R. Patti Herring

Vegetarian Dietary Patterns and the Risk of Colorectal Cancers

IMPORTANCE Colorectal cancers are a leading cause of cancer mortality, and their primary prevention by diet is highly desirable. The relationship of vegetarian dietary patterns to colorectal cancer risk is not well established. OBJECTIVE To evaluate the association between vegetarian dietary patterns and incident colorectal cancers. DESIGN, SETTING, AND PARTICIPANTS The Adventist Health Study 2 (AHS-2) is a large, prospective, North American cohort trial including 96,354 Seventh-Day Adventist men and women recruited between January 1, 2002, and December 31, 2007. Follow-up varied by state and was indicated by the cancer registry linkage dates. Of these participants, an analytic sample of 77,659 remained after exclusions. Analysis was conducted using Cox proportional hazards regression, controlling for important demographic and lifestyle confounders. The analysis was conducted between June 1, 2014, and October 20, 2014. EXPOSURES Diet was assessed at baseline by a validated quantitative food frequency questionnaire and categorized into 4 vegetarian dietary patterns (vegan, lacto-ovo vegetarian, pescovegetarian, and semivegetarian) and a nonvegetarian dietary pattern. MAIN OUTCOMES AND MEASURES The relationship between dietary patterns and incident cancers of the colon and rectum; colorectal cancer cases were identified primarily by state cancer registry linkages. RESULTS During a mean follow-up of 7.3 years, 380 cases of colon cancer and 110 cases of rectal cancer were documented. The adjusted hazard ratios (HRs) in all vegetarians combined vs nonvegetarians were 0.78 (95% CI, 0.64-0.95) for all colorectal cancers, 0.81 (95% CI, 0.65-1.00) for colon cancer, and 0.71 (95% CI, 0.47-1.06) for rectal cancer. The adjusted HR for colorectal cancer in vegans was 0.84 (95% CI, 0.59-1.19); in lacto-ovo vegetarians, 0.82 (95% CI, 0.65-1.02); in pescovegetarians, 0.57 (95% CI, 0.40-0.82); and in semivegetarians, 0.92 (95% CI, 0.62-1.37) compared with nonvegetarians. Effect estimates were similar for men and women and for black and nonblack individuals. CONCLUSIONS AND RELEVANCE Vegetarian diets are associated with an overall lower incidence of colorectal cancers. Pescovegetarians in particular have a much lower risk compared with nonvegetarians. If such associations are causal, they may be important for primary prevention of colorectal cancers.

Validation of nutrient intake using an FFQ and repeated 24 h recalls in black and white subjects of the Adventist Health Study-2 (AHS-2)

OBJECTIVE To validate a 204-item quantitative FFQ for measurement of nutrient intake in the Adventist Health Study-2 (AHS-2). DESIGN Calibration study participants were randomly selected from the AHS-2 cohort by church, and then subject-within-church. Each participant provided two sets of three weighted 24 h dietary recalls and a 204-item FFQ. Race-specific correlation coefficients (r), corrected for attenuation from within-person variation in the recalls, were calculated for selected energy-adjusted macro- and micronutrients. SETTING Adult members of the AHS-2 cohort geographically spread throughout the USA and Canada. SUBJECTS Calibration study participants included 461 blacks of American and Caribbean origin and 550 whites. RESULTS Calibration study subjects represented the total cohort very well with respect to demographic variables. Approximately 33 % were males. Whites were older, had higher education and lower BMI compared with blacks. Across fifty-one variables, average deattenuated energy-adjusted validity correlations were 0.60 in whites and 0.52 in blacks. Individual components of protein had validity ranging from 0.40 to 0.68 in blacks and from 0.63 to 0.85 in whites; for total fat and fatty acids, validity ranged from 0.43 to 0.75 in blacks and from 0.46 to 0.77 in whites. Of the eighteen micronutrients assessed, sixteen in blacks and sixteen in whites had deattenuated energy-adjusted correlations >or=0.4, averaging 0.60 and 0.53 in whites and blacks, respectively. CONCLUSIONS With few exceptions validity coefficients were moderate to high for macronutrients, fatty acids, vitamins, minerals and fibre. We expect to successfully use these data for measurement error correction in analyses of diet and disease risk.

Recruiting Black/African American men for research on prostate cancer prevention†‡

Black/African American men die of prostate cancer at a greater rate relative to other males. During the period from 1992 to 1998, prostate cancer incidence rates in the United States were 234.2 per 100,000 persons among non‐Hispanic black males and 144.6 per 100,000 persons among white males. The reasons for these increased rates of prostate cancer among black males are largely unknown, but increased mortality is associated with late detection. The authors conducted a longitudinal study of black men that investigated prostate cancer prevention behaviors within this population. The purpose of the current article is to identify successful recruitment strategies that were reported by participants in this study of prevention behaviors.

Race-specific validation of food intake obtained from a comprehensive FFQ: the Adventist Health Study-2.

OBJECTIVE To assess race-specific validity of food and food group intakes measured using an FFQ. DESIGN Calibration study participants were randomly selected from the Adventist Health Study-2 (AHS-2) cohort by church, and then by subject-within-church. Intakes of forty-seven foods and food groups were assessed using an FFQ and then compared with intake estimates measured using six 24 h dietary recalls (24HDR). We used two approaches to assess the validity of the questionnaire: (i) cross-classification by quartile and (ii) de-attenuated correlation coefficients. SETTING Seventh-day Adventist church members geographically spread throughout the USA and Canada. SUBJECTS Members of the AHS-2 calibration study (550 whites and 461 blacks). RESULTS The proportion of participants with exact quartile agreement in the FFQ and 24HDR averaged 46 % (range: 29-87 %) in whites and 44 % (range: 25-88 %) in blacks. The proportion of quartile gross misclassification ranged from 1 % to 11 % in whites and from 1 % to 15 % in blacks. De-attenuated validity correlations averaged 0·59 in whites and 0·48 in blacks. Of the forty-seven foods and food groups, forty-three in whites and thirty-three in blacks had validity correlations >0·4. CONCLUSIONS The AHS-2 questionnaire has good validity for most foods in both races; however, validity correlations tend to be higher in whites than in blacks.

Using the theory of planned behavior to explore attitudes and beliefs about dietary supplements among HIV-positive Black women

BACKGROUND This cross-sectional study investigated whether the theory of planned behavior (TPB) constructs: attitudes, subjective norms, and perceived behavioral control were related to intention of dietary supplements use among African-American women living with Human Immunodeficiency Virus and/or Acquired Immune Deficiency Syndrome (HIV/AIDS). METHODS A closed-ended questionnaire based on the TPB was utilized to explore the use of dietary supplements among a cohort of 153 HIV-positive African-American women. RESULTS Overall, 45% of the respondents used dietary supplements to manage/control their HIV. Combined, attitudes, subjective norms and perceived behavioral control were significant predictors of intention toward dietary supplement use (69% of the variance explained, p<0.0001). Attitudes (β=0.23, p<0.001) and perceived behavioral control (β=0.45, p<0.0001) were found to be significant independent predictors of intention. Behavioral intention and proximal TPB constructs (attitudes, subjective norms, and perceived behavioral control), as well as their underlying beliefs about dietary supplements use, were all found to be significantly more positive in users of dietary supplements compared to non-users (p<0.001). CONCLUSIONS Results showed that attitudes, subjective norms and perceived behavioral control are important predictors in the intention to use dietary supplements for control of HIV among African-American women. Implications from this study suggest that the TPB can be used to better identify and understand salient beliefs that surround intentions to use alternative therapies for management of disease. These beliefs can be used to develop interventions surrounding HIV treatment and care.

Contextual factors influencing health-related quality of life in African American and Latina breast cancer survivors

PurposeThis study explored the relationships between systemic- and individual-level contextual factors and health-related quality of life (HRQOL) in a cohort of African American and Latina breast cancer survivors (BCS).MethodsBaseline questionnaire data of 320 BCS who participated in a HRQOL psycho-educational intervention were abstracted from the parent study. Hierarchical regression analysis tested the independent effects of contextual factors on HRQOL.ResultsHRQOL was higher in BCS who: were diagnosed at < stage 2 (b = − 1.38, p < 0.05), expressed satisfaction with their health care (b = 0.20, p < 0.001), had fewer comorbidities (b = − 0.60, p < 0.001) and depressive symptoms (b = − 0.30, p < 0.001), and practiced healthy diet and exercise habits (b = 0.02, p < 0.05). Demographic and cancer-related factors accounted for 14 % of the variance in HRQOL (F[6, 274] = 7.25, p < 0.001). The socio-cultural context (i.e., ethnicity, life stress, perceived social support) explained 20 % of the variance in HRQOL (FΔ[3, 271] = 27.32, p < 0.001). The health care system context contributed an additional 8 % to explaining HRQOL (FΔ[1, 270] = 34.88, p < 0.001). Health status and behavioral factors accounted for 18 % of the variance (FΔ[4, 266] = 29.55, p < 0.001). The full model explained 59 % of the variance in HRQOL (F[14, 266] = 27.76, p < 0.001).ConclusionsHRQOL in ethnic minority BCS is multifaceted and is significantly influenced by cancer-related, socio-cultural, health care system, health status, and behavioral contextual factors. Therefore, survivorship research and practice must address broad multi-level domains to achieve equitable and optimal breast cancer outcomes.Implications for cancer survivorsTo enhance HRQOL, survivors must be provided the know-how and support to maintain healthy lifestyle and self-management practices. Advocates must engage the care team to consider systemic factors, including life stress and community resources, to be more patient-centered.

Black art posters, an incentive to increase study enrollment among Blacks in a large cohort study

OBJECTIVE Black art posters were offered to replace or augment the established

Cohort Profile: The Adventist Health Study-2 (AHS-2)

10 incentive for questionnaire completion in a longitudinal cohort study. METHOD Eighty-one churches located in the US southern region were divided between two intervention groups, with a control group of 24 churches from the same region. Primary outcome measures were study enrollment rates and questionnaire return rates between December 2003 and July 2004 as a proportion of church goal. RESULTS 9.3% of participants returning questionnaires selected a poster in preference to

Social ecological predictors of prostate-specific antigen blood test and digital rectal examination in black American men.

10. Half of participants offered both monetary and art incentives indicated a poster selection. Crude questionnaire return rates were 57.4% for the pooled intervention churches and 38.2% for the control churches. Enrollment rates among those offered both incentives were significantly higher (p<0.01) than when monetary incentives alone were offered after adjustment for church size, promotional dates, and average income of church members. Survey return rates were also higher in the churches offered both incentives (p=0.04). CONCLUSION These data suggest that the black art posters improved study enrollment and survey return rates. The relatively low rate of poster selection suggests that the art primarily influenced participation indirectly, by creating a more culturally inclusive image of the study.