Association between the dietary inflammatory index and all-cause mortality in colorectal cancer long-term survivors

Post-diagnosis dietary factors, supplement use and colorectal cancer prognosis: A Global Cancer Update Programme (CUP Global) systematic literature review and meta-analysis

The role of diet in colorectal cancer prognosis is not well understood and specific lifestyle recommendations are lacking. We searched for randomised controlled trials (RCTs) and longitudinal observational studies on post-diagnosis dietary factors, supplement use and colorectal cancer survival outcomes in PubMed and Embase from inception until 28th February 2022. Random-effects dose-response meta-analyses were conducted when at least three studies had sufficient information. The evidence was interpreted and graded by the CUP Global independent Expert Committee on Cancer Survivorship and Expert Panel. Five RCTs and 35 observational studies were included (30,242 cases, over 8700 all-cause and 2100 colorectal cancer deaths, 3700 progression, recurrence, or disease-free events). Meta-analyses, including 3-10 observational studies each, were conducted for: whole grains, nuts/peanuts, red and processed meat, dairy products, sugary drinks, artificially sweetened beverages, coffee, alcohol, dietary glycaemic load/index, insulin load/index, marine omega-3 polyunsaturated fatty acids, supplemental calcium, circulating 25-hydroxyvitamin D (25[OH]D) and all-cause mortality; for alcohol, supplemental calcium, circulating 25(OH)D and colorectal cancer-specific mortality; and for circulating 25(OH)D and recurrence/disease-free survival. The overall evidence was graded as 'limited'. The inverse associations between healthy dietary and/or lifestyle patterns (including diets that comprised plant-based foods), whole grains, total, caffeinated, or decaffeinated coffee and all-cause mortality and the positive associations between unhealthy dietary patterns, sugary drinks and all-cause mortality provided 'limited-suggestive' evidence. All other exposure-outcome associations provided 'limited-no conclusion' evidence. Additional, well-conducted cohort studies and carefully designed RCTs are needed to develop specific lifestyle recommendations for colorectal cancer survivors.

The relationship between dietary inflammatory potential and cancer outcomes among cancer survivors: A systematic review and meta-analysis of cohort studies

Cancer remains the second leading cause of death globally. Chronic inflammatory environments promote the growth of tumors, and the intake of certain food items can increase systemic inflammation. This study examined the relationship between the inflammatory potential of diet, measured by the Dietary Inflammatory Index (DII), and recurrence, all-cause, and cancer-specific mortality among cancer survivors. Web of Science, Medline, CINHAL, and PsycINFO databases were searched in April 2022. Two independent reviewers screened all searches. Of the 1,443 studies, 13 studies involving 14,920 cancer survivors passed all the screening stages. Three studies reported cancer recurrence, 12 reported all-cause mortality, and six reported cancer-specific mortality. Seven studies calculated DII from pre-diagnosis diets, five from post-diagnosis diets, and one from both pre-and post-diagnosis diets. A random-effects model meta-analysis showed that high DII was not associated with an increased risk of recurrence (HR = 1.09, 95 % CI = 0.77, 1.54, n = 4) and all-cause (HR = 1.08, 95 % CI = 0.99, 1.19, n = 14) and cancer-specific mortality (H = 1.07, 95 % CI = 0.92, 1.25, n = 6). Analysis by the timing of dietary assessment showed that only post-diagnosis DII was associated with an increased risk of all-cause mortality (HR = 1.34, 95 % CI = 1.05, 1.72, n = 6) by 34 %; however, cancer type did not modify these associations. The quality of the study assessed using the Newcastle Ottawa Scale indicated all but one studies were good. The risk of all-cause mortality among cancer survivors could be reduced by consuming more anti-inflammatory diets after cancer diagnosis.

Post-Diagnosis Dietary Patterns among Cancer Survivors in Relation to All-Cause Mortality and Cancer-Specific Mortality: A Systematic Review and Meta-Analysis of Cohort Studies

The role of overall diet on longevity among cancer survivors (CS) needs further elucidation. We performed a systematic review of the literature and a meta-analysis of related cohort studies published up to October 2022 investigating post-diagnosis a priori (diet quality indices) and a posteriori (data-driven) dietary patterns (DPs) in relation to all-cause and cancer-specific mortality. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using random-effects meta-analyses comparing highest versus lowest categories of adherence to DPs. We assessed heterogeneity and risk of bias in the selected studies. A total of 19 cohort studies with 38,846 adult CS, some assessing various DPs, were included in the meta-analyses. Higher adherence to a priori DPs was associated with lower all-cause mortality by 22% (HR = 0.78, 95% CI: 0.73-0.83, I2 = 22.6%) among all CS, by 22% (HR = 0.78, 95% CI: 0.73-0.84, I2 = 0%) among breast CS and by 27% (HR = 0.73, 95% CI: 0.62-0.86, I2 = 41.4%) among colorectal CS. Higher adherence to a "prudent/healthy" DP was associated with lower all-cause mortality (HR = 0.79, 95% CI: 0.64-0.97 I2 = 49.3%), whereas higher adherence to a "western/unhealthy" DP was associated with increased all-cause mortality (HR = 1.48, 95% CI: 1.26-1.74, I2 = 0%) among all CS. Results for cancer-specific mortality were less clear. In conclusion, higher adherence to a "healthy" DP, either a priori or a posteriori, was inversely associated with all-cause mortality among CS. A "healthy" overall diet after cancer diagnosis could protect and promote longevity and well-being.

Association between dietary inflammatory potential and mortality after cancer diagnosis in the Women's Health Initiative

BACKGROUND

Chronic inflammation is implicated in cancer prognosis and can be modulated by diet. We examined associations between post-diagnosis dietary inflammatory potential and mortality outcomes among post-menopausal women diagnosed with cancer in the Women's Health Initiative (WHI).

METHODS

Energy-adjusted dietary inflammatory index scores (E-DII) were calculated from dietary and supplemental intake data collected on the first food frequency questionnaire following the diagnosis of primary invasive cancer for 3434 women in the WHI. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CIs) for risk of death from any cause, cancer, cardiovascular disease (CVD) and other causes by post-diagnosis quartiles of E-DII. Subgroup analyses by cancer stage and grade were performed.

RESULTS

There were 1156 deaths after a median 13 years of follow-up from the date of a cancer diagnosis. In the multivariable-adjusted analyses, a more anti-inflammatory diet plus supplements after cancer diagnosis was associated with lower all-cause mortality, cancer mortality, CVD mortality and mortality from other causes with HRsQ1vs.Q4 ranging from 0.47 to 0.68 (all P-trends < 0.05). Associations were stronger for cancers diagnosed at more distant stages or moderately differentiated grades.

CONCLUSION

A more anti-inflammatory diet plus supplements after a cancer diagnosis may improve survival for post-menopausal cancer survivors.

Postdiagnostic intake of a more proinflammatory diet is associated with a higher risk of recurrence and all-cause mortality in colorectal cancer survivors

BACKGROUND

The inflammatory potential of the diet has been associated with colorectal cancer (CRC) risk, but its association with CRC prognosis is unclear.

OBJECTIVE

To investigate the inflammatory potential of the diet in relation to recurrence and all-cause mortality among persons diagnosed with stage I to III CRC.

METHODS

Data of the COLON study, a prospective cohort among CRC survivors were used. Dietary intake, 6 mo after diagnosis, was assessed by using a food frequency questionnaire and was available for 1631 individuals. The empirical dietary inflammatory pattern (EDIP) score was used as a proxy for the inflammatory potential of the diet. The EDIP score was created by using reduced rank regression and stepwise linear regression to identify food groups that explained most of the variations in plasma inflammatory markers (IL6, IL8, C-reactive protein, and tumor necrosis factor-α) measured in a subgroup of survivors (n = 421). Multivariable Cox proportional hazard models with restricted cubic splines were used to investigate the relation between the EDIP score and CRC recurrence and all-cause mortality. Models were adjusted for age, sex, BMI, PAL, smoking status, stage of disease, and tumor location.

RESULTS

The median follow-up time was 2.6 y (IQR: 2.1) for recurrence and 5.6 y (IQR: 3.0) for all-cause mortality, during which 154 and 239 events occurred, respectively. A nonlinear positive association between the EDIP score and recurrence and all-cause mortality was observed. For example, a more proinflammatory diet (EDIP score +0.75) compared with the median (EDIP score 0) was associated with a higher risk of CRC recurrence (HR: 1.15; 95% CI: 1.03, 1.29) and all-cause mortality (HR: 1.23; 95% CI: 1.12, 1.35).

CONCLUSIONS

A more proinflammatory diet was associated with a higher risk of recurrence and all-cause mortality in CRC survivors. Further intervention studies should investigate whether a switch to a more anti-inflammatory diet improves CRC prognosis.

Dietary inflammatory index, and depression and mortality risk associations in U.S. adults, with a special focus on cancer survivors

Introduction

A higher risk for depression and mortality is associated with the inflammatory potential of diet measured through the Dietary Inflammatory Index (DII). The roles of DII in the risk of depression and death in cancer survivors were unclear. We aimed to examine the association between energy-adjusted DII (E-DII) score and risk of depression, and mortality using data from the 2007-2018 National Health and Nutrition Examination Survey (NHANES), with a special focus on cancer survivors.

Methods

The 24-h dietary recall interview was used as a basis to calculate the E-DII score and the Patient Health Questionnaire-9 (PHQ-9) was used to measure the depressive outcomes. Logistic regression analyses were performed to determine the association between quartiles of E-DII score and depression. Cox proportional hazard regression and competing risk analyses were used to estimate the risks of quartiles of E-DII score or depression on mortality.

Results

A total of 27,447 participants were included; including 24,694 subjects without cancer and 2,753 cancer survivors. The E-DII score and depression were not distributed differently between the two groups. However, the E-DII scores were positively associated with within each group's depression (all P trend < 0.001) and participants with higher E-DII scores had a higher risk of depression (subjects without cancer: OR_{Q4 vs Q1}: 2.17, 95% CI: 1.75-2.70; cancer survivors: OR_{Q4 vsQ1}: 1.78, 95% CI: 1.09-2.92). The median follow-up time were 87 person-months, a total of 1,701 (4.8%) and 570 (15.2%) all-cause deaths in subjects without cancer and cancer survivors were identified by the end of 2019. The highest E-DII scores quartile was associated with the highest risk of all-cause (HR_{Q4 vsQ1}: 1.90, 95% CI: 1.54-2.35) and cardiovascular disease (CVD) cause death (HR_{Q4 vsQ1}: 2.50, 95% CI: 1.69-2.3.7) in the subjects without cancer. Moreover, participants with depressive symptoms had higher all-cause mortality (HR: 1.29, 95% CI: 1.04-1.59). No significant correlation was found for E-DII scores or depression with all-cause, cancer-cause or CVD-cause mortality in cancer survivors.

Conclusion

Our findings demonstrate that E-DII score was positively associated with depression risk. A higher E-DII score or depressive symptom may increase the risks of all-cause and CVD-cause mortality only among general subjects.

Prognostic role of inflammatory diets in colorectal cancer overall and in strata of tumor-infiltrating lymphocyte levels

BACKGROUND

Certain dietary patterns can elicit systemic and intestinal inflammatory responses, which may influence adaptive anti-tumor immune responses and tumor behavior. We hypothesized that pro-inflammatory diets might be associated with higher colorectal cancer mortality and that the association might be stronger for tumors with lower immune responses.

METHODS

We calculated an empirical dietary inflammatory pattern (EDIP) score in 2829 patients among 3988 incident rectal and colon carcinoma cases in the Nurses' Health Study and Health Professionals Follow-up Study. Using Cox proportional hazards regression analyses, we examined the prognostic association of EDIP scores and whether it might be modified by histopathologic immune reaction (in 1192 patients with available data).

RESULTS

Higher EDIP scores after colorectal cancer diagnosis were associated with worse survival, with multivariable-adjusted hazard ratios (HRs) for the highest versus lowest tertile of 1.41 (95% confidence interval [CI]: 1.13-1.77; Ptrend = 0.003) for 5-year colorectal cancer-specific mortality and 1.44 (95% CI, 1.19-1.74; Ptrend = 0.0004) for 5-year all-cause mortality. The association of post-diagnosis EDIP scores with 5-year colorectal cancer-specific mortality differed by degrees of tumor-infiltrating lymphocytes (TIL; Pinteraction = .002) but not by three other lymphocytic reaction patterns. The multivariable-adjusted, 5-year colorectal cancer-specific mortality HRs for the highest versus lowest EDIP tertile were 1.59 (95% CI: 1.01-2.53) in TIL-absent/low cases and 0.48 (95% CI: 0.16-1.48) in TIL-intermediate/high cases.

CONCLUSIONS

Pro-inflammatory diets after colorectal cancer diagnosis were associated with increased mortality, particularly in patients with absent or low TIL.

Meta-Analysis of the Association between Dietary Inflammatory Index (DII) and Colorectal Cancer

The Dietary Inflammatory Index (DII) was extensively used to examine the inflammatory potential of diet related to colorectal cancer (CRC). This meta-analysis aimed to update the evidence of the association between the DII and CRC across various culture-specific dietary patterns. Literature search was performed through online databases (Scopus, Web of Science, PubMed, and EBSCOHost). Observational studies exploring the association between the DII and CRC, published between 2017 and 2021, were included. The risk ratio (RR) and 95% confidence interval (CI) were separately computed for 12 studies comparing the highest and lowest DII scores and for 3 studies that presented continuous DII scores. A high DII score was associated with a higher risk of CRC (RR:1.16; 95% CI, 1.05–1.27). In the subgroup analysis, significant associations were seen in cohort design (RR: 1.24; 95% CI, 1.06–1.44), those lasting for 10 years or longer (RR: 2.95; 95% CI, 2.47–3.52), and in adjustment factor for physical activity (RR: 1.13; 95% CI, 1.07–1.20). An increase of one point in the DII score elevates the risk of CRC by 1.34 (95% CI: 1.15–1.55) times. The findings call for standardized measurement of the inflammatory potential of diet in future studies to enable the establishment of global guidelines for CRC prevention.

The association between the adapted dietary inflammatory index and colorectal cancer recurrence and all-cause mortality

BACKGROUND & AIMS

The inflammatory potential of the diet has been linked to colorectal cancer (CRC) development and mortality. However, it is unknown whether it is also associated with CRC recurrence. Therefore, the aim of this study was to investigate the associations between the inflammatory potential of the diet and plasma inflammation markers as well as recurrence and all-cause mortality in CRC patients.

METHODS

Data of the Colorectal cancer, Observational, LONgitudinal (COLON) study, a prospective cohort study, was used. Dietary intake, assessed using a semi-quantitative food frequency questionnaire, was available for 1478 patients at diagnosis and for 1334 patients six months after diagnosis. Dietary intake data were used to calculate the adapted dietary inflammatory index (ADII). Data about cancer recurrence and all-cause mortality, were assessed through linkage with the Netherlands Cancer Registry and the Municipal Personal Records Database, respectively. The association between the ADII (continuous) and inflammation markers (Interleukin (IL)6, IL8, IL10, Tumor Necrosis Factor (TNF)α, high sensitivity C-reactive protein (hsCRP) and a summary inflammatory z-score), measured with a multiplex assay using electrochemiluminiscence detection, was assessed using quantile regression analyses. Restricted cubic splines (RCS) analyses and multivariable Cox proportional hazard models were used to explore the relationship between the ADII and CRC outcomes.

RESULTS

During a median follow-up time of 3.2 years (Interquartile range (IQR) 2.0-4.1) for recurrence and 4.8 years (IQR 3.5-5.9) for all-cause mortality, 228 recurrences and 279 deaths occurred. A more pro-inflammatory diet at diagnosis as well as six months after diagnosis was associated with higher levels of TNFα, hsCRP and the summary inflammatory z-score. Results of RCS showed no relationship between the ADII and CRC outcomes at both time points. Also results of the Cox proportional hazard models showed no associations between the ADII at both time points and recurrence (HR (95%CI) 0.98 (0.94-1.04) & 0.96 (0.91-1.02) or all-cause mortality (HR (95%CI) 1.03 (0.98-1.07) & 1.00 (0.95-1.05)).

CONCLUSION

Our study did not show an association between the ADII and recurrence and all-cause mortality in CRC patients. Further research should also take into account molecular tumor subtypes, as the effect of the inflammatory potential of the diet on cancer recurrence and mortality is more likely to be present in tumors with an inflammatory signature.

CLINICAL TRIAL REGISTRY NUMBERS AND WEBSITE

The colon study: NCT03191110; clinical trials.gov.

Dietary Intake in Association with All-Cause Mortality and Colorectal Cancer Mortality among Colorectal Cancer Survivors: A Systematic Review and Meta-Analysis of Prospective Studies

Simple Summary

Given that an extensive range of dietary factors has not been investigated among colorectal cancer (CRC) survivors to date, we carried out a systematic review and meta-analysis to determine the effects of both prediagnostic and postdiagnostic dietary intake on all-cause mortality and CRC-specific mortality among CRC survivors. In total, 45 studies were included in the final analysis of 35 food items, 8 macronutrients, 27 micronutrients, 2 dietary patterns, and 13 dietary indexes in association with all-cause mortality and CRC-specific mortality. We found that an unhealthy dietary pattern increased the risks of both all-cause mortality and CRC-specific mortality. The role of prediagnostic and postdiagnostic intake such as macronutrients and fatty acids could be different in the risk of all-cause mortality. Overall, comprehensive evidence for the effect of substantial numbers of prediagnostic and postdiagnostic dietary items on mortality outcomes is reported in this study.

Abstract

We carried out a systematic review and meta-analysis to determine the effects of both prediagnostic and postdiagnostic dietary intake on all-cause mortality and CRC-specific mortality among CRC survivors. An extensive search of PubMed and Embase was conducted to identify eligible studies. We applied a random-effects model to estimate the pooled relative risks (RRs)/hazard ratios (HRs) and their 95% confidence intervals (CIs). As a result, a total of 45 studies were included in the final analysis. Pooled effect sizes from at least three study populations showed that whole grains and calcium were inversely associated with all-cause mortality, with RRs/HRs (95% CIs) of 0.83 (0.69–0.99) and 0.84 (0.73–0.97), respectively. In contrast, a positive association between an unhealthy dietary pattern and both all-cause mortality (RR/HR = 1.47, 95% CI = 1.05–2.05) and CRC-specific mortality (RR/HR = 1.52, 95% CI = 1.13–2.06) was observed among CRC survivors. In the subgroup analysis by CRC diagnosis, prediagnostic and postdiagnostic dietary intake such as carbohydrates, proteins, lipids, and fiber were observed to have different effects on all-cause mortality. Overall, an unhealthy dietary pattern increased the risks of both all-cause mortality and CRC-specific mortality. The role of prediagnostic and postdiagnostic intake of dietary elements such as macronutrients and fatty acids could be different in the risk of all-cause mortality.

Creation of a Novel Inflammation-Based Score for Operable Colorectal Cancer Patients

Aim

Systemic inflammation has been implicated in the progression of patients with colorectal cancer (CRC). We evaluated the prognostic ability of a comprehensive score based on several inflammatory indexes in operable CRC patients.

Patients and Methods

Between July 2013 and September 2017, this study retrospectively identified 1279 CRC patients receiving radical surgery in Wuhan Union Hospital and randomly assigned them into training (N=921) and validation (N=358) sets. A novel score, the CRC-specific inflammatory index (CSII), was developed from a series of inflammatory indexes significantly associated with survival in patients with CRC. This novel score was then divided into three categories and compared to the well-known systematic inflammatory index (SII) and TNM stage. Finally, a survival nomogram was generated by combining the CSII and other informative clinical features.

Results

The CSII-OS was calculated as 1.110×lg ALRI + 1.082×CAR + 0.792×PI, while CSII-DFS was 1.709×lg ALRI + 1.033×CAR based on multivariable Cox regression analysis. Patients with high CSII experienced a worse OS (HR=23.72, 95% CI, 11.30-49.78, P <0.001) and worse DFS (HR=15.62, 95% CI, 6.95-35.08, P <0.001) compared to those in CRC patients with low CSII. Moreover, ROC analyses showed that the CSII possessed excellent performance (AUC=0.859) in predicting OS and DFS. The AUC of the OS nomogram based on CSII, TNM stage, and chemotherapy was 0.897, while that of the DFS nomogram based on CSII, T stage, and TNM stage was 0.873. High-quality calibration curves in both OS and DFS nomograms were observed. Verification in the validation dataset showed results consistent with those in the training dataset.

Conclusion

The CSII is a CRC-specific prognostic score based on the combination of available inflammatory indexes. High CSII is a strong predictor of worse survival outcomes. The CSII also exhibits better predictive performance compared to SII or TNM stage in operable CRC patients.

Dietary inflammatory index and incidence of and death from primary liver cancer: A prospective study of 103,902 American adults

Chronic inflammation plays an important role in primary liver cancer (PLC) etiology and can be influenced by dietary habits. No prospective study has investigated the association of dietary inflammatory index (DII) with PLC incidence and mortality. Therefore, we used prospective data from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial to fill this gap. The DII was calculated from a validated 137-item food frequency questionnaire in a cohort of 103,902 individuals. Cox regression was used to estimate hazard ratios (HRs) for PLC incidence, and competing risk regression was used to estimate subdistribution HRs (SHRs) for PLC mortality. Restricted cubic spline regression was employed to identify the potential dose-response pattern. A total of 120 PLC cases and 102 PLC deaths were observed during follow-up. Higher DII scores from food and supplement were found to be associated with higher risks of developing PLC (HR_{Tertile 3 vs. 1} 2.05; 95% confidence interval [CI] 1.23-3.41) and death from this disease (SHR_{Tertile 3 vs. 1} 1.97; 95% CI 1.13-3.41). Similar results were obtained for DII score from food only. A nonlinear dose-response pattern was identified for the aforementioned associations (all p_nonlinearity  < 0.05). Overall, a more pro-inflammatory diet, as suggested by higher DII scores, is associated with higher risks of PLC incidence and mortality. These findings indicate that encouraging intake of more anti-inflammatory dietary components and reducing intake of pro-inflammatory components represent an attractive strategy to reduce PLC incidence and mortality.

Long-term anti-inflammatory diet in relation to improved breast cancer prognosis: a prospective cohort study

Inflammation-modulating nutrients and inflammatory markers are established cancer risk factors, however, evidence regarding the association between post-diagnosis diet-associated inflammation and breast cancer survival is relatively sparse. We aimed to examine the association between post-diagnosis dietary inflammatory index (DII®) and risks of all-cause and breast cancer-specific mortality. A total of 1064 female breast cancer survivors in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening (PLCO) Trial prospective cohort, were included in this analysis if they had completed the diet history questionnaire (DHQ). Energy-adjusted DII (E-DIITM) scores were calculated based on food and supplement intake. Cox regression and competing risk models were used to estimate multivariable-adjusted hazards ratios (HRs) and 95% confidence intervals (95% CIs) by E-DII tertile (T) for all-cause and breast cancer-specific mortality. With median follow-up of 14.6 years, there were 296 (27.8%) deaths from all causes and 100 (9.4%) breast cancer-specific death. The E-DII was associated with all-cause mortality (HR T3 vs T1, 1.34; 95% CI, 1.01-1.81; P trend, 0.049, Table 2) and breast cancer mortality (HR T3 vs T1, 1.47; 95% CI, 0.89-2.43; P trend, 0.13; multivariable-adjusted HR for 1-unit increment: 1.10; 95% CI: 1.00-1.22). Non-linear positive dose-response associations with mortality from all causes were identified for E-DII scores (P non-linearity < 0.05). The post-diagnosis E-DII was statistically significantly associated with mortality risk among breast cancer survivors. Long-term anti-inflammatory diet might be a means of improving survival of breast cancer survivors.

The Dietary Inflammatory Index Is Positively Associated with Colorectal Cancer Risk in a Chinese Case-Control Study

Diet may modulate chronic inflammation. The aim of this study is to investigate whether the dietary inflammatory index (DII^®) was associated with the risk of colorectal cancer in a Chinese population. A case-control study was conducted from July 2010 to April 2019, in Guangzhou, China. A total of 2502 eligible cases were recruited along with 2538 age- (5-year interval) and sex-matched controls. Dietary data derived from a validated food frequency questionnaire were used to calculate the energy-adjusted DII (E-DII) scores. Odds ratios (ORs) and 95% confidence intervals (CIs) for colorectal cancer risk were estimated using unconditional logistic regression models. In this study, E-DII scores ranged from -5.96 (the most anti-inflammatory score) to +6.01 (the most pro-inflammatory score). A positive association was found between the E-DII and colorectal cancer risk, with the OR = 1.40 (95% CI 1.16, 1.68; P_trend < 0.01) for the highest E-DII quartile compared with the lowest quartile after adjusting for potential confounders. When stratified based on cancer subsite, sex, body mass index, and smoking status, significant associations were not observed in women or underweight individuals. Results from this study confirmed that a higher E-DII score was associated with an increased risk of colorectal cancer in a Chinese population.

Dietary Inflammatory Index and Non-Communicable Disease Risk: A Narrative Review

There are over 1,000,000 publications on diet and health and over 480,000 references on inflammation in the National Library of Medicine database. In addition, there have now been over 30,000 peer-reviewed articles published on the relationship between diet, inflammation, and health outcomes. Based on this voluminous literature, it is now recognized that low-grade, chronic systemic inflammation is associated with most non-communicable diseases (NCDs), including diabetes, obesity, cardiovascular disease, cancers, respiratory and musculoskeletal disorders, as well as impaired neurodevelopment and adverse mental health outcomes. Dietary components modulate inflammatory status. In recent years, the Dietary Inflammatory Index (DII®), a literature-derived dietary index, was developed to characterize the inflammatory potential of habitual diet. Subsequently, a large and rapidly growing body of research investigating associations between dietary inflammatory potential, determined by the DII, and risk of a wide range of NCDs has emerged. In this narrative review, we examine the current state of the science regarding relationships between the DII and cancer, cardiometabolic, respiratory and musculoskeletal diseases, neurodevelopment, and adverse mental health outcomes. We synthesize the findings from recent studies, discuss potential underlying mechanisms, and look to the future regarding novel applications of the adult and children's DII (C-DII) scores and new avenues of investigation in this field of nutritional research.

Increased Inflammatory Potential of Diet Is Associated with Increased Risk of Bladder Cancer in an Iranian Case-Control Study

Purpose: Various aspects of diet have been implicated to play a role in the etiology of bladder cancer. Studies examining this association have been conducted primarily in Western countries but none in Middle Eastern Countries. Method: We examined the association between the dietary inflammatory index (DII^®) and bladder cancer in an Iranian case-control study. A total of 56 incident cases with a mean age of 60 years and 109 controls with a mean age of 57 years, attending the same hospital as the cases during the same time period, were recruited. The DII is a literature-derived index developed to determine the inflammatory potential of diet and was computed using a validated food frequency questionnaire. Logistic regression was used to estimate odds ratios, with DII fit as continuous and as a dichotomous variable. Results: Multivariate analyses revealed that subjects with higher DII score (>-0.12) are at higher risk of bladder cancer [odds ratio (OR) = 2.46; 95% CI = 1.12-5.41, P value = 0.02)] compared to subjects with lower DII scores (≤-0.12). Stratified results showed stronger association was among current/ex-smokers (OR_{DII (>-0.12/≤-0.12)} = 3.30; 95% CI = 1.07-10.16). Conclusion: These data suggest a pro-inflammatory diet may be a risk factor for bladder cancer among Iranians.

Post-cancer diagnosis dietary inflammatory potential is associated with survival among women diagnosed with colorectal cancer in the Women's Health Initiative

PURPOSE

Dietary factors may influence colorectal cancer (CRC) survival through effects on inflammation. We examined the association between post-CRC diagnosis inflammatory potential of diet and all-cause and cancer-specific mortality in the Women's Health Initiative.

METHODS

The study included 463 postmenopausal women who developed CRC during follow-up and completed a food frequency questionnaire (FFQ), on average 1.7 years after diagnosis. Women were followed from CRC diagnosis until death, censoring, or the end of follow-up in October 2014. Energy-adjusted dietary inflammatory index (E-DII)^® scores were calculated from the FFQ and dietary supplement inventory. Cox proportional hazards models were fitted to estimate multivariable-adjusted HRs and 95% confidence intervals (CIs) for all-cause, total cancer, and CRC-specific mortality with the most pro-inflammatory E-DII scores (tertile 3) as referent.

RESULTS

After a median 11.6 years of follow-up, 162 deaths occurred, including 77 from CRC. Lowest tertile (i.e., most anti-inflammatory) E-DII scores from diet plus supplements were associated with significantly lower all-cause mortality (HR_T1vsT3 = 0.49; 95% CI 0.31-0.79) compared to the most pro-inflammatory E-DII tertile. Modest associations with total cancer mortality or CRC-specific mortality were observed, though 95% CIs included 1.

CONCLUSIONS

Consuming a dietary pattern and supplements with more anti-inflammatory potential after CRC diagnosis may improve overall survival among postmenopausal women.