Nitin Shivappa

Association of a Dietary Inflammatory Index With Inflammatory Indices and Metabolic Syndrome Among Police Officers

Objectives:To determine whether the dietary inflammatory index (DII) is associated with inflammatory or metabolic biomarkers and metabolic syndrome (MetSyn) among police officers. Methods:Cross-sectional data from the Buffalo Cardio-Metabolic Occupational Police Stress study were derived from saliva and fasting blood samples, anthropometric measurements, long-term shiftwork histories, and demographic, stress/depression, and food frequency questionnaires (FFQs). Metabolic syndrome was defined using standard criteria. Results:Officers in DII quartiles 2 to 4 were more likely to exceed a threshold of 3.0 mg/L for C-reactive protein (odds ratio [OR] = 1.88; 95% confidence interval [95% CI] = 1.02 to 3.45; OR = 2.17; 95% CI = 1.19 to 3.95; OR = 1.57; 95% CI = 0.85 to 2.88, respectively) compared with quartile 1. The glucose intolerance component of MetSyn was more prevalent among officers in DII quartile 4 than among those in quartile 1 (OR = 2.03; 95% CI = 1.08 to 3.82). Conclusions:A pro-inflammatory diet was associated with elevated CRP and with the glucose intolerance component of MetSyn.

Dietary inflammatory index is related to asthma risk, lung function and systemic inflammation in asthma

Asthma prevalence has increased in recent years, and evidence suggests that diet may be a contributing factor. Increased use of processed foods has led to a decrease in diet quality, which may be creating a pro‐inflammatory environment, thereby leading to the development and/or progression of various chronic inflammatory diseases and conditions. Recently, the dietary inflammatory index (DII) has been developed and validated to assess the inflammatory potential of individual diets.

Dietary Inflammatory Index and Risk of Colorectal Cancer in the Iowa Women's Health Study

Background: Colorectal cancer, the third most common cancer in the United States, has a natural history that usually encompasses several decades. Dietary components have been implicated in the etiology of colorectal cancer, perhaps through their effect on inflammation. Methods: We examined the ability of the dietary inflammatory index (DII) to predict colorectal cancer in the Iowa Womens Health Study. The DII was computed based on dietary intake assessed by a 121-item food frequency questionnaire in this cohort of 34,703 women, ages 55 to 69 years, free of any self-reported prior malignancy at enrollment in 1986. Incident colorectal cancer cases were identified through linkage with the State Health Registry of Iowa (a Surveillance, Epidemiology, and End Results program member). Cox proportional hazards regression was used to estimate HRs. Through the end of 2010, 1,636 incident colorectal cancers were identified, including 1,329 colon and 325 rectal cancers. Results: Multivariable analysis, adjusting for body mass index, smoking status, pack-years of smoking, hormone replacement therapy, education, diabetes, and total energy intake, revealed positive associations between higher DII and colorectal cancer risk [HR for DIIcontinuous: 1.07 per unit increase in DII (corresponding to 0.5 SD unit increase); 95% confidence interval (CI), 1.01–1.13; HR for DIIquintiles: Q5 vs. Q1 = 1.20; 95% CI, 1.01–1.43]. HRs for DII were similar for colon cancer and rectal cancer, though not statistically significant for rectal cancer. Conclusions: These results indicate that a proinflammatory diet, as indicated by higher DII scores, was associated with higher risk of developing colorectal cancer. Impact: Proinflammatory diets are associated with increased risk of colorectal cancer. Cancer Epidemiol Biomarkers Prev; 23(11); 2383–92. ©2014 AACR.

Association between dietary inflammatory index and prostate cancer among Italian men

Previous studies have shown that various dietary components may be implicated in the aetiology of prostate cancer, although the results remain equivocal. The possible relationship of inflammation derived from dietary exposures with prostate cancer risk has not been investigated. We examined the ability of a newly developed dietary inflammatory index (DII) to predict prostate cancer risk in a case-control study conducted in Italy between 1991 and 2002. A total of 1294 patients aged < 75 years with incident, histologically confirmed carcinoma of the prostate served as cases. A total of 1451 subjects aged < 75 years who were admitted to the same hospitals as cases for a wide spectrum of acute, non-neoplastic conditions served as controls. The DII was computed based on dietary intake assessed using a previously validated seventy-eight-item FFQ. Logistic regression models were used to estimate multivariable OR adjusted for age, study centre, years of education, social class, BMI, smoking status, family history of prostate cancer and total energy intake. Men with higher DII scores had a higher risk of prostate cancer when analysed using the DII as both continuous (OR 1.06, 95% CI 1.00, 1.13) and categorical, i.e., compared with men in the lowest quartile of the DII, men in the third and fourth quartiles were at elevated risk (OR(Quartile 3 v. 1) 1.32, 95% CI 1.03, 1.69 and OR(Quartile 4 v. 1) 1.33, 95% CI 1.01, 1.76; P trend= 0.04). These data suggest that a pro-inflammatory diet, as indicated by the increasing DII score, is a risk factor of prostate cancer in Italian men.

Dietary Inflammatory Index and Incidence of Cardiovascular Disease in the PREDIMED Study

Previous studies have reported an association between a more pro-inflammatory diet profile and various chronic metabolic diseases. The Dietary Inflammatory Index (DII) was used to assess the inflammatory potential of nutrients and foods in the context of a dietary pattern. We prospectively examined the association between the DII and the incidence of cardiovascular disease (CVD: myocardial infarction, stroke or cardiovascular death) in the PREDIMED (Prevención con Dieta Mediterránea) study including 7216 high-risk participants. The DII was computed based on a validated 137-item food frequency questionnaire. Multivariate-adjusted hazard ratios (HR) and 95% confidence intervals of CVD risk were computed across quartiles of the DII where the lowest (most anti-inflammatory) quartile is the referent. Risk increased across the quartiles (i.e., with increasing inflammatory potential): HRquartile2 = 1.42 (95%CI = 0.97–2.09); HRquartile3 = 1.85 (1.27–2.71); and HRquartile4 = 1.73 (1.15–2.60). When fit as continuous the multiple-adjusted hazard ratio for each additional standard deviation of the DII was 1.22 (1.06–1.40). Our results provide direct prospective evidence that a pro-inflammatory diet is associated with a higher risk of cardiovascular clinical events.

Dietary inflammatory index and risk of pancreatic cancer in an Italian case–control study

Previous studies have shown that various dietary components may be implicated in the aetiology of pancreatic cancer. However, the possible relationship between diet-related inflammation and the risk of pancreatic cancer has not yet been investigated. We examined the ability of a newly developed literature-derived dietary inflammatory index (DII) to predict the risk of pancreatic cancer in a case-control study conducted in Italy between 1991 and 2008. This included 326 incident cases and 652 controls admitted to the major teaching and general hospitals for non-neoplastic diseases, frequency-matched to cases by study centre, sex and age. The DII was computed based on dietary intake assessed using a validated and reproducible seventy-eight-item FFQ. Logistic regression models were used to estimate multivariable OR adjusted for age, sex, study centre, education, BMI, smoking status, alcohol drinking and history of diabetes. Energy adjustment was performed using the residual method. Subjects with higher DII scores (i.e., representing a more pro-inflammatory diet) had a higher risk of pancreatic cancer, with the DII being used as both a continuous variable (ORcontinuous 1.24, 95% CI 1.11, 1.38) and a categorical variable (i.e., compared with the subjects in the lowest quintile of the DII, those in the second, third, fourth and fifth quintiles had, respectively, OR(quintile2 v. 1) 1.70, 95% CI 1.02, 2.80; OR(quintile3 v. 1) 1.91, 95% CI 1.16, 3.16; OR(quintile4 v. 1) 1.98, 95% CI 1.20, 3.27; OR(quintile5 v. 1) 2.48, 95% CI 1.50, 4.10; P trend= 0.0015). These data suggest that a pro-inflammatory diet increases the risk of pancreatic cancer.

Dietary inflammatory index and anthropometric measures of obesity in a population sample at high cardiovascular risk from the PREDIMED (PREvención con DIeta MEDiterránea) trial.

The dietary inflammatory index (DII) is a new tool to assess the inflammatory potential of the diet. In the present study, we aimed to determine the association between the DII and BMI, waist circumference and waist:height ratio (WHtR). We conducted a cross-sectional study of 7236 participants recruited into the PREvención con DIeta MEDiterránea trial. Information from a validated 137-item FFQ was used to calculate energy, food and nutrient intakes. A fourteen-item dietary screener was used to assess adherence to the Mediterranean diet (MeDiet). Sex-specific multivariable linear regression models were fitted to estimate differences (and 95 % CI) in BMI, waist circumference and WHtR across the quintiles of the DII. All nutrient intakes, healthy foods and adherence to the MeDiet were higher in the quintile with the lowest DII score (more anti-inflammatory values) except for intakes of animal protein, saturated fat and monounsaturated fat. Although an inverse association between the DII and total energy was apparent, the DII was associated with higher average BMI, waist circumference and WHtR after adjusting for known risk factors. The adjusted difference in the WHtR for women and men between the highest and lowest quintiles of the DII was 1·60 % (95 % CI 0·87, 2·33) and 1·04 % (95 % CI 0·35, 1·74), respectively. Pro-inflammatory scores remained associated with obesity after controlling for the effect that adherence to a MeDiet had on inflammation. In conclusion, the present study shows a direct association between the DII and indices of obesity, and supports the hypothesis that diet may have a role in the development of obesity through inflammatory modulation mechanisms.

Dietary Inflammatory Index and Incidence of Cardiovascular Disease in the SUN Cohort.

Background Diet is known to play a key role in atherogenesis and in the development of cardiovascular events. Dietary factors may mediate these processes acting as potential modulators of inflammation. Potential Links between inflammatory properties of diet and the occurrence of cardiovascular events have not been tested previously. Objective We aimed to assess the association between the dietary inflammatory index (DII), a method to assess the inflammatory potential of the diet, and incident cardiovascular disease. Methods In the prospective, dynamic SUN cohort, 18,794 middle-aged, Spanish university graduates were followed up for 8.9 years (median). A validated 136-item food-frequency questionnaire was used to calculate the DII. The DII is based on scientific evidence about the relationship between diet and inflammatory biomarkers (C-reactive protein, IL-1β, IL-4, IL-6, IL-10 and TNF-α). Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between the DII and incident cardiovascular disease (myocardial infarction, stroke or cardiovascular death). Results The risk for cardiovascular events progressively increased with each increasing quartile of DII (ptrend = 0.017). The multivariable-adjusted HR for participants in the highest (most pro-inflammatory) vs. the lowest quartile of the DII was 2.03 (95% CI 1.06–3.88). Conclusions A pro-inflammatory diet was associated with a significantly higher risk for developing cardiovascular events.

Dietary inflammatory index scores differ by shift work status: NHANES 2005 to 2010.

Objective: Shift workers are affected by diet- and inflammation-related diseases, including cardiovascular disease, diabetes, and cancer. We examined a dietary inflammatory index (DII) in relation to shift work from the National Health and Nutrition Examination Survey data (2005 to 2010). Methods: The DII was calculated using data from a 24-hour dietary recall. Shift work categories included day workers, evening/night shift workers, or rotating shift workers. General linear models were fit to examine the relationship between shift work and adjusted mean DII values. Results: Among all shift workers and specifically rotating shift workers, higher (ie, more pro-inflammatory) mean DII scores (1.01 and 1.07 vs 0.86; both P ⩽ 0.01) were observed compared with day workers. Women tended to express strong evening/night shift effects. Conclusions: More proinflammatory diets observed among shift workers may partially explain increased inflammation-related chronic disease risk observed in other studies among shift workers compared with their day-working counterparts.

Dietary inflammatory index and telomere length in subjects with a high cardiovascular disease risk from the PREDIMED-NAVARRA study: cross-sectional and longitudinal analyses over 5 y

BACKGROUND Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening. OBJECTIVE This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention. DESIGN This was a prospective study of 520 participants at high cardiovascular disease risk (mean ± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire. RESULTS Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score ≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025). CONCLUSIONS This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639.