Fred Tabung, PhD(c), MSPH Department of Epidemiology and Biostatistics Cancer Prevention and Control Program Arnold School of Public Health, USC 4th Annual USC Center for Research in Nutrition and Health Disparities, Annual Symposium March 21, 2014 Literature-derived population-based index to assess the inflammatory potential of diet Developed from published associations of 45 dietary factors (macronutrients, micronutrients and foods) and six inflammatory biomarkers Assesses the inflammatory potential of an individual’s diet on a continuum from maximally antiinflammatory to maximally pro-inflammatory Validated using data on hsCRP and 24-hour dietary recall interviews (24HR) and 7-day dietary recalls (7DDR) CANCER PREVENTION & CONTROL PROGRAM Shivappa N, Steck SE, Hurley TG, Hussey JR, Hebert JR. Designing and Developing a Literature-derived, Populationbased Dietary Inflammatory Index. Public Health Nutr 2013; S1368980013002115 [pii]; 10.1017/S1368980013002115 [doi]:1-8. Shivappa N, Steck SE, Hurley TG, Hussey JR, Ma Y, Ockene IS, Tabung FK, Hebert JR. A Population-based Dietary Inflammatory Index Predicts Levels of C-Reactive Protein in the Seasonal Variation of Blood Cholesterol Study (SEASONS). Public Health Nutr 2013; S1368980013002565 [pii]; 10.1017/S1368980013002565 [doi]:1-9. CANCER PREVENTION & CONTROL PROGRAM Food group (medium servings/day) Fruits Q1 (-7.055, <3.136) (healthiest) 2.71 2.04 1.85 1.73 Q5 (1.953, 5.636) (least healthy) 1.73 Q2 (-3.136, Q3 (-1.995, <<-1.995) 0.300) Q4 (-0.300, <1.953) Vegetables 3.15 2.30 2.12 2.00 2.00 Combo Fruit/Veg 5.86 4.34 3.97 3.73 3.73 Fish 0.07 0.07 0.07 0.07 0.07 Red meat 0.63 0.73 0.74 0.76 0.76 Poultry 0.44 0.40 0.38 0.38 0.38 Soy 0.08 0.02 0.02 0.02 0.02 Nuts 0.26 0.20 0.18 0.17 0.17 Combo Nut/soy 0.34 0.22 0.20 0.18 0.18 Grains 5.89 4.69 4.55 4.47 4.47 Whole Grain 1.73 1.24 1.17 1.12 1.12 Milk 0.97 0.88 0.80 0.71 0.71 Dairy 2.30 2.06 1.92 1.76 1.76 CANCER PREVENTION & CONTROL PROGRAM Actual intake data in the WHI CT-OS About 65,000 American women are projected to be diagnosed with colorectal cancer (CRC) in 2014 3rd most commonly diagnosed cancer in women after breast and lung cancers Adherence to dietary patterns such as DASH, HEI and Med diet, has been shown to be associated with reduced CRC risk Evidence of an influence of inflammation on CRC: Patients with ulcerative colitis and Crohn's disease have an increased risk of developing CRC Reduced risk of colon cancer with use of aspirin or other NSAIDs CANCER PREVENTION & CONTROL PROGRAM To utilize the DII to evaluate the association of the inflammatory potential of diet with risk of colorectal cancer in postmenopausal women CANCER PREVENTION & CONTROL PROGRAM DII calculated from baseline FFQs (1993-1998) Both OS and CT data used Categorized into quintiles Participants followed until incident colorectal cancer or September 30, 2010 Colorectal cancer cases ascertained through a centralized physician adjudication process (n=1,922) CANCER PREVENTION & CONTROL PROGRAM Excluded from analysis: ◦ Women who reported previous CRC at baseline or missing previous CRC status at baseline ◦ Women with implausible reported total energy intake values (≤600 kcal/d or ≥ 5000 kcal/d) or extreme body mass index (BMI) values (≤15kg/m2or ≥ 50kg/m2) Multiple covariate-adjusted Cox proportional hazards (PH) regression models used to calculate hazard ratios (HR) for: ◦ colorectal cancer ◦ colon cancer proximal colon cancer distal colon cancer ◦ rectal cancer CANCER PREVENTION & CONTROL PROGRAM Lowest DII quintile (most anti-inflammatory diet) was the referent for all models Potential effect modification by waist-to-hip ratio, waist circumference, BMI, and NSAID use, investigated by stratifying on these covariates in the Cox PH models Tests of linear trend adjusted for covariates, computed by assigning the median value of each quintile to each participant in the quintile Sensitivity analyses- exclusion of CRC cases that occurred within 3 years from baseline Analyses by stage of CRC at diagnosis (localized, regional and distant) CANCER PREVENTION & CONTROL PROGRAM Total energy intake Age BMI Race/ethnicity Educational level Physical activity Family history of colorectal cancer Diabetes Hypertension Arthritis History of colonoscopy History of occult blood tests NSAID use Category & duration of estrogen use Category & duration of combined estrogen & progesterone use DM arm, HRT arm, and CaD arm CANCER PREVENTION & CONTROL PROGRAM Risk of colorectal cancer across quintiles of the DII Q1 (-7.055, <3.136) (healthiest) Referent Colorectal cancer Colorectal cancer cases, 1922 Colon cancer Colon cancer cases, 1560 Proximal colon Proximal colon cancer cases, 1034 CANCER PREVENTION & CONTROL PROGRAM HR (95%CI) Q5 (1.953, 5.636) (least healthy) HR (95%CI) Ptrend 1.00 0.98 (0.84, 1.14) 1.22 (1.05, 1.43) 0.02 365 (19.0%) 360 (18.7%) 435 (22.6%) 1.00 0.98 (0.83, 1.15) 1.23 (1.03, 1.47) 299 (19.2%) 289 (18.5%) 346 (22.2%) 1.00 0.98 (0.79, 1.20) 1.35 (1.09, 1.67) 193 (18.7%) 181 (17.5%) 229 (22.2%) Q3 (-1.995, <0.300) 0.02 0.01 HRs were strengthened when CRC cases that developed within 3 years from baseline were excluded, ◦ e.g. HR Q5vsQ1 for colon cancer: 1.36 (1.11, 1.66), Ptrend=0.003 HRs for CRC differed by category of NSAID use: ◦ Pinteraction=0.26 ◦ Non-NSAID users: 1.31 (1.05, 1.65)Q5vsQ1, Ptrend=0.03 ◦ NSAID users: 1.11 (0.89, 1.38) Q5vsQ1, Ptrend=0.61 No significant association with: ◦ Distal colon cancer ◦ Rectal cancer ◦ CRC stage at diagnosis CANCER PREVENTION & CONTROL PROGRAM Study limited to postmenopausal women FFQ measurement error Diet assessment at only one time point CANCER PREVENTION & CONTROL PROGRAM Consumption of pro-inflammatory diets increases the risk of colorectal cancer in older women, especially colon cancer located in the proximal colon Consumption of pro-inflammatory diets increases the risk of colorectal cancer in older women not regularly taking NSAIDs CANCER PREVENTION & CONTROL PROGRAM Longitudinal Changes in Diet-related Inflammation and Risk of Cancer in Women An assessment of the inflammatory potential of diet over time in the Women’s Health Initiative Changes in the DII over time and risk of colorectal cancer in women CANCER PREVENTION & CONTROL PROGRAM Chair: Susan E. Steck USC Dept. of EPID/BIOS and Cancer Prevention and Control Program Members: Yunsheng Ma Angela D. Liese UMass Medical School USC Dept. of EPID/BIOS and Center for Nutrition & Health Disparities Jiajia Zhang USC Dept. of Epidemiology & Biostatistics James R. Hebert USC Dept. of EPID/BIOS and Cancer Prevention and Control Program CANCER PREVENTION & CONTROL PROGRAM Lifang Hou Northwestern Univ. Feinberg School of Medicine Bette Caan Kaiser Permanente Division of Research Karen K. Johnson Univ. of Tennessee Health Science Center Yasmin Mossavar-Rahmani Albert Einstein College of Medicine Jean Wactawski-Wende SUNY Dept. of Social and Preventive Medicine Judith K. Ockene UMass Medical School Nitin Shivappa USC Dept. of EPID/BIOS and Cancer Prevention and Control Program CANCER PREVENTION & CONTROL PROGRAM Mr. Tabung was supported by an NIH F31 National Research Service Predoctoral Award, a USC SPARC grant and a fellowship from the USC Center for Colon Cancer Research Drs. Steck and Zhang were supported by the Prevent Cancer Foundation Living in Pink grant Dr. Hébert was supported by an Established Investigator Award in Cancer Prevention and Control from the Cancer Training Branch of the National Cancer Institute (K05 CA136975). Funding for DII development was provided by the CPCP The WHI program is funded by the National Heart, Lung, and Blood Institute, National Institutes of Health, U.S. Department of Health and Human Services through contracts HHSN268201100046C, HHSN268201100001C, HHSN268201100002C, HHSN268201100003C, HHSN268201100004C, and HHSN271201100004C. CANCER PREVENTION & CONTROL PROGRAM