David Shavlik

The Association between Fatal Coronary Heart Disease and Ambient Particulate Air Pollution: Are Females at Greater Risk?

The purpose of this study was to assess the effect of long-term ambient particulate matter (PM) on risk of fatal coronary heart disease (CHD). A cohort of 3,239 nonsmoking, non-Hispanic white adults was followed for 22 years. Monthly concentrations of ambient air pollutants were obtained from monitoring stations [PM < 10 μm in aerodynamic diameter (PM10), ozone, sulfur dioxide, nitrogen dioxide] or airport visibility data [PM < 2.5 μm in aerodynamic diameter (PM2.5)] and interpolated to ZIP code centroids of work and residence locations. All participants had completed a detailed lifestyle questionnaire at baseline (1976), and follow-up information on environmental tobacco smoke and other personal sources of air pollution were available from four subsequent questionnaires from 1977 through 2000. Persons with prevalent CHD, stroke, or diabetes at baseline (1976) were excluded, and analyses were controlled for a number of potential confounders, including lifestyle. In females, the relative risk (RR) for fatal CHD with each 10-μg/m3 increase in PM2.5 was 1.42 [95% confidence interval (CI), 1.06–1.90] in the single-pollutant model and 2.00 (95% CI, 1.51–2.64) in the two-pollutant model with O3. Corresponding RRs for a 10-μg/m3 increase in PM10-2.5 and PM10 were 1.62 and 1.45, respectively, in all females and 1.85 and 1.52 in postmenopausal females. No associations were found in males. A positive association with fatal CHD was found with all three PM fractions in females but not in males. The risk estimates were strengthened when adjusting for gaseous pollutants, especially O3, and were highest for PM2.5. These findings could have great implications for policy regulations.

Risk factors, lifetime risk, and age at onset of breast cancer

PURPOSE We evaluated the relationship between exposure variables and both lifetime risk and mean age at diagnosis of breast cancer in subjects from the Adventist Health Study who developed breast cancer before the age of 91 years. METHODS Multiple decrement life-table analysis was used. This study provided data from 20,341 women followed for 6 years. RESULTS In the total population, 30-year-old women with a parental history of any cancer or a maternal history of breast cancer had, respectively, 72% (P < 0.002) and 98% (P < 0.03) higher lifetime risks of breast cancer. Thirty-year-old women who had their first delivery after age 24 years or body mass indices above the 50th percentile had, respectively, 53% (P < 0.007) or 57% (P = 0.01) greater lifetime risk of breast cancer. Women who exercised infrequently had a 27% higher life-time risk (P = 0.09) and an age at diagnosis of breast cancer 6.6 years younger (P < 0.005) than other women. CONCLUSIONS Standard risk factors account for substantial increases in lifetime risk of breast cancer and may be associated with differences in age at diagnosis.

Comparison of Adipose Tissue Fatty Acids with Dietary Fatty Acids as Measured by 24-hour Recall and Food Frequency Questionnaire in Black and White Adventists: The Adventist Health Study

PURPOSE To calibrate and compare intake of different fats and individual fatty acids as assessed with a food frequency questionnaire (FFQ) against that estimated with (i) a series of dietary recalls and; (ii) the relative fat concentration in an adipose tissue biopsy. The FFQ was specially designed for use in a cohort of Seventh-day Adventists. In preparation for a large cohort study investigating the effect of diet on risk of colon, prostate and breast cancer. METHODS The association of adipose tissue fatty acids and dietary fat intake was assessed in 49 black and 72 white Seventh-day Adventists subjects using 8 different 24-hour recalls, a 200-item food frequency questionnaire (FFQ) and adipose tissue biopsies from each subject. RESULTS Pearson correlation between fatty acids in adipose tissue and dietary intake as assessed by multiple 24-hour recalls were as follows: Linoleic acid: 0.77 in black and 0.71 in white subjects, respectively; Linolenic acid: 0.68 (blacks) and 0.62 (whites); Total Polyunsaturated fat (PUFA): 0.78 (blacks) and 0.70 (whites); Total Monounsaturated fat (MUFA): 0.35 (blacks) and 0.03 (whites); Total Saturated fat (SFA): 0.46 (blacks) and 0.56 (whites). Correlations between fatty acids in adipose tissue and dietary intake as assessed by FFQ were: Linoleic acid: 0.61 (blacks) and 0.52 (whites), respectively; Linolenic acid: 0.29 (blacks) and 0.49 (whites); PUFA: 0.62 (blacks) and 0.53 (whites); MUFA: 0.07 (blacks) and 0.31 (whites), SFA: 0.21 (blacks) and 0.31 (whites). CONCLUSIONS Our study confirms findings of others that 24-hour recalls are valid for assessing dietary intake of different types of fat. The FFQ we developed and used in this study gave reasonably valid measures of fatty acid intake in our population and is thus suitable for use in large cohort studies. It had validity comparable to that observed for other FFQs.

Comparing biological measurements of vitamin C, folate, alpha-tocopherol and carotene with 24-hour dietary recall information in nonhispanic blacks and whites.

PURPOSE To assess intake of several vitamins in preparation for a large cohort study investigating the effect of diet on risk of colon and prostate cancer. METHODS The dietary intake of several vitamins were assessed using eight different 24-hour recalls and a 200-item food frequency questionnaire (FFQ) from each subject. Participants also attended a clinic where blood was drawn and body composition, weight, height, and blood pressure were measured. A total of 97 black and 96 nonhispanic white subjects participated. The levels of alpha-tocopherol, carotene, folate, and vitamin C in the blood were correlated with the dietary intakes as measured by both 24-hour recalls and FFQ. RESULTS Correlations between blood levels and energy-adjusted dietary intake assessed by 24-hour recalls (with supplements) were as follows: carotene (adjusted for serum cholesterol): 0.47 and 0.55 in black and white subjects, respectively; alpha-tocopherol (adjusted for serum cholesterol): 0.61 (blacks) and 0.50 (whites); vitamin C: 0.22 (blacks) and 0.17 (whites); folate: 0.54 (blacks) and 0.55 (whites). Correlations between blood levels and FFQ indices were smaller in magnitude: 0.34 and 0.28 for carotene in black and white subjects, respectively, 0.37 and 0.56 for alpha-tocopherol (adjusted for serum cholesterol), 0.20 and 0.03 for vitamin C and 0.24 and 0.32 for folate. CONCLUSIONS The correlations observed were generally of modest to moderate size and were similar to or larger than those reported by others. This is despite variations in absorption, metabolism, and excretion of the vitamins and suggests that both the 24-hour recalls and the FFQ contain valid information.

Effects of walnut consumption on cognitive performance in young adults.

Walnuts contain a number of potentially neuroprotective compounds like vitamin E, folate, melatonin, several antioxidative polyphenols and significant amounts of n-3 α-linolenic fatty acid. The present study sought to determine the effect of walnuts on verbal and non-verbal reasoning, memory and mood. A total of sixty-four college students were randomly assigned to two treatment sequences in a crossover fashion: walnuts-placebo or placebo-walnuts. Baseline data were collected for non-verbal reasoning, verbal reasoning, memory and mood states. Data were collected again after 8 weeks of intervention. After 6 weeks of washout, the intervention groups followed the diets in reverse order. Data were collected once more at the end of the 8-week intervention period. No significant increases were detected for mood, non-verbal reasoning or memory on the walnut-supplemented diet. However, inferential verbal reasoning increased significantly by 11.2 %, indicating a medium effect size (P = 0.009; d = 0.567). In young, healthy, normal adults, walnuts do not appear to improve memory, mood or non-verbal reasoning abilities. However, walnuts may have the ability to increase inferential reasoning.

Vegan lifestyle behaviors. An exploration of congruence with health-related beliefs and assessed health indices

This study aimed to investigate health belief as a major motive for diet and lifestyle behaviors of 100 vegans in the United States; and to determine congruence with selected health and nutrition outcomes. Response data from an administered questionnaire was analyzed. Statistical analyses determined the most common factors influencing diet choice; the number of vegans practicing particular lifestyle behaviors; body mass index; and prevalence of self-reported chronic disease diagnoses. Nutrient intakes were analyzed and assessed against Dietary Reference Intakes. Health was the most reported reason for diet choice (47%). In the health belief, animal welfare, and religious/other motive categories, low percentages of chronic disease diagnoses were reported: 27%, 11%, and 15%, respectively. There were no significant differences in health behaviors and indices among vegan motive categories, except for product fat content choices. Within the entire study population, health-related vegan motive coincided with regular exercise; 71% normal BMI (mean=22.6); minimal alcohol and smoking practices; frequently consumed vegetables, nuts, and grains; healthy choices in meal types, cooking methods, and low-fat product consumption; and adequate intakes for most protective nutrients when compared to reference values. But incongruence was found with 0% intake adequacy for vitamin D; and observation of excessive sodium use.

The effect of dietary walnuts compared to fatty fish on eicosanoids, cytokines, soluble endothelial adhesion molecules and lymphocyte subsets: a randomized, controlled crossover trial ☆

We tested the hypothesis that walnut consumption can exert effects on markers of inflammation and endothelial activation similar to those produced by fish consumption. In a crossover dietary intervention trial, 25 normal to mildly hyperlipidemic men and women were randomly assigned to one of three isoenergetic diets: a walnut diet incorporating 42.5 g of walnuts per 10.1 mJ 6 times per week (1.8% of energy n-3 fat); a fish diet providing 113 g of fatty fish per 10.1 mJ 2 times per week (0.8% of energy n-3 fat), or a control diet (no nuts or fish, 0.4% of energy n-3 fat) for 4 weeks on each diet. Both the walnut and fish diets inhibited circulating concentrations of prostaglandin E metabolite (PGEM) and 11-dehydro thromboxane B2, but demonstrated no effect on blood interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α¯ (TNF-α¯), and C-reactive protein (CRP) or the number of circulating lymphocyte subsets. On the walnut diet the proportion of plasma phospholipid α¯-linolenic acid (ALA) increased 140% and arachidonic acid (AA) decreased 7% compared to both the control and fish diets. The proportion of plasma phospholipid eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) increased about 200% and 900% respectively on the fish diet relative to either the control or walnut diet. The walnut diet inhibited E-selectin by 12.7% relative to the fish diet, and the fish diet inhibited secretory intercellular adhesion molecule-1 (s-ICAM-1) by 4.5% relative to the control diet. Both walnuts and fish in commonly consumed amounts may have modest albeit distinct effects on circulating adhesion molecules.

The Association between Ambient Fine Particulate Air Pollution and Lung Cancer Incidence: Results from the AHSMOG-2 Study.

Background: There is a positive association between ambient fine particulate matter ≤ 2.5 μm in aerodynamic diameter (PM2.5) and incidence and mortality of lung cancer (LC), but few studies have assessed the relationship between ambient PM2.5 and LC among never smokers. Objectives: We assessed the association between PM2.5 and risk of LC using the Adventist Health and Smog Study-2 (AHSMOG-2), a cohort of health conscious nonsmokers where 81% have never smoked. Methods: A total of 80,285 AHSMOG-2 participants were followed for an average of 7.5 years with respect to incident LC identified through linkage with U.S. state cancer registries. Estimates of ambient air pollution levels at participants’ residences were obtained for 2000 and 2001, the years immediately prior to the start of the study. Results: A total of 250 incident LC cases occurred during 598,927 person-years of follow-up. For each 10-μg/m3 increment in PM2.5, adjusted hazard ratio (HR) with 95% confidence interval (CI) for LC incidence was 1.43 (95% CI: 1.11, 1.84) in the two-pollutant multivariable model with ozone. Among those who spent > 1 hr/day outdoors or who had lived 5 or more years at their enrollment address, the HR was 1.68 (95% CI: 1.28, 2.22) and 1.54 (95% CI: 1.17, 2.04), respectively. Conclusion: Increased risk estimates of LC were observed for each 10-μg/m3 increment in ambient PM2.5 concentration. The estimate was higher among those with longer residence at enrollment address and those who spent > 1 hr/day outdoors. Citation: Gharibvand L, Shavlik D, Ghamsary M, Beeson WL, Soret S, Knutsen R, Knutsen SF. 2017. The association between ambient fine particulate air pollution and lung cancer incidence: results from the AHSMOG-2 study. Environ Health Perspect 125:378–384; http://dx.doi.org/10.1289/EHP124Citation: Gharibvand L, Shavlik D, Ghamsary M, Beeson WL, Soret S, Knutsen R, Knutsen SF. 2017. The association between ambient fine particulate air pollution and lung cancer incidence: results from the AHSMOG-2 study. Environ Health Perspect 125:378–384; http://dx.doi.org/10.1289/EHP124

Predictors of Delayed-Stage Colorectal Cancer: Are We Neglecting Critical Demographic Information?

PURPOSE We sought to distinguish roles of demographic variables and bowel segments as predictors of delayed versus early stage colorectal cancer in California. METHODS Demographic and anatomic variables for 66,806 colorectal cancers were extracted from the California Cancer Registry for 2004-2008 and analyzed using logistic regression as delayed versus early stage. RESULTS Odds ratios (OR) for binary stage categories comparing age <40 (OR=2.58; 95% CI=2.26-2.94), 40-49 (1.71; 95%=1.60-1.83) and 75+ (1.05; 1.02-1.09) relative to 50-74 years were computed. Compared with non-Hispanic whites, ORs for stage categories were: 1.05; 0.99-1.13 (non-Hispanic blacks), 1.08; 1.02-1.13 (Hispanics), and 1.05; 1.00-1.10 (Asian/others). Females had higher odds of delayed diagnosis (1.09; 1.06-1.13) than males. Descending ORs were measured for successively lower to highest socioeconomic status (SES) quintiles (OR 4:5=1.08; 1.03-1.14, OR 3:5=1.13; 1.08-1.19, OR 2:5=1.18; 1.12- 1.24, and OR 1:5=1.21; 1.14-1.28). CONCLUSIONS Younger and older than age 50-74; females; Hispanic ethnicity; bowel segment contrasts (right/left, proximal/distal, cecum plus appendix/distal), and lower SES were independent predictors of delayed diagnosis. Low SES was the most robust predictor of delayed diagnosis, independent of other covariates. Approximately 77% of delayed diagnoses were in non-Hispanic whites and Asian/others. These findings illustrate the value of a community SES index for targeting egalitarian colorectal cancer screening.

Female Renal Transplant Recipients Potentially at Increased Risk of Fatal Coronary Heart Disease Associated with Ambient Air Pollutants

Background: There is increasing evidence that specific ambient air pollutants are associated with coronary heart disease (CHD) morbidity and mortality and risks may differ by gender. Renal transplant recipients have previously been identified as a potentially sensitive subgroup. The purpose of this study was to evaluate the possible effect of long-term ambient pollutant ozone (O3) and particulate matter (PM10) on risk of coronary heart disease (CHD) mortality and determine if gender differences exist among renal transplant recipients. Methods: This retrospective cohort study included 38,101 (22,276 males and 15,825 females) subjects identified through the US Renal Data System (USRDS), which included adult, renal transplant recipients, transplanted between 1997-2003, and living in the continental U.S.A. Air pollution statistics collected over the national ambient monitoring network, were extracted from US Environmental Protection Agency (EPA) Air Quality System (AQS). Mean monthly concentrations of O3, and PM10 calculated from ambient monitoring data and interpolated to ZIP code centroids according to residence of the subjects. Cox proportional hazard models used to estimate effect of air pollutants on mortality (CHD) risks, while adjusting for potential confounders. All analyses conducted were gender-specific. Results: In both the age-and multivariable adjusted models, there was a significant association between risk of fatal CHD and O3 for females (HR=1.56, 95%CI: 1.06-2.30), no significant association found for males. O3 displayed the strongest association with CHD mortality among females with a HR=1.57 (95%CI: 1.07-2.30) after adjustment for PM10 in the two pollutant multivariable model. For both pollutants and across all models, females consistently experienced greater risk than males. No significant association identified for PM10 for either gender. Conclusions: The findings from our study have potential implications for policies and regulations of air pollution. Gender, as a higher risk category, may be relevant in developing individual CHD risk reduction strategies for renal transplant recipients to ultimately improve long-term survival.