Meat consumption, heterocyclic amines and colorectal cancer risk: the Multiethnic Cohort Study

Greater consumption of red and processed meat has been associated with an increased risk of colorectal cancer in several recent meta-analyses. Heterocyclic amines (HCAs) have been hypothesized to underlie this association. In this prospective analysis conducted within the Multiethnic Cohort Study, we examined whether greater consumption of total, red or processed meat was associated with the risk of colorectal cancer among 165,717 participants who completed a detailed food frequency questionnaire at baseline. In addition, we examined whether greater estimated intake of HCAs was associated with the risk of colorectal cancer among 131,763 participants who completed a follow-up questionnaire that included a meat-cooking module. A total of 3,404 and 1,757 invasive colorectal cancers were identified from baseline to the end of follow-up and from the date of administration of the meat-cooking module to the end of follow-up, respectively. Proportional hazard models were used to estimate basic and multivariable-adjusted relative risks (RRs) and 95% confidence intervals for colorectal cancer associated with dietary exposures. In multivariable models, no association with the risk of colorectal cancer was detected for density-adjusted total meat (RR(Q5 vs. Q1) = 0.93 [0.83-1.05]), red meat (RR = 1.02 [0.91-1.16]) or processed meat intake (RR = 1.06 [0.94-1.19]) or for total (RR = 0.90 [0.76-1.05]) or specific HCA intake whether comparing quintiles of dietary exposure or using continuous variables. Although our results do not support a role for meat or for HCAs from meat in the etiology of colorectal cancer, we cannot rule out the possibility of a modest effect.     

Plasma matrix metalloproteinases and postmenopausal breast cancer risk: a nested case–control study in the Multiethnic Cohort study

The survival of malignant breast cells depends upon the remodeling of the extracellular matrix, including complex interactions with matrix metalloproteinases (MMPs). It has been hypothesized that circulating MMPs may serve as early indicators of breast cancer development in hospital-based case–control studies. A nested case–control study of the association of pre-diagnostic plasma levels of MMPs with the subsequent risk of postmenopausal breast cancer was conducted within the Multiethnic Cohort. During the follow-up period, 713 women with incident invasive breast cancer were identified and individually (1:1) matched to controls. Four types of MMPs (1, 2, 3, and 7) were analyzed by microsphere immunofluorescence assay. Mean plasma levels of MMPs did not differ significantly between cases and controls; nor were there differences in breast cancer risk by MMP level. No difference in the risk of breast cancer by plasma level of the MMPs was found within strata of age, or ethnicity, although MMP-1 levels were positively associated with breast cancer risk in obese women and women by hormone replacement medications (P values for interaction <0.05). Few significant differences in risk by levels of the MMPs were found by any of the clinical variables. Circulating MMPs were not associated with postmenopausal breast cancer risk.     

Risk factors for malignant melanoma in white and non-white/non-African American populations: the multiethnic cohort

It is unknown whether the established risk factors for malignant melanoma in whites influence malignant melanoma risk in non-whites. We examined the risk factors for melanoma among 39,325 whites and 101,229 non-whites/multiracials [Japanese American (47.5%), Latino American (34.8%), Native Hawaiian (2.1%), and multiracial (15.6%), excluding African Americans] in the Multiethnic Cohort study. With an average follow-up of 12.7 years, 581 invasive malignant melanoma (IMM) and 412 melanoma in situ (MIS) cases were identified, of which 107 IMM and 74 MIS were among non-whites/multiracials. The relative risks (RR) and 95% confidence intervals (CI) were estimated by Cox proportional hazards models using days from cohort entry as the underlying time variable. Among non-white/multiracial males, location of IMM tumors differed from those of white males (P < 0.001); and non-white/multiracial females were more likely to be diagnosed with later stage of disease (P < 0.001). After adjusting for potential confounders, age at cohort entry, male sex, higher education, and sunburn susceptibility phenotypes were associated with an increased risk of IMM in non-whites/multiracials (P < 0.05). The risk estimates for age at cohort entry and lighter hair and eye color were greater in non-whites/multiracials than in whites (P(heterogeneity) = 0.062, 0.016, and 0.005, respectively). For MIS risk, RRs between whites and non-whites/multiracials also differed for study location and education (P(heterogeneity) ≤ 0.015). In conclusion, similar to whites, age at cohort entry, male sex, and susceptibility to sunburn phenotypes may be predictive of malignant melanoma risk in non-white populations excluding African Americans.     

Predictors of the timing of natural menopause in the Multiethnic Cohort Study

The timing of natural menopause has implications for several health endpoints; in particular, it is a risk factor for breast cancer. The authors investigated factors influencing the timing of natural menopause among 95,704 women with a mean age of 59.7 years (10th-90th percentile range, 47.0-71.0) in five racial/ethnic groups in the Multiethnic Cohort Study, including non-Latina Whites, Japanese Americans, African Americans, Native Hawai'ians, and Latinas. The authors investigated whether race/ethnicity and several lifestyle and reproductive characteristics were associated with the timing of natural menopause. Race/ethnicity was a significant independent predictor of the timing of natural menopause. Other factors, including smoking, age at menarche, parity, and body mass index, did not significantly alter the race/ethnicity-specific hazard ratios. Relative to non-Latina Whites, natural menopause occurred earlier among Latinas (US-born Latinas: hazard ratio (HR) = 1.10, 95% confidence interval (CI): 1.07, 1.14; non-US-born Latinas: HR = 1.25, 95% CI: 1.21, 1.30) and later among Japanese Americans (HR = 0.93, 95% CI: 0.90, 0.95). These results support the hypothesis that the timing of natural menopause is driven by a combination of genetic, reproductive, and lifestyle factors.     

Effectiveness of a Lifestyle Intervention Program Among Persons at High Risk for Cardiovascular Disease and Diabetes in a Rural Community

Purpose: To evaluate the feasibility of translating the Diabetes Prevention Program (DPP) lifestyle intervention into practice in a rural community. Methods: In 2008, the Montana Diabetes Control Program worked collaboratively with Holy Rosary Healthcare to implement an adapted group-based DPP lifestyle intervention. Adults at high risk for diabetes and cardiovascular disease were recruited and enrolled (N = 101). Participants set targets to reduce fat intake and increase physical activity (≥150 mins/week) in order to achieve a 7% weight loss goal. Findings: Eighty-three percent (n = 84) of participants completed the 16-session core program and 65 (64%) participated in 1 or more after-core sessions. Of those completing the core program, the mean participation was 14.4 ± 1.6 and 3.9 ± 1.6 sessions during the core and after core, respectively. Sixty-five percent of participants met the 150-min-per-week physical activity goal during the core program. Sixty-two percent achieved the 7% weight loss goal and 78% achieved at least a 5% weight loss during the core program. The average weight loss per participant was 7.5 kg (range, 0 to 19.7 kg), which was 7.5% of initial body weight. At the last recorded weight in the after core, 52% of participants had met the 7% weight loss goal and 66% had achieved at least a 5% weight loss. Conclusion: Our findings suggest that it is feasible to implement a group-based DPP in a rural community and achieve weight loss and physical goals that are comparable to those achieved in the DPP.     

Insufficient and excessive amounts of sleep increase the risk of premature death from cardiovascular and other diseases: The Multiethnic Cohort Study

Objective

To explore an independent association between self-reported sleep duration and cause-specific mortality.

Methods

Data were obtained from the Multiethnic Cohort Study conducted in Los Angeles and Hawaii.

Results

Among 61,936 men and 73,749 women with no history of cancer, heart attack or stroke, 19,335 deaths occurred during an average 12.9 year follow-up. Shorter (≤ 5 h/day) and longer (≥ 9 h/day) sleepers of both sexes (vs. 7 h/day) had an increased risk of all-cause and cardiovascular disease (CVD) mortality, but not of cancer mortality. Multivariable hazard ratios for CVD mortality were 1.13 (95% CI 1.00–1.28) for ≤ 5 h/day and 1.22 (95% CI 1.09–1.35) for ≥ 9 h/day among men; and 1.20 (95% CI 1.05–1.36) for ≤ 5 h/day and 1.29 (95% CI 1.13–1.47) for ≥ 9 h/day among women. This risk pattern was not heterogeneous across specific causes of CVD death among men (P_hetero 0.53) or among women (P_hetero 0.72). The U-shape association for all-cause and CVD mortality was observed in all five ethnic groups included in the study and by subgroups of age, smoking status, and body mass index.

Conclusion

Insufficient or excessive amounts of sleep were associated with increased risk of mortality from CVD and other diseases in a multiethnic population.     

The Effects of Soy Consumption before Diagnosis on Breast Cancer Survival: The Multiethnic Cohort Study

This study tested the hypothesis that prediagnostic soy intake was inversely associated with all-cause and breast cancer-specific mortality. The analyses included 3842 women in the Multiethnic Cohort (MEC) study of African Americans, Native Hawaiians, Japanese Americans, Latinos, and Caucasians, who completed a quantitative food frequency questionnaire, aged ≥50 yr at cohort entry, and diagnosed with primary invasive breast cancer following cohort entry (1993–2007). Hazard ratios (HR) and 95% confidence intervals (CI) were estimated from Cox proportional hazards regression with adjustment for known clinical and lifestyle factors. During a mean follow-up after diagnosis of invasive breast cancer of 6.2 ± 3.8 yr, there were 804 deaths including 376 breast cancer-specific deaths. The HR (95%CI) for all-cause and breast cancer-specific morality comparing the highest versus lowest tertiles were 1.03 (0.81–1.33) and 1.03 (0.71–1.50) for soy products and 0.99 (0.82–1.20) and 0.95 (0.71–1.28) for total isoflavones, respectively (P_trend > 0.60 for all). There was limited evidence of differences by hormone receptor status, tumor stage, or ethnic group. Prediagnostic soy intake was unrelated to mortality in postmenopausal women. Our findings are consistent with the literature that soy consumption does not adversely affect breast cancer survival in women.     

Diet impacts mortality from cancer: results from the multiethnic cohort study

Purpose

Cancer is the second leading cause of death in the United States and mortality varies by ethnicity. The objective of this study was to examine the association between cancer mortality and dietary intake among a large multiethnic population.

Methods

A prospective cohort design was used to examine cancer mortality among 146,389 participants. Multiethnic cohort study participants represent five ethnic groups: African American, Native Hawaiian, Japanese American, Latino, and Caucasian. Hazard ratios for cancer mortality by intake levels of five food groups and discretionary fat were calculated using Cox proportional hazards models stratified by sex and ethnicity.

Results

There were a total of 2,028 male and 1,464 female fatal cancer cases at the end of follow-up. Among Japanese American men only, there was a significant protective effect seen in those reporting a high grain intake (HR = 0.49, 95 % CI 0.35–0.69); there was no effect of grain consumption in any other ethnic-sex group. There was no evidence that ethnicity modified associations between fruit, vegetable, meat, dairy, or discretionary fat intake and cancer mortality among men. Associations between food group consumption and risk for cancer mortality among women were similar across ethnic groups.

Conclusions

The considerable reduction in cancer risk associated with high grain consumption among a specific ethnic-sex group, Japanese American men, warrants further investigation. Additional research is needed to validate this observation and determine whether this was a chance finding, or possibly due to differential intake of specific grain subtypes, and/or related to a sex-specific cancer type.     

Obesity and non-Hodgkin lymphoma survival in an ethnically diverse population: the Multiethnic Cohort study

Purpose

Obesity increases mortality for several malignancies, but for non-Hodgkin lymphoma (NHL), the association between body mass index (BMI) and survival is unclear. We examined the association of pre-diagnostic BMI with overall and NHL-specific survival in the multiethnic cohort (MEC) study of African Americans, Native Hawaiians, Japanese Americans, Latinos, and Caucasians.

Methods

MEC participants free of NHL at cohort entry and diagnosed with NHL during follow-up were included in the analyses (n = 1,331). BMI was based on self-reported weight and height at cohort entry and after 6.1 years of cohort entry. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95 % confidence intervals (CI) with BMI as time-varying exposure in relation to all-cause and NHL-specific mortality while adjusting for known confounders.

Results

The mean age at NHL diagnosis was 70.5 (range 45–89) years. After a mean follow-up of 4.3 ± 3.5 years, 667 deaths including 450 NHL-specific deaths occurred. In multivariable models, obese patients (BMI ≥30.0 kg/m²) had higher all-cause (HR 1.46, 95 % CI 1.13–1.87) and NHL-specific (HR 1.77, 95 % CI 1.30–2.41) mortality compared with patients with high-normal BMI (22.5–24.9 kg/m²). For overweight patients (BMI = 25.0–29.9 kg/m²), the respective HRs were 1.21 (95 % CI 0.99–1.49) and 1.36 (95 % CI 1.06–1.75). Cases with low-normal BMI (<22.5 kg/m²) experienced a significant 45 % higher all-cause and a 40 % higher NHL-specific mortality. After stratification by NHL type, the adverse effect of BMI was stronger for chronic lymphocytic leukemia/small lymphocytic lymphoma than for diffuse large B cell lymphoma and follicular lymphoma.

Conclusions

Pre-diagnostic BMI may be a suitable prognostic marker for NHL patients.     

Association of <Emphasis Type="Italic">Helicobacter pylori </Emphasis>infection and diet on the risk of gastric cancer: a case–control study in Hawaii

Objective  The risk factors most strongly associated with gastric cancer are the gastric bacteria Helicobacter pylori and diet. Utilizing data from a case–control study among residents in Hawaii, we examined the association of diet, presence of H. pylori, and non-cardia gastric cancer risk. Methods  Serum taken at diagnosis for cases (n = 212) and at interview for controls (n = 336) was assayed for IgG antibodies to H. pylori group antigens and to a recombinant fragment of the cytotoxin-associated antigen A (CagA) protein, and subjects completed food frequency questionnaires. Risk measures were calculated using logistic regression. The likelihood ratio test was used to assess interactions. Results  Inverse associations were found between gastric cancer risk and increasing intake of several micronutrients and vegetables among all individuals. For H. pylori/CagA-positive subjects, significant trends were present for total, green, and yellow vegetables, while a significant trend was present only for yellow vegetables among H. pylori/CagA-negative individuals. For intestinal gastric cancer, there was a suggestion that intake of vegetables, especially cruciferous vegetables, had a stronger protective effect for the H. pylori/CagA-positive group. Conclusions  Diet may play a greater role in the etiology of non-cardia gastric cancer among individuals with evidence of H. pylori infection than among those without. G. N. Stemmermann is now deceased.