 years was seen in 2003-2004 among US women 50 years of age or older. Subsequent trends in breast cancer incidence have been described, but most reports have not focused on the postmenopausal age group or fully engaged the potential influence of reduced hormone therapy on breast cancer incidence trends by race/ethnicity. To address this gap, this commentary examines trends for annual age-adjusted breast cancer incidence over a 40-year period from 1975 to 2015 for white and black women on the basis of findings from the Surveillance, Epidemiology, and End Results 9 registries. Overall, the sharp decline in breast cancer incidence seen in 2003-2004 was followed in the subsequent decade by a continued low breast cancer incidence plateau in white women that has largely persisted. In contrast, a new discordance between breast cancer incidence trends in black and white women has emerged. In the 2005-2015 decade, a sustained increase in breast cancer incidence in black women has resulted in annual incidence rates comparable, for the first time, to those in white women. This commentary explores the hypothesis that the over-decade-long and discordant changes in breast cancer incidence rates in postmenopausal black and white women are, to a large extent, associated with changes in hormone therapy use in these 2 groups.

12.
J Clin Oncol ; 38(13): 1419-1428, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32031879

RESUMO

PURPOSE: Observational studies of dietary fat intake and breast cancer have reported inconsistent findings. This topic was addressed in additional analyses of the Women's Health Initiative (WHI) Dietary Modification (DM) clinical trial that evaluated a low-fat dietary pattern influence on breast cancer incidence. METHODS: In the WHI DM trial, 48,835 postmenopausal women, ages 50-79 years, with no prior breast cancer, and a dietary fat intake of ≥ 32% of energy were randomly assigned at 40 US centers to a usual diet comparison group (60%) or dietary intervention group (40%). The goals were to reduce fat intake to 20% of energy and increase vegetable, fruit, and grain intake. Breast cancers were confirmed after central medical record review and serial National Death Index linkages to enhance mortality findings. RESULTS: During 8.5 years of dietary intervention, breast cancer incidence and deaths as a result of breast cancer were nonsignificantly lower in the intervention group, while deaths after breast cancer were statistically significantly lower both during intervention and through a 16.1-year (median) follow-up. Now, after a long-term, cumulative 19.6-year (median) follow-up, the significant reduction in deaths after breast cancer persists (359 [0.12%] v 652 [0.14%] deaths; hazard ratio [HR], 0.85; 95% CI, 0.74 to 0.96; P = .01), and a statistically significant reduction in deaths as a result of breast cancer (breast cancer followed by death attributed to the breast cancer) emerged (132 [0.037%, annualized risk] v 251 [0.047%] deaths, respectively; HR, 0.79; 95% CI, 0.64 to 0.97; P = .02). CONCLUSION: Adoption of a low-fat dietary pattern associated with increased vegetable, fruit, and grain intake, demonstrably achievable by many, may reduce the risk of death as a result of breast cancer in postmenopausal women.

13.
EClinicalMedicine ; 18: 100240, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31938786

RESUMO

Background: Meta-analyses of observational studies associate adherence to several dietary patterns with cognitive health. However, limited evidence from full scale, randomized controlled trials precludes causal inference regarding dietary effects on cognitive function. Methods: The Women's Health Initiative (WHI) Dietary Modification (DM) randomized trial, in 48,835 postmenopausal women, included a subset of 1,606 WHI Memory Study (WHIMS) participants >= 65 years old, to assess low-fat dietary pattern influence on global cognitive function, evaluated with annual screening (Modified Mini-Mental State Examinations [3MSE]). Participants were randomized by a computerized, permuted block algorithm, stratified by age group and center, to a dietary intervention (40%) to reduce fat intake to 20% of energy and increase fruit, vegetable and grain intake or usual diet comparison groups (60%). The study outcome was possible cognition impairment (failed cognitive function screening) through the 8.5 year (median) dietary intervention. Those failing screening received a comprehensive, multi-phase cognitive function assessment to classify as: no cognitive impairment, mild cognitive impairment, or probable dementia. Exploratory analyses examined the composite endpoint of death after possible cognitive impairment through 18.7 years (median) follow-up. The WHI trials are registered at ClinicalTrials.gov:NCT00000611. Findings: Among the 1,606 WHIMS participants, the dietary intervention statistically significantly reduced the incidence of possible cognitive impairment (n = 126; hazard ratio [HR] 0.59 95% confidence interval [CI] 0.38-0. 91, P = 0.01) with HR for dietary influence on subsequent mild cognitive impairment of 0.65 (95% CI 0.35-1.19) and HR of 0.63 (95% CI 0.19-2.10) for probable dementia (PD). Through 18.7 years, deaths from all-causes after possible cognitive impairment were non-significantly lower in the dietary intervention group (0.56% vs 0.77%, HR 0.83 95% CI 0.35 to 2.00, P = 0.16). Interpretation: Adoption of a low-fat eating pattern, representing dietary moderation, significantly reduced risk of possible cognitive impairment in postmenopausal women. Funding: Several Institutes of the US National Institutes of Health.

15.
Int J Cancer ; 146(9): 2394-2405, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276202

RESUMO

Cell-mediated immune suppression may play an important role in lung carcinogenesis. We investigated the associations for circulating levels of tryptophan, kynurenine, kynurenine:tryptophan ratio (KTR), quinolinic acid (QA) and neopterin as markers of immune regulation and inflammation with lung cancer risk in 5,364 smoking-matched case-control pairs from 20 prospective cohorts included in the international Lung Cancer Cohort Consortium. All biomarkers were quantified by mass spectrometry-based methods in serum/plasma samples collected on average 6 years before lung cancer diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with individual biomarkers were calculated using conditional logistic regression with adjustment for circulating cotinine. Compared to the lowest quintile, the highest quintiles of kynurenine, KTR, QA and neopterin were associated with a 20-30% higher risk, and tryptophan with a 15% lower risk of lung cancer (all ptrend < 0.05). The strongest associations were seen for current smokers, where the adjusted ORs (95% CIs) of lung cancer for the highest quintile of KTR, QA and neopterin were 1.42 (1.15-1.75), 1.42 (1.14-1.76) and 1.45 (1.13-1.86), respectively. A stronger association was also seen for KTR and QA with risk of lung squamous cell carcinoma followed by adenocarcinoma, and for lung cancer diagnosed within the first 2 years after blood draw. This study demonstrated that components of the tryptophan-kynurenine pathway with immunomodulatory effects are associated with risk of lung cancer overall, especially for current smokers. Further research is needed to evaluate the role of these biomarkers in lung carcinogenesis and progression.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico , Biomarcadores Tumorais/sangue , Carcinoma de Células Grandes/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Inflamação/complicações , Neoplasias Pulmonares/diagnóstico , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Adenocarcinoma de Pulmão/sangue , Adenocarcinoma de Pulmão/etiologia , Adulto , Idoso , Carcinoma de Células Grandes/sangue , Carcinoma de Células Grandes/etiologia , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/etiologia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Inflamação/sangue , Inflamação/imunologia , Cinurenina/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Neopterina/sangue , Prognóstico , Estudos Prospectivos , Fatores de Risco , Carcinoma de Pequenas Células do Pulmão/sangue , Carcinoma de Pequenas Células do Pulmão/etiologia , Triptofano/sangue
16.
Ann Intern Med ; 171(6): 406-414, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31499528

RESUMO

Background: Whether health outcomes of menopausal estrogen therapy differ between women with and without bilateral salpingo-oophorectomy (BSO) is unknown. Objective: To examine estrogen therapy outcomes by BSO status, with additional stratification by 10-year age groups. Design: Subgroup analyses of the randomized Women's Health Initiative Estrogen-Alone Trial. (ClinicalTrials.gov: NCT00000611). Setting: 40 U.S. clinical centers. Participants: 9939 women aged 50 to 79 years with prior hysterectomy and known oophorectomy status. Intervention: Conjugated equine estrogens (CEE) (0.625 mg/d) or placebo for a median of 7.2 years. Measurements: Incidence of coronary heart disease and invasive breast cancer (the trial's 2 primary end points), all-cause mortality, and a "global index" (these end points plus stroke, pulmonary embolism, colorectal cancer, and hip fracture) during the intervention phase and 18-year cumulative follow-up. Results: The effects of CEE alone did not differ significantly according to BSO status. However, age modified the effect of CEE in women with prior BSO. During the intervention phase, CEE was significantly associated with a net adverse effect (hazard ratio for global index, 1.42 [95% CI, 1.09 to 1.86]) in older women (aged ≥70 years), but the global index was not elevated in younger women (P trend by age = 0.016). During cumulative follow-up, women aged 50 to 59 years with BSO had a treatment-associated reduction in all-cause mortality (hazard ratio, 0.68 [CI, 0.48 to 0.96]), whereas older women with BSO had no reduction (P trend by age = 0.034). There was no significant association between CEE and outcomes among women with conserved ovaries, regardless of age. Limitations: The timing of CEE in relation to BSO varied; several comparisons were made without adjustment for multiple testing. Conclusion: The effects of CEE did not differ by BSO status in the overall cohort, but some findings varied by age. Among women with prior BSO, in those aged 70 years or older, CEE led to adverse effects during the treatment period, whereas women randomly assigned to CEE before age 60 seemed to derive mortality benefit over the long term. Primary Funding Source: The WHI program is funded by the National Heart, Lung, and Blood Institute; National Institutes of Health; and U.S. Department of Health and Human Services. Wyeth Ayerst donated the study drugs.


Assuntos
Terapia de Reposição de Estrogênios/métodos , Estrogênios Conjugados (USP)/uso terapêutico , Ovariectomia , Fatores Etários , Idoso , Neoplasias da Mama/epidemiologia , Causas de Morte , Neoplasias Colorretais/epidemiologia , Doença das Coronárias/epidemiologia , Feminino , Seguimentos , Fraturas do Quadril/epidemiologia , Humanos , Incidência , Menopausa , Pessoa de Meia-Idade , Embolia Pulmonar/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Estados Unidos/epidemiologia
17.
J Nutr ; 149(9): 1565-1574, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31175807

RESUMO

BACKGROUND: The preferred macronutrient dietary composition, and the health consequences of dietary fat reduction specifically, have been debated for decades. Here we provide a comprehensive overview of long-term health outcomes in the Women's Health Initiative Dietary Modification (DM) trial. OBJECTIVE: The DM trial aimed to examine whether a low-fat dietary pattern would reduce the risk of invasive breast cancer, colorectal cancer, and, secondarily, coronary heart disease (CHD), with various other health outcomes also considered. METHODS: The DM trial is a randomized controlled trial conducted at 40 centers in the US, among 48,835 postmenopausal women aged 50-79 y with baseline intake of ≥32% energy from fat. Participants were randomly assigned to a low-fat dietary pattern intervention group or to a usual-diet comparison group, during 1993-1998. Intervention goals were to reduce fat intake from ∼35% to 20% of total energy, in conjunction with increasing vegetables and fruit to 5 servings/d and grains to 6 servings/d. RESULTS: Over an 8.5-y (median) intervention period, intervention and comparison group differences included lower fat by 8-10%, and higher carbohydrate by 8-10%, of total energy, in conjunction with higher consumption of vegetables, fruit, and grains. Time-to-outcome analyses did not show significant differences between intervention and comparison groups for invasive breast cancer, colorectal cancer, or CHD, either over the intervention period or over longer-term cumulative follow-up. Additional analyses showed significant intervention group benefits related to breast cancer, CHD, and diabetes, without adverse effects. Over a 19.6-y (median) follow-up period, HRs (95% CIs) were 0.84 (0.74, 0.96) for breast cancer followed by death, and 0.87 (0.77, 0.98) for diabetes requiring insulin. CONCLUSIONS: Reduction in dietary fat with corresponding increase in vegetables, fruit, and grains led to benefits related to breast cancer, CHD, and diabetes, without adverse effects, among healthy postmenopausal US women.This trial was registered at clinicaltrials.gov as NCT00000611.


Assuntos
Neoplasias da Mama/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Doença das Coronárias/prevenção & controle , Diabetes Mellitus/terapia , Dieta com Restrição de Gorduras , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Saúde da Mulher
18.
Am J Clin Nutr ; 109(4): 1189-1196, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30915444

RESUMO

BACKGROUND: Biomarkers provide potential to objectively measure the intake of nutrients and foods, and thereby to strengthen nutritional epidemiology association studies. However, there are only a few established intake biomarkers, mostly based on recovery of nutrients or their metabolites in urine. Blood concentration measures provide a potential biomarker source for many additional nutritional variables, but their use in disease-association studies requires further development. OBJECTIVE: The aim of this study was to apply recently proposed serum-based carotenoid and tocopherol intake biomarkers and to examine their association with the incidence of major cardiovascular diseases, cancers, and diabetes in a subset of Women's Health Initiative (WHI) cohorts. METHODS: Serum concentrations of α- and ß-carotene, lutein plus zeaxanthin (L + Z), and α-tocopherol were routinely measured at baseline in a subset of 5488 enrollees in WHI cohorts. Intake biomarkers for these 4 micronutrients, obtained by combining serum concentrations with participant characteristics, were recently proposed using a 153-woman feeding study within WHI. These biomarker equations are augmented here to include pertinent disease risk factors and are associated with subsequent chronic disease incidence in this WHI subset. RESULTS: HRs for a doubling of micronutrient intake differed only moderately from the null for the outcomes considered. However, somewhat lower risks of specific cardiovascular outcomes, breast cancer, and diabetes were associated with a higher intake of α- and ß-carotene, lower risk of diabetes was associated with higher L + Z intake, and elevated risks of certain cardiovascular outcomes were associated with a higher intake of α-tocopherol. These patterns remained following the exclusion of baseline users of dietary supplements. CONCLUSIONS: Concentration biomarkers can be calculated from blood specimens obtained in large epidemiologic cohorts and applied directly in disease-association analyses, without relying on self-reported dietary data. Observed associations between carotenoid and tocopherol biomarkers and chronic disease risk could be usefully evaluated further using stored serum specimens on the entire WHI cohort. This study was registered at www.clinicaltrials.gov as NCT00000611.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Carotenoides/sangue , Diabetes Mellitus/prevenção & controle , Neoplasias/prevenção & controle , Tocoferóis/sangue , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doença Crônica/prevenção & controle , Estudos de Coortes , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Suplementos Nutricionais/análise , Feminino , Humanos , Luteína/sangue , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/epidemiologia , Estado Nutricional , Fatores de Risco , Estados Unidos/epidemiologia , Zeaxantinas/sangue
19.
BMJ ; 364: k4981, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30606716

RESUMO

OBJECTIVES: To conduct a comprehensive analysis of prospectively measured circulating high sensitivity C reactive protein (hsCRP) concentration and risk of lung cancer overall, by smoking status (never, former, and current smokers), and histological sub-type. DESIGN: Nested case-control study. SETTING: 20 population based cohort studies in Asia, Europe, Australia, and the United States. PARTICIPANTS: 5299 patients with incident lung cancer, with individually incidence density matched controls. EXPOSURE: Circulating hsCRP concentrations in prediagnostic serum or plasma samples. MAIN OUTCOME MEASURE: Incident lung cancer diagnosis. RESULTS: A positive association between circulating hsCRP concentration and the risk of lung cancer for current (odds ratio associated with a doubling in hsCRP concentration 1.09, 95% confidence interval 1.05 to 1.13) and former smokers (1.09, 1.04 to 1.14) was observed, but not for never smokers (P<0.01 for interaction). This association was strong and consistent across all histological subtypes, except for adenocarcinoma, which was not strongly associated with hsCRP concentration regardless of smoking status (odds ratio for adenocarcinoma overall 0.97, 95% confidence interval 0.94 to 1.01). The association between circulating hsCRP concentration and the risk of lung cancer was strongest in the first two years of follow-up for former and current smokers. Including hsCRP concentration in a risk model, in addition to smoking based variables, did not improve risk discrimination overall, but slightly improved discrimination for cancers diagnosed in the first two years of follow-up. CONCLUSIONS: Former and current smokers with higher circulating hsCRP concentrations had a higher risk of lung cancer overall. Circulating hsCRP concentration was not associated with the risk of lung adenocarcinoma. Circulating hsCRP concentration could be a prediagnostic marker of lung cancer rather than a causal risk factor.


Assuntos
Proteína C-Reativa/metabolismo , Carcinoma de Células Grandes/sangue , Carcinoma de Células Pequenas/sangue , Carcinoma de Células Escamosas/sangue , Neoplasias Pulmonares/sangue , Fumar/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores Tumorais/sangue , Carcinoma de Células Grandes/epidemiologia , Carcinoma de Células Pequenas/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , Ex-Fumantes/estatística & dados numéricos , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , não Fumantes/estatística & dados numéricos , Razão de Chances , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade , Fumantes/estatística & dados numéricos , Fumar/epidemiologia , Adulto Jovem
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