Calibration of the dietary questionnaire for a multiethnic cohort in Hawaii and Los Angeles

Circulating microRNAs and alcohol consumption in the multiethnic cohort study

Excessive alcohol consumption is a significant public health concern and contributes to liver diseases and cancer. Modifiable lifestyle factors including alcohol consumption can influence circulating microRNAs (miRNAs), which are increasingly used as biomarkers for early disease detection. Yet limited studies have identified miRNAs associated with alcohol intake, particularly in multiethnic populations. We aimed to assess the association of alcohol consumption and circulating miRNAs in the Multiethnic Cohort Study. Participants (N = 917) had alcohol consumption data collected at baseline and miRNA data collected at follow-up. Negative binomial models were used to assess the association between alcohol consumption (continuous and categorical [nondrinkers: 0 g of ethanol/day; light drinkers: <28 g of ethanol/day for men and <14 g of ethanol/day for women; and heavy drinkers: ≥28 g of ethanol/day for men and ≥14 g of ethanol/day for women]) and miRNAs. Stratified analyses also examined categories by sex, race/ethnicity, smoking status, and body mass index. Overall, there were 52% non-drinkers, 37 % light drinkers, and 11 % were heavy drinkers. We did not detect an association of miRNAs with alcohol intake in continuous models after correcting for multiple comparisons. However, we did find an inverse association for light drinkers [incidence rate ratio (IRR) = 0.59, p = 8.21E-04] and heavy drinkers (IRR = 0.44, p = 1.47E-03) compared to nondrinkers for miR-451a. Additionally, miR-320e (IRR = 0.63, p = 1.61E-03) had an inverse association with alcohol intake for light drinkers compared to nondrinkers. Subgroup analysis also suggested there were differences by subgroups, underscoring that miRNAs used to detect chronic diseases may be subgroup specific. When stratified by case-control status, we found that among controls both light and heavy drinkers were associated with miR-451a. We identified an association for light and heavy drinkers with miR-451a and mir-320e, miRNAs associated with cancers and liver diseases, in comparison to nondrinkers.

Inflammatory and insulinemic dietary and lifestyle patterns and incidence of endometrial cancer: the multiethnic cohort

BACKGROUND

The incidence of endometrial cancer (EC) is increasing, particularly among racial and ethnic minority groups. Obesity is an established EC risk factor, and obesity-related inflammation and hyperinsulinemia may play an important role in EC etiology.

OBJECTIVES

We examined the association of 5 empirical hypothesis-oriented dietary and lifestyle indices, which assess the inflammatory and insulinemic potentials of diet and lifestyle, with risk of EC in ethnically diverse females.

METHODS

We included 60,441 female participants from the multiethnic cohort study, a cohort-based in the United States, who were African American, Japanese American, Latino, Native Hawaiian, or White, aged 45-75 y at baseline in 1993-1996. Using a quantitative food frequency questionnaire at baseline, we computed the empirical dietary inflammatory pattern (EDIP), empirical dietary index for hyperinsulinemia (EDIH), empirical lifestyle index for hyperinsulinemia (ELIH), empirical dietary index for insulin resistance (EDIR), and empirical lifestyle index for insulin resistance (ELIR). Multivariable Cox models adjusting for known risk factors for EC were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between each index (using quintiles) and EC risk.

RESULTS

We identified 1328 incident EC cases with a median follow-up of 25.2 y (IQR = 7.4 y). Females with higher ELIH had an increased risk of EC (HRQ5vsQ1 = 2.58, 95% CI: 2.16, 3.09; Ptrend < 0.01). Similarly, higher ELIR was significantly associated with an increased risk of EC (HRQ5vsQ1 = 2.89, 95% CI: 2.37, 3.53; Ptrend < 0.01). EDIP, EDIH, and EDIR were not associated with EC risk. Increased risk of EC with ELIH (all Ptrend < 0.01) and ELIR (all Ptrend < 0.01) was found in all racial and ethnic groups.

CONCLUSIONS

In this ethnically diverse cohort, lifestyle patterns with higher insulinemic potential were associated with an increased risk of EC. Lifestyle changes that include more physical activity and achieving a healthy body weight, in addition to reducing insulinemic and diets, may lower EC risk.

Race and Ethnicity, Lifestyle, Diet, and Survival in Patients With Prostate Cancer

Importance

Prostate cancer (PCa) remains a leading cause of cancer-related death among men in the US.

Objective

To evaluate the association of healthy lifestyle and dietary behaviors with survival after a nonmetastatic PCa diagnosis in a multiethnic population.

Design, Setting, and Participants

This prospective cohort study was conducted among men aged 45 to 75 years enrolled between 1993 and 1996 in the Multiethnic Cohort study. Participants with nonmetastatic PCa completed a questionnaire after diagnosis (2003-2008) and were followed up until death or loss to follow-up. Data were analyzed from January 10, 2023, to May 20, 2024.

Exposures

Lifestyle and dietary patterns were assessed after diagnosis using 3 PCa behavior scores and 13 dietary indices (4 prioritized scores: the Healthy Eating Index-2015, Healthful Plant-Based Diet Index, Dietary Inflammatory Index, and Empirical Dietary Index for Hyperinsulinemia).

Main Outcomes and Measures

Cox proportional hazards models were used to evaluate multivariable-adjusted associations of each PCa behavior score with all-cause, cardiovascular disease (CVD), and PCa-specific mortality.

Results

A total of 2603 men with nonmetastatic PCa (mean [SD] age, 69.6 [7.1] years) were followed up, and 1346 deaths were documented, including 356 (24.6%) from CVD and 197 (14.6%) from PCa. The median (IQR) follow-up was 10.9 (IQR, 6.8-12.7) years from questionnaire return and 14.5 (IQR, 11.8-18.0) years from diagnosis. The 2021 PCa Behavior Score was associated with reduced risks of all-cause (hazard ratio [HR] per point, 0.69; 95% CI, 0.63-0.77) and CVD-related (HR, 0.67; 95% CI, 0.56-0.79) mortality. This score was also associated with a lower risk of PCa-specific mortality among African American men (HR, 0.46; 95% CI, 0.24-0.88) but not in the other racial and ethnic groups. Comparing quintile 5 (highest score) with 1 (lowest score), the Empirical Dietary Index for Hyperinsulinemia was positively associated with all-cause (HR, 1.37; 95% CI, 1.02-1.84) and CVD-related (HR, 1.96; 95% CI, 1.15-3.33) mortality, whereas the Healthful Plant-Based Diet Index was associated with a reduced risk of all-cause (HR, 0.75; 95% CI, 0.58-0.97); findings for CVD-related mortality were not statistically significant (HR, 0.67; 95% CI, 0.44-1.03). No associations were found between lifestyle or dietary patterns and PCa mortality.

Conclusions and Relevance

In this multiethnic cohort of patients with nonmetastatic PCa, healthier lifestyles were associated with improved overall survival but not with PCa-specific survival. Given the predominance of non-PCa-specific deaths, these findings support the need for health behavior counseling to treat comorbidities in men with PCa.

Factors related to mean corpuscular volume in HFE p.C282Y homozygotes

Introduction

The aim of this study was to define the relationships between factors other than transferrin saturation (TS) to mean corpuscular volume (MCV) and macrocytosis (MCV > 100 fL) in HFE p.C282Y (rs1800562) homozygotes.

Methods

We studied white post-screening participants with p.C282Y homozygosity who did not have anemia, report cirrhosis or pregnancy, or use medications that increase MCV. We analyzed relations of MCV and macrocytosis with age, sex, diabetes reports, daily alcohol consumption, swollen or tender 2nd/3rd metacarpophalangeal (MCP) joints, TS, and serum ferritin (SF).

Results

There were 257 participants (110 men and 147 women). Median alcohol consumption, median TS, median SF, and macrocytosis prevalence were significantly greater in men. Relative risk of macrocytosis in men was 2.81. In men and women, there were significant positive Pearson's correlations of MCV versus age and Spearman's correlations of MCV versus alcohol consumption and TS. Mean MCV and macrocytosis prevalence were significantly greater in participants with than without swollen or tender 2nd/3rd MCP joints. Linear regression on MCV revealed positive associations: age (p < 0.0001), alcohol consumption (p = 0.0007), and TS (p < 0.0001). Logistic regression on macrocytosis revealed an odds ratio for age of 1.04 (95% confidence interval: 1.00, 1.07).

Conclusions

MCV in HFE p.C282Y homozygotes is positively related to age, daily alcohol consumption, TS, and swollen or tender 2nd/3rd MCP joints.

Sleep Duration, Dietary Inflammatory Potential, and Obesity in Relation to Colorectal Cancer Incidence in the Multiethnic Cohort

BACKGROUND/OBJECTIVES

Colorectal cancer (CRC) is a leading cause of cancer-related morbidity and mortality worldwide. Sleep duration, diet, and obesity have each been identified as modifiable risk factors linked to CRC. However, their joint effect on CRC incidence is underexplored. This study investigated the association between sleep duration and CRC incidence and explored the joint effects of sleep duration, a pro-inflammatory diet, and obesity on CRC incidence in the Multiethnic Cohort (MEC).

METHODS

This prospective cohort study analyzed 193,027 participants from Hawaii and California enrolled in the MEC between 1993 and 1996. Sleep duration was self-reported and categorized as short (≤6 h), normal (7-8 h), or long (≥9 h). Diet was self-reported via FFQ and inflammatory potential was assessed using the energy-adjusted Dietary Inflammatory Index (E-DII). CRC cases were identified via cancer registries. Cox proportional hazards models estimated the hazard ratios (HRs) for CRC risk.

RESULTS

After 23.8 years of follow-up, 5825 CRC cases were identified. A pro-inflammatory diet combined with suboptimal sleep increased CRC risk by 12% (short sleep duration, aHR: 1.12; 95% CI: 1.02-1.24) and 22% (long sleep duration, aHR: 1.22, 95% CI: 1.05-1.43). Furthermore, long sleep duration was associated with a 10% increase in CRC risk (aHR: 1.10; 95% CI: 1.01-1.22) compared with normal sleep, while short sleep showed no significant association overall. Obese individuals with short or long sleep had significantly higher CRC risk (short sleep aHR: 1.35; 95% CI: 1.21-1.51; long sleep aHR: 1.36; 95% CI: 1.14-1.64) compared with non-obese individuals with corresponding sleep durations.

CONCLUSIONS

Long sleep duration and a combination of suboptimal sleep duration and a pro-inflammatory dietary pattern or obesity amplifies the risk.

Dietary Fiber Intake and Risk of Advanced and Aggressive Forms of Prostate Cancer: A Pooled Analysis of 15 Prospective Cohort Studies

BACKGROUND

Evidence of an association between dietary fiber intake and risk of advanced and aggressive forms of prostate cancer (PC) and PC mortality is limited.

OBJECTIVE

The aim of this study was to examine associations between intakes of dietary fiber overall and by food source and risk of advanced and aggressive forms of PC.

DESIGN

The study design was a pooled analysis of the primary data from 15 cohorts in 3 continents. Baseline dietary fiber intake was assessed using a validated food frequency questionnaire or diet history in each study.

PARTICIPANTS/SETTING

There were 842 149 men followed for up to 9 to 22 years between 1985 and 2009 across studies.

MAIN OUTCOME MEASURES

The primary outcome measures were advanced (stage T4, N1, or M1 or PC mortality), advanced restricted (excluded men with missing stage and those with localized PC who died of PC), and high-grade PC (Gleason score ≥8 or poorly differentiated/undifferentiated) and PC mortality.

STATISTICAL ANALYSIS PERFORMED

Study-specific multivariable hazard ratios (MVHR) were calculated using Cox proportional hazards regression and pooled using random effects models.

RESULTS

Intake of dietary fiber overall, from fruits, and from vegetables was not associated with risk of advanced (n = 4863), advanced restricted (n = 2978), or high-grade PC (n = 9673) or PC mortality (n = 3097). Dietary fiber intake from grains was inversely associated with advanced PC (comparing the highest vs lowest quintile, MVHR 0.84; 95% CI 0.76-0.93), advanced restricted PC (MVHR 0.85; 95% CI 0.74-0.97), and PC mortality (MVHR 0.78; 95% CI 0.68-0.89); statistically significant trends were noted for each of these associations (P ≤ .03), and a null association was observed for high-grade PC for the same comparison (MVHR 1.00; 95% CI 0.93-1.07). The comparable results were 1.06 (95% CI 1.01-1.10; P value, test for trend = .002) for localized PC (n = 35,199) and 1.05 (95% CI 0.99-1.11; P value, test for trend = .04) for low/intermediate grade PC (n = 34 366).

CONCLUSIONS

Weak nonsignificant associations were observed between total dietary fiber intake and risk of advanced forms of PC, high-grade PC, and PC mortality. High dietary fiber intake from grains was associated with a modestly lower risk of advanced forms of PC and PC mortality.

Investigating Causal Associations of Diet Compositions with the Risk of Lung Cancer

OBJECTIVE

This study aimed to investigate the causal relationship between diet compositions and lung cancer (LC) risk.

METHODS

A two-sample Mendelian randomization (MR) analysis was performed to assess the causal relationship between diet and LC risk, including three LC subtypes. Instrumental variables (IVs) for three diet compositions were selected from genome-wide association studies (GWAS). Summary statistics for LC and its subtypes came from the largest meta-analysis. The inverse-variance weighted (IVW) method was used as the main MR analysis, with sensitivity analyses to ensure result robustness. Then, we conducted an observational study using data from National Health and Nutrition Examination Survey (NHANES) to verify the relationship.

RESULTS

Our results showed significant evidence that fat intake was correlated with the lower risk of lung adenocarcinoma. There were also suggestive correlations between fat intake and overall LC. However, no significant associations were found between other macronutrients and LC risk. NHANES data further showed that higher polyunsaturated fatty acid (PUFA) intake was linked to better outcomes in LC patients.

CONCLUSION

PUFA intake may have a protective effect against LC. Adjusting dietary proportions could potentially help in the primary prevention of LC.

The EAT-Lancet Diet Index Is Associated with Lower Obesity and Incidence of Type 2 Diabetes in the Multiethnic Cohort

BACKGROUND

The EAT-Lancet Commission has developed dietary recommendations, named the EAT-Lancet diet, to promote healthy nutrition and sustainable food production worldwide.

OBJECTIVES

We developed an adapted score for the EAT-Lancet diet for participants of the Multiethnic Cohort (MEC) Study and its relation with incidence of obesity and type 2 diabetes (T2D).

METHODS

The MEC includes 5 ethnic groups followed since 1993-1996. Anthropometric characteristics and dietary intake were assessed by questionnaire at cohort entry (Qx1) and 10 y later (Qx3). To create the EAT-Lancet index (range: 0-48 points), a 3-point scoring system for 16 food groups standardized to 2500 kcal/d was applied. T2D cases were identified through repeated self-reports and administrative data. In a prospective design, obesity at Qx3 and T2D incidence were evaluated using Cox regression to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) while adjusting for relevant covariates.

RESULTS

Among 193,379 MEC participants, the overall mean of the EAT-Lancet index score was 25 ± 4 points and 46,140 new T2D cases were identified. Higher adjusted means were observed in females than males, in participants of Japanese American and Native Hawaiian ancestry, and in those with healthy weight than overweight or obese. Obesity was lower in cohort members with higher EAT-Lancet scores (HR: 0.76; 95% CI: 0.73, 0.79 for tertile 3 compared with 1). Although T2D incidence was 10% lower among participants in the highest (27-42 points) compared with the lowest (9-23 points) EAT-Lancet index tertile (HR: 0.90; 95% CI: 0.88, 0.92), the association was attenuated after BMI adjustment (HR: 0.97; 95% CI: 0.94, 0.99). This inverse association with T2D was restricted to African American and European American participants.

CONCLUSIONS

These findings support the hypothesis that adherence to the EAT-Lancet diet is related to a lower risk of obesity, which may be partially responsible for the small reduction in T2D incidence.

Effects of Dietary Quality on Vaginal Microbiome Composition Throughout Pregnancy in a Multi-Ethnic Cohort

Background: Vaginal Lactobacillus predominance is associated with improved vaginal health and reduced pregnancy complications. Little is known about how dietary quality may improve vaginal microbial composition or about dietary interventions that may promote Lactobacillus abundance. To understand the host factors affecting vaginal microbiota during pregnancy in a multi-ethnic cohort in Hawai`i. We hypothesize that better diet quality improves vaginal microbial composition, as represented by Lactobacillus abundance and depletion of anaerobic organisms. Methods: We compared comprehensive diet quality, as measured by the Healthy Eating Index-2015 (HEI-2015), to taxonomic classifications of bacteria present within the vagina. Participants of the four predominant ethnic groups in Hawai'i (Japanese, Filipino, Non-Hispanic White and Native Hawaiian) completed Quantitative Food Frequency Questionnaires (QFFQs) and collected vaginal swabs during each trimester. 16s rRNA amplicon sequencing (V2-V9 regions) was performed on vaginal samples. HEI-2015 scores and macro- and micronutrient intake were compared with the predominant species present using the Mann-Whitney-U test, PERMANOVA, and the Pearson correlation coefficient. A mixed-effects logistics regression model was used to predict the depletion of Lactobacillus species while accounting for confounding demographic factors. Results: Matched, longitudinal data for 40 participants demonstrated three predominant Lactobacillus species: L. crispatus, L. iners, and L. gasseri, with another subset of samples with anaerobic abundance. (Primarily, Atopobium vaginae, Prevotella, and Gardnerella vaginalis.) Non-Hispanic White participants had lower amounts of Lactobacillus iners compared to other racial and ethnic groups. HEI scores correlated with the chao index and observed species number primarily in the first trimester (r = 0.25, p < 0.05). Greater carbohydrate intake was associated with a higher abundance of L. crispatus, while lower carbohydrate intake trended towards more L. iners (0.056) and anaerobic species. Conclusions: Increased carbohydrate consumption and improved diet quality may be associated with beneficial vaginal microbial composition in pregnancy.

Breast, Colorectal, and Prostate Cancer Incidence among Filipino Americans by Generational Status in the Multiethnic Cohort Study

BACKGROUND

Filipino Americans constitute 12% and 4% of the respective populations of Hawaii and California, with a large proportion of immigrants experiencing increasing cancer rates. This study investigated the incidence of colorectal, breast, and prostate cancers by generational status in the Multiethnic Cohort.

METHODS

We analyzed 10,495 Filipino Multiethnic Cohort first-, second-, and third-generation participants, in which 26.8% were of mixed race and ethnicity. Linkage to statewide cancer registries identified 375 breast, 249 colorectal, and 436 prostate cancer incident cases. Cox models were used to calculate HRs and 95% confidence intervals (CI) for the association between generational status and cancer incidence. Models were adjusted for age at cohort entry and cancer-specific covariates that were chosen based on stepwise regression.

RESULTS

Compared with the first generation, colorectal cancer showed a significantly higher incidence in the second and third generations with respective HRs of 1.43 (95% CI, 1.04, 1.98) and 1.76 (95% CI, 1.29, 2.38). This association was attenuated after adjustment for relevant covariates. Breast cancer incidence was elevated in the third versus first generation (HR = 1.29; 95% CI, 1.01, 1.63) even in the fully adjusted model, whereas little difference was observed for prostate cancer.

CONCLUSIONS

In this prospective study, we found differences in incidence by generational status, specifically colorectal cancer among men and female breast cancer.

IMPACT

Understanding behavioral changes due to acculturation is warranted to mitigate cancer risks in migrant populations.

Consumption of different types of meat and the risk of chronic limb-threatening ischemia: the Singapore Chinese Health Study

BACKGROUND

Although red meat consumption has been associated with risk of atherosclerotic coronary artery disease and stroke, no prospective study has examined this with the risk of chronic limb-threatening ischemia (CLTI).

METHODS

In a prospective study of 63,257 Chinese in Singapore, who were aged 45-74 years old at recruitment, diet was assessed via a validated semi-quantitative food frequency questionnaire. Incident CLTI cases were ascertained via linkage with nationwide hospital records for lower extremity amputation or angioplasty for peripheral arterial disease. Multivariable Cox models were used to examine associations between quartiles of meat intake and CLTI risk.

RESULTS

After a mean follow-up of 18.8 years, there were 1069 cases of CLTI. Higher intake of red meat intake was associated with increased risk of CLTI in a stepwise manner. Comparing extreme quartiles of red meat intake, the hazard ratio (HR) for the association with CLTI risk was 1.24 [95% confidence interval (CI) = 1.03-1.49; P-trend = 0.02]. In stratified analysis, red meat intake had a stronger association with CLTI risk among those without diabetes [HR (95% CI) comparing extreme quartiles = 1.41 (1.10-1.80); P-trend = 0.03] than among those with diabetes at baseline [HR (95% CI) comparing extreme quartiles = 1.04 (0.79-1.38); P-trend = 0.05] (P-interaction = 0.03). Otherwise, the associations were not different by sex, BMI, smoking status, hypertension, alcohol consumption, or history of cardiovascular diseases. Using a theoretical model in substitution analysis that substituted three servings per week of red meat with poultry or fish/shellfish, the relative risk of CLTI was reduced by 13-14%.

CONCLUSIONS

Consumption of red meat was associated with higher CLTI risk in this Asian cohort. Substituting red meat with poultry or fish/shellfish may reduce this risk.

Intake of Sugar and Food Sources of Sugar and Colorectal Cancer Risk in the Multiethnic Cohort Study

BACKGROUND

The influence of sugar intake on the risk of colorectal cancer (CRC) remains controversial, and there is a need to investigate the heterogeneity of effects among racial and ethnic groups.

OBJECTIVES

To examine the association of intake of simple sugars and their food sources with CRC risk according to race/ethnicity in a multiethnic cohort study.

METHODS

We analyzed data from 192,651 participants who participated in the Multiethnic Cohort Study comprising African American, Japanese American, Latino, Native Hawaiian, and White older adults living in Hawaii and California with an average follow-up of 19 y. Intakes of total and specific types of sugars and sugary foods were estimated from a quantitative food frequency questionnaire completed by the participants in 1993-1996. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for CRC risk according to quintiles (Q) of sugar and food intakes using Cox models adjusted for potential confounders.

RESULTS

As of December 2017, 4403 incident CRC cases were identified. Among all participants, multivariable-adjusted CRC HRs for Q2, Q3, Q4, and Q5 compared with Q1 for total sugars were 1.03 (95% CI: 0.94, 1.13), 1.05 (95% CI: 0.96, 1.16), 1.12 (95% CI: 1.01, 1.24), and 1.13 (95% CI: 1.01, 1.27), respectively. A similar positive association was observed for total fructose, glucose, fructose, and maltose but not for added sugars and sugary foods. The increased risk appeared to be limited to colon cancer and to be strongest among younger participants (i.e., 45-54 y at baseline); an association with CRC was observed for sugar-sweetened beverages in the latter group. Among racial and ethnic groups, increased risk of CRC was most apparent in Latinos.

CONCLUSIONS

In this diverse cohort, intakes of total sugar, total fructose, glucose, fructose, and maltose were associated with an increased risk of CRC, and the association was strongest for colon cancer, younger participants, and Latinos.

The Association of Alcohol Outlet Density With Alcohol Intake: The Multiethnic Cohort

OBJECTIVE

Neighborhood characteristics have been shown to influence lifestyle behaviors. Here we characterized alcohol outlet density in Los Angeles County, CA, and Hawaii and assessed the association of alcohol outlet density with self-reported alcohol intake in the Multiethnic Cohort.

METHOD

Participants (n = 178,977) had their addresses geocoded at cohort entry (1993-1996) and appended to block group-level alcohol outlet densities (on- and off-premises). Multinomial logistic regression was performed to assess the association between self-reported alcohol intake and on- and off-premise alcohol outlet densities by each state. Stratified analysis was conducted by sex, race, and ethnicity.

RESULTS

Overall, we did not find associations between alcohol outlet density and self-reported alcohol intake in Los Angeles County, but we found that on-premise alcohol outlets were associated with 59% (odds ratio [OR] = 1.59, 95% CI [1.29, 1.96]) increased odds of consuming more than two drinks per day in Hawaii. Women living in neighborhoods with a high density of on-premise alcohol outlets (Los Angeles County: OR = 1.15, 95% CI [0.95, 1.40]; Hawaii: OR = 2.07, 95% CI [1.43, 3.01]) had an increased odds of more than two drinks per day.

CONCLUSIONS

This study suggests that neighborhood factors are associated with individual-level behaviors and that multilevel interventions may be needed.

Diet Quality and Risk of Bladder Cancer in the Multiethnic Cohort Study

This study analyzed the overall quality of the diet using predefined indices, including the Healthy Eating Index-2015 (HEI-2015), the Alternative Healthy Eating Index-2010 (AHEI-2010), the alternate Mediterranean Diet (aMED) score, the Dietary Approaches to Stop Hypertension (DASH) score, and the Dietary Inflammatory Index (DII®), to explore their association with the risk of bladder cancer in the Multiethnic Cohort Study. Data were taken from 186,979 African American, Japanese American, Latino, Native Hawaiian, and non-Hispanic White participants aged 45-75 years, with 1152 incident cases of invasive bladder cancer during a mean follow-up period of 19.2 ± 6.6 years. Cox models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) with comprehensive adjustment for smoking. Comparing the highest vs. lowest diet quality score quintile, HRs (95% CIs) in men was 1.08 (0.86-1.36) for HEI-2015, 1.05 (0.84-1.30) for AHEI-2010, 1.01 (0.80-1.27) for aMED, 1.13 (0.90-1.41) for DASH, and 0.96 (0.76-1.21) for DII®, whereas the corresponding HRs for women were 0.75 (0.53-1.07), 0.64 (0.45-0.92), 0.60 (0.40-0.88), 0.66 (0.46-0.95), and 0.63 (0.43-0.90) with all p values for trend <0.05. The inverse association found in women did not vary by smoking status or race and ethnicity. Our findings suggest that adopting high-quality diets may reduce the risk of invasive bladder cancer among women in a multiethnic population.

Diet quality predicts hypertensive disorders of pregnancy in Asian and Pacific Islander Cohort

Background: There is limited data on diet quality during pregnancy and its impact on hypertensive disorders of pregnancy (HDP). Aim: Examine the association with diet quality and development of HDP in an Asian and Pacific Islander Cohort Methods: Pregnant women from the 4 largest ethnic groups in Hawai'i were recruited for participation. Participants completed a food frequency questionnaire during each trimester. Adherence to three diet quality indices (DQIs) were scored-The Healthy Eating Index (HEI), The Alternate Mediterranean Diet score (aMED), and the Dietary approaches to Stop Hypertension (DASH) score. Mean scores were compared among those who did and did not develop HDP. Logistic Regression models were used to examine the association between diet quality and HDP accounting for confounders (age, parity, obesity, ethnicity, gestational weight gain). Results: Among 55 participants with complete follow-up, there was a high incidence of HDP (23%). There was no significant change of DQIs over time. Non-Hispanic White participants had higher DQIs than Filipinas, Japanese, or Native Hawaiians (not statistically significant). Across gestation, participants who did not have HDP had better diet quality than those who did. Logistic regression showed that HEI and DASH indices are predictive of HDP development, with the high DASH diet score having the greatest reduced odds. Every point higher of DASH diet score portended approximately 30% reduced odds of developing HDP. Conclusions: The DASH diet had the strongest association with reduced odds of HDP, but better diet quality in any of the indices was also predictive.

Plant-based dietary patterns and mortality from all causes, cardiovascular disease, and cancer: The Multiethnic Cohort Study

BACKGROUND & AIMS

Plant-based dietary patterns have been associated with lower risk of cardiovascular disease (CVD), some cancers, and related mortality in U.S.

POPULATIONS

However, the quality of plant foods has rarely been considered in the association between plant-based diets and mortality, especially in a population with various racial and ethnic backgrounds. We investigated whether the adherence to plant-based dietary patterns and the healthiness of plant foods are associated with mortality from all causes, CVD, and cancer and evaluated how the association varies by race and ethnicity.

METHODS

A total of 144,729 African American, Japanese American, Latino, Native Hawaiian, and White men and women who participated in the Multiethnic Cohort Study (1993-2019) were included. Cox models were used to estimate HR and 95% CI of mortality from all causes, CVD, and cancer across quintiles of three plant-based diet scores: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI).

RESULTS

Over an average 21 years of follow-up, we identified 65,087 deaths, including 18,663 from CVD and 16,171 from cancer. Comparing the highest versus lowest quintiles, greater scores of PDI and hPDI were associated with a lower risk of all-cause mortality in both men (HR = 0.85, 95% CI: 0.82-0.89 for PDI; HR = 0.88, 95% CI: 0.85-0.91 for hPDI; both P for trend <0.0001) and women (HR = 0.89, 95% CI: 0.86-0.93 for PDI; HR = 0.86, 95% CI: 0.83-0.89 for hPDI; both P for trend <0.0001). An increased risk of all-cause mortality with uPDI was observed only in women (HR = 1.11, 95% CI: 1.07-1.15, P for trend <0.0001; P for heterogeneity by sex = 0.019). A similar trend was shown for CVD mortality with a significant increase in risk with uPDI for both men and women. PDI was associated with a lower risk of cancer mortality in men (HR = 0.86, 95% CI: 0.80-0.92, P for trend <0.0001), while neither hPDI nor uPDI was associated in either sex. Compared with the other racial and ethnic groups within each sex, the association of uPDI with all-cause mortality was stronger in White men (P for heterogeneity by race and ethnicity = 0.009) and weaker in Latino women (P for heterogeneity = 0.002).

CONCLUSION

A healthy plant-based dietary pattern emphasizing the quality of plant foods was associated with a lower risk of all-cause and CVD mortality in both men and women, although the magnitude of the associations varied across racial and ethnic groups.

The association of a healthy lifestyle index and imaging-based body fat distribution with glycemic status and Type 2 diabetes in the Multi Ethnic Cohort: a cross-sectional analysis

INTRODUCTION

As several behaviors captured by the Lifestyle Risk Factor Index (LSRI) are protective against Type 2 diabetes (T2D) and may affect body fat distribution, we examined its relation with both outcomes.

METHODS

In a subset of the Multiethnic Cohort, participants from five ethnic groups (60-77 years) were assigned LSRI scores (one point each for consuming <1 (women)/<2 (men) alcoholic drinks/day, ≥1.5 physical activity hours/week, not smoking, and adhering to ≥3/7 dietary recommendations). All participants completed an extensive Quantitative Food Frequency Questionnaire to allow estimation of adherence to intake recommendations for fruits, vegetables, refined and whole grains, fish, processed and non-processed meat. Glycemic/T2D status was classified according to self-reports and fasting glucose. We estimated prevalence odds ratios (POR) of LSRI with glycemic/T2D status and DXA- and MRI-based body fat distribution using logistic regression.

RESULTS

Of 1713 participants, 43% had normoglycemia, 30% Pre-T2D, 9% Undiagnosed T2D, and 18% T2D. Overall, 39% scored 0-2, 49% 3, and 12% 4 LSRI points. T2D prevalence was 55% (POR 0.45; 95% confidence intervals 0.27, 0.76) lower for 4 vs. 0-2 LSRI points with weaker associations for abnormal glycemic status. Despite the low adherence to dietary recommendations (22%), this was the only component related to lower T2D prevalence. The inverse LSRI-T2D association was only observed among Latinos and Japanese Americans in ethnic-specific models. Visceral fat measures were higher in T2D patients and attenuated the LSRI-T2D association.

CONCLUSION

These findings support the role of a healthy lifestyle, especially diet, in T2D prevention with differences across ethnicity.

Modified-Weight Healthy Eating Index-2015 Scores Are More Strongly Associated With Mortality Risk Than Standard Scores

BACKGROUND

Various diet quality scores are consistently and similarly associated with mortality risk. Emerging evidence suggests that individual diet quality components are differentially associated with mortality risk, but it is unclear whether or not modified weights reflective of relative component differences would strengthen mortality associations.

OBJECTIVE

This study examined whether Healthy Eating Index 2015 (HEI-2015) scores with modified (vs standard) component weights are differentially associated with mortality risk.

DESIGN

This was a longitudinal analysis of the National Health and Nutrition Examination Survey III (1988-94) with 23 years of mortality follow-up. The HEI-2015 and modified-weight scores were calculated from one 24-hour recall. The a priori Key Facets HEI was a subset score equivalently weighting fruits, vegetables, whole grains, and seafood and plant proteins. In the least absolute shrinkage and selection operator regression-weighted HEI, components were assigned weights reflecting relative mortality risk associations.

PARTICIPANTS/SETTING

Analyses included 10,789 US adults (aged 20 years and older) who were not pregnant and without prior diabetes, cancer, cardiovascular disease, or chronic kidney disease diagnoses.

MAIN OUTCOME MEASURES

All-cause and cardiovascular disease mortality risk were the primary outcomes examined.

STATISTICAL ANALYSES PERFORMED

Three energy-adjusted HEI scores were assigned to quintiles; covariate-adjusted sex-stratified Cox models with age as the timescale assessed associations between and trends across quintiles of HEI scores and all-cause and cardiovascular disease mortality risk.

RESULTS

Modified-weight HEI scores were associated with 23% to 38% reduced all-cause mortality risk in the highest vs lowest quintile, whereas comparisons were only significant for women (Key Facets P = 0.02 and least absolute shrinkage and selection operator regression-weighted P = 0.001; for men P = 0.06 on both scores), trends across quintiles of modified-weight scores were significant for men and women. The HEI-2015 was not significantly associated with all-cause mortality risk, and none of the scores were associated with cardiovascular disease mortality risk.

CONCLUSIONS

Only modified-weight HEI scores were associated with reduced all-cause mortality risk. Findings suggest modified diet quality weighting schemes warrant further examination to determine their replicability.

Racial and Ethnic Differences in the Population-Attributable Fractions of Alzheimer Disease and Related Dementias

BACKGROUND AND OBJECTIVES

Previous studies estimated that modifiable risk factors explain up to 40% of the dementia cases in the United States and that this population-attributable fraction (PAF) differs by race and ethnicity-estimates of future impact based on the risk factor prevalence in contemporary surveys. The aim of this study was to determine the race-specific and ethnicity-specific PAF of late-onset Alzheimer disease and related dementias (ADRDs) based on the risk factor prevalence and associations observed on the same individuals within a prospective cohort.

METHODS

Data were from Multiethnic Cohort Study participants (African American, Japanese American, Latino, Native Hawaiian, and White) enrolled in Medicare Fee-for-Service. We estimated the PAF based on the prevalence of risk factors at cohort baseline and their mutually adjusted association with subsequent ADRD incidence. Risk factors included low educational attainment and midlife exposures to low neighborhood socioeconomic status, unmarried status, history of hypertension, stroke, diabetes or heart disease, smoking, physical inactivity, short or long sleep duration, obesity, and low-quality diet, as well as APOE ε4 for a subset.

RESULTS

Among 91,881 participants (mean age 59.3 at baseline, 55.0% female participants), 16,507 incident ADRD cases were identified from Medicare claims (1999-2016, mean follow-up 9.3 years). The PAF for nongenetic factors combined was similar in men (24.0% [95% CI 21.3-26.6]) and women (22.8% [20.3-25.2]) but varied across Japanese American (14.2% [11.1-17.2]), White (21.9% [19.0-24.7]), African American (27.8% [22.3-33.0]), Native Hawaiian (29.3% [21.0-36.7]), and Latino (33.3% [27.5-38.5]) groups. The combined PAF was attenuated when accounting for competing risk of death, in both men (10.4%) and women (13.9%) and across racial and ethnic groups (4.7%-25.5%). The combined PAF was also different by age at diagnosis and ADRD subtypes, higher for younger (65-74 years: 43.2%) than older (75-84 years: 32.4%; ≥85 years: 11.3%) diagnoses and higher for vascular or unspecified ADRD than for AD or Lewy body dementia. An additional PAF of 11.8% (9.9-13.6) was associated with APOE ε4, which together with nongenetic risk factors accounted for 30.6% (25.8-35.1) of ADRD.

DISCUSSION

Known risk factors explained about a third of the ADRD cases but with unequal distributions across racial and ethnic groups.

Diet Quality and Body Mass Index Over 20 Years in the Multiethnic Cohort

BACKGROUND

With increasing rates of overweight and obesity and disparities by ethnicity, it is important to understand the role of diet in ameliorating this health problem.

OBJECTIVE

This study examined the relation of diet quality as measured by the Healthy Eating Index 2015 with body mass index (BMI; calculated as kg/m2) and obesity among participants of the Multiethnic Cohort (MEC) in cross-sectional analyses at 3 time points (T-1, T-2, and T-3) over 20 years.

DESIGN

In a subset of 1,860 MEC participants, 3 cross-sectional analyses at cohort entry (1993 to 1996, T-1) and follow-ups in 2003 to 2008 (T-2) and 2013 to 2016 (T-3) were performed.

PARTICIPANTS/SETTING

The cohort consists of African American, Native Hawaiian, Japanese American, Latino, and White adults in Hawaii and California; mean age was 48 years at T-1.

MAIN OUTCOME MEASURE

BMI and weight status in relation to diet quality were measured.

STATISTICAL ANALYSIS

Linear and multinomial logistic regressions were applied to analyze the relation of diet quality with BMI and obesity, while adjusting for known confounders.

RESULTS

Healthy Eating Index 2015 increased by 6.1 and 5.1 units for men and women, respectively, from T-1 to T-3; the respective values for BMI were 1.5 and 2.4. Diet quality was inversely associated with BMI across time: BMI was lower by -0.47, -0.72, and -0.92 units for every 10-point increase in Healthy Eating Index 2015 scores at T-1, T-2, and T-3, respectively (P < .0001 for all). During the 20 years, the association was consistently high among Japanese American participants (-0.79, -0.87, and -1.02) and weakest in African American cohort members (-0.34, -0.37, and -0.40). Higher diet quality was related to lower odds of having obesity at all 3 time points; prevalence odds ratios were 0.72, 0.57, and 0.60.

CONCLUSIONS

These findings suggest that consuming a high-quality diet is related to lower BMI and rates of overweight and obesity but with the strongest association at an older age. To understand the ethnic differences, investigations of dietary habits and behaviors and/or fat distribution patterns will be needed in the future.

Dietary intake and visceral adiposity in older adults: The Multiethnic Cohort Adiposity Phenotype study

Background

There are established links between the accumulation of body fat as visceral adipose tissue (VAT) and the risk of developing obesity-associated metabolic disease. Previous studies have suggested that levels of intake of specific foods and nutrients are associated with VAT accumulation after accounting for total energy intake.

Objective

This study assessed associations between a priori selected dietary factors on VAT quantified using abdominal magnetic resonance imaging.

Methods

The cross-sectional Multiethnic Cohort Adiposity Phenotype Study included n = 395 White, n = 274 Black, n = 269 Native Hawaiian, n = 425 Japanese American and n = 358 Latino participants (mean age = 69 years ± 3 SD). Participants were enrolled stratified on sex, race, ethnicity and body mass index. General linear models were used to estimate the mean VAT area (cm2) for participants categorized into quartiles based on their dietary intake of selected foods/nutrients adjusting for age, sex, racial and ethnic groups, the total percentage fat from whole-body dual energy X-ray absorptiometry and total energy.

Results

There were significant inverse associations with VAT for dietary intake of total vegetables, total fruits (including juice), cereals, whole grains, calcium, copper and dietary fiber (p-trend ≤0.04). Positive trends were observed for VAT for participants who reported higher intake of potatoes, total fat and saturated fatty acids (SFA) (p-trend ≤0.02). Foods/nutrients that met the multiple testing significance threshold were total fruits, whole grains, copper, dietary fiber and SFA intake.

Conclusions

These results highlight foods and nutrients including SFA, total fruit, whole grains, fiber and copper as potential candidates for future research to inform dietary guidelines for the prevention of chronic disease among older adults.

Risk Factors for Type 2 Diabetes in the Multiethnic Cohort

OBJECTIVES

In this report, we investigated the association between established risk factors and type 2 diabetes (T2D) across 5 distinct ethnic groups and explored differences according to T2D definition within the Multiethnic Cohort (MEC) Study.

METHODS

Using the full MEC, with participants in Hawaii and Los Angeles (N=172,230), we applied Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). All participants completed questionnaires asking about demographics, anthropometrics, lifestyle factors, and regular diet. T2D status was determined from self-reported diagnosis/medication and Medicare claims. We assessed the associations between well-established risk factors and T2D in the full cohort, after stratification by ethnic group, according to the T2D definition, and in a biorepository subset. Effect modification by ethnicity was evaluated using Wald's tests.

RESULTS

Overall, 46,500 (27%) participants had an incident T2D diagnosis after a mean follow-up of 17.1±6.9 years. All predictors were significantly associated with T2D: overweight (HR=1.74), obesity (HR=2.90), red meat intake (HR=1.15), short (HR=1.04) and long (HR=1.08) sleep duration, and smoking (HR=1.26) predicted a significantly higher T2D incidence, whereas coffee (HR=0.90) and alcohol (HR=0.78) consumption, physical activity (HR=0.89), and diet quality (HR=0.96) were associated with lower T2D incidence. The strength of these associations was similar across ethnic groups with noteworthy disparities for overweight/obesity, physical activity, alcohol intake, coffee consumption, and diet quality.

CONCLUSIONS

These findings confirm the importance of known risk factors for T2D across ethnic groups, but small differences were detected that may contribute to disparate incidence rates in some ethnic groups, especially for obesity and physical activity.

Reliability and validity of a semi-quantitative food frequency questionnaire: dietary intake assessment among multi-ethnic populations in Northwest China

BACKGROUND

Few multi-ethnic dietary culture-sensitive food frequency questionnaires (FFQ) have been developed due to the complexity and diversity of cooking methods and styles. This study aimed to develop and validate a specific FFQ among multi-ethnic groups in Northwest China.

METHODS

In the reliability study, 139 participants aged 20-65 completed two identical FFQs separated by 3 months. The relative validation of the FFQ was assessed by three 24-h recalls (24HR) employed in the interval of two FFQs, as a reference. Stratified analyses were also conducted by the major ethnic groups (Han nationality or Ethnic minority).

RESULTS

For reproducibility, the median (range) of Spearman's correlation coefficients (SCC) was 0.71 (0.43-0.84) for nutrients. The intra-class correlation coefficients (ICC) covered a spectrum from 0.39 to 0.78 (median: 0.64). Meanwhile, the weighted kappa values ranged from 0.11 to 0.64. For validity, the median (range) of Pearson's correlation coefficients derived from the energy unadjusted and the adjusted values between FFQ and 24HR were 0.61 (0.12-0.79) and 0.56 (0.12-0.77), respectively. The results of correlation coefficients were similar between the two ethnic groups. Moreover, the Bland-Altman plots likewise demonstrated a satisfactory level of agreement between the two methods.

CONCLUSIONS

The FFQ showed acceptable reproducibility and moderate relative validity for evaluating dietary intake among multi-ethnic groups in northwest China. It could be a credible nutritional screening tool for forthcoming epidemiological surveys of these populations.

Atopic allergic conditions and prostate cancer risk and survival in the Multiethnic Cohort study

BACKGROUND

Previous studies investigating relationship between atopic allergic conditions (AACs)-a highly reactive immune state-and prostate cancer (PCa) risk were inconclusive, and few have studied diverse racial/ethnic populations.

METHODS

We analysed 74,714 men aged ≥45 years at enrollment in Multiethnic Cohort study. Using multivariable Cox regression, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for self-reported AAC status on PCa outcomes.

RESULTS

Through 2017, 8697 incident PCa and 1170 related deaths occurred. Twenty-one percent of men reported a history of AACs. AACs were not associated with incident PCa (HR = 0.98, 95% CI: 0.93-1.03) but were significantly inversely associated with PCa mortality (HR = 0.79, 95% CI: 0.67-0.92). This inverse association was consistently observed across all racial/ethnic groups (HR range: 0.60-0.90). Among men diagnosed with PCa, AACs were inversely associated with PCa-specific death (HR = 0.75, 95% CI: 0.63-0.89). Adjusting for potential confounding effect of PSA screening did not meaningfully change the results. No significant heterogeneity was observed in the effect of AACs on PCa incidence or mortality by Dietary Inflammatory Index.

CONCLUSIONS

Hyper-allergic conditions were not associated with PCa incidence but were inversely associated with PCa mortality, suggesting a potential role in reducing tumour progression. Further aetiological research is warranted to understand underlying mechanisms.

Changes in Diet Quality over 10 Years and Subsequent Mortality from Cardiovascular Disease in the Multiethnic Cohort Study

This study investigated how diet quality changes over a ten-year period, assessed using the following four diet quality indexes, the Healthy Eating Index-2015 (HEI-2015), Alternative Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean Diet (aMED), and Dietary Approaches to Stop Hypertension (DASH), were related to mortality from cardiovascular disease (CVD) in the Multiethnic Cohort Study. The analysis included 61,361 participants who completed both the 1993-1996 baseline survey and the 2003-2008 10-year follow-up surveys. Over the mean follow-up period of 13 years after the 10-year survey, 4174 deaths from CVD were identified. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox models. Increases in diet quality scores were associated with a reduced risk of CVD mortality for all indexes: HRs per one SD increment of 0.94 to 0.99 (HR (95% CI), 0.96 (0.92-1.01) for HEI-2015, 0.96 (0.91-1.01) for AHEI-2010, 0.99 (0.94-1.04) for aMED, and 0.94 (0.89-0.99) for DASH) in men and 0.88 to 0.92 (0.88 (0.84-0.92) for HEI-2015, 0.90 (0.85-0.95) for AHEI-2010, 0.89 (0.84-0.95) for aMED, and 0.92 (0.87-0.96) for DASH) in women. The inverse association generally did not vary by race and ethnicity, age, body mass index, smoking, and hypertension in each sex. Our findings suggest that improving diet quality and maintaining a high-quality diet over time may help reduce the risk of CVD mortality and could also be beneficial for those at higher risk of CVD.

Association of Habitual Intake of Probiotic Supplements and Yogurt with Characteristics of the Gut Microbiome in the Multiethnic Cohort Adiposity Phenotype Study

Consumption of probiotics and/or yogurt could be a solution for restoring the balance of the gut microbiota. This study examined associations of regular intake of probiotic supplements or yogurt with the gut microbiota among a diverse population of older adults (N=1,861; 60-72 years). Fecal microbial composition was obtained from 16S rRNA gene sequencing (V1-V3 region). General Linear Models were used to estimate the associations of probiotic supplement or yogurt intake with microbiome measures adjusting for covariates. Compared to non-yogurt consumers (N=1,023), regular yogurt consumers (≥once/week, N=818) had greater Streptococcus (β=0.29, P=0.0003) and lower Odoribacter (β=-0.33, P<0.0001) abundance. The directions of the above associations were consistent across the five ethnic groups but stronger among Japanese Americans (Streptococcus: β=0.56, P=0.0009; Odoribacter: β=-0.62, P=0.0005). Regular intake of probiotic supplements (N=175) was not associated with microbial characteristics (i.e., alpha diversity and the abundance of 152 bacteria genera). Streptococcus is one of the predominant bacteria genera in yogurt products, which may explain the positive association between yogurt consumption and Streptococcus abundance. Our analyses suggest that changes in Odoribacter were independent of changes in Streptococcus abundance. Future studies may investigate whether these microbial genera and their sub-level species mediate potential pathways between yogurt consumption and health.

Healthful Plant-Based Dietary Pattern and Risk of Hepatocellular Carcinoma in a Multiethnic Population: A Cohort Study

BACKGROUND

Plant-based dietary patterns assessed by a priori indices are associated with various health outcomes, but have rarely been examined in relation to liver cancer.

OBJECTIVES

This study investigated the associations between plant-based diets and risk of hepatocellular carcinoma (HCC) and evaluated whether the associations vary by sex and race and ethnicity.

METHODS

Data were from a total of 170,321 African American, Japanese American, Latino, Native Hawaiian, and White adults aged 45-75 y who completed a food frequency questionnaire in the Multiethnic Cohort Study. Cox models with adjustment for potential confounders were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for HCC according to 3 plant-based diet scores: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI).

RESULTS

During a mean follow-up of 19.6 y, 722 incident HCC cases were identified. Multivariate-adjusted HR (95% CI) per 10-point increase was 0.82 (0.71-0.94) for PDI, 0.84 (0.74-0.96) for hPDI, and 1.08 (0.95-1.23) for uPDI. We found no significant differences by sex (all Pheterogeneity ≥ 0.53) or race and ethnicity (all Pheterogeneity ≥ 0.31).

CONCLUSION

Greater adherence to plant-based diets rich in healthy plant foods and low in less healthy plant foods is associated with a reduced risk of HCC in a multiethnic population.

Population-attributable risk of modifiable lifestyle factors to hepatocellular carcinoma: The multi-ethnic cohort

BACKGROUND AND AIMS

Lifestyle factors are well associated with risk of hepatocellular carcinoma (HCC). However, the impact of reducing adverse lifestyle behaviours on population-level burden of HCC is uncertain.

METHODS

We conducted prospective analysis of the population-based multi-ethnic cohort (MEC) with linkage to cancer registries. The association of lifestyle factors (smoking, alcohol, diet quality assessed by alternate Mediterranean diet score, coffee drinking, physical activity and body mass index) with HCC incidence was examined using Cox regression. Population-attributable risk (PAR, %) for the overall, lean and overweight/obese populations was determined.

RESULTS

A total of 753 incident cases of HCC were identified in 181,346 participants over median follow-up of 23.1 years. Lifestyle factors associated with elevated HCC risk included former/current smoking, heavy alcohol use, poor diet quality, lower coffee intake and obesity, but not physical activity. The lifestyle factor with highest PAR was lower coffee intake (21.3%; 95% CI: 8.9%-33.0%), followed by current smoking (15.1%; 11.1%-19.0%), obesity (14.5%; 9.2%-19.8%), heavy alcohol use (7.1%; 3.5%-10.6%) and lower diet quality (4.1%; 0.1%-8.1%). The combined PAR of all high-risk lifestyle factors was 51.9% (95% CI: 30.1%-68.6%). A higher combined PAR was observed among lean (65.2%, 26.8%-85.7%) compared to overweight/obese (37.4%, 11.7%-58.3%) participants. Adjusting for viral hepatitis status in a linked MEC-Medicare dataset resulted in similar PAR results.

CONCLUSIONS

Modifying lifestyle factors, particularly coffee intake, may have a substantial impact on HCC burden in diverse populations, with greater impact among lean adults. Diet and lifestyle counselling should be incorporated into HCC prevention strategies.

Changes in Breast Cancer Risk and Risk Factor Profiles among U.S.-Born and Immigrant Asian American Women Residing in the San Francisco Bay Area

BACKGROUND

Breast cancer incidence rates in women of Asian descent have been increasing in the United States and Asia.

METHODS

In a case-control study of Asian American women from the San Francisco Bay Area, we assessed associations with birthplace and migration-related characteristics and compared risk factors between Asian American and non-Hispanic White women by birthplace and birth cohort.

RESULTS

Birthplace and migration-related characteristics were associated with breast cancer risk only among women in the younger birth cohort (1951-1984) that comprised 355 cases diagnosed at age ≤55 years and 276 sister and population controls. Breast cancer risk was marginally increased among foreign-born women [OR = 1.40; 95% confidence interval (CI), 0.97-2.03] and two-fold among foreign-born Chinese women (OR = 2.16; 95% CI, 1.21-3.88). Two-fold increased risks were associated with migration at age ≥40 years and longer U.S. residence (≥30 years or ≥75% of life). The education level was high among both cases and controls. Differences in the prevalence of risk factors by birthplace and birth cohort suggest temporal changes in reproductive and lifestyle-related factors. The prevalence in risk factors was similar between foreign-born and U.S.-born women in the younger birth cohort, and did not fully explain the observed associations with birthplace and other migration characteristics.

CONCLUSIONS

In contrast to studies from earlier decades, younger foreign-born Asian American women had a higher risk of breast cancer than U.S.-born Asian American women.

IMPACT

It is important and urgent to understand what factors drive the increasing burden of breast cancer in women of Asian descent and implement effective prevention programs.

Diet Quality and All-Cause Mortality in Women with Breast Cancer from the Breast Cancer Family Registry

BACKGROUND

The impact of diet on breast cancer survival remains inconclusive. We assessed associations of all-cause mortality with adherence to the four diet quality indices: Healthy Eating Index-2015 (HEI-2015), Alternative Healthy Eating Index (AHEI), Alternative Mediterranean Diet (aMED), and Dietary Approaches to Stop Hypertension (DASH).

METHODS

Dietary intake data were evaluated for 6,157 North American women enrolled in the Breast Cancer Family Registry who had been diagnosed with invasive breast cancer from 1993 to 2011 and were followed through 2018. Pre-diagnosis (n = 4,557) or post-diagnosis (n = 1,600) dietary intake was estimated through a food frequency questionnaire. During a median follow-up time of 11.3 years, 1,265 deaths occurred. Cox proportional hazards models were used to estimate multivariable-adjusted HR and 95% confidence intervals (CI).

RESULTS

Women in the highest versus lowest quartile of adherence to the HEI-2015, AHEI, aMED, and DASH indices had a lower risk of all-cause mortality. HR (95% CI) were 0.88 (0.74-1.04; Ptrend = 0.12) for HEI-2015; 0.82 (0.69-0.97; Ptrend = 0.02) for AHEI; 0.73 (0.59-0.92; Ptrend = 0.02) for aMED; and 0.78 (0.65-0.94; Ptrend = 0.006) for DASH. In subgroup analyses, the associations with higher adherence to the four indices were similar for pre- or post-diagnosis dietary intake and were confined to women with a body mass index <25 kg/m2 and women with hormone receptor positive tumors.

CONCLUSIONS

Higher adherence to the HEI-2015, AHEI, aMED, and DASH indices was associated with lower mortality among women with breast cancer.

IMPACT

Adherence to a healthy diet may improve survival of women with breast cancer.

Validation and Comparison of Nutrient Intakes from Two Dietary Questionnaires Developed for the Multiethnic Cohort Study

BACKGROUND

Quantitative food frequency questionnaires (QFFQs) are often used to measure dietary intakes in large cohort studies but the impact of updating these questionnaires over time is not often examined.

OBJECTIVE

This study compared nutrient intakes estimated from two different QFFQs to each other and to intakes calculated from three 24-hour dietary recalls (24HDRs).

DESIGN

This study used a cross-sectional design.

PARTICIPANTS/SETTING PARTICIPANTS

Participants (N = 352) were members of the Multiethnic Cohort Study from five racial and ethnic groups (African American, Japanese American, Latino American, Native Hawaiian, and White) who lived in Hawaii and Los Angeles. They were recruited in 2010 and asked to complete two QFFQs, two months apart, and three 24HDRs in the time between completion of the QFFQs. One questionnaire had been developed for a baseline survey (baseline QFFQ) at the start of the Multiethnic Cohort Study during 1993-1996, and the other was updated for a follow-up study 10 years later (10-year QFFQ).

MAIN OUTCOME MEASURES

Daily intakes of energy and nine nutrients were estimated from both QFFQs, and from the average of three 24HDRs.

STATISTICAL ANALYSES PERFORMED

Pearson's correlation coefficients were calculated between log-transformed nutrient intakes from each QFFQ and the 24HDRs and between the two QFFQs overall, by sex, and by race and ethnicity.

RESULTS

Correlations for the 10-year QFFQ with the 24HDRs (average = 0.45) were higher than for the baseline QFFQ (average = 0.41), although the differences were not statistically significant. The increase in correlations was particularly pronounced for Native Hawaiian and African American participants. When absolute values were adjusted for energy intake, the average correlations were higher at 0.57 for the baseline QFFQ and 0.58 for the 10-year QFFQ overall and this pattern was seen in most racial and ethnic subgroups. The average correlations between the two QFFQs were 0.73 for both absolute intakes and nutrient densities overall.

CONCLUSIONS

Correlations of nutrient intakes between the two QFFQs and 24HDRs were similar, and intakes from the two QFFQs were highly correlated. QFFQs updated for changes to the food supply may provide improved assessment for cohort studies that include diverse populations.

Dietary omega-3 fatty acids and endometrial cancer risk in the Epidemiology of Endometrial Cancer Consortium: An individual-participant meta-analysis

BACKGROUND

Limited data from prospective studies suggest that higher dietary intake of long-chain omega-3 polyunsaturated fatty acids (LCn3PUFA), which hold anti-inflammatory properties, may reduce endometrial cancer risk; particularly among certain subgroups characterized by body mass and tumor pathology.

MATERIALS AND METHODS

Data from 12 prospective cohort studies participating in the Epidemiology of Endometrial Cancer Consortium were harmonized as nested case-control studies, including 7268 endometrial cancer cases and 26,133 controls. Habitual diet was assessed by food frequency questionnaire, from which fatty acid intakes were estimated. Two-stage individual-participant data mixed effects meta-analysis estimated adjusted odds ratios (OR) and 95% confidence intervals (CI) through logistic regression for associations between study-specific energy-adjusted quartiles of LCn3PUFA and endometrial cancer risk.

RESULTS

Women with the highest versus lowest estimated dietary intakes of docosahexaenoic acid, the most abundant LCn3PUFA in diet, had a 9% increased endometrial cancer risk (Quartile 4 vs. Quartile 1: OR 1.09, 95% CI: 1.01-1.19; P trend = 0.04). Similar elevated risks were observed for the summary measure of total LCn3PUFA (OR 1.07, 95% CI: 0.99-1.16; P trend = 0.06). Stratified by body mass index, higher intakes of LCn3PUFA were associated with 12-19% increased endometrial cancer risk among overweight/obese women and no increased risk among normal-weight women. Higher associations appeared restricted to White women. The results did not differ by cancer grade.

CONCLUSION

Higher dietary intakes of LCn3PUFA are unlikely to reduce endometrial cancer incidence; rather, they may be associated with small to moderate increases in risk in some subgroups of women, particularly overweight/obese women.

Reproducibility and validity of the Toronto-modified Harvard food frequency questionnaire in a multi-ethnic sample of young adults

BACKGROUND/OBJECTIVES

To assess the reproducibility and validity of a Toronto-modified Harvard food frequency questionnaire (FFQ) among a multi-ethnic sample of young adults.

SUBJECTS/METHODS

A total of 150 participants recruited from the Toronto Nutrigenomics and Health Study cohort who had existing dietary intakes assessed by FFQ (FFQ1) and reassessment one year later (FFQ2). Of these, 100 participants also completed a three-day food record to evaluate the validity of the FFQ for 38 nutrients (energy, 14 macronutrients, 22 micronutrients, and 1 bioactive). Analyses were also stratified between the two major ethnic groups (Caucasian and East Asian).

RESULTS

Among the full sample, mean intakes of most nutrients (27/38) did not differ significantly between estimates derived from FFQ2 compared to the three-day food record. Energy, sex, and ethnicity adjusted deattenuated Pearson correlation coefficients ranged from 0.20 to 0.92 (mean r = 0.52 ± 0.15), and 34/38 validity coefficients were r ≥ 0.32. Gross misclassification of intakes between FFQ2 and the three-day food record was low (<6%), but energy, polyunsaturated fatty acids (PUFA), and sodium were underestimated by FFQ2. Mean intakes between FFQ1 and FFQ2 did not differ significantly for any nutrient. Between the two major ethnic groups, mean validity coefficients were similar, but varied for individual nutrients with saturated fat, PUFA, and omega 3 being among the most discrepant.

CONCLUSIONS

Compared to a three-day food record, the Toronto-modified Harvard FFQ is a reproducible and valid tool to estimate dietary intake among a multi-ethnic sample of young adults. However, incorporation of protocols to improve the assessment of culturally diverse diets should be considered.

Modifying effects of race and ethnicity and APOE on the association of physical activity with risk of Alzheimer's disease and related dementias

INTRODUCTION

We investigated whether the protective association of physical activity with risk of Alzheimer's disease and related dementias (ADRD) has genetic or behavioral variations.

METHODS

In the Multiethnic Cohort, we analyzed moderate or vigorous physical activity (MVPA) reported at ages 45 to 75 among 88,047 participants in relation to 13,039 incident diagnoses of late-onset ADRD identified in Medicare claims (1999 to 2014), by five racial and ethnic groups, hours sitting, and in a subset (16%), apolipoprotein E (APOE) genotype.

RESULTS

MVPA was inversely associated with ADRD (hazard ratio for ≥14 vs <2.5 hours/week: 0.83, 95% confidence interval [CI]: 0.76 to 0.90 in men; 0.88, 5% CI: 0.81 to 0.95 in women). The association was inverse in all racial and ethnic groups except Black participants (P-heterogeneity = 0.52), but stronger in individuals with lower levels of sitting duration or those who do not carry the APOE e4 risk allele.

DISCUSSION

The different effects of physical activity by sitting duration and APOE genotype warrant further research.

Change in the inflammatory potential of diet over 10 years and subsequent mortality: the Multiethnic Cohort Study

Dietary inflammatory potential assessed by the Dietary Inflammatory Index (DII®) has been associated with health outcomes. However, longitudinal changes in the DII in relation to health outcomes rarely have been studied. This study aimed to examine change in the DII score over 10 years and its association with subsequent mortality in the Multiethnic Cohort. The analysis included 56 263 African American, Japanese American, Latino, Native Hawaiian and White participants who completed baseline (45-75 years) and 10-year follow-up surveys, including a FFQ. Mean energy-adjusted DII (E-DII) decreased over 10 years in men (from -0·85 to -1·61) and women (from -1·80 to -2·47), reflecting changes towards a more anti-inflammatory diet. During an average follow-up of 13·0 years, 16 363 deaths were identified. In multivariable Cox models, compared with anti-inflammatory stable individuals, risk of all-cause mortality was increased with pro-inflammatory change in men (hazard ratio (HR) = 1·13, 95 % CI 1·03, 1·23) and women (HR = 1·22, 95 % CI 1·13, 1·32). Per one-point increase in E-DII score over time, HR was 1·02 (95 % CI 1·00, 1·03) for men and 1·06 (95 % CI 1·04, 1·07) for women (P for heterogeneity < 0·001). While no heterogeneity by race and ethnicity was observed for men, the increased risk per one-point increase among women was stronger in non-Whites than in Whites (P for heterogeneity = 0·004). Our findings suggest that a change towards a more pro-inflammatory diet is associated with an increased risk of mortality both in men and women, and that the association is stronger in women, especially non-White women, than in men.

Diet Quality and Pancreatic Cancer Incidence in the Multiethnic Cohort

BACKGROUND

Data on diet quality and pancreatic cancer are limited. We examined the relationship between diet quality, assessed by the Healthy Eating Index-2015 (HEI-2015), the Alternative Healthy Eating Index-2010 (AHEI-2010), the alternate Mediterranean Diet (aMED) score, the Dietary Approaches to Stop Hypertension (DASH) score and the energy-adjusted Dietary Inflammatory Index (E-DII), and pancreatic cancer incidence in the Multiethnic Cohort Study.

METHODS

Diet quality scores were calculated from a validated food frequency questionnaire administered at baseline. Cox models were used to calculate HR and 95% confidence intervals (CI) adjusted for age, sex, race/ethnicity, education, diabetes, family history of pancreatic cancer, physical activity, smoking variables, total energy intake, body mass index (BMI), and alcohol consumption. Stratified analyses by sex, race/ethnicity, smoking status, and BMI were conducted.

RESULTS

Over an average follow-up of 19.3 years, 1,779 incident pancreatic cancer cases were identified among 177,313 participants (average age of 60.2 years at baseline, 1993-1996). Overall, we did not observe associations between the dietary pattern scores and pancreatic cancer (aMED: 0.98; 95% CI, 0.83-1.16; HEI-2015: 1.03; 95% CI, 0.88-1.21; AHEI-2010: 1.03; 95% CI, 0.88-1.20; DASH: 0.92; 95% CI, 0.79-1.08; E-DII: 1.05; 95% CI, 0.89-1.23). An inverse association was observed with DASH for ever smokers (HR, 0.75; 0.61-0.93), but not for nonsmokers (HR, 1.05; 0.83-1.32).

CONCLUSIONS

The DASH diet showed an inverse association with pancreatic cancer among ever smokers, but does not show a protective association overall.

IMPACT

Modifiable measures are needed to reduce pancreatic cancer burden in these high-risk populations; our study adds to the discussion of the benefit of dietary changes.

Diet quality and risk of gastric adenocarcinoma: The Multiethnic Cohort

BACKGROUND

Certain dietary patterns (i.e., low intake of fruit/vegetables and high intake of salt and processed meats) have been associated with the risk of gastric cancer. However, it is unclear whether overall diet quality assessed by predefined indices that consider the complexity of dietary intake is associated with gastric cardia and distal adenocarcinoma.

OBJECTIVES

To examine the association of a variety of diet indices with the risk of gastric cardia and distal adenocarcinoma and assess whether there are any subgroups that may benefit from better diets to reduce the risk of gastric adenocarcinoma.

METHODS

Dietary indices of interest included the Alternative Healthy Index (AHEI)-2010, Healthy Eating Index (HEI)-2015, the Dietary Approach to Stop Hypertension, alternate Mediterranean diet (aMED), and the energy-adjusted Dietary Inflammatory Index.

RESULTS

After an average follow-up time of 19.2 years, there were 836 incident cases of gastric distal adenocarcinoma and 207 cases of gastric cardia adenocarcinoma. We did not observe any significant associations between the dietary indices and gastric cancer for either anatomic site. Among former aspirin users, we observed an inverse association between aMED with distal cancer (HRQ5 vs. Q1: 0.64; 95% CI: 0.33, 1.23; P-trend = 0.03). Never smokers, who showed high-quality diet according to AHEI-2010, exhibited a 40% decreased risk of gastric distal cancer compared with those with the poorest-quality AHEI-2010 diet (HRQ5 vs. Q1: 0.60; 95% CI: 0.41, 0.88; P-trend = 0.08).

CONCLUSIONS

In a multiethnic population, we did not observe overall significant associations between these dietary quality indices and risk of gastric cancer. However, among former aspirin users and never smokers, there could be a reduction of gastric distal adenocarcinoma risk with a higher adherence to a Mediterranean diet.

Plant-based dietary patterns defined by a priori indices and colorectal cancer risk by sex and race/ethnicity: the Multiethnic Cohort Study

BACKGROUND

Plant-based diets assessed by a priori indices are associated with health outcomes. This study investigated the associations between pre-defined indices of plant-based diets and risk of colorectal cancer (CRC) and evaluated whether the association varies by sex, race and ethnicity, and anatomic subsite of tumors.

METHODS

A total of 79,952 men and 93,475 women who participated in the Multiethnic Cohort Study were included. Primary outcome was incidence of invasive CRC. Cox models were used to estimate the risk of CRC across quintiles of three plant-based diet scores: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI).

RESULTS

During a mean follow-up of 19.2 years, 4976 incident CRC were identified. Among men, multivariable-adjusted HR (95% CI) for the highest vs. lowest quintiles was 0.77 (0.67-0.88) for PDI, and 0.80 (0.70-0.91) for hPDI, while no significant association was found for uPDI among men and for all indices among women. In men, the inverse association for PDI was stronger in Japanese American, Native Hawaiian, and White groups than African American or Latino group (P for heterogeneity = 0.01) and for left colon and rectal tumors than right tumors (P for heterogeneity = 0.005), whereas the decreased risk with hPDI was found consistently across racial and ethnic groups and subsites.

CONCLUSIONS

Greater adherence to plant-based diets rich in healthy plant foods and low in less healthy plant foods is associated with a reduced risk of CRC in men, but not in women. The strength of the association among men may vary by race and ethnicity and anatomic subsite of tumors.

Predicting nicotine metabolism across ancestries using genotypes

BACKGROUND

There is a need to match characteristics of tobacco users with cessation treatments and risks of tobacco attributable diseases such as lung cancer. The rate in which the body metabolizes nicotine has proven an important predictor of these outcomes. Nicotine metabolism is primarily catalyzed by the enzyme cytochrone P450 (CYP2A6) and CYP2A6 activity can be measured as the ratio of two nicotine metabolites: trans-3'-hydroxycotinine to cotinine (NMR). Measurements of these metabolites are only possible in current tobacco users and vary by biofluid source, timing of collection, and protocols; unfortunately, this has limited their use in clinical practice. The NMR depends highly on genetic variation near CYP2A6 on chromosome 19 as well as ancestry, environmental, and other genetic factors. Thus, we aimed to develop prediction models of nicotine metabolism using genotypes and basic individual characteristics (age, gender, height, and weight).

RESULTS

We identified four multiethnic studies with nicotine metabolites and DNA samples. We constructed a 263 marker panel from filtering genome-wide association scans of the NMR in each study. We then applied seven machine learning techniques to train models of nicotine metabolism on the largest and most ancestrally diverse dataset (N=2239). The models were then validated using the other three studies (total N=1415). Using cross-validation, we found the correlations between the observed and predicted NMR ranged from 0.69 to 0.97 depending on the model. When predictions were averaged in an ensemble model, the correlation was 0.81. The ensemble model generalizes well in the validation studies across ancestries, despite differences in the measurements of NMR between studies, with correlations of: 0.52 for African ancestry, 0.61 for Asian ancestry, and 0.46 for European ancestry. The most influential predictors of NMR identified in more than two models were rs56113850, rs11878604, and 21 other genetic variants near CYP2A6 as well as age and ancestry.

CONCLUSIONS

We have developed an ensemble of seven models for predicting the NMR across ancestries from genotypes and age, gender and BMI. These models were validated using three datasets and associate with nicotine dosages. The knowledge of how an individual metabolizes nicotine could be used to help select the optimal path to reducing or quitting tobacco use, as well as, evaluating risks of tobacco use.

Risk of Alzheimer's disease and related dementia by sex and race/ethnicity: The Multiethnic Cohort Study

INTRODUCTION

Data are limited for comparison of sex- and race/ethnicity-specific risks of Alzheimer's disease and related dementia (ADRD).

METHODS

In the population-based Multiethnic Cohort, we estimated the age-standardized diagnostic incidence rate (ASDIR) and relative risk of late-onset ADRD (n = 16,410) among 105,796 participants based on Medicare claims (1999-2014) by sex and race/ethnicity.

RESULTS

The ASDIR for ADRD was higher for women (17.0 per 1000 person-years) than for men (15.3) and varied across African Americans (22.9 in women, 21.5 in men), Native Hawaiians (19.3, 19.4), Latinos (16.8, 14.7), Whites (16.4, 15.5), Japanese Americans (14.8, 13.8), and Filipinos (12.5, 9.7). Similar risk patterns were observed for AD. Adjustment for education and cardiometabolic diseases attenuated the differences. Accounting for deaths from competing causes increased the sex difference, while reducing the racial/ethnic differences. Less racial/ethnic disparity was detected among apolipoprotein E (APOE) e4 carriers.

DISCUSSION

More research is needed to understand the sex and racial/ethnic differences in ADRD.

Iron overload phenotypes and HFE genotypes in white hemochromatosis and iron overload screening study participants without HFE p.C282Y/p.C282Y

BACKGROUND

Screening program participants with iron overload (IO) phenotypes without HFE p.C282Y/p.C282Y are incompletely characterized.

METHODS

We studied white participants who had IO phenotypes without p.C282Y/p.C282Y in post-screening clinical examinations (CE). We defined IO phenotypes as a) elevated serum ferritin (SF) and transferrin saturation (TS) at screening and CE, and b) absence of IO treatment, anemia, transfusion >10 units, alcohol intake >30 g/d, hepatitis B or C, and pregnancy. We defined IO-related disease as elevated alanine or aspartate aminotransferase (ALT/AST) or swelling/tenderness of 2nd/3rd metacarpophalangeal (MCP) joints. All participants had HFE p.C282Y and p.H63D genotyping.

RESULTS

There were 32 men and 26 women (mean age 54±16 y). Median food/supplemental iron intakes were 14.3/0.0 mg/d. Relative risks of HFE genotypes were 12.9 (p.C282Y/p.H63D), 3.0 (p.H63D/p.H63D), 1.9 (p.C282Y/wt), 0.9 (p.H63D/wt), and 0.5 (wt/wt) compared to 42,640 white screening participants without IO phenotypes or p.C282Y/p.C282Y. Regression on SF revealed positive associations: MCV (p = 0.0006; β coefficient = 0.4531); swelling/tenderness of MCP joints (p = 0.0033; β = 0.3455); and p.H63D/wt (p = 0.0015; β = 0.4146). IO-related disease (18 elevated ALT/AST, one swelling/tenderness of MCP joints) occurred in 19 participants (7 men, 12 women). Median MCV was higher in participants with IO-related disease (97 fL vs. 94 fL; p = 0.0007). Logistic regression on IO-related disease revealed a significant association with diabetes (p = 0.0416; odds ratio 18.9 (95% confidence interval 1.0, 341.1)).

CONCLUSIONS

In the present 58 screening program participants who had IO phenotypes without HFE p.C282Y/p.C282Y, relative risks of HFE genotypes p.C282Y/p.H63D, p.H63D/p.H63D, and p.C282Y/wt were significantly higher than in 42,640 white screening participants with neither IO phenotypes nor p.C282Y/p.C282Y. SF was significantly associated with MCV, swelling/tenderness of 2nd/3rd MCP joints, and p.H63D/wt. IO-related disease was significantly associated with MCV and diabetes.

Valuing the Diversity of Research Methods to Advance Nutrition Science

The ASN Board of Directors appointed the Nutrition Research Task Force to develop a report on scientific methods used in nutrition science to advance discovery, interpretation, and application of knowledge in the field. The genesis of this report was growing concern about the tone of discourse among nutrition professionals and the implications of acrimony on the productive study and translation of nutrition science. Too often, honest differences of opinion are cast as conflicts instead of areas of needed collaboration. Recognition of the value (and limitations) of contributions from well-executed nutrition science derived from the various approaches used in the discipline, as well as appreciation of how their layering will yield the strongest evidence base, will provide a basis for greater productivity and impact. Greater collaborative efforts within the field of nutrition science will require an understanding that each method or approach has a place and function that should be valued and used together to create the nutrition evidence base. Precision nutrition was identified as an important emerging nutrition topic by the preponderance of task force members, and this theme was adopted for the report because it lent itself to integration of many approaches in nutrition science. Although the primary audience for this report is nutrition researchers and other nutrition professionals, a secondary aim is to develop a document useful for the various audiences that translate nutrition research, including journalists, clinicians, and policymakers. The intent is to promote accurate, transparent, verifiable evidence-based communication about nutrition science. This will facilitate reasoned interpretation and application of emerging findings and, thereby, improve understanding and trust in nutrition science and appropriate characterization, development, and adoption of recommendations.

Body Fat Distribution, Glucose Metabolism, and Diabetes Status Among Older Adults: The Multiethnic Cohort Adiposity Phenotype Study

BACKGROUND

As the proportion of visceral (VAT) to subcutaneous adipose tissue (SAT) may contribute to type 2 diabetes (T2D) development, we examined this relation in a cross-sectional design within the Multiethnic Cohort that includes Japanese Americans known to have high VAT. The aim was to understand how ectopic fat accumulation differs by glycemic status across ethnic groups with disparate rates of obesity, T2D, and propensity to accumulate VAT.

METHODS

In 2013-2016, 1,746 participants aged 69.2 (standard deviation, 2.7) years from five ethnic groups completed questionnaires, blood collections, and whole-body dual X-ray absorptiometry and abdominal magnetic resonance imaging scans. Participants with self-reported T2D and/or medication were classified as T2D, those with fasting glucose >125 and 100-125 mg/dL as undiagnosed cases (UT2D) and prediabetes (PT2D), respectively. Using linear regression, we estimated adjusted means of adiposity measures by T2D status.

RESULTS

Overall, 315 (18%) participants were classified as T2D, 158 (9%) as UT2D, 518 (30%) as PT2D, and 755 (43%) as normoglycemic (NG), with significant ethnic differences (P < 0.0001). In fully adjusted models, VAT, VAT/SAT, and percent liver fat increased significantly from NG, PT2D, UT2D, to T2D (P < 0.001). Across ethnic groups, the VAT/SAT ratio was lowest for NG participants and highest for T2D cases. Positive trends were observed in all groups except African Americans, with highest VAT/SAT in Japanese Americans.

CONCLUSION

These findings indicate that VAT plays an important role in T2D etiology, in particular among Japanese Americans with high levels of ectopic adipose tissue, which drives the development of T2D to a greater degree than in other ethnic groups.

Inflammatory Cytokines, but Not Dietary Patterns, Are Related to Somatic Symptoms of Depression in a Sample of Women

Background

Depression is a heterogenous disorder with both cognitive and somatic symptom dimensions that may differentially relate to systemic inflammation. Diet, which has the potential to modulate both inflammation levels and mood, is yet to be studied within the context of individual depression dimensions. This study examined the associations between inflammatory cytokines and dietary patterns with depressive symptom dimension profiles among a sample of women recruited in a non-clinical setting.

Methods

Inflammatory cytokines (IL-6 and TNF-α), inflammatory diet (Diet Inflammatory Index; DII), and depressive symptoms (Beck Depression Inventory-II; BDI-II) were measured in 136 females (M age = 22.01 ± 4.02, range 18-59 years). Multiple linear regressions were used to investigate the relationships between inflammatory cytokines and diet with self-reported cognitive, somatic, and total depressive symptoms, adjusting for demographic factors.

Results

Findings showed that increased somatic dimension scores were positively associated with IL-6 (ß = 0.273, p = 0.002) and TNF-α (ß = 0.215, p = 0.017), but not inflammatory diet (p = 0.300). Total BDI-II scores were only positively associated with IL-6 (ß = 0.221, p = 0.012), and cognitive dimension scores were not associated with any inflammation measures.

Conclusions

These findings contribute to existing evidence that inflammatory cytokines are associated with the somatic symptoms of depression. Inflammatory diet index was not associated with depression measures.

A Prospective Analysis of Red and Processed Meat Intake in Relation to Colorectal Cancer in the Black Women's Health Study

BACKGROUND

Black Americans have the highest incidence of colorectal cancer (CRC) of any racial/ethnic group in the United States. High intake of red and processed meats has been associated with an increased CRC risk in predominately White populations. However, 3 prior studies in Black populations, who have been reported to have high intakes of red and processed meats, have reported no associations. Data on a possible association between CRC risk and SFAs and MUFAs, the primary types of fat in red and processed meats, are inconclusive.

OBJECTIVES

We prospectively assessed intakes of processed and unprocessed red meat, SFAs, and MUFAs in relation to CRC risk, utilizing data from the Black Women's Health Study (BWHS, 1995-2018).

METHODS

Dietary data were derived from validated FFQs completed in 1995 and 2001. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression.

RESULTS

Among 52,695 BWHS participants aged 21-69 y at baseline and followed for ≤22 y, 564 women developed incident CRC. Unprocessed red meat intake was associated with a 33% increased CRC risk per 100 g/d (HR: 1.33; 95% CI: 1.03-1.71). Examination of CRC anatomic sites revealed that unprocessed red meat was associated with 2-times increased rectal cancer risk (HR: 2.22; 95% CI: 1.15-4.26). There was no evidence of an interaction with age (pinteraction = 0.4), but unprocessed red meat intake was only associated with a significant increased risk of late-onset CRC (≥50 y of age, HR: 1.41; 95% CI: 1.05-1.88). Processed red meat and total SFA and MUFA intakes were not associated with CRC risk.

CONCLUSIONS

Unprocessed red meat intake was associated with an increased CRC risk in the present study, the first positive evidence that red meat plays a role in the etiology of CRC in Black women. The findings suggest prevention opportunities.

Modifiable Factors and Incident Gout Across Ethnicity Within a Large Multiethnic Cohort of Older Adults

OBJECTIVE

Gout disproportionately affects older Pacific Islander and Black populations relative to White populations. However, the ethnic-specific determinants remain understudied within these groups, as well as within other ethnicities. We examined gout incidence and associations with behavioral factors, including diet, alcohol, and smoking, within a large multiethnic population of older adults from the Multiethnic Cohort Study, which linked prospective cohort data to Medicare gout claims between 1999-2016.

METHODS

Using samples of Black (n = 12,370), Native Hawaiian (n = 6459), Japanese (n = 29,830), Latino (n = 17,538), and White (n = 26,067) participants, we conducted multiple Cox regressions, producing hazard ratios (HRs) and 95% CIs.

RESULTS

Relative to White individuals, Native Hawaiians had the highest risk of gout (HR 2.21, 95% CI 2.06-2.38), followed successively by Black and Japanese participants, whereas Latino individuals had a lower risk of gout (HR 0.78, 95% CI 0.73-0.83). Alcohol use was associated with an increased risk, with significantly greater effects observed among Japanese participants drinking ≥ 3 drinks per day (HR 1.46, 95% CI 1.27-1.66), or > 5 beers per week (HR 1.29, 95% CI 1.17-1.43), compared to White individuals (P_interaction < 0.001). Former smokers with ≥ 20 pack-years had an increased risk (HR 1.14, 95% CI 1.06-1.22). Higher dietary quality was associated with a decreased gout risk, with the largest effect observed among White participants (HR_Q5vsQ1 0.84, 95% CI 0.79-0.90), whereas vitamin C was weakly associated with a decreased risk of gout only among Japanese individuals (HR 0.91, 95% CI 0.85-0.98).

CONCLUSION

Overall, notable ethnic differences were observed in both gout risk and associations with modifiable behavioral factors. Our findings offer crucial insights that may improve precision in preventing and managing gout.

Joint Associations of Race, Ethnicity, and Socioeconomic Status With Mortality in the Multiethnic Cohort Study

Importance

Socioeconomic status may help delineate racial and ethnic inequities in mortality.

Objective

To investigate the joint associations of race, ethnicity, and neighborhood and individual socioeconomic status with mortality.

Design, Setting, and Participants

This prospective analysis used data from the Multiethnic Cohort Study. A population-based sample of participants recruited from California (mainly Los Angeles County) and Hawaii from 1993 to 1996 was followed up until 2013. African American, European American, Japanese American, Latino American, and Native Hawaiian men and women were included. Participants with baseline residential addresses that could not be geocoded or who were missing information on education or adjustment variables were excluded. Data analyses were conducted from January 2018 to December 2020.

Exposures

Neighborhood socioeconomic status (nSES) was derived using US Census block group data on education, occupation, unemployment, household income, poverty, rent, and house values. Participants self-reported their highest education attainment. Five racial and ethnic groups, 2 states of residence, 2 nSES, and 2 education categories were combined to create a joint exposure variable. Low and high nSES were defined as quintiles 1 to 3 and 4 to 5, respectively. Low and high education levels were defined as high school or less and greater than high school graduate, respectively.

Main Outcomes and Measures

All-cause, cardiovascular disease (CVD), cancer, and non-CVD and noncancer deaths were ascertained through 2013 via linkage to death certificates and the US National Death Index. Multivariable Cox proportional hazards regression analyses were conducted.

Results

Among 182 912 participants (100 785 [55.1%] women and 82 127 [44.9%] men; mean [SD] age, 60.0 [8.9] years; 31 138 African American, 45 796 European American, 52 993 Japanese American, 39 844 Latino American, and 13 141 Native Hawaiian participants) with a mean (SD) follow-up of 17 (5) years, there were 63 799 total deaths, including 23 191 CVD deaths, 19 008 cancer deaths, and 21 235 non-CVD and noncancer deaths. The lowest all-cause mortality was found among 15 104 Japanese American participants in Hawaii with high nSES and high education (eg, 2870 all-cause deaths [19.0%]), and this population served as the reference group for all regression analyses. Native Hawaiian participants in Hawaii with low nSES and low education had the highest all-cause mortality HR (2.38; 95% CI, 2.21-2.57). African American and European American participants in California with low nSES and low education had the next highest all-cause mortality HRs (2.01; 95% CI, 1.91-2.11 and 1.98; 95% CI, 1.85-2.12, respectively). Latino American participants in California with low nSES had equivalent all-cause mortality HRs regardless of education level (high education: 1.57; 95% CI, 1.48-1.66; low education: 1.57; 95% CI, 1.50-1.65). Patterns for cause-specific mortality were similar to those for all-cause mortality. For example, Native Hawaiian participants in Hawaii with low nSES and low education had highest CVD mortality HR (2.92; 95% CI, 2.60-3.27) and cancer mortality HR (2.01; 95% CI, 1.77-2.29).

Conclusions and Relevance

These results suggest that joint associations of nSES and education may further delineate racial and ethnic inequities in mortality and that future investigations of racial and ethnic inequities in mortality should consider differences by measures of socioeconomic status, especially for underserved populations.

Variations in Dietary Patterns Defined by the Healthy Eating Index 2015 and Associations with Mortality: Findings from the Dietary Patterns Methods Project

BACKGROUND

It is currently unknown if within high-quality dietary intake there exist distinct dietary patterns associated with health benefits that are identifiable with multidimensional dietary pattern analyses. The purpose of this study was to identify specific dietary patterns and groups therein and their associations with all-cause, CVD, and cancer mortality.

METHODS

We conducted sex-specific k-means cluster analyses within Healthy Eating Index 2015 (HEI-2015) quintile 5 in 3 US cohorts [NIH-American Association of Retired Persons Diet and Health Study (AARP), the Multiethnic Cohort (MEC), Women's Health Initiative Observational Study (WHI OS)], clusters ranging from n = 1190 to n = 12,007. Characterizations incorporated HEI-2015 overall and component-specific percentage adherence goals, using untruncated and truncated radar graphs and shape analyses. Using cohort- and sex-specific Cox proportional hazards models, associations of quintile 5 clusters with all-cause, cardiovascular disease (CVD), and cancer mortality were evaluated relative to quintile 1.

RESULTS

In each cohort sex-specific sample, 3 identified clusters included 16%-62% of participants, providing evidence for variation within high-quality dietary intake. Clusters revealed commonalities in total fruits and whole fruits intakes that exceeded goals and high sodium intake. Dairy and whole grain intakes oftentimes fell below goal. Some clusters were in addition characterized by total vegetables, greens & beans, and seafood & plant protein intakes exceeding goals. All high-quality dietary patterns were associated with a multivariable-adjusted significant 15%-26% lower risk of all-cause death than diet intake in quintile 1 (except for cluster 2 in WHI OS), and with a 16%-25% lower risk of CVD mortality in the AARP and MEC cohorts. Cancer mortality results were inconsistent.

CONCLUSIONS

Multiple ways to achieve a high-quality diet were identified and significant associations with lower all-cause and CVD mortality were seen in some cohorts.

Vitamin D deficiency and insufficiency in Hawaii: Levels and sources of serum vitamin D in older adults

OBJECTIVE

To examine the major sources of vitamin D [25-hydroxyvitamin D (25(OH)D)] and evaluate their collective role on rates of vitamin D deficiency/insufficiency among older adults.

METHODS

Cross-sectional analysis of the relationship between serum 25(OH)D levels and sources of vitamin D (self-reported and objectively validated sun exposure, supplementation, food including fortified sources). Study subjects were part of the Hawaii Longitudinal Study of Personality and Health who completed a clinic visit between 55 and 65 years (M = 59.6) and food frequency questionnaire, and provided serum to assay 25(OH)D (n = 223).

RESULTS

Although mean serum 25(OH)D levels were overall sufficient (34.3 ng/ml, [SD = 10.9]), over one-third of participants (38%) had vitamin D deficiency/insufficiency (<30 ng/ml). Asians were the most likely to be insufficient and Filipinos were the least likely (43% vs. 11%, respectively). Overall, supplement use and sun exposure were both associated with higher 25(OH)D levels and lower risk of vitamin D deficiency/insufficiency. Moreover, Vitamin D sources varied by race/ethnic groups. In multivariate models, higher body mass index, being Asian or Native Hawaiian/Pacific Islander, low supplement use, and low sun exposure were associated with higher risk for vitamin D deficiency/insufficiency (<30 ng/ml).

CONCLUSIONS

Over 1/3 of the older adult sample was vitamin D deficient/insufficient, despite most of the participants living in a tropical climate with year-round access to sun as a vitamin D source. Sun exposure and supplement use, but not food intake, explained differences in vitamin D deficiency/insufficiency in this population.

Diet quality and all-cause and cancer-specific mortality in cancer survivors and non-cancer individuals: the Multiethnic Cohort Study

PURPOSE

We examined post-diagnostic diet quality in relation to all-cause and cancer-specific mortality among adults diagnosed with invasive cancer between cohort entry (45-75 years) and their 10-year follow-up, in comparison with those without invasive cancer during that period, in the Multiethnic Cohort.

METHODS

Data were from 70,045 African Americans, Native Hawaiians, Japanese Americans, Latinos, and Whites (6370 with cancer, 63,675 without cancer). Diet quality was measured by the Healthy Eating Index (HEI)-2015, the Alternative HEI-2010 (AHEI-2010), the alternate Mediterranean Diet (aMED), and the Dietary Approaches to Stop Hypertension (DASH) scores, using a food frequency questionnaire. Multivariable Cox models estimated the association of the dietary indexes at 10-year follow-up and changes since baseline with subsequent mortality.

RESULTS

Post-diagnostic scores from all four indexes were associated with lower mortality: for the highest vs. lowest quartiles, hazard ratio (HR) for all-cause mortality was 0.74 (95% CI 0.67-0.82) for HEI-2015, 0.82 (0.74-0.92) for AHEI-2010, 0.74 (0.66-0.84) for aMED, and 0.82 (0.74-0.91) for DASH. The corresponding HRs for cancer mortality were 0.84 (0.71-1.00), 0.85 (0.71-1.00), 0.71 (0.59-0.85), and 0.84 (0.71-1.00). Compared to stable scores over 10 years (< 0.5 SD change), HR for all-cause mortality was 0.87 (0.79-0.97) for ≥ 1 SD increase in HEI-2015 and was 1.22 to 1.29 for ≥ 1 SD decrease in scores across the four indexes. These HRs were similar to those for participants without cancer.

CONCLUSION

Post-diagnostic high-quality diet was related to lower all-cause and cancer mortality among adult cancer survivors, with risk reduction comparable to that among participants without cancer.