Process evaluation of the Yéego! Program to increase healthy eating and gardening among American Indian elementary school children

BACKGROUND

American Indian children are at increased risk for obesity and diabetes. School-based health promotion interventions are one approach to promoting healthy behaviors to reduce this risk, yet few studies have described their implementation and fidelity. We conducted a qualitative process evaluation of the Yéego! Healthy Eating and Gardening Program, a school-based intervention to promote healthy eating among Navajo elementary school children. The intervention included a yearlong integrated curriculum, as well as the construction and maintenance of a school-based garden.

METHODS

Our process evaluation included fidelity checklists completed by program staff and qualitative interviews with program staff and classroom teachers after the intervention was implemented. We used content analysis to identify themes.

RESULTS

We identified several themes related to evidence of delivery adherence, program satisfaction, and lessons learned about delivery. Intervention staff followed similar procedures to prepare for and deliver lessons, but timing, teaching styles, and school-level factors also impacted overall implementation fidelity. Teachers and students had positive perceptions of the program, especially lessons that were highly visual, experiential, and connected to Navajo culture and the surrounding community. Teachers and program staff identified ways to enhance the usability of the curriculum by narrowing the scope, relating content to student experiences, and aligning content with school curriculum standards.

CONCLUSIONS

The program was implemented with moderately high fidelity across contexts. We identified areas where modifications could improve engagement, acceptability, efficacy, and sustainability of the program. Our results have implications for the evaluation and dissemination of school-based health interventions to promote healthy eating among children, especially in American Indian communities.

Associations between Genetic Variants and Blood Biomarkers of One-Carbon Metabolism in Postmenopausal Women from the Women's Health Initiative Observational Study

BACKGROUND

Genetic variation in one-carbon metabolism may affect nutrient concentrations and biological functions. However, data on genetic variants associated with blood biomarkers of one-carbon metabolism in US postmenopausal women are limited, and whether these associations were affected by the nationwide folic acid (FA) fortification program is unclear.

OBJECTIVES

We investigated associations between genetic variants and biomarkers of one-carbon metabolism using data from the Women's Health Initiative Observational Study.

METHODS

In 1573 non-Hispanic White (NHW) and 282 Black/African American, American Indian/Alaska Native, Asian/Pacific Islander, and Hispanic/Latino women aged 50-79 y, 288 nonsynonymous and tagging single-nucleotide variants (SNVs) were genotyped. RBC folate, plasma folate, pyridoxal-5'-phosphate (PLP), vitamin B-12, homocysteine, and cysteine concentrations were determined in 12-h fasting blood. Multivariable linear regression tested associations per variant allele and for an aggregated genetic risk score. Effect modifications before, during, and after nationwide FA fortification were examined.

RESULTS

After correction for multiple comparisons, among NHW women, 5,10-methylenetetrahydrofolate reductase (MTHFR) rs1801133 (677C→T) variant T was associated with lower plasma folate (-13.0%; 95% CI: -17.3%, -8.6%) and higher plasma homocysteine (3.5%; 95% CI: 1.7%, 5.3%) concentrations. Other associations for nonsynonymous SNVs included DNMT3A rs11695471 (T→A) with plasma PLP; EHMT2 rs535586 (G→A), TCN2 rs1131603 (L349S A→G), and TCN2 rs35838082 (R188W G→A) with plasma vitamin B-12; CBS rs2851391 (G→A) with plasma homocysteine; and MTHFD1 rs2236224 (G→A) and rs2236225 (R653Q G→A) with plasma cysteine. The influence of FA fortification on the associations was limited. Highest compared with lowest quartiles of aggregated genetic risk scores from SNVs in MTHFR and MTRR were associated with 14.8% to 18.9% lower RBC folate concentrations. Gene-biomarker associations were similar in women of other races/ethnicities.

CONCLUSIONS

Our findings on genetic variants associated with several one-carbon metabolism biomarkers may help elucidate mechanisms of maintaining B vitamin status in postmenopausal women.

Cooking for Health: a healthy food budgeting, purchasing, and cooking skills randomized controlled trial to improve diet among American Indians with type 2 diabetes

Background

The prevalence of poor diet quality and type 2 diabetes are exceedingly high in many rural American Indian (AI) communities. Because of limited resources and infrastructure in some communities, implementation of interventions to promote a healthy diet is challenging—which may exacerbate health disparities by region (urban/rural) and ethnicity (AIs/other populations). It is critical to adapt existing evidence-based healthy food budgeting, purchasing, and cooking programs to be relevant to underserved populations with a high burden of diabetes and related complications. The Cooking for Health Study will work in partnership with an AI community in South Dakota to develop a culturally-adapted 12-month distance-learning-based healthy food budgeting, purchasing, and cooking intervention to improve diet among AI adults with type 2 diabetes.

Methods

The study will enroll 165 AIs with physician-diagnosed type 2 diabetes who reside on the reservation. Participants will be randomized to an intervention or control arm. The intervention arm will receive a 12-month distance-learning curriculum adapted from Cooking Matters® that focuses on healthy food budgeting, purchasing, and cooking skills. In-person assessments at baseline, month 6 and month 12 will include completion of the Nutrition Assessment Shared Resources Food Frequency Questionnaire and a survey to assess frequency of healthy and unhealthy food purchases. Primary outcomes of interest are: (1) change in self-reported intake of sugar-sweetened beverages (SSBs); and (2) change in the frequency of healthy and unhealthy food purchases. Secondary outcomes include: (1) change in self-reported food budgeting skills; (2) change in self-reported cooking skills; and (3) a mixed-methods process evaluation to assess intervention reach, fidelity, satisfaction, and dose delivered/received.

Discussion

Targeted and sustainable interventions are needed to promote optimal health in rural AI communities. If effective, this intervention will reduce intake of SSBs and the purchase of unhealthy foods; increase the purchase of healthy foods; and improve healthy food budgeting and cooking skills among AIs with type 2 diabetes – a population at high risk of poor health outcomes. This work will help inform future health promotion efforts in resource-limited settings.

Trial registration

This study was registered on ClinicalTrials.gov on October 9, 2018 with Identifier NCT03699709.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10308-8.

Can Community Gardens with Workshops Increase Gardening Behavior? A Navajo Wellness Collaboration

This project evaluated the potential efficacy of a community gardening intervention on the Navajo Nation to increase gardening and healthy eating behaviors, which are potentially important in preventing obesity and related health conditions. Rates of obesity are high among American Indians, including those living on Navajo Nation land. Eating fresh fruits and vegetables is part of healthy eating. However, availability and access to fresh fruits and vegetables are severely limited due to distance and cost. One way to increase both availability and consumption of fresh fruits and vegetables is through community gardening, yet many on the Navajo Nation have limited knowledge and capacity to garden.

METHODS

We used a quasi-experimental pre-post study design to estimate the effect of a community gardening intervention. Primary outcomes of interest were gardening frequency and fruit and vegetable consumption. Community gardens were constructed and planted in two communities on the Navajo Nation. In addition, a series of gardening workshops were held in each community. Community members were recruited to complete surveys at time points before and after the workshops. The time between baseline and follow-up was approximately one year.

RESULTS

We surveyed 169 participants at one time point at least, across both communities, and 25 of these participated in the gardening workshops. Within the 169, there was a cohort of 32 participants completing both baseline and follow-up surveys. For this cohort, interest in gardening increased from 78% to 97% (p=0.014), but none of the changes in gardening self-efficacy, knowledge or gardening frequency reached statistical significance. There were no measurable changes in reported fruit and vegetable consumption, self-efficacy or knowledge. Overall, the reported financial barriers to gardening increased from baseline to follow-up from 4.6 to 5.5 (p=0.035). Among those who completed follow-up, those who attended at least one workshop gardened more frequently than those who did not attend any workshops (21 times per month compared to 10 times per month (p=0.065).

CONCLUSION

Despite enthusiasm for the community garden in both the communities studied and the increased interest in gardening, workshop attendance and participant retention in the study were low. These factors limited our ability to evaluate the potential efficacy of the intervention on gardening and healthy eating behaviors. Nonetheless, we found some evidence that participating in gardening workshops may lead to increased gardening frequency. Future studies should augment the intervention to include explicit efforts to reduce barriers to long term engagement and extend intervention reach.

Transdisciplinary research outcomes based on the Transdisciplinary Research on Energetics and Cancer II initiative experience

Intractable public health problems are influenced by interacting multi-level factors. Dynamic research approaches in which teams of scientists collaborate beyond traditional disciplinary, institutional, and geographic boundaries have emerged as promising strategies to address pressing public health priorities. However, little prior work has identified, defined, and characterized the outcomes of transdisciplinary (TD) research undertaken to address public health problems. Through a mixed methods approach, we identify, define, and characterize TD outcomes and their relevance to improving population health using the Transdisciplinary Research on Energetics and Cancer (TREC) II initiative as a case example. In Phase I, TREC II leadership (n = 10) identified nine initial TD outcomes. In Phase II (web-based survey; n = 23) and Phase III (interviews; n = 26; and focus groups, n = 23) TREC members defined and characterized each outcome. The resulting nine outcomes are described. The nine complementary TD outcomes can be used as a framework to evaluate progress toward impact on complex public health problems. Strategic investment in infrastructure that supports team development and collaboration, such as a coordination center, cross-center working groups, annual funded developmental projects, and face-to-face meetings, may foster achievement of these outcomes. This exploratory work provides a basis for the future investigation and development of quantitative measurement tools to assess the achievement of TD outcomes that are relevant to solving multifactorial public health problems.

Associations between Plasma Choline Metabolites and Genetic Polymorphisms in One-Carbon Metabolism in Postmenopausal Women: The Women's Health Initiative Observational Study

BACKGROUND

Choline plays an integral role in one-carbon metabolism in the body, but it is unclear whether genetic polymorphisms are associated with variations in plasma choline and its metabolites.

OBJECTIVES

This study aimed to evaluate the association of genetic variants in choline and one-carbon metabolism with plasma choline and its metabolites.

METHODS

We analyzed data from 1423 postmenopausal women in a case-control study nested within the Women's Health Initiative Observational Study. Plasma concentrations of choline, betaine, dimethylglycine (DMG), and trimethylamine N-oxide were determined in 12-h fasting blood samples collected at baseline (1993-1998). Candidate and tagging single-nucleotide polymorphisms (SNPs) were genotyped in betaine-homocysteine S-methyltransferase (BHMT), BHMT2, 5,10-methylenetetrahydrofolate reductase (MTHFR), methylenetetrahydrofolate dehydrogenase (NADP+ dependent 1) (MTHFD1), 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR), and 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR). Linear regression was used to derive percentage difference in plasma concentrations per variant allele, adjusting for confounders, including B-vitamin biomarkers. Potential effect modification by plasma vitamin B-12, vitamin B-6, and folate concentrations and folic-acid fortification periods was examined.

RESULTS

The candidate SNP BHMT R239Q (rs3733890) was associated with lower concentrations of plasma betaine and DMG concentrations (-4.00% and -6.75% per variant allele, respectively; both nominal P < 0.05). Another candidate SNP, BHMT2 rs626105 A>G, was associated with higher plasma DMG concentration (13.0%; P < 0.0001). Several tagSNPs in these 2 genes were associated with plasma concentrations after correction for multiple comparisons. Vitamin B-12 status was a significant effect modifier of the association between the genetic variant BHMT2 rs626105 A>G and plasma DMG concentration.

CONCLUSIONS

Genetic variations in metabolic enzymes were associated with plasma concentrations of choline and its metabolites. Our findings contribute to the knowledge on the variation in blood nutrient concentrations in postmenopausal women.

Women's beliefs about what causes obesity: variation by race/ethnicity and acculturation in a Washington State sample

Objective: Individuals' beliefs about the causes of multifactorial health conditions (causal attributions) shape how they conceptualize and respond to health threats and are therefore important for health promotion. Studies of racial/ethnic and cultural variation in obesity causal beliefs, however, are scarce. To address this gap, this study described beliefs about the underlying causes of obesity (genetic inheritance, diet, and physical activity) in Hispanic and non-Hispanic White women participating in a longitudinal cohort study in South King County, Washington State (n = 1,002).Design: Analysis of baseline survey data. Self-reported obesity causal beliefs were compared by race/ethnicity and acculturation indicators (survey language and nativity) using marginal effect estimates generated from multinomial logistic regression models.Results: Hispanic women had a higher probability of not believing 'at all' in inheritance and physical activity as causes of obesity - an absolute increase of 33% and 5% over non-Hispanic White women, respectively. Both acculturation indicators were also associated with a higher probability of not believing 'at all' in inheritance as a cause of obesity, though Hispanic women who completed the survey in English and were born in the United States had genetic causal beliefs similar to non-Hispanic White women. Behavioral attributions did not vary by acculturation indicators in Hispanic women.Conclusions: Differences in obesity casual beliefs, particularly genetic attributions, exist and may be important for developing and delivering effective obesity-related health promotion interventions. Identifying the determinants and public health consequences of cultural variation in obesity attributions should be the focus of future research.

Artificially Sweetened Beverages and Stroke, Coronary Heart Disease, and All-Cause Mortality in the Women's Health Initiative

Background and Purpose- We examine the association between self-reported consumption of artificially sweetened beverages (ASB) and stroke and its subtypes, coronary heart disease, and all-cause mortality in a cohort of postmenopausal US women. Methods- The analytic cohort included 81 714 women from the Women's Health Initiative Observational Study, a multicenter longitudinal study of the health of 93 676 postmenopausal women of ages 50 to 79 years at baseline who enrolled in 1993 to 1998. This prospective study had a mean follow-up time of 11.9 years (SD of 5.3 years.) Participants who completed a follow-up visit 3 years after baseline were included in the study. Results- Most participants (64.1%) were infrequent consumers (never or <1/week) of ASB, with only 5.1% consuming ≥2 ASBs/day. In multivariate analyses, those consuming the highest level of ASB compared to never or rarely (<1/wk) had significantly greater likelihood of all end points (except hemorrhagic stroke), after controlling for multiple covariates. Adjusted models indicated that hazard ratios and 95% confidence intervals were 1.23 (1.02-1.47) for all stroke; 1.31 (1.06-1.63) for ischemic stroke; 1.29 (1.11-1.51) for coronary heart disease; and 1.16 (1.07-1.26) for all-cause mortality. In women with no prior history of cardiovascular disease or diabetes mellitus, high consumption of ASB was associated with more than a 2-fold increased risk of small artery occlusion ischemic stroke hazard ratio =2.44 (95% confidence interval, 1.47-4.04.) High consumption of ASBs was associated with significantly increased risk of ischemic stroke in women with body mass index ≥30; hazard ratio =2.03 (95% confidence interval, 1.38-2.98). Conclusions- Higher intake of ASB was associated with increased risk of stroke, particularly small artery occlusion subtype, coronary heart disease, and all-cause mortality. Although requiring replication, these new findings add to the potentially harmful association of consuming high quantities of ASB with these health outcomes.

Eating Occasions, Obesity and Related Behaviors in Working Adults: Does it Matter When You Snack?

Reported relationships between frequency, type, and timing of eating occasions and obesity-risk among adults are mixed while associations with obesogenic eating behaviors remain unexplored. The Physical Activity and Changes in Eating (PACE) study was a group-randomized controlled trial to prevent weight gain among 34 small worksites in Seattle from 2005-2009. Baseline surveys assessed body mass index (BMI), obesogenic eating behaviors (e.g., fast food and distracted-eating), and eating occasions (i.e., snacks and meals) among 2265 employees. BMI and waist circumference were measured on a subset (n = 567). Time-periods for analyses included: morning (12:00 a.m. to 10:59 a.m.), mid-day (11:00 a.m. to 4:29 p.m.), and evening (4:30 p.m. to 11:59 p.m.). Multilevel linear models estimated associations between snack timing, obesity, and related behaviors while adjusting for meal timing, gender, and worksite random effects. Greater morning snacking was associated with increased fruit and vegetable consumption, while greater evening snacking was associated with higher BMI, higher obesogenic dietary index (intake of fast food, French fries, and soft drinks), and higher percent time eating while distracted. Associations with mid-day snacking were mixed. Patterns of association were consistent across repeated and objective measures. Findings suggest that evening snacking is more detrimental to healthy weight compared to snacking at other times of day. Reducing evening snacks may be an important and simple message for population-level obesity prevention efforts.

Gardening for Health: Patterns of Gardening and Fruit and Vegetable Consumption Among the Navajo

American Indians, including Navajo, are disproportionately affected by obesity and diabetes, in part due to diet-related health behaviors. The purpose of this study was to assess the patterns of gardening and fruit and vegetable (FV) consumption among residents in two communities on the Navajo Nation in order to inform a community gardening intervention. We analyzed survey data collected from participants in the Yéego Gardening study conducted in two communities in the Navajo Nation (N = 169). We found that 51% of the sample gardened, and on average participants gardened 8.9 times per month. Lack of time (53%) and financial barriers, such as gas for transportation or irrigation (51 and 49%, respectively), were reported as barriers to gardening. Most participants reported low levels of self-efficacy (80%) and behavioral capability (82%) related to gardening. Those with higher levels of gardening self-efficacy and behavioral capability reported more frequent gardening. Average daily FV consumption was 2.5 servings. Most participants reported high levels of self-efficacy to eat FV daily (64%) and high behavioral capability to prepare FV (66%). There was a positive association between FV consumption and gardening, with those gardening more than 4 times per month eating about 1 more serving of FV per day than those gardening 4 or fewer times per month. Further research is needed to better understand how gardening can increase fruit and vegetable availability and consumption among residents of the Navajo Nation.

Low-Fat Dietary Pattern and Cancer Mortality in the Women's Health Initiative (WHI) Randomized Controlled Trial

Background

In the Women’s Health Initiative Dietary Modification trial, a low-fat dietary pattern reduced deaths after breast cancer. Mortality from other cancer sites has not been reported.

Methods

A low-fat dietary pattern influence on deaths from and after site-specific cancers was examined during 8.5 years (median) of dietary intervention and cumulatively during 17.7 years (median) of follow-up. A total 48 835 postmenopausal women, ages 50–79 years, were randomly assigned from 1993 to 1998 at 40 US clinical centers to dietary intervention (40%, n = 19 541 or a usual diet comparison group (60%, n = 29 294). Dietary intervention influence on mortality from protocol-specified cancers (breast, colon and rectum, endometrium and ovary), individually and as a composite, represented the primary analyses.

Results

During the dietary intervention period, a reduction in deaths after breast cancer (HR = 0.65 95% CI = 0.45 to 0.94, P = .02) was the only statistically significant cancer mortality finding. During intervention, the HRs for deaths after the protocol-specified cancer composite were 0.90 (95% CI = 0.73 to 1.10) and 0.95 (95% CI = 0.85 to 1.06) for deaths after all cancers. During 17.7 years of follow-up with 3867 deaths after all cancers, reduction in deaths after breast cancer continued in the dietary intervention group (HR = 0.85, 95% CI = 0.74 to 0.99, P = .03). However, no dietary intervention influence on deaths from or after any other cancer or cancer composite was seen.

Conclusions

A low-fat dietary pattern reduced deaths after breast cancer. No reduction in mortality from or after any other cancer or cancer composite was seen.

Understanding Complex Roles of Family for Latina Health: Evaluating Family Obligation Stress

We developed a measure of family obligation stress and compared its relationship to health and unmet health care needs relative to social support among a sample of US-based Latinas. Data come from a randomized controlled trial within 4 clinics to increase mammography among Latinas (n = 539). The 1-factor measure had acceptable reliability and construct validity. Family obligation stress was associated with worse health and greater unmet health care needs. Family obligation stress varied by years in the United States and country of origin. Our measure of family obligation stress contributes new venues to family research among Latino populations.

Serum Nitrogen and Carbon Stable Isotope Ratios Meet Biomarker Criteria for Fish and Animal Protein Intake in a Controlled Feeding Study of a Women's Health Initiative Cohort

Background

Natural abundance stable isotope ratios are candidate biomarkers of dietary intake that have not been evaluated in a controlled feeding study in a US population.

Objectives

Our goals were to evaluate dietary associations with serum carbon (CIR), nitrogen (NIR), and sulfur (SIR) isotope ratios in postmenopausal women, and to evaluate whether statistical models of dietary intake that include multiple isotopes and participant characteristics meet criteria for biomarker evaluation.

Methods

Postmenopausal women from the Women's Health Initiative (n = 153) were provided a 2-wk controlled diet that approximated each individual's habitual food intake. Dietary intakes of animal protein, fish/seafood, red meat, poultry, egg, dairy, total sugars, added sugars, sugar-sweetened beverages (SSBs), and corn products were characterized during the feeding period with the use of the Nutrition Data System for Research (NDS-R). The CIR, NIR, and SIR were measured in sera collected from fasting women at the beginning and the end of the feeding period. Linear models based on stable isotope ratios and participant characteristics predicted dietary intake. The criterion used for biomarker evaluation was R2 ≥ 0.36, based on the study's power to detect true associations with R2 ≥ 0.50.

Results

The NIR was associated with fish/seafood intake and met the criterion for biomarker evaluation (R2 = 0.40). The CIR was moderately associated with intakes of red meat and eggs, but not to the criterion for biomarker evaluation, and was not associated with intake of sugars (total, added, or SSB). A model of animal protein intake based on the NIR, CIR, and participant characteristics met the criterion for biomarker evaluation (R2 = 0.40). Otherwise, multiple isotopes did not improve models of intake, and improvements from including participant characteristics were modest.

Conclusion

Serum stable isotope ratios can, with participant characteristics, meet biomarker criteria as measures of fish/seafood and animal protein intake in a sample of postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00000611.

Environmental and Individual Predictors of Healthy Dietary Behaviors in a Sample of Middle Aged Hispanic and Caucasian Women

The objective of this effort is to gather data to tailor interventions appropriately. Greater understanding of the correlates of socioeconomic status and obesogenic dietary behaviors was the focus of this manuscript. Using multistage sampling, women with varied education levels completed a baseline assessment in a longitudinal study of women aged 30 to 50 years. This study was conducted in low-SES areas of South King County, Washington State. This study included 530 Caucasian and 510 Hispanic women. Fruit and vegetable consumption was positively associated and soft drink consumption inversely associated with the level of education in Caucasian women. In contrast, percentage calories from fat was positively associated with the level of education in Hispanic women. In Hispanic women, level of education interacted significantly with food security in relation to percentage calories from fat, and with eating norms in relation to soft drink consumption. Neighborhood presence of ethnic food stores was associated with outcomes for Hispanic women, but for Caucasians, presence of fast food restaurants was important. Education was consistently associated with two of the three obesogenic dietary behaviors studied among Caucasian women. Education played a moderating role in the associations of food security and eating norms, independent of area level food availability, in two of three obesogenic dietary behaviors studied. However, these patterns differed for Hispanic women, indicating the need for more research into important variables to support change in Hispanic women. Women of differing ethnic groups did not respond similarly to environmental conditions and policy-relevant surroundings. These data have meaning for considering urban policy that impacts obesity levels in the population.

Association between iq'mik smokeless tobacco use and cardiometabolic risk profile among Yup'ik Alaska Native people

OBJECTIVE

The traditional lifestyle of Yup'ik Alaska Native people, including a diet abundant in marine-based foods and physical activity, may be cardio-protective. However, iq'mik, a traditional form of smokeless tobacco used by >50% of Yup'ik adults, could increase cardiometabolic (CM) risk. Our objective was to characterize the associations between iq'mik use and biomarkers of CM status (low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], triglycerides [TG], systolic blood pressure [SBP] and diastolic blood pressure [DBP], glycated hemoglobin [HbA1c], fasting blood glucose [FBG], waist circumference [WC], and body mass index [BMI]).

DESIGN

We assessed these associations using data from a cross-sectional sample of Yup'ik adults (n = 874). Current iq'mik use, demographic, and lifestyle data were collected through interviews. Fasting blood samples were collected to measure LDL-C, HDL-C, TG, HbA1c, and FBG. SBP, DBP, WC, and BMI were obtained by physical examination. We characterized the association between current iq'mik use and continuous biomarkers of CM status using multiple approaches, including adjustment for measures of Yup'ik lifestyle and a propensity score.

RESULTS

Based on either adjustment method, current iq'mik use was significantly and positively associated with at least 5% higher HDL-C, and significantly associated but in an inverse direction with multiple biomarkers of CM status including 7% lower TG, 0.05% lower HbA1c, 2% lower FBG, 4% lower WC, and 4% lower BMI. Observed associations for LDL-C, SBP, and DBP varied by adjustment method.

CONCLUSIONS

This inverse association between iq'mik use and cardiometabolic risk status has not been previously reported. Additional research is needed to replicate these findings and explore physiological mechanisms and/or confounding factors.

Applying Multiple Statistical Methods to Derive an Index of Dietary Behaviors Most Related to Obesity

To evaluate the success of dietary interventions, we need measures that are more easily assessed and that closely align with intervention messaging. An index of obesogenic dietary behaviors (e.g., consumption of fast food and soft drinks, low fruit and vegetable consumption, and task eating (eating while engaging in other activities)) may serve this purpose and could be derived via data-driven methods typically used to describe nutrient intake. We used behavioral and physical measurement (i.e., body mass index, waist circumference) data from a subset of 2 independent cross-sectional samples of employees enrolled in the Promoting Activity and Changes in Eating (PACE) Study (Seattle, Washington) who were selected at baseline (2005-2007) (n = 561) and during follow-up (2007-2009) (n = 155). Index derivation methods, including principal components regression, partial least squares regression, and reduced rank regression, were compared. The best-fitting index for predicting physical measurements included consumption of fast food, French fries, and soft drinks. In linear mixed models, each 1-quartile increase in index score was associated with a 5% higher baseline body mass index (ratio of geometric means = 1.053, 95% confidence interval: 1.031, 1.075) and an approximately 4% higher baseline waist circumference (ratio = 1.036, 95% confidence interval: 1.019, 1.054) after adjustment for covariates. Results were similar at follow-up before and after adjustment for baseline measures. This index may be useful in evaluating public health or clinic-based dietary interventions to reduce obesity, especially given the ubiquity of these behaviors in the general population.

Estimating the costs and cost-effectiveness of promoting mammography screening among US-based Latinas

PURPOSE

We characterize the costs and cost-effectiveness of a community health worker (CHW)-based intervention to promote screening mammography among US-based non-adherent Latinas.

METHODS

The parent study was a randomized controlled trial for 536 Latinas aged 42-74 years old who had sought care within a safety net health center in Western Washington. Participants were block-randomized within clinic to the control arm (usual care) or intervention arm (CHW-led motivational interviewing intervention). We used the perspective of the organization implementing promotional activities to characterize costs and cost-effectiveness. Cost data were categorized as program set-up and maintenance (initial training, booster/annual training) program implementation (administrative activities, intervention delivery); and, overhead/miscellaneous expenses. Cost-effectiveness was calculated as the incremental cost of screening for each additional woman screened between the intervention and control arms.

RESULTS

The respective costs per participant for standard care and the intervention arm were $69.96 and $300.99. There were no study arm differences in 1-year QALYs were small among women who completed a 12-month follow-up survey (intervention= 0.8827, standard care = 0.8841). Most costs pertained to program implementation and administrative activities specifically. The incremental cost per additional woman screened was $2,595.32.

CONCLUSIONS

Our findings are within the ranges of costs and cost-effectiveness for other CHW programs to promote screening mammography among underserved populations. Our strong study design and focus on non-adherent women provides important strengths to this body of work, especially give implementation and dissemination science efforts regarding CHW-based health promotion for health disparity populations.

Mobile Versus Fixed Facility: Latinas' Attitudes and Preferences for Obtaining a Mammogram

PURPOSE

Mobile mammographic services have been proposed as a way to reduce Latinas' disproportionate late-stage presentation compared with white women by increasing their access to mammography. The aims of this study were to assess why Latinas may not use mobile mammographic services and to explore their preferences after using these services.

METHODS

Using a mixed-methods approach, a secondary analysis was conducted of baseline survey data (n = 538) from a randomized controlled trial to improve screening mammography rates among Latinas in Washington. Descriptive statistics and bivariate regression were used to characterize mammography location preferences and to test for associations with sociodemographic indices, health care access, and perceived breast cancer risk and beliefs. On the basis of these findings, a qualitative study (n = 18) was used to explore changes in perceptions after using mobile mammographic services.

RESULTS

More Latinas preferred obtaining a mammogram at a fixed facility (52.3% [n = 276]) compared with having no preference (46.3% [n = 249]) and preferring mobile mammographic services (1.7% [n = 9]). Concerns about privacy and comfort (15.6% [n = 84]) and about general quality (10.6% [n = 57]) were common reasons for preferring a fixed facility. Those with no history of mammography preferred a fixed facility (P < .05). In the qualitative study, Latinas expressed similar initial concerns but became positive toward the mobile mammographic services after obtaining a mammogram.

CONCLUSIONS

Although most Latinas preferred obtaining a mammogram at a fixed facility, positive experiences with mobile mammography services changed their attitudes toward them. These findings highlight the need to include community education when using mobile mammographic service to increase screening mammography rates in underserved communities.

Associations between neighbourhood characteristics and depression: a twin study

BACKGROUND

Depression is an important contributor to the global burden of disease. Besides several known individual-level factors that contribute to depression, there is a growing recognition that neighbourhood environment can also profoundly affect mental health. This study assessed associations between three neighbourhood constructs-socioeconomic deprivation, residential instability and income inequality-and depression among adult twin pairs. The twin design is used to examine the association between neighbourhood constructs and depression, controlling for selection factors (ie, genetic and shared environmental factors) that have confounded purported associations.

METHODS

We used multilevel random-intercept Poisson regression among 3738 same-sex twin pairs from a community-based twin registry to examine the association between neighbourhood constructs and depression. The within-pair association controls for confounding by genetic and environmental factors shared between twins within a pair, and is the main parameter of interest. Models were adjusted for individual-level income, education and marital status, and further by neighbourhood-level population density.

RESULTS

When twins were analysed as individuals (phenotypic model), all neighbourhood constructs were significantly associated with depression. However, only neighbourhood socioeconomic deprivation showed a significant within-pair association with depression. A 10-unit within-pair difference in neighbourhood socioeconomic deprivation was associated with 6% greater depressive symptoms (1.06, 95% CI 1.01 to 1.11); the association did not substantially change in adjusted models.

CONCLUSION

This study provides new evidence linking neighbourhood socioeconomic deprivation with greater depression. Future studies should employ longitudinal designs to better test social causation versus social selection.

Healthcare Factors for Obtaining a Mammogram in Latinas With a Variable Mammography History

PURPOSE/OBJECTIVES

To understand the relationship between mammography history and current thoughts about obtaining a mammogram among Latinas and examine the mediation effects of several healthcare factors.
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DESIGN

Cross-sectional survey.
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SETTING

Federally qualified health centers (Sea Mar Community Health Centers) in western Washington.
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SAMPLE

641 Latinas nonadherent and adherent with screening mammography.
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METHODS

Baseline survey data from Latinas with a mammography history of never, not recent (more than two years), or recent (less than two years) were analyzed. Preacher and Hayes methods were used to estimate the mediation effect of healthcare factors.
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MAIN RESEARCH VARIABLES

The survey assessed mammography history, sociodemographic and healthcare factors, and current thoughts about obtaining a mammogram.
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FINDINGS

Latinas' thoughts about obtaining a mammogram were associated with mammography history. Having had a clinical breast examination mediated 70% of differences between Latinas with a never and recent mammography history. Receipt of a provider recommendation mediated 54% of differences between Latinas with and without a recent mammography history.
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CONCLUSIONS

These findings emphasize the importance of the patient-provider relationship during a clinic visit and help inform how nurses may be incorporated into subsequent screening mammography interventions tailored to Latinas.
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IMPLICATIONS FOR NURSING

As providers, health educators, and researchers, nurses have critical roles in encouraging adherence to screening mammography guidelines among Latinas.

Serum 25-hydroxyvitamin D concentrations and lung cancer risk in never-smoking postmenopausal women

PURPOSE

Vitamin D has been implicated in lowering lung cancer risk, but serological data on the association among never-smoking women are limited. We report results examining the association of serum 25-hydroxyvitamin D [25(OH)D] concentrations with lung cancer risk among female never smokers. We also examined whether the association was modified by vitamin D supplementation and serum vitamin A concentrations.

METHODS

In the Women's Health Initiative, including the calcium/vitamin D (CaD) Trial, we selected 298 incident cases [191 non-small cell lung cancer (NSCLC) including 170 adenocarcinoma] and 298 matched controls of never smokers. Baseline serum 25(OH)D was assayed by a chemiluminescent method. Logistic regression was used to estimate odds ratios (ORs) for quartiles and predefined clinical cutoffs of serum 25(OH)D concentrations.

RESULTS

Comparing quartiles 4 versus 1 of serum 25(OH)D concentrations, ORs were 1.06 [95% confidence interval (CI) 0.61-1.84] for all lung cancer, 0.94 (95% CI 0.52-1.69) for NSCLC, and 0.91 (95% CI 0.49-1.68) for adenocarcinoma. Comparing serum 25(OH)D ≥ 75 (high) versus <30 nmol/L (deficient), ORs were 0.76 (95% CI 0.31-1.84) for all lung cancer, 0.71 (95% CI 0.27-1.86) for NSCLC, and 0.81 (95% CI 0.31-2.14) for adenocarcinoma. There is suggestive evidence that CaD supplementation (1 g calcium + 400 IU D₃/day) and a high level of circulating vitamin A may modify the associations of 25(OH)D with lung cancer overall and subtypes (p interaction <0.10).

CONCLUSIONS

In this group of never-smoking postmenopausal women, the results did not support the hypothesis of an association between serum 25(OH)D and lung cancer risk.

Conversations about Abnormal Mammograms on Distress and Timely Follow-up Across Ethnicity

Communication with healthcare providers, family, and friends is associated with increased mammography use. Less is known about the abnormal mammogram experience, especially in terms of the interval between screening and follow-up appointments (time to follow-up) and psychological distress. The impact of communication may vary across ethnicity, depending on cultural emphases placed on interpersonal relationships. The current study's objectives were to (a) explore the role of family/friend and provider communication with regard to time to follow-up and distress and (b) examine if family/friend and provider communication moderates associations between ethnicity and these outcomes. A convenience-based sample of 41 Latina and 41 non-Latina White (NLW) women who had received an abnormal mammogram result was recruited from Washington State. Women who discussed results with providers had a shorter time to follow-up, although this was not significant when including health insurance. A significant interaction between conversations with family/friends and ethnicity was found: Latinas who did not have conversations with family/friends had particularly elevated psychological distress relative to NLW women and slightly more than other Latinas. This exploratory study suggests health communication with providers and family/friends is important for timely receipt of follow-up care and reduced distress among women who receive an abnormal mammogram result, which has implications for cancer education intervention development and adaptation. Larger, population-based research is necessary to confirm these findings.

Long-Term Oral Bisphosphonate Therapy and Fractures in Older Women: The Women's Health Initiative

OBJECTIVES

To examine the association between long-term bisphosphonate use and fracture in older women at high risk of fracture.

DESIGN

Retrospective cohort.

SETTING

Women's Health Initiative.

PARTICIPANTS

Older women who reported at least 2 years of bisphosphonate use in 2008-09 (N = 5,120).

MEASUREMENTS

Exposure data were from a current medications inventory. Outcomes (hip, clinical vertebral, wrist or forearm, any clinical fracture) were ascertained annually. Using multivariate Cox proportional hazards models, the association between duration of bisphosphonate use (3-5, 6-9, 10-13 years) and fracture was estimated, using 2 years as the referent group.

RESULTS

On average participants were 80 years old and were followed for 3.7 ± 1.2 years. There were 127 hip, 159 wrist or forearm, 235 clinical vertebral, and 1,313 clinical fractures. In multivariate-adjusted analysis, 10 to 13 years of bisphosphonate use was associated with higher risk of any clinical fracture than 2 years of use (hazard ratio (HR) = 1.29, 95% confidence interval (CI) = 1.07-1.57). This association persisted in analyses limited to women with a prior fracture (HR = 1.30, 95% CI = 1.01-1.67) and women with no history of cancer (HR = 1.36, 95% CI = 1.10-1.68). The association of 10 to 13 years of use, compared with 2 years of use, was not statistically significant for hip (HR = 1.66, 95% CI = 0.81-3.40), clinical vertebral (HR = 1.65, 95% CI = 0.99-2.76), or wrist fracture (HR = 1.16, 95% CI = 0.67-2.00).

CONCLUSION

In older women at high risk of fracture, 10 to 13 years of bisphosphonate use was associated with higher risk of any clinical fracture than 2 years of use. These results add to concerns about the benefit of very long-term bisphosphonate use.

Psychological Outcomes After a False Positive Mammogram: Preliminary Evidence for Ethnic Differences Across Time

Adverse psychological consequences of screening mammography are well-documented for women who receive a false positive result. However, little is known about ethnic differences. To address this gap, we examine distress associated with an abnormal mammogram (results-related distress) and perceived lifetime risk of breast cancer (perceived risk) among Latinas and non-Latina White (NLW) women 3 months after receipt of a false positive result. A sample of 28 Latina and 27 NLW women who received an initial abnormal mammogram result and later, a definitive non-cancer diagnosis were recruited for this descriptive, longitudinal study. Women were interviewed twice: within 30 days and 3 months after a false positive result. Questionnaires included standard sociodemographic questions, the Impact of Events Scale-Revised, and two perceived breast cancer risk items. All participants experienced decreased distress 3 months after the initial results. Latinas experienced higher levels of distress, F(1,45) = 4.58, p = 0.04, and had a significant increase in perceived breast cancer risk over time, F(1,45) = 3.99, p = 0.05. Larger population-based studies are necessary to confirm ethnic differences in mental health consequences of false positive results. Given cultural emphases concerning respect for authority figures, healthcare professionals may be particularly helpful in working with Latinas to mitigate distress and clarify accurate perceptions of breast cancer risk through evidence-based practice.

Multilevel Intervention Raises Latina Participation in Mammography Screening: Findings from ¡Fortaleza Latina!

BACKGROUND

Breast cancer is the most commonly diagnosed cancer in women in the United States, and Latinas have relatively low rates of screening participation. The Multilevel Intervention to Increase Latina Participation in Mammography Screening study (¡Fortaleza Latina!) sought to assess the efficacy of a clinic- and patient-level program to increase breast cancer screening among Latinas in Western Washington who seek care at a safety net health center.

METHODS

The study enrolled 536 Latinas ages 42 to 74 who had a primary care clinic visit in the previous 5 years and had not obtained a mammogram in the previous 2 years. Participants were block-randomized within clinic to either (i) a control arm (usual care) or (ii) a promotora-led, motivational interviewing intervention that included a home visit and telephone follow-up. At the clinic level, two of four participating clinics were provided additional mammography services delivered by a mobile mammography unit.

RESULTS

Rates of screening mammography 1 year post-randomization were 19.6% in the intervention group and 11.0% in the usual care group (P < 0.01), based on medical record data. No significant differences in participants' mammography screening were observed in clinics randomized to additional mammography services versus usual care (15.8% vs. 14.4%; P = 0.68).

CONCLUSION

This multilevel intervention of promotora-delivered motivational interviewing and free mammography services modestly raised rates of participation in breast cancer screening among Latinas.

IMPACT

Our findings can inform future efforts to boost mammography participation in safety net practices. Cancer Epidemiol Biomarkers Prev; 25(4); 584-92. ©2016 AACR SEE ALL ARTICLES IN THIS CEBP FOCUS SECTION, "MULTILEVEL APPROACHES TO ADDRESSING CANCER HEALTH DISPARITIES".

Reproducibility and relative validity of food group intake in a food frequency questionnaire developed for Nepalese diet

We developed a food frequency questionnaire (FFQ) designed to measure the dietary practices of adult Nepalese. The present study examined the validity and reproducibility of the FFQ. To evaluate the reproducibility of the FFQ, 116 subjects completed two 115-item FFQ across a four-month interval. Six 24-h dietary recalls were collected (1 each month) to assess the validity of the FFQ. Seven major food groups and 23 subgroups were clustered from the FFQ based on macronutrient composition. Spearman correlation coefficients evaluating reproducibility for all food groups were greater than 0.5, with the exceptions of oil. The correlations varied from 0.41 (oil) to 0.81 (vegetables). All crude spearman coefficients for validity were greater than 0.5 except for dairy products, pizzas/pastas and sausage/burgers. The FFQ was found to be reliable and valid for ranking the intake of food groups for Nepalese dietary intake.

The Interaction between Dietary Fiber and Fat and Risk of Colorectal Cancer in the Women's Health Initiative

Combined intakes of specific dietary fiber and fat subtypes protect against colon cancer in animal models. We evaluated associations between self-reported individual and combinations of fiber (insoluble, soluble, and pectins, specifically) and fat (omega-6, omega-3, and docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), specifically) and colorectal cancer (CRC) risk in the Women's Health Initiative prospective cohort (n = 134,017). During a mean 11.7 years (1993-2010), 1952 incident CRC cases were identified. Cox regression models computed multivariate adjusted hazard ratios to estimate the association between dietary factors and CRC risk. Assessing fiber and fat individually, there was a modest trend for lower CRC risk with increasing intakes of total and insoluble fiber (p-trend 0.09 and 0.08). An interaction (p = 0.01) was observed between soluble fiber and DHA + EPA, with protective effects of DHA + EPA with lower intakes of soluble fiber and an attenuation at higher intakes, however this association was no longer significant after correction for multiple testing. These results suggest a modest protective effect of higher fiber intake on CRC risk, but not in combination with dietary fat subtypes. Given the robust results in preclinical models and mixed results in observational studies, controlled dietary interventions with standardized intakes are needed to better understand the interaction of specific fat and fiber subtypes on colon biology and ultimately CRC susceptibility in humans.

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.

Validity of Self-Reported Medication Use Compared With Pharmacy Records in a Cohort of Older Women: Findings From the Women's Health Initiative

Inaccurate self-reported data on medication exposure lead to less reliable study findings. From 2013 to 2015, we assessed the validity of information on medication use collected via a mailed medication inventory among 223 Women's Health Initiative participants who were members of a health-care delivery system. Self-reported information on medication use was compared with pharmacy records for statins, calcium channel blockers, β-blockers, and bisphosphonates. We assessed sensitivity, specificity, and positive predictive value (PPV) for current medication use. We assessed agreement on duration of use (<2, 2, 3, 4, or ≥5 years) by means of the weighted κ statistic. The mean age of participants was 77 years. Statins, β-blockers, and calcium channel blockers were each reported by over 15% of women, and bisphosphonates were reported by 4.5%. Compared with pharmacy records, the sensitivity, specificity, and PPV for self-reported use of statins, β-blockers, and calcium channel blockers were all 95% or greater. The sensitivity and PPV for bisphosphonate use were both 80% (95% confidence interval: 44, 97), and specificity was 99% (95% confidence interval: 97, 100). The κ statistic for duration of use was 0.87 or greater for all 4 medication classes. Compared with pharmacy records, self-reported information on current medication use and duration of use collected via mailed medication inventory among older women had almost perfect agreement for use of statins, β-blockers, and calcium channel blockers.

Neighborhood Predictors of Mammography Barriers Among US-Based Latinas

BACKGROUND

Little is known about how neighborhood factors are associated with Latinas' barriers to cancer screening, including mammography. To address this gap, we examined barriers to mammography by neighborhood racial/ethnic composition and socioeconomic status among a federally qualified health center (FQHC)-based sample of non-adherent Latinas in Western Washington State.

METHODS

Baseline data were drawn from a larger intervention study (n = 536 Latinas). Women indicated why they had not obtained a mammogram in the past 2 years (no reason, knowledge, psychocultural, economic). American Community Survey (2007-2011) data were used to calculate four neighborhood measures that were categorized in tertiles (T): socioeconomic-based concentration, socioeconomic-based segregation, Latino-based concentration, and Latino-based segregation.

RESULTS

The proportion of women reporting knowledge-, psychocultural-, and economic-based reasons for not obtaining mammograms in the past 2 years was, respectively, 0.35, 0.19, and 0.31. Approximately 14 % indicated no particular reason. Relative to women residing in areas with greater Latino-based segregation, women in areas with less Latino-based segregation were less likely to report knowledge-based and economic-based reasons for not obtaining a mammogram (p ≤ 0.05). Relative to women residing in areas with greater concentration of Latinos, women in areas with the lowest concentrations were less likely to report knowledge-based reasons for not obtaining a mammogram (p ≤ 0.05).

CONCLUSIONS

Our findings provide important information about the role of neighborhood characteristics and mammography use among Latinas obtaining care from FQHCs. Future research might examine the mediating role of neighborhood characteristics in the efficacy of mammography screening interventions.

Food patterns measured by principal component analysis and obesity in the Nepalese adult

OBJECTIVE

About one-fourth of Nepalese adults are overweight or obese but no studies have examined their risk factors, especially pertaining to diet. The present study aimed to identify dietary patterns in a suburban Nepalese community and assess their associations with overweight and obesity prevalence.

METHODS

This cross-sectional study used data from 1073 adults (18 years or older) participating in the baseline survey of the Dhulikhel Heart Study. We derived major dietary patterns from a principal component analysis of reported intake from a Food Frequency Questionnaire. Overweight was defined as Body Mass Index (BMI) of 25 kg/m(2) or higher and obesity was defined as BMI of 30 kg/m(2) or higher. Statistical analysis was conducted using generalised estimating equations with multivariate logistic regression (with household as cluster) adjusting for age, sex, ethnicity, religion, marital status, income, education, alcohol consumption, smoking, physical activity and systolic blood pressure.

RESULTS

Four dietary patterns were derived: mixed, fast food, refined grain-meat-alcohol and solid fats-dairy. The refined grain-rice-alcohol pattern was significantly associated with overweight (adjusted OR 1.19, 95% CI 1.03 to 1.39; p=0.02) after adjusting for demographic and traditional cardiovascular risk factors. In adults of 40 years or older, the fast food pattern was associated with obesity controlling for demographic and traditional risk factors (adjusted OR 1.69, 95% CI 1.19 to 2.39; p value=0.003).

CONCLUSIONS

Our results suggest that refined grains-meat-alcohol intake is associated with higher prevalence of overweight, and fast food intake is associated with higher prevalence of obesity in older adults (40 years or above) in suburban Nepalese adults.

Identifying the effects of environmental and policy change interventions on healthy eating

Obesity has been characterized as a disease. Strategies to change the incidence and prevalence of this disease include a focus on changing physical and social environments, over and above individual-level strategies, using a multilevel or systems approach. We focus our attention on evidence published between 2008 and 2013 on the effectiveness of interventions in nutrition environments, i.e., environmental interventions designed to influence the intake of healthful foods and amount of energy consumed. An overarching socioecological framework that has guided much of this research was used to characterize different types of environmental strategies. Intervention examples in each area of the framework are provided with a discussion of key findings and related conceptual and methodological issues. The emphasis in this review is on adults, but clearly this literature is only one part of the picture. Much research has been focused on child-specific interventions, including environmental interventions. Some evidence suggests effectiveness of policy-based or other types of interventions that aim to regulate or restructure environments to promote healthy dietary choices, and these strategies would apply to both children and adults. Opportunities to evaluate these policy changes in adults' social and physical environments are rare. Much of the existing research has been with children. As conceptual and methodological issues continue to be identified and resolved, we hope that future research in this domain will identify environmental strategies that can be included in intervention toolboxes to build healthy nutrition environments for both adults and children.

Genetic causal beliefs about obesity, self-efficacy for weight control, and obesity-related behaviours in a middle-aged female cohort

OBJECTIVE

Obesity is a heritable condition with well-established risk-reducing behaviours. Studies have shown that beliefs about the causes of obesity are associated with diet and exercise behaviour. Identifying mechanisms linking causal beliefs and behaviours is important for obesity prevention and control.

DESIGN

Cross-sectional multi-level regression analyses of self-efficacy for weight control as a possible mediator of obesity attributions (diet, physical activity, genetic) and preventive behaviours in 487 non-Hispanic White women from South King County, Washington.

MAIN OUTCOME MEASURES

Self-reported daily fruit and vegetable intake and weekly leisure-time physical activity.

RESULTS

Diet causal beliefs were positively associated with fruit and vegetable intake, with self-efficacy for weight control partially accounting for this association. Self-efficacy for weight control also indirectly linked physical activity attributions and physical activity behaviour. Relationships between genetic causal beliefs, self-efficacy for weight control, and obesity-related behaviours differed by obesity status. Self-efficacy for weight control contributed to negative associations between genetic causal attributions and obesity-related behaviours in non-obese, but not obese, women.

CONCLUSION

Self-efficacy is an important construct to include in studies of genetic causal beliefs and behavioural self-regulation. Theoretical and longitudinal work is needed to clarify the causal nature of these relationships and other mediating and moderating factors.

Associations between diet and cardiometabolic risk among Yup'ik Alaska Native people using food frequency questionnaire dietary patterns

BACKGROUND AND AIMS

In previous analyses, we identified three dietary patterns from food frequency questionnaire data among a sample of Yup'ik Alaska Native people living in Southwest Alaska: a "subsistence foods" dietary pattern and two market-based dietary patterns "processed foods" and "fruits and vegetables". In this analysis, we aimed to characterize the association between the dietary patterns and cardiometabolic (CM) risk factors (lipids, blood pressure, glucose, adiposity).

METHODS AND RESULTS

We used multilevel linear regression to estimate the mean of each CM risk factor, comparing participants in the 4th to the 1st quartile of each dietary pattern (n = 637). Models were adjusted for age, sex, past smoking, current smoking, and physical activity. Mean log triglyceride levels were significantly higher among participants in the 4th compared to the 1st quartile of the processed foods dietary pattern (β = 0.11). Mean HbA1c percent was significantly lower (β = -0.08) and mean diastolic blood pressure (DBP) mm Hg was significantly higher (β = 2.87) among participants in the 4th compared to the 1st quartile of the fruits and vegetables dietary pattern. Finally, mean log triglyceride levels and mean DBP mm Hg were significantly lower among participants in the 4th compared to the 1st quartile of the subsistence foods dietary pattern (β = -0.10 and β = -3.99 respectively).

CONCLUSIONS

We found increased CM risk, as reflected by increased triglycerides, associated with eating a greater frequency of processed foods, and reduced CM risk, as reflected by lower triglycerides and DBP, associated with eating a greater frequency of subsistence foods.

Contribution of health behaviors to the association between area-level socioeconomic status and cancer mortality

Cancer mortality is higher among residents of low-socioeconomic status (SES) areas than those of high-SES areas; however, the contribution of modifiable risk factors to this disparity is not known. We used data from 54,737 participants in the VITamins And Lifestyle (VITAL) Study, aged 50-76 with no history of cancer at baseline (2000-2002). Of these, 1488 died of cancer over an average of 7.7 years of follow-up. Data on modifiable risk factors including body mass index (BMI), physical activity, diet, alcohol, smoking and screening were taken from baseline questionnaires. We constructed a block group-level SES index using data from the 2000 United States Census and fit Cox proportional hazards models estimating the association between area-level SES and total cancer mortality with and without control for modifiable risk factors. All statistical tests are 2-sided. Cancer mortality was 77% (95% CI: 50%, 111%) higher in the lowest-SES areas compared with the highest. Modifiable risk factors accounted for 45% (95% CI: 34%, 62%) of this association. Smoking explained the greatest proportion (29%; 95% CI: 22%, 40%) of the observed association, followed by diet (11%; 95% CI: 7%, 17%), physical activity (10%; 95% CI: 7%, 16%), screening (9%; 6%, 13%), and BMI (5%; 95% CI: 1%, 10%). Results were similar in models controlling for individual education and income. The association between area-level SES and cancer mortality is partially explained by modifiable risk factors, which could suggest the appropriate targets to reduce socioeconomic disparities.

No association between blood telomere length and longitudinally assessed diet or adiposity in a young adult Filipino population

PURPOSE

Telomeres, DNA-protein structures that cap and protect chromosomes, are thought to shorten more rapidly when exposed to chronic inflammation and oxidative stress. Diet and nutritional status may be a source of inflammation and oxidative stress. However, relationships between telomere length (TL) and diet or adiposity have primarily been studied cross-sectionally among older, overweight/obese populations and yielded inconsistent results. Little is known about the relationship between diet or body composition and TL among younger, low- to normal-weight populations. It also remains unclear how cumulative exposure to a specific diet or body composition during the years of growth and development, when telomere attrition is most rapid, may be related to TL in adulthood.

METHODS

In a sample of 1459 young adult Filipinos, we assessed the relationship between blood TL at ages 20.8-22.5 and measures of BMI z-score, waist circumference, and diet collected between the ages of 8.5 and 22.5. TL was measured using monochrome multiplex quantitative PCR, and diet was measured using multiple 24-h recalls.

RESULTS

We found no associations between blood TL and any of the measures of adiposity or between blood TL and the seven dietary factors examined: processed meats, fried/grilled meats and fish, non-fried fish, coconut oil, fruits and vegetables, bread and bread products, and sugar-sweetened beverages.

CONCLUSIONS

Considering the inconsistencies in the literature and our null results, small differences in body composition and consumption of any single pro- or anti-inflammatory dietary component may not by themselves have a meaningful impact on telomere integrity, or the impact may differ across distinct ecological circumstances.

Family/friend recommendations and mammography intentions: the roles of perceived mammography norms and support

Identifying factors that increase mammography use among Latinas is an important public health priority. Latinas are more likely to report mammography intentions and use, if a family member or friend recommends that they get a mammogram. Little is known about the mechanisms underlying the relationship between social interactions and mammography intentions. Theory suggests that family/friend recommendations increase perceived mammography norms (others believe a woman should obtain a mammogram) and support (others will help her obtain a mammogram), which in turn increase mammography intentions and use. We tested these hypotheses with data from the ¡Fortaleza Latina! study, a randomized controlled trial including 539 Latinas in Washington State. Women whose family/friend recommended they get a mammogram within the last year were more likely to report mammography intentions, norms and support. Perceived mammography norms mediated the relationship between family/friend recommendations and intentions, Mediated Effect = 0.38, 95%CI [0.20, 0.61], but not support, Mediated Effect = 0.002, 95%CI [-0.07, 0.07]. Our findings suggest perceived mammography norms are a potential mechanism underlying the effect of family/friend recommendations on mammography use among Latinas. Our findings make an important contribution to theory about the associations of social interactions, perceptions and health behaviors.

Folate-mediated one-carbon metabolism genes and interactions with nutritional factors on colorectal cancer risk: Women's Health Initiative Observational Study

BACKGROUND

Investigations of folate-mediated one-carbon metabolism (FOCM) genes and gene-nutrient interactions with respect to colorectal cancer (CRC) risk are limited to candidate polymorphisms and dietary folate. This study comprehensively investigated associations between genetic variants in FOCM and CRC risk and whether the FOCM nutrient status modified these associations.

METHODS

Two hundred eighty-eight candidate and tagging single-nucleotide polymorphisms (SNPs) in 30 FOCM genes were genotyped for 821 incident CRC case-control matched pairs in the Women's Health Initiative Observational Study cohort. FOCM biomarkers (red blood cell [RBC] folate, plasma folate, pyridoxal-5'-phosphate [PLP], vitamin B12, and homocysteine) and self-reported alcohol consumption were measured at the baseline. Conditional logistic regression was implemented; effect modification was examined on the basis of known enzyme-nutrient relations.

RESULTS

Statistically significant associations were observed between CRC risk and functionally defined candidate SNPs of methylenetetrahydrofolate dehydrogenase 1 (MTHFD1; K134R), 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR; P450R), and PR domain containing 2 with ZNF domain (PRDM2; S450N) and a literature candidate SNP of thymidylate synthase (TYMS; g.676789A>T; nominal P < .05). In addition, suggestive associations were noted for tagging SNPs in cystathionine-β-synthase (CBS), dihydrofolate reductase (DHFR), DNA (cytosine-5-)-methyltransferase 3β (DNMT3B), methionine adenosyltransferase I α (MAT1A), MTHFD1, and MTRR (nominal P < .05; adjusted P, not significant). Significant interactions between nutrient biomarkers and candidate polymorphisms were observed for 1) plasma/RBC folate and folate hydrolase 1 (FOLH1), paraoxonase 1 (PON1), transcobalamin II (TCN2), DNMT1, and DNMT3B; 2) plasma PLP and TYMS TS3; 3) plasma B12 and betaine-homocysteine S-methyltransferase 2 (BHMT2); and 4) homocysteine and methylenetetrahydrofolate reductase (MTHFR) and alanyl-transfer RNA synthetase (AARS).

CONCLUSIONS

Genetic variants in FOCM genes are associated with CRC risk among postmenopausal women. FOCM nutrients continue to emerge as effect modifiers of genetic influences on CRC risk.

Psychological distress, social withdrawal, and coping following receipt of an abnormal mammogram among different ethnicities: a mediation model

PURPOSE/OBJECTIVES

To explore ethnic differences in psychological distress and social withdrawal after receiving an abnormal mammogram result and to assess if coping strategies mediate ethnic differences.

DESIGN

Descriptive correlational.

SETTING

Two urban mobile mammography units and a rural community hospital in the state of Washington.

SAMPLE

41 Latina and 41 non-Latina Caucasian (NLC) women who had received an abnormal mammogram result.

METHODS

Women completed standard sociodemographic questions, Impact of Event Scale-Revised, the social dimension of the Psychological Consequences Questionnaire, and the Brief COPE.

MAIN RESEARCH VARIABLES

Ethnicity, psychological distress, social withdrawal, and coping.

FINDINGS

Latinas experienced greater psychological distress and social withdrawal compared to NLC counterparts. Denial as a coping strategy mediated ethnic differences in psychological distress. Religious coping mediated ethnic differences in social withdrawal.

CONCLUSIONS

Larger population-based studies are necessary to understand how ethnic differences in coping strategies can influence psychological outcomes. This is an important finding that warrants additional study among women who are and are not diagnosed with breast cancer following an abnormal mammogram.

IMPLICATIONS FOR NURSING

Nurses may be able to work with Latina patients to diminish denial coping and consequent distress. Nurses may be particularly effective, given cultural values concerning strong interpersonal relationships and respect for authority figures.

Estimating pesticide exposure from dietary intake and organic food choices: the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Organophosphate pesticide (OP) exposure to the U.S. population is dominated by dietary intake. The magnitude of exposure from diet depends partly on personal decisions such as which foods to eat and whether to choose organic food. Most studies of OP exposure rely on urinary biomarkers, which are limited by short half-lives and often lack specificity to parent compounds. A reliable means of estimating long-term dietary exposure to individual OPs is needed to assess the potential relationship with adverse health effects.

OBJECTIVES

We assessed long-term dietary exposure to 14 OPs among 4,466 participants in the Multi-Ethnic Study of Atherosclerosis, and examined the influence of organic produce consumption on this exposure.

METHODS

Individual-level exposure was estimated by combining information on typical intake of specific food items with average OP residue levels on those items. In an analysis restricted to a subset of participants who reported rarely or never eating organic produce ("conventional consumers"), we assessed urinary dialkylphosphate (DAP) levels across tertiles of estimated exposure (n = 480). In a second analysis, we compared DAP levels across subgroups with differing self-reported organic produce consumption habits (n = 240).

RESULTS

Among conventional consumers, increasing tertile of estimated dietary OP exposure was associated with higher DAP concentrations (p < 0.05). DAP concentrations were also significantly lower in groups reporting more frequent consumption of organic produce (p < 0.02).

CONCLUSIONS

Long-term dietary exposure to OPs was estimated from dietary intake data, and estimates were consistent with DAP measurements. More frequent consumption of organic produce was associated with lower DAPs.

Promoting Changes in Obesogenic Behaviors: Does Coworker Social Support Play a Role?

Purpose.

To examine the association between worksite social support and changes in diet, physical activity, and body mass index (BMI).

Design.

Cohort analysis of an underlying randomized, controlled weight gain prevention worksite trial: Promoting Activity and Changes in Eating.

Setting.

The trial occurred in the greater Seattle area.

Subjects.

Baseline and follow-up data were obtained on a nested cohort of employees (n = 958–1078) from 33 small- to medium-sized worksites.

Measures.

Worksite social support, diet, physical activity, and BMI measures were assessed using a self-reported questionnaire.

Analysis.

To adjust for multilevel data and multiple time points, we used generalized estimating equations and logistic mixed models.

Results.

Higher baseline worksite social support was associated with greater changes in fruit and vegetable intake (p= .001; summary food-frequency questions).

Conclusion.

This study does not support a conclusive relationship between worksite social support and health behavior change.

Red blood cell folate and plasma folate are not associated with risk of incident colorectal cancer in the Women's Health Initiative observational study

The relationship between folate and colorectal cancer (CRC) risk is unclear. We investigated the association of two biomarkers of folate status, plasma folate and red blood cell (RBC) folate, with CRC risk using a nested case-control design in the Women's Health Initiative Observational Study. Postmenopausal women (n = 93,676) aged 50-79 years were enrolled in the Women's Health Initiative Observational Study (1993-1998). A fasting blood draw and extensive health, dietary and lifestyle data were collected upon enrollment. Through 2008, 988 incident CRC cases were reported and confirmed with medical records adjudication. Cases and controls were matched on age (± 3 years), enrollment date (± 1 year), race/ethnicity, blood draw date (± 6 months) and hysterectomy status. Plasma and RBC folate were determined by radio assay. Folate biomarker values were divided into quartiles, and conditional logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CI) for the associations of folate with total CRC, by tumor site and by stage at diagnosis. Additional analyses examined whether risks varied across time periods corresponding to the United States folic acid fortification policy: prefortification (1994-1995), perifortification (1996-1997) and postfortification (1998). ORs for overall CRC risk comparing Q4 vs. Q1 were 0.91 (95% CI 0.67-1.24) and 0.91 (95% CI 0.67-1.23) for RBC and plasma folate, respectively. There were no changes in risk attributable to food supply fortification. These results do not support an overall association of folate with CRC risk and suggest that folic acid fortification of the US food supply did not alter the associations in these postmenopausal women.

Worksite neighborhood and obesogenic behaviors: findings among employees in the Promoting Activity and Changes in Eating (PACE) trial

BACKGROUND

Understanding mechanisms linking neighborhood context to health behaviors may provide targets for increasing lifestyle intervention effectiveness. Although associations between home neighborhood and obesogenic behaviors have been studied, less is known about the role of worksite neighborhood.

PURPOSE

To evaluate associations between worksite neighborhood context at baseline (2006) and change in obesogenic behaviors of adult employees at follow-up (2007-2009) in a worksite randomized trial to prevent weight gain.

METHODS

Worksite property values were used as an indicator of worksite neighborhood SES (NSES). Worksite neighborhood built environment attributes associated with walkability were evaluated as explanatory factors in relationships among worksite NSES, diet, and physical activity behaviors of employees. Behavioral data were collected at baseline (2005-2007) and follow-up (2007-2009). Multilevel linear and logistic models were constructed adjusting for covariates and accounting for clustering within worksites. Product-of-coefficients methods were used to assess mediation. Analyses were performed after study completion (2011-2012).

RESULTS

Higher worksite NSES was associated with more walking (OR=1.16, 95% CI=1.03, 1.30, p=0.01). Higher density of residential units surrounding worksites was associated with more walking and eating five or more daily servings of fruits and vegetables, independent of worksite NSES. Residential density partially explained relationships among worksite NSES, fruit and vegetable consumption, and walking.

CONCLUSIONS

Worksite neighborhood context may influence employees' obesogenic behaviors. Furthermore, residential density around worksites could be an indicator of access to dietary and physical activity-related infrastructure in urban areas. This may be important given the popularity of worksites as venues for obesity prevention efforts.

Understanding the patient-provider communication needs and experiences of Latina and non-Latina White women following an abnormal mammogram

Latinas are more likely to delay recommended follow-up care than non-Latina White (NLW) women after an abnormal mammogram result. Ethnic differences in communication needs and experiences with health-care staff and providers may contribute to these delays as well as satisfaction with care. Nonetheless, little research has explored the aspects of communication that may contribute to patient comprehension, adherence to follow-up care, and satisfaction across ethnicity. The purpose of this exploratory, qualitative study was to identify patients' communication needs and experiences with follow-up care among Latina and NLW women who received an abnormal mammogram. We conducted 41 semi-structured interviews with 19 Latina and 22 NLW women between the ages of 40 and 74 who had received an abnormal mammogram. Communication themes indicated that women's needs and experiences concerning abnormal mammograms and follow-up care varied across ethnicity. Latinas and NLW women appeared to differ in their comprehension of abnormal results and follow-up care as a result of language barriers and health literacy. Both groups of women identified clear, empathic communication as being important in patient-provider communication; however, Latinas underscored the need for warm communicative styles, and NLW women emphasized the importance of providing more information. Women with high levels of satisfaction with patient-provider interactions appeared to have positive perspectives of subsequent screening and cancer treatment. To improve patient satisfaction and adherence to follow-up care among Latinas, educational programs are necessary to counsel health-care professionals with regard to language, health literacy, and empathic communication needs in health-care service delivery.

Estimated intake of vitamin D and its interaction with vitamin A on lung cancer risk among smokers

Data are very limited on vitamin D and lung cancer prevention in high-risk populations. The authors investigated whether estimated vitamin D intake was associated with lung cancer risk and whether effect modification by vitamin A existed among current/former heavy smokers and workers with occupational exposure to asbestos. A case-cohort study selected 749 incident lung cancers and 679 noncases from the Carotene and Retinol Efficacy Trial (CARET), 1988-2005. The active intervention was supplementation of 30 mg β-carotene + 25,000 IU retinyl palmitate/day. Baseline total intake including both diet (from food frequency questionnaire) and personal supplements (from brand names linked to the labeled potencies) was assessed. Hazard ratios (HRs) were estimated by Cox proportional hazard models. No significant association of total vitamin D intake with lung cancer was observed overall. However, total vitamin D intake ≥600 versus <200 IU/day was associated with a lower risk of non-small cell lung cancer among former smokers [HR = 0.36, 95% confidence interval (CI) = 0.13-0.96]. Total vitamin D intake ≥400 versus <400 IU/day was associated with a lower risk of total lung cancer among participants who received the CARET active intervention (HR = 0.56, 95% CI = 0.32-0.99) and among those who had total vitamin A intake ≥1,500 µg/day retinol activity equivalent (RAE; HR = 0.46, 95% CI = 0.23-0.91). The beneficial associations were attenuated among those who did not receive the CARET active intervention or who had total vitamin A intake <1,500 µg/day RAE (p-interaction = 0.02 for current smokers). Our observation suggests that vitamin A may assist vitamin D in preventing lung cancer among smokers.

Plasma choline metabolites and colorectal cancer risk in the Women's Health Initiative Observational Study

Few studies have examined associations between plasma choline metabolites and risk of colorectal cancer. Therefore, we investigated associations between plasma biomarkers of choline metabolism [choline, betaine, dimethylglycine, and trimethylamine N-oxide (TMAO)] and colorectal cancer risk among postmenopausal women in a case-control study nested within the Women's Health Initiative Observational Study. We selected 835 matched case-control pairs, and cases were further stratified by tumor site (proximal, distal, or rectal) and stage (local/regional or metastatic). Colorectal cancer was assessed by self-report and confirmed by medical records over the mean of 5.2 years of follow-up. Baseline plasma choline metabolites were measured by LC/MS-MS. In multivariable-adjusted conditional logistic regression models, plasma choline tended to be positively associated with rectal cancer risk [OR (95% confidence interval, CI)(highest vs. lowest quartile) = 2.44 (0.93-6.40); P trend = 0.08], whereas plasma betaine was inversely associated with colorectal cancer overall [0.68 (0.47-0.99); P trend = 0.01] and with local/regional tumors [0.64 (0.42-0.99); P trend = 0.009]. Notably, the plasma betaine:choline ratio was inversely associated with colorectal cancer overall [0.56 (0.39-0.82); P trend = 0.004] as well as with proximal [0.66 (0.41-1.06); P trend = 0.049], rectal [0.27 (0.10-0.78); P trend = 0.02], and local/regional [0.50 (0.33-0.76); P trend = 0.001] tumors. Finally, plasma TMAO, an oxidative derivative of choline produced by intestinal bacteria, was positively associated with rectal cancer [3.38 (1.25-9.16); P trend = 0.02] and with overall colorectal cancer risk among women with lower (vs. higher) plasma vitamin B12 levels (P interaction = 0.003). Collectively, these data suggest that alterations in choline metabolism, which may arise early in disease development, may be associated with higher risk of colorectal cancer. The positive association between plasma TMAO and colorectal cancer risk is consistent with an involvement of the gut microbiome in colorectal cancer pathogenesis.

Using a biokinetic model to quantify and optimize cortisol measurements for acute and chronic environmental stress exposure during pregnancy

To fully understand the potentially harmful effects of prenatal stress exposure impacts, it is necessary to quantify long-term and episodic stress exposure during pregnancy. There is a strong body of research relating psychological stress to elevated cortisol levels in biomarkers. Recently, maternal hair has been used to measure cortisol levels, and provides the unique opportunity to assess stress exposure throughout gestation. Understanding how cortisol in the hair is related to more common biomarkers, such as, blood, saliva and urine is currently lacking. Therefore, we developed a biokinetic model to quantify the relationships between hair, blood, saliva and urine cortisol concentrations using published literature values. Hair concentrations were used to retrospectively predict peaks in blood and saliva concentrations over days and months. Simulations showed realistic values in all compartments when results were compared with published literature. We also showed that the significant variability of cortisol in blood leads to a weak relationship between long-term and episodic measurements of stress. To our knowledge, this is the first integrative biokinetic cortisol model for blood, urine, hair and saliva. As such, it makes an important contribution to our understanding of cortisol as a biomarker and will be useful for future epidemiological studies.

Life's Simple 7 and incidence of diabetes among American Indians: the Strong Heart Family Study

OBJECTIVE

The American Heart Association's recommendations for optimal health, summarized in Life's Simple 7, have been associated with reduced risk of cardiovascular disease (CVD)-related end points, but no studies have examined the association of these goals with incident type 2 diabetes, which is associated with high risk for CVD. The purpose of this analysis was to examine the associations of Life's Simple 7 goals with incident diabetes among American Indians, a population at high risk of cardiometabolic diseases.

RESEARCH DESIGN AND METHODS

Strong Heart Family Study participants without diabetes (n = 1,639) at baseline and who participated in a follow-up examination were included in the analysis. Risk scores ranging from 0 to 7 were created using physical activity, diet, BMI, smoking, blood pressure, fasting glucose, and cholesterol metrics in accordance with Life's Simple 7 goals. Diabetes was defined using 2003 American Diabetes Association criteria, including use of insulin or oral antidiabetes medication or a follow-up fasting plasma glucose level ≥126 mg/dL. Generalized estimating equations were used to examine the association of risk scores with incident diabetes.

RESULTS

During a mean 5-year follow-up (range 4-8 years), we identified 210 cases of incident type 2 diabetes. Compared with participants who achieved 0-1 goals, those who achieved 2-3 or 4+ goals had lower odds of diabetes, with odds ratios = 0.40 (95% CI 0.29-0.56) and 0.11 (95% CI 0.05-0.21), respectively.

CONCLUSIONS

The adoption of as few as two or three Life's Simple 7 goals is associated with a lower risk of diabetes.

Vitamin D intake determines vitamin d status of postmenopausal women, particularly those with limited sun exposure

Few detailed data are available on the wide range of determinants of vitamin D status among postmenopausal women, and it is also unclear whether there may be undiscovered determinants. The objective of this study was to comprehensively evaluate determinants of serum 25-hydroxyvitamin D [25(OH)D] concentrations in a large cohort of postmenopausal women. Data from a subset of the Women's Health Initiative Observational Study were analyzed (50-79 y; n = 3345). Information on diet, lifestyle behaviors, secondhand smoke, use of dietary supplements and medication, chronic diseases, and anthropometry was collected at baseline (1993-1998) and on sun exposure at year 4 follow-up. Linear regression was performed to estimate regression coefficients (β). Significant determinants were total vitamin D intake (food plus supplements per 100 IU/d, β = 2.08), years of supplemental vitamin D use (β = 0.15), total fat intake (grams per day, β = -0.03), smoking status (β = -2.64, current vs. never), regional solar irradiance (β = 6.26, 475-500 vs. 300-325 Langleys), daylight time spent outdoors in summer (β = 5.15, >2 h vs. <30 min/d), recreational physical activity (metabolic equivalent task per hour per week, β = 0.13), waist circumference (centimeters, β = -0.26), and race/ethnicity (β = -11.94, black vs. white). Total vitamin D intake (partial R(2) = 0.09) explained the most variance in serum 25(OH)D concentrations (total R(2) = 0.29). The association between total vitamin D intake and serum 25(OH)D concentrations was stronger among participants who spent less rather than more daylight time outdoors in summer (P-interaction = 0.026). History and medications for hypertension, hyperlipidemia, and type 2 diabetes and secondhand smoke exposure were not associated with serum 25(OH)D. In conclusion, dietary factors and sun exposure remain important determinants of vitamin D status in postmenopausal women. Vitamin D intake should be emphasized for those with limited sun exposure.