Association between inflammatory potential of diet and mortality among women in the Swedish Mammography Cohort

Inflammatory potential of diet and mortality in Australian adults

OBJECTIVE

Inflammation is implicated in chronic diseases including cancer and CVD, which are major causes of mortality. Diet can influence inflammation status. We therefore examined whether the inflammatory potential of a person's diet is associated with mortality.

DESIGN

The inflammatory potential of the usual diet was assessed by calculating Dietary Inflammatory Index (DII) scores from repeated FFQ data (collected in 1992, 1994 and 1996), placing each participant's diet on a continuum from anti- to pro-inflammatory. DII scores were analysed as a continuous variable and as categories by creating quartile groups. Death registry data were used to ascertain all-cause mortality and separately mortality from CVD, cancers and other causes between 1992 and 2022. Cox proportional hazard regression analysis was used to calculate adjusted hazard ratios (HR) with 95 % CI, comparing higher and lowest quartile groups, or HR change per one DII unit increase.

SETTING

Nambour, Australia.

PARTICIPANTS

A community-based sample of 1440 adults aged 25-75 years.

RESULTS

During follow-up, 488 participants died, including 188 from CVD, 151 from cancer and 170 from other causes. Participants in the most pro-inflammatory diet group were at increased risk of all-cause mortality (HRQ4 v. Q1 = 1·55; 95 % CI 1·19, 2·03; P < 0·001) and other-cause mortality (HRQ4 v. Q1 = 1·69; 95 % CI 1·12, 2·54; P 0·01). A one-unit increase in DII score was associated with a 36 % increased risk of CVD among those younger than 55 years of age (HR for a one-unit increase in DII score 1·36, 95 % CI 1·04, 1·78). The risk of cancer mortality was also increased for those with a more pro-inflammatory diet in age ≤ 55 years (HR for a one-unit increase in DII score 1·20, 95 % CI 1·02, 1·40) and age 56-65 years (HR for a one-unit increase in DII score 1·11, 95 % CI 1·00, 1·23).

CONCLUSIONS

A pro-inflammatory diet increases the risk of all-cause mortality. Our results support the promotion of anti-inflammatory diets to help promote longevity.

Association of a low-inflammatory diet with survival among adults: The role of cardiometabolic diseases and lifestyle

BACKGROUND & AIMS

Evidence on the association between dietary inflammation and longevity is limited. We aimed to examine the association of a low-inflammatory diet with mortality and longevity, and to explore whether cardiometabolic diseases (CMDs) and lifestyle factors may play a role in this association.

METHODS

Within the UK Biobank, 188,443 participants aged 39-72 years (mean 56.07) were followed for up to 16 years to detect survival status from the death registry. At baseline, dietary intake was assessed with a 24-h dietary record. An inflammatory diet index (IDI) was calculated as weighted sum of 31 food groups (including 14 anti-inflammatory and 17 pro-inflammatory) based on plasma high-sensitivity C-reactive protein levels, and tertiled as low, moderate, and high IDI scores. Baseline lifestyle beyond diet was assessed by summing the number of healthy lifestyle factors (i.e., never smoking, regular physical activity, and normal BMI) and categorized as unfavorable (≤1) and favorable (≥2). Presence of CMDs was defined as having any one of type 2 diabetes, ischemic heart disease, atrial fibrillation, heart failure, and stroke. Data were analyzed using Cox regression, Laplace regression, and generalized structural equation modelling.

RESULTS

During the follow-up (median 9.79 years, interquartile range: 9.68-10.57 years), 9178 (4.9%) participants died. In multi-adjusted Cox regression models, a low-inflammatory diet (i.e. low IDI score) was associated with lower risk of all-cause mortality [hazard ratio (HR) = 0.82, 95% confidence interval (CI): 0.78 to 0.86]. Laplace regression analysis showed that the multi-adjusted 10th percentile difference (10th PD, 95% CI) of death time was delayed by 0.80 (0.55, 1.06; P < 0.001) years for participants with a low IDI score compared to those with a high IDI score. In mediation analysis, 21.48% of the association between IDI and mortality was mediated by CMDs. In joint effect analysis, participants with a low IDI score and favorable lifestyle had a 42% lower risk of death (HR = 0.58, 95% CI: 0.54, 0.62) compared to those with a high IDI score and unfavorable lifestyle. There was a significant additive interaction between low IDI score and favorable lifestyle on decreased mortality.

CONCLUSIONS

A low-inflammatory diet is associated with a lower risk of death and could prolong survival time. CMDs may partially mediate the IDI-mortality association. A favorable lifestyle beyond diet may augment the positive effect of a low-inflammatory diet on longevity.

Association of Pro-Inflammatory Diet with Long-Term Risk of All-Cause and Cardiovascular Disease Mortality: NIPPON DATA80

AIM

A pro-inflammatory diet may increase the risk of cardiovascular disease (CVD) and all-cause mortality. However, this remains inconclusive as there is yet no study using a dietary record method that has been conducted in a large general population. Furthermore, an underestimation of the pro-inflammatory diet may exist due to the unmeasured effect of salt intake. Thus, in this study, we aimed to examine how pro-inflammatory diet is associated with the long-term risk of all-cause and CVD mortality in a representative Japanese population.

METHODS

A national nutrition survey was conducted throughout Japan in 1980. After considering the exclusion criteria, 9284 individuals (56% women aged 30-92 years) were included in this study. In total, 20 dietary parameters derived from 3-day weighed dietary records were used to calculate the dietary inflammatory index (DII). The causes of death were monitored until 2009. The Cox proportional hazards model was used to determine multivariable-adjusted hazard ratios (HRs). Stratified analysis according to salt intake level was also performed.

RESULTS

Compared with the lowest quartile of DII, multivariable-adjusted HRs (95% confidence intervals) in the highest quartile were 1.28 (1.15, 1.41), 1.35 (1.14, 1.60), 1.48 (1.15, 1.92), 1.62 (1.11, 2.38), and 1.34 (1.03, 1.75) for all-cause mortality, CVD mortality, atherosclerotic CVD mortality, coronary heart disease mortality, and stroke mortality, respectively. Stratified analysis revealed stronger associations among individuals with higher salt intake.

CONCLUSIONS

As per our findings, a pro-inflammatory diet was determined to be positively associated with the long-term risk of all-cause and CVD mortality in a representative Japanese population. Thus, considering both salt intake and pro-inflammatory diet is deemed crucial for a comprehensive assessment of CVD risk.

Association between the dietary inflammatory index and all-cause mortality in the U.S. cancer survivors: A prospective cohort study using the National Health and Nutrition Examination Survey database

Background

Cancer remains one of the leading causes of mortality worldwide. Diet can impact inflammation and consequently affect cancer outcomes. The Dietary Inflammatory Index (DII) can serve as a tool to assess the inflammatory potential of cancer survivors' diets and further predict their survival.

Objectives

To investigate the relationship between the DII and the survival of cancer survivors in National Health and Nutrition Examination Survey (NHANES).

Methods

An overall sample of 2359 U.S. cancer survivors from the 2005-2014 cohorts of the NHANES were studied. The DII scores were calculated using 28 dietary components and the mortality status was ascertained until December 31, 2015. Based on the multiple analyses, the relationship between DII and all-cause mortality was examined.

Results

The weighted mean age at baseline was 65.17 ± 14.46 years, 53.16 % were female and 71.30 % were non-Hispanic white. The average DII was 1.51 ± 1.97. After accounting for multiple covariates, positive associations were observed (P < 0.01). Based on Kaplan-Meier survival curves, their significant relationship remains same and the survival probability was decreased among the groups of anti-inflammatory diets (DII < 0) versus pro-inflammatory diets (DII ≥ 0) significantly (Log rank test; P = 0.03). Further analyses were conducted on subgroups and the results are still robust.

Conclusions

An elevated DII was associated with a rising mortality rate among cancer survivors. DII might serve as a potential inflammatory predictor of cancer mortality prognosis, as well as guide nutritional care and even clinical treatment of cancer survivors.

Dietary Inflammatory Potential and the Risk of Serrated and Adenomatous Colorectal Polyps

Studies of dietary inflammation potential and risks of colorectal cancer precursors are limited, particularly for sessile serrated lesions (SSLs). This study examines the association using the energy-adjusted dietary inflammatory index (E-DIITM), a measure of anti- and/or pro-inflammatory diet, in a large US colonoscopy-based case-control study of 3246 controls, 1530 adenoma cases, 472 hyperplastic polyp cases, and 180 SSL cases. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived from logistic regression models. Analyses were stratified by participant characteristics, and urinary prostaglandin E2 metabolite (PGE-M) and high-sensitivity plasma C-reactive protein (hs-CRP) levels, inflammation biomarkers. Highest E-DII™ intake was associated with significantly increased risks of colorectal adenomas (OR 1.36, 95% CI 1.11, 1.67), and hyperplastic polyps (OR 1.43, 95% CI 1.06, 1.98), compared with participants consuming the lowest E-DII™ quartile. A similar, but non-significant, increased risk was also observed for SSLs (OR 1.41, 95% CI 0.82, 2.41). The positive association was stronger in females (pinteraction <0.001), normal weight individuals (ptrend 0.01), and in individuals with lower inflammatory biomarkers (ptrend 0.02 and 0.01 for PGE-M and hs-CRP, respectively). A high E-DII™ is associated with colorectal polyp risk, therefore promoting an anti-inflammatory diet may aid in preventing colorectal polyps.

Associations of dietary and lifestyle inflammation scores with mortality due to CVD, cancer, and all causes among Black and White American men and women

One potential mechanism by which diet and lifestyle may affect chronic disease risk and subsequent mortality is through chronic systemic inflammation. In this study, we investigated whether the inflammatory potentials of diet and lifestyle, separately and combined, were associated with all-cause, all-CVD and all-cancer mortality risk. We analysed data on 18 484 (of whom 4103 died during follow-up) Black and White men and women aged ≥45 years from the prospective REasons for Geographic and Racial Differences in Stroke study. Using baseline (2003-2007) Block 98 FFQ and lifestyle questionnaire data, we constructed the previously validated inflammation biomarker panel-weighted, 19-component dietary inflammation score (DIS) and 4-component lifestyle inflammation score (LIS) to reflect the overall inflammatory potential of diet and lifestyle. From multivariable Cox proportional hazards models, the hazards ratios (HR) and their 95 % CI for the DIS-all-cause mortality and LIS-all-cause mortality risk associations were 1·32 (95 % CI (1·18, 1·47); Pfor trend < 0·01) and 1·25 (95 % CI (1·12, 1·38); Pfor trend < 0·01), respectively, among those in the highest relative to the lowest quintiles. The findings were similar by sex and race and for all-cancer mortality, but weaker for all-CVD mortality. The joint HR for all-cause mortality among those in the highest relative to the lowest quintiles of both the DIS and LIS was 1·91 (95 % CI 1·57, 2·33) (Pfor interaction < 0·01). Diet and lifestyle, via their contributions to systemic inflammation, separately, but perhaps especially jointly, may be associated with higher mortality risk among men and women.

Lower intensity of physical activity strengthens the effect of dietary inflammatory index on the risk of all-cause and cause-specific mortality

To examine the independent and joint associations of dietary inflammation index (DII) and physical activity (PA) with mortality risk. We analyzed data for 20,165 study participants aged ≥ 18 from The Rural Chinese Cohort Study. The Cox proportional hazard model was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) of mortality associated with DII and PA. The dose-response association between DII and mortality risk was intuitively generated by the restricted cubic splines model. During the mean 5.03-year follow-up, a total of 1110 cases of all-cause mortality were identified. Compared with people in quartile 1 of DII, positive associations were found in quartile 4 for all-cause (HR 1.27; 95%CI 1.06-1.52), CVD (HR 1.45; 95%CI 1.09-1.91), and other mortality (HR 1.52; 95%CI 1.10-2.09), while a linear association was demonstrated. Compared with people of quartile 1 of DII and high intensity of PA, those with quartile 4 of DII and low intensity of PA had higher risk of all-cause (HR 1.96; 95%CI 1.50-2.56), CVD (HR 2.68; 95%CI 1.71-4.19), and other mortality (HR 1.83; 95%CI 1.19-2.83). A pro-inflammatory diet was significantly associated with increased risk of mortality and lower PA may strengthen the effect.

Higher modified dietary inflammatory index is associated with increased risk of osteoporosis in US adults: Data from NHANES

Objective

The aim of this study was to study the relationship between modified dietary inflammatory index (MDII) score with osteoporosis (OP) in adult Americans.

Methods

Data were extracted from the United States National Health and Nutrition Examination Survey (NHANES) (2007–2008, 2009–2010, 2013–2014, and 2017–2018). In this cross-sectional study, 5,446 participants were included and analyzed. Potential dietary inflammatory was assessed by MDII score (24-h recall), a composite method computed according to the relationship between nutrients and systemic pro-inflammatory cytokine level, and was further classified into tertiles. Weighted multivariable logistic regression analysis was employed to examine the associations between OP and MDII scores.

Results

In weighted multivariable-adjusted logistic regression models, the highest tertile of MDII score was associated with an increased risk of OP [odds ratio (OR): 1.73, 95% confidence interval (95 CI%): 1.14–2.63]. In participants aged above 59 years, a higher MDII score showed a higher risk of OP (OR: 1.92; 95 CI%: 1.16–3.15). In the sex-stratified models, the results remained significant only among women (OR: 1.80; 95% CI: 1.02–3.17). In the menopausal status stratified model, after adjusting potential confounding variables, the association between the MDII score, either as a categorical (OR: 1.88; 95% CI: 1.07–3.13) or continuous variables (OR: 1.19; 95%CI: 1.02–1.38), and OP risk was significant among postmenopausal women.

Conclusion

Our study indicates that a higher MDII score (pro-inflammatory effect) is significantly associated with an increased risk of OP in US adults, especially among those postmenopausal women more than 60 years. This study further supports that those dietary changes have the potential to prevent OP.

Association of dietary inflammatory potential with risk of overall and cause-specific mortality

Inflammation is a central mechanism in metabolic disorders associated with morbidity and mortality and dietary factors can modulate inflammation. We aimed to prospectively investigate the association between an empirically developed, food-based dietary inflammatory pattern (EDIP) score and the risk of overall and cause-specific mortality, using data from the US National Health and Nutrition Examination Survey from 1999 to 2014. EDIP score was derived by entering thirty-nine predefined commonly consumed food groups into the reduced rank regression models followed by stepwise linear regression, which was most predictive of two plasma inflammation biomarkers including C-reactive protein and leucocyte count among 25 500 US adults. This score was further validated in a testing set of 9466 adults. Deaths from baseline until 31 December 2015 were identified through record linkage to the National Death Index. During a median follow-up of 7·8 years among 40 074 participants, we documented 4904 deaths. Compared with participants in the lowest quintile of EDIP score, those in the highest quintile had a higher risk of overall death (hazard ratio (HR) = 1·19, 95 % CI 1·08, 1·32, P_trend = 0·002), and deaths from cancer (HR = 1·41, 95 % CI 1·14, 1·74, P_trend = 0·017) and CVD (HR = 1·22, 95 % CI 0·98, 1·53, P_trend = 0·211). When stratified by age, the association of EDIP with overall mortality was stronger among individuals under 65 years of age (P_interaction = 0·001). Diets with a higher inflammatory potential were associated with increased risk of overall and cancer-specific mortality. Interventions to reduce the adverse effect of pro-inflammatory diets may potentially promote health and longevity.

Dose-Response Association of Dietary Inflammatory Potential with All-Cause and Cause-Specific Mortality

Although the association of dietary inflammatory potential, evaluated by the dietary inflammatory index (DII), with all-cause and cause-specific mortality has been reported, evidence remains equivocal, with no relevant dose-response meta-analysis having been conducted. To examine the dose-response association of dietary inflammatory potential with risk of all-cause, cancer, and cardiovascular disease (CVD) mortality, PubMed, Embase, and Web of Science were systematically searched up to August 9, 2021. Cohort studies were included if DII was reported as ≥3 levels or per incremental increase, and if the associations of DII with all-cause, cancer, and CVD mortality were assessed. Generalized least squares regression was used to estimate study-specific dose-response associations, and the random effect model was used to pool the RRs and 95% CIs of all-cause, cancer, and CVD mortality per 1-unit increase in DII. Restricted cubic splines were used to intuitively display the dose-response association between dietary inflammatory potential and mortality. Of the 1415 studies retrieved, 15 articles (17 cohort studies involving 397,641 participants) were included in this meta-analysis. With per 1-unit increase in DII, the risks were significantly increased for all-cause mortality (RR: 1.04; 95% CI: 1.03, 1.05, I2 = 51.8%; P-heterogeneity = 0.009), cancer mortality (RR: 1.02; 95% CI: 1.00, 1.04, I2 = 58.6%; P-heterogeneity = 0.013), and CVD mortality (RR: 1.04; 95% CI: 1.02, 1.06, I2 = 85.7%; P-heterogeneity <0.001), respectively. Restricted cubic splines showed significant positive linear associations between DII and the above 3 outcomes. Our study indicated that proinflammatory diets can increase the risk of all-cause, cancer, and CVD mortality in a linear manner.

Dietary Inflammatory Index and Cardiometabolic Risk in Ecuadorian Women

Low-grade systemic inflammation is implicated in metabolic syndrome (MetS) and cardiometabolic diseases. Diet is hypothesized to be an important low-grade inflammation modifier. However, few studies have examined the association of dietary inflammation with MetS and cardiometabolic risk in Latin American populations and their findings are inconsistent. Our cross-sectional study examined the association of dietary inflammatory potential with MetS and cardiometabolic risk components in 276 urban Ecuadorian women. Dietary inflammation was evaluated using an energy-adjusted Dietary Inflammatory Index (E-DII), divided into quartiles (Q). E-DII scores ranged from −4.89 (most anti-inflammatory) to 4.45 (most pro-inflammatory). Participants in the most pro-inflammatory (Q4) compared to the least inflammatory E-DII quartile (Q1) had a 4.4 increased adjusted odds for MetS (95% C.I. = 2.0, 9.63; p < 0.001). Every one-unit increase in E-DII was associated with a 1.4 increase in MetS (95% CI = 1.22, 1.52; p < 0.001). In other adjusted models, the most pro-inflammatory E-DII quartile (Q4) was positively associated with total blood cholesterol and triglycerides (p < 0.001), LDL-c (p = 0.007), diastolic blood pressure (p< 0.002), mean arterial pressure (p < 0.006), waist circumference (p < 0.008), and Framingham risk score (p < 0.001). However, the previously identified associations with pulse wave velocity and BMI were no longer evident in the models. These findings suggest that more pro-inflammatory diets may contribute to poorer cardiometabolic health. Promoting healthier diets with a lower inflammatory potential may help to prevent or slow development of cardiometabolic disorders.

Novel Dietary and Lifestyle Inflammation Scores Directly Associated with All-Cause, All-Cancer, and All-Cardiovascular Disease Mortality Risks Among Women

BACKGROUND

Exogenous exposures collectively may contribute to chronic, low-grade inflammation and increase risks for major chronic diseases and mortality. We previously developed, validated, and reported a novel, FFQ-based and lifestyle questionnaire-based, inflammation biomarker panel-weighted, predominantly whole foods-based 19-component dietary inflammation score (DIS) and 4-component lifestyle inflammation score (LIS; comprising physical activity, alcohol intake, BMI, and current smoking status). Both scores were more strongly associated with circulating biomarkers of inflammation in 3 populations than were previously reported dietary inflammation indices. Associations of the DIS and LIS with mortality risk have not been reported.

OBJECTIVES

To investigate separate and joint associations of the DIS and LIS with all-cause, all-cancer, and cardiovascular disease (CVD) mortality risks in the prospective Iowa Women's Health Study (1986-2012; n = 33,155 women, ages 55-69 years, of whom 17,431 died during follow-up, including 4379 from cancer and 6574 from CVD).

METHODS

We summed each study participant's scores' components, weighted by their published weights, to yield the participant's inflammation score; a higher score was considered more pro-inflammatory. We assessed DIS and LIS mortality associations using multivariable Cox proportional hazards regression.

RESULTS

Among participants in the highest relative to the lowest DIS and LIS quintiles, the adjusted HRs for all-cause mortality were 1.11 (95% CI: 1.05-1.16) and 1.60 (95% CI: 1.53-1.68), respectively; for all-cancer mortality were 1.07 (95% CI: 0.97-1.17) and 1.51 (95% CI: 1.38-1.66), respectively; and for CVD mortality were 1.12 (95% CI: 1.03-1.21) and 1.79 (95% CI: 1.66-1.94), respectively (all Ptrend values < 0.01). Among those in the highest relative to the lowest joint LIS/DIS quintiles, the HRs for all-cause, all-cancer, and all-CVD mortality were 1.88 (95% CI: 1.71-2.08), 1.82 (95% CI: 1.50-2.20), and 1.92 (95% CI: 1.64-2.24), respectively.

CONCLUSIONS

More pro-inflammatory diets and lifestyles, separately but especially jointly, may be associated with higher all-cause, all-cancer, and all-CVD mortality risks among women.

Association Between Inflammatory Diets, Circulating Markers of Inflammation, and Risk of Diverticulitis

BACKGROUND & AIMS

Lifestyle and dietary risk factors for diverticulitis also have been associated with chronic inflammation. We performed a prospective study of associations among the inflammatory potential of diets, circulating markers of inflammation, and the incidence of diverticulitis.

METHODS

We followed 46,418 men, initially free of diverticulitis, from 1986 through 2014 in the Health Professionals Follow-Up Study. We collected data on empiric dietary inflammatory pattern scores, which indicate the inflammatory potential of diets, and determined their association with the risk of incident diverticulitis using Cox proportional hazards regression. We used blood samples provided by 18,225 participants from 1993 through 1995 to conduct a nested case-control study; we used conditional logistic regression to evaluate prediagnostic plasma levels of markers of inflammation, including C-reactive protein (CRP), interleukin 6 (IL6), and tumor necrosis factor-receptor superfamily member 1B, in 310 diverticulitis cases and 310 matched diverticulitis-free individuals (controls).

RESULTS

We documented 1110 cases of incident diverticulitis over 992,589 person-years of follow-up. Compared with participants in the lowest quintile of empiric dietary inflammatory pattern scores, men in the highest quintile had a multivariable-adjusted hazard ratio for diverticulitis of 1.31 (95% CI, 1.07-1.60; Ptrend = .01). The association did not differ significantly by strata of body mass index or vigorous activity (P for interaction > .05 for each). In the nested case-control study, plasma levels of CRP and IL6 were associated with risk of diverticulitis. When we compared extreme quintiles, the multivariable-adjusted relative risk for diverticulitis was 1.85 for CRP (95% CI, 1.04-3.30) and 2.04 for IL6 (95% CI, 1.09-3.84).

CONCLUSIONS

In a large prospective cohort of men, we found that the inflammatory potential of diet and prediagnostic plasma levels of markers of inflammation were associated with incident diverticulitis.

Association between Dietary Inflammatory Index (DII®) and depression and anxiety in the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) Study population

BACKGROUND

Systemic inflammation is emerging as an important factor in the etiology of psychiatric disorders such as depression and anxiety. Therefore, the inflammatory potential of the diet may also be an etiological factor for these conditions, and this may be estimated by calculating the dietary inflammatory index (DII®) score. We aimed to investigate the association between DII score and incidence of depression and anxiety among a representative sample in northeastern Iran.

METHODS

This cross-sectional study undertook in a sub-sample of 7083 adults aged 35 to 65 years recruited as part of Mashhad stroke and heart atherosclerotic disorder (MASHAD) cohort study population, and after excluding subjects with incomplete data. All participants completed the Beck Anxiety Inventory (BAI), the Beck Depression Inventory II (BDI-II), and a validated 65-item food frequency questionnaire (FFQ). Logistic regression was used to evaluate the association between DII score and depression/anxiety score.

RESULTS

Of the study participants, 37.1% (n = 2631) were found to have mild to severe depression, and 50.5% (n = 3580) were affected by mild to severe anxiety. After adjusting for confounding factors, in women, the third (OR: 1.41, 95% CI: 1.06-1.88, p-values< 0.05) and fourth quartiles (OR: 1.37, 95% CI: 1.03-1.83, p-values< 0.05) of DII score were associated with increased risk of a high depression score compared to the first quartile of DII score.

CONCLUSION

There was a significant association between DII score and severe depression among women but not men in this Iranian population. In order to confirm the association between DII food score, depression, and anxiety, further research is required in different populations, and perhaps an intervention study.

Dietary inflammatory index and cardiovascular risk and mortality: A meta-analysis of cohort studies

BACKGROUND

The role of dietary inflammatory index (DII) in cardiovascular disease (CVD) risk and mortality is still controversial. This systematic review and meta-analysis of cohort studies aimed to evaluate the effect of DII, indicating a pro-inflammatory diet, on the incidence and mortality of CVD.

METHODS

A comprehensive literature search of articles published through August 2019 was performed in Medline, EMBASE, and Web of Science. The pooled relative risks (RRs) and 95% confidence intervals (CIs) for highest vs lowest DII in relation to CVD risk or mortality were estimated using a DerSimonian and Laird random effects model. The heterogeneity among studies was tested using Cochran's Q test and I statistic.

RESULTS

A total of 15 cohort studies were finally included in this meta-analysis. The highest DII score was significantly associated with a higher risk of CVD incidence (RR = 1.41, 95% CI 1.12-1.78) or mortality (RR = 1.31, 95% CI 1.19-1.44), compared with the lowest DII score. There was statistically significant heterogeneity among the studies on the association between DII and CVD mortality (P < .001; I = 70.8%). No obvious heterogeneity was observed among the studies on the association between DII and CVD risk (P = .160; I = 37.0%). In the sensitivity analysis, exclusion of any single study did not materially alter the pooled RRs.

CONCLUSION

The present systematic review and meta-analysis indicates that a higher DII score is related to a higher risk of CVD. Further well-designed prospective cohort or trials are warranted to validate our preliminary findings.

A Higher Dietary Inflammatory Index Score is Associated with a Higher Risk of Incidence and Mortality of Cancer: A Comprehensive Systematic Review and Meta-Analysis

Background:

Inflamation is widely known as an adaptive pathophysiological response in a variety of cancers. There is an expanding body of research on the key role of diet in inflammation, a risk factor for all types of cancer. Dietary inflammatory index (DII) was recently develpoed to evalute the inflammatory potential of a diet either as anti-inflammatory or pro-inflammatory. In fact, several studies have shown the association of DII and risk of different cancer types. The aim of this meta-analysis was to investigate the association of DII with risk of incidence and mortality of any cancer types.

Methods:

We searched PubMed-Medline, Scopus, and Web of Science databases for pertient studies util January, 2017. All studies conducted to investigate the association of DII and incidence, mortality, and hospitalization of all cancer types were included. According to degree of heterogeneity, fixed- or random-effect model was employed by STATA software.

Results:

Total 38 studies were eligible for the meta-analysis. The results show that a higher level of DII increases the risk for all cancer types incidence by 32% (OR: 1.32; 95% CI: 1.22-1.42) including digestive tract cancers (OR: 1.55; 95% CI: 1.33-1.78), hormone-dependent cancers (OR: 1.14; 95% CI: 1.04-1.24), respiratory tract cancers (OR: 1.64; 95% CI: 1.11-2.17), and urothelial cancers (OR: 1.36; 95% CI: 1.01-1.73). Moreover, a higher level of DII is in association with a higher risk for mortality caused by all types of cancer by 16% (OR: 1.16; 95% CI: 1.01-1.32). In addition, meta-regression analysis reveals that the design of study can have a significant effect on the association of DII and incidence of all cancer types (slope: 0.54; P= 0.05). The stratified meta-analysis shows that the association of DII and incidence of all cancer types in case-control studies (OR: 1.53; 95% CI: 1.36-1.71) were more prominent than cohort studies (OR: 1.18; 95% CI: 1.07-1.30).

Conclusions:

This study shows that a higher level of DII is associated with a higher risk of incidence and mortality of all cancer types. The findings of the present study suggest that modifying inflammatory properties of dietary patterns can reduce the risk of incidence and mortality of all cancer types.

Association of dietary inflammatory potential with cardiometabolic risk factors and diseases: a systematic review and dose-response meta-analysis of observational studies

CONTEXT

The association of dietary inflammatory index (DII®), as an index of inflammatory quality of diet, with cardiometabolic diseases (CMDs) and risk factors (CMRFs) has been inconsistent in previous studies.

OBJECTIVE

The current systematic review and dose-response meta-analysis was performed to investigate the association of the DII score with CMDs and CMRFs.

DATA SOURCES

All published observational studies (cohort, case-control and cross-sectional) using PubMed/Medline, Scopus, ISI Web of Science, and Google Scholar databases were retrieved from inception through November 2019.

DATA EXTRACTION

Two reviewers independently extracted the data from included studies.

DATA ANALYSIS

Pooled hazard ratio (HR) or odds ratio (OR) were calculated by using a random-effects model.

RESULTS

Ten prospective cohort studies (total n = 291,968) with 31,069 CMDs-specific mortality, six prospective cohort studies (total n = 43,340) with 1311 CMDs-specific morbidity, two case-control studies with 2140 cases and 6246 controls and one cross-sectional study (total n = 15,613) with 1734 CMDs-specific morbidity were identified for CMDs. Meta-analyses of published observational studies demonstrated that the highest DII score category versus the lowest DII score category was associated with 29% increased risk of CMDs mortality (HR = 1.29; 95% confidence interval (CI) 1.18, 1.41). Moreover, there was a significant association between the DII score and risk of CMDs in cohort studies (HR = 1.35; 95% CI 1.13, 1.61) and non-cohort study (HR = 1.36; 95% CI 1.18, 1.57). We found a significant association between the DII score and metabolic syndrome (MetS) (OR: 1.13; 95% CI 1.03, 1.25), hyperglycemia and hypertension. None-linear dose response meta-analysis showed that there was a significant association between the DII score and risk of CMDs mortality (P_nonlinearity < 0.001). Moreover, evidence of none-linear association between the DII score and risk of CMDs was not observed (p-value = 0.1).

CONCLUSIONS

Adherence to pro-inflammatory diet was associated with increased risk of CMDs, mortality and MetS.

The association of dietary patterns and carotid intima-media thickness: A synthesis of current evidence

AIMS

Dietary pattern (DP) analysis has emerged as a holistic method to understand the effects of food intake on health outcomes. Though dietary intake has been associated with cardiovascular disease, the association of DPs and carotid intima-media thickness (CIMT), a robust early marker of cardiovascular disease progression has not been comprehensively investigated. This study systematically explores the association of a posteriori and a priori DPs and CIMT.

DATA SYNTHESIS

Through a systematic search of MEDLINE, CINAHL, and Web of Science, twenty studies that derived DPs using a posteriori or a priori methods with CIMT as an outcome were included. Four cross-sectional studies and 1 cohort paper reported a statistically significant association between increased consumption of 'unhealthy' foods (i.e processed meat, soda drinks and refined grain) and increased CIMT. While four cross-sectional studies reported a statistically significant association of DPs characterized by increased consumption of 'healthy' foods (i.e fruit and vegetables, fish) and decreased CIMT. DPs derived from each study varied depending on derivation method, study design and use of dietary data collection method.

CONCLUSION

Findings from this review are generally supportive of a trend between DPs with higher consumption of 'healthy' foods and lower consumption of 'unhealthy' foods and decreased CIMT; however, the association was largely not statistically significant. Evidence was overwhelmingly heterogeneous due to differences seen in DPs based on location and culture, sample characteristics and adjustment for confounders. Long-term prospective observational and interventional studies with standardized sample selection and dietary data collection are needed to significantly establish the role of DPs on CIMT.

Association between dietary inflammatory index and risk of cardiovascular disease in the Mashhad stroke and heart atherosclerotic disorder study population

The dietary inflammatory index (DII) is a novel way of describing diet that has been studied in relation to various health conditions, including cardiovascular disease (CVD) in several populations. We aimed to investigate the association between DII and CVD events among a representative population sample in northeastern Iran. This prospective cohort study was a subsample of 4,672 adults aged 35-65 years, and recruited as part of Mashhad stroke and heart atherosclerotic disorder cohort study population. The DII was computed at baseline according to a 65-item validated food frequency questionnaire. Cox regression was used to determine the association of DII with incident CVD. One hundred twenty-four participants developed CVD (including 24 cases of myocardial infarction [MI], 34 cases of stable angina [SA], and 66 cases of unstable angina [UA]). After adjusting for potential confounding factors, a hazard ratios of 1.06 (95% confidence interval: 0.70-1.60), 1.36 (95% confidence interval: 0.52-3.52), 1.33 (95% confidence interval: 0.60-2.94), and 0.86 (95% confidence interval: 0.48-1.53) were found for total CVD, MI, SA, and UA events, respectively, among the participants with proinflammatory diet (DII ≥ 0) versus those with anti-inflammatory diet (DII < 0). There was no statistically significant association between the DII and total CVD, MI, SA, or UA in this population of middle-aged Iranian men and women.

Secular trends in Dietary Inflammatory Index among adults in the United States, 1999-2014

OBJECTIVE

The objective of this study was to evaluate secular trends in Dietary Inflammatory Index (DII) scores in the United States between 1999 and 2014.

METHODS

Data from adults over 19 years from the 1999 to 2014 National Health and Nutrition Examination Survey (N = 39,191) were used. DII scores, at each 2-year cycle, were evaluated from a 24-h recall, including 26 food parameters for DII calculation. Analyses were conducted in 2018.

RESULTS

For the entire sample, there was a quadratic trend (Ptrend < 0.001), with the DII scores peaking in 2003-2004, and then decreasing during the cycles from 2005 to 2014. Similar quadratic trends (Ptrend < 0.001) were observed by age, gender, race-ethnicity, and education.

CONCLUSION

Males, non-Hispanic Blacks, younger adults, and those with less education adults had the highest DII scores (i.e., indicating the greatest inflammatory potential). The overall DII scores of the US population showed a quadratic trend from 1999 to 2014. Continued monitoring of DII changes is needed to better understand changes in the inflammatory potential of diet of American adults, and how they relate to changes in the risk of chronic disease.

Dietary Inflammatory Index Is Associated with Risk of All-Cause and Cardiovascular Disease Mortality but Not with Cancer Mortality in Middle-Aged and Older Japanese Adults

BACKGROUND

The Dietary Inflammatory Index (DII) is a comprehensive, literature-derived index for assessing the effect of dietary constituents on inflammatory biomarkers. Several studies have shown an association between DII score and mortality, but there are limited prospective studies in Asian populations.

OBJECTIVES

The aim of this study was to investigate the association between DII score and risk of all-cause, total cardiovascular disease (CVD), stroke, coronary heart disease (CHD), total cancer, digestive cancer, and noncancer/non-CVD mortality in the Japanese population.

METHODS

A total of 58,782 Japanese participants aged 40-79 y who were enrolled in the Japan Collaborative Cohort Study during 1988-1990 were included in the analysis. DII scores were calculated based on a food-frequency questionnaire. HRs and 95% CIs for mortality according to DII quintiles were estimated using Cox proportional hazards models.

RESULTS

During the median follow-up period of 19.3 y, a total of 11,693 participants died. The multivariable HR for all-cause mortality for the highest compared with the lowest DII quintiles was 1.13 (95% CI: 1.05, 1.21). For CVD mortality, the highest multivariable HRs were 1.30 (95% CI: 1.13, 1.49), 1.29 (95% CI: 1.05, 1.59), and 1.30 (95% CI: 0.96, 1.76) for total CVD, stroke, and CHD, respectively. No significant associations were observed between DII and risk of total cancer, digestive cancer, and noncancer/non-CVD mortality.

CONCLUSION

Our findings suggest that a higher DII was associated with an increased risk of all-cause and CVD mortality among Japanese adults.

Influence of anti-inflammatory diet and smoking on mortality and survival in men and women: two prospective cohort studies

BACKGROUND

The associations between an anti-inflammatory diet and both all-cause and cause-specific mortality have been studied previously; however, the influence of an anti-inflammatory diet on survival time has not been investigated. Moreover, the potential modification of these associations by smoking status remains unclear.

OBJECTIVE

The aims of this study were to examine the associations between an anti-inflammatory diet index (AIDI) and all-cause and cause-specific mortality, to determine the association between the AIDI and differences in survival time and to assess effect modification by smoking status.

METHODS

The study population included 68 273 Swedish men and women (aged 45-83 years) at baseline. The anti-inflammatory potential of the diet was estimated using the validated AIDI, which includes 11 potential anti-inflammatory and five potential pro-inflammatory foods. Cox proportional hazards and Laplace regression were used to estimate hazard ratios and differences in survival time.

RESULTS

During 16 years of follow-up (1 057 959 person-years), 16 088 deaths [5980 due to cardiovascular disease (CVD) and 5252 due to cancer] were recorded. Participants in the highest versus lowest quartile of the AIDI had lower risks of all-cause (18% reduction, 95% CI: 14-22%), CVD (20%, 95% CI: 14-26%) and cancer (13%, 95% CI: 5-20%) mortality. The strongest inverse associations between the highest and lowest quartiles of AIDI and risk of mortality were observed in current smokers: 31%, 36% and 22% lower risks of all-cause, CVD and cancer mortality, respectively. The difference in survival time between current smokers in the lowest AIDI quartile and never smokers in the highest quartile was 4.6 years.

CONCLUSION

Adherence to a diet with high anti-inflammatory potential may reduce all-cause, CVD and cancer mortality and prolong survival time especially amongst smokers.

Diet-related inflammation and risk of prostate cancer in the California Men's Health Study

PURPOSE

The purpose of the study was to examine the relationship between proinflammatory diet and prostate cancer risk.

METHODS

Energy-adjusted Dietary Inflammatory Index (E-DII) scores were computed among 40,161 participants in the California Men's Health Study. Over 9.7 ± 3.8 years of follow-up, 2707 incident prostate cancer cases were diagnosed and categorized as low-, intermediate-, or high-risk, based on disease grade and stage. Accelerated failure-time models assessed time to diagnosis of prostate cancer. Cox proportional hazard models estimated hazard ratios (HR) and 95% confidence intervals (95% CI). Nonlinear effects of E-DII were modeled as third-order polynomials.

RESULTS

Time to prostate cancer diagnosis did not differ by E-DII quartile. The HR for high-risk prostate cancer increased in the third E-DII quartile (HRQ3 vs. Q1 = 1.36; 95% CI: 1.04-1.76), but not in the fourth (HRQ4 vs. Q1 = 0.99; 95% CI: 0.74-1.32, Ptrend = .74), suggesting a nonlinear dose-response. HR curves for prostate cancer increased exponentially above an E-DII threshold of ≈+3.0. HR curves for high-risk prostate cancer had a much steeper incline above an E-DII threshold of ≈+2.5. Curves were higher among Blacks and Whites relative to other races and among overweight or obese men. No relationship was observed between E-DII scores and intermediate- or low-risk disease.

CONCLUSIONS

Relationships between proinflammatory diet and prostate cancer risk may be nonlinear, with an increased risk above an E-DII threshold of ≈+2.5.

The Dietary Inflammatory Index and All-Cause, Cardiovascular Disease, and Cancer Mortality in the Multiethnic Cohort Study

Diet quality based on inflammatory potential, assessed by the Dietary Inflammatory Index (DII®), has been related to mortality, but studies from racially/ethnically diverse populations are scarce. Using data from the Multiethnic Cohort Study in Hawaii and California, we investigated the association of the DII with all-cause, cardiovascular disease (CVD) and cancer mortality, both overall and by race/ethnicity. The analysis included 150,405 African Americans, Native Hawaiians, Japanese Americans, Latinos, and Whites aged 45⁻75 years, with 47,436 deaths during an average follow-up of 18.2 ± 4.9 years. In multivariable-adjusted Cox models, the hazard ratios (95% confidence intervals) for the highest vs. lowest quintile of the DII in men and women were 1.15 (1.09⁻1.21) and 1.22 (1.14⁻1.28) for all-cause, 1.13 (1.03⁻1.23) and 1.29 (1.17⁻1.42) for CVD, and 1.10 (1.00⁻1.21) and 1.13 (1.02⁻1.26) for cancer mortality. In men, an increased risk of all-cause mortality with higher DII scores was found in all racial/ethnic groups except for Native Hawaiians (P for heterogeneity < 0.001). Similarly, in women, an increased risk of CVD mortality was found in the four racial/ethnic groups, but not in Native Hawaiians. These findings support the association of a pro-inflammatory diet with a higher risk of mortality and suggest the association may vary by race/ethnicity.

The association between the inflammatory potential of diet and risk of developing, and survival following, a diagnosis of ovarian cancer

PURPOSE

Inflammation has been implicated in ovarian carcinogenesis. This study evaluated two dietary indices: the Dietary Inflammatory Index (DII®) and the Empirical Dietary Inflammatory Pattern (EDIP), in relation to risk of developing, and survival following, a diagnosis of ovarian cancer.

METHODS

Data came from the Australian Ovarian Cancer Study (1375 cases, 1415 population controls). DII and EDIP scores were computed from dietary information obtained using a semiquantitative food-frequency questionnaire. Logistic regression was used to assess the association between DII and EDIP scores and risk of ovarian cancer and proportional hazards models were used for survival analysis.

RESULTS

A high DII score, reflecting a more pro-inflammatory diet, was associated with a modest increased risk of ovarian cancer [odds ratio (OR) DII score_{Q4 vs.Q1} = 1.31, 95% CI 1.06-1.63, p_trend = 0.014]. Likewise a high EDIP score was associated with an increase in risk of ovarian cancer [OR EDIP score_{Q4 vs.Q1} = 1.39, 95% confidence interval (CI) 1.12-1.73, p_trend = 0.002]. We found no association between DII or EDIP score and overall or ovarian cancer-specific survival.

CONCLUSION

In conclusion, our results suggest that a pro-inflammatory diet modestly increases the risk of developing ovarian cancer.

Dietary Inflammatory Index and Cardiovascular Risk and Mortality-A Meta-Analysis

Diet and chronic inflammation have been suggested to be risk factors in the development of cardiovascular disease (CVD) and related mortality. The possible link between the inflammatory potential of diet measured through the Dietary Inflammatory Index (DII^®) and CVD has been investigated in several populations across the world. The aim of this study was to conduct a meta-analysis on studies exploring this association. Data from 14 studies were eligible, of which two were case-control, eleven were cohort, and one was cross-sectional. Results from the random-effects meta-analysis showed a positive association between increasing DII, indicating a pro-inflammatory diet, and CVD. Individuals in the highest versus the lowest (reference) DII category showed a 36% increased risk of CVD incidence and mortality, with moderate evidence of heterogeneity (relative risk (RR) = 1.36, 95% confidence interval (CI): 1.19, 1.57; heterogeneity index I² = 69%, p < 0.001). When analyzed as a continuous variable, results showed an increased risk of CVD risk and mortality of 8% for each one-point increase in the DII score. Results remained unchanged when analyses were restricted to the prospective studies. Results of our meta-analysis support the importance of adopting a healthier anti-inflammatory diet for preventing CVD incidence and related mortality. In conclusion, a pro-inflammatory diet is associated with increased risk of CVD and CVD mortality. These results further substantiate the utility of DII as tool to characterize the inflammatory potential of diet and to predict CVD incidence and mortality.

A Pro-Inflammatory Diet Is Associated With an Increased Odds of Depression Symptoms Among Iranian Female Adolescents: A Cross-Sectional Study

Background: The relation between dietary inflammation and risk of depression has not been widely explored. We examined the association between the inflammatory effect of the diet and the odds of depression among Iranian female adolescents. Methods: Using a stratified cluster sampling technique, 300 female adolescents aged 15-18 years were recruited from schools in Tehran between years 2014-2015. Depression was assessed using the Depression, Anxiety and Stress Scale (DASS)- a 21-point scale. The dietary inflammatory index (DII®) was used to evaluate the inflammatory potential of the diet. Dietary intake was assessed using a validated food frequency questionnaire. In addition to descriptive statistics, multivariable linear and logistic regression were used to calculate confounder-adjusted beta estimates and odds ratios. Results: In total, 88 females (30%) had at least a moderate level of depressive symptoms (DASS > 6). Females with the most pro-inflammatory diet had higher DASS depression score (β = 1.67; 95% CI = 0.03, 3.31) and were at 3.96 (95% CI = 1.12, 13.97) times higher odds of having at least moderate depressive symptoms, compared to females with the least anti-inflammatory diets. Conclusion: These data suggest that Iranian adolescent females eating a pro-inflammatory diet, as indicated by higher DII scores, had greater odds of having at least moderate depressive symptoms.

Alternative Healthy Eating Index 2010, Dietary Inflammatory Index and risk of mortality: results from the Whitehall II cohort study and meta-analysis of previous Dietary Inflammatory Index and mortality studies

We aimed to examine the association between the Alternative Healthy Eating Index updated in 2010 (AHEI-2010), the Dietary Inflammatory Index (DIITM) and risk of mortality in the Whitehall II study. We also conducted a meta-analysis on the DII-based results from previous studies to summarise the overall evidence. Data on dietary behaviour assessed by self-administered repeated FFQ and on mortality status were available for 7627 participants from the Whitehall II cohort. Cox proportional hazards regression models were performed to assess the association between cumulative average of AHEI-2010 and DII scores and mortality risk. During 22 years of follow-up, 1001 participants died (450 from cancer, 264 from CVD). Both AHEI-2010 (mean=48·7 (sd 10·0)) and DII (mean=0·37 (sd 1·41)) were associated with all-cause mortality. The fully adjusted hazard ratio (HR) per sd, were 0·82; 95 % CI 0·76, 0·88 for AHEI-2010 and 1·18; 95 % CI 1·08, 1·29 for DII. Significant associations were also observed with cardiovascular and cancer mortality risk. For DII, a meta-analysis (using fixed effects) from this and four previous studies showed a positive association of DII score with all-cause (HR=1·04; 95 % CI 1·03, 1·05, 28 891deaths), cardiovascular (HR=1·05; 95 % CI 1·03, 1·07, 10 424 deaths) and cancer mortality (HR=1·05; 95 % CI 1·03, 1·07, n 8269).The present study confirms the validity to assess overall diet through AHEI-2010 and DII in the Whitehall II cohort and highlights the importance of considering diet indices related to inflammation when evaluating all-cause, cardiovascular and cancer mortality risk.

Inflammatory potential of diet and risk of cardiovascular disease or mortality: A meta-analysis

Inconsistent findings have reported on the inflammatory potential of diet and cardiovascular disease (CVD) and mortality risk. The aim of this meta-analysis was to investigate the association between the inflammatory potential of diet as estimated by the dietary inflammatory index (DII) score and CVD or mortality risk in the general population. A comprehensive literature search was conducted in PubMed and Embase databases through February 2017. All prospective observational studies assessing the association of inflammatory potential of diet as estimated by the DII score with CVD and all-cause, cancer-related, cardiovascular mortality risk were included. Nine prospective studies enrolling 134,067 subjects were identified. Meta-analyses showed that individuals with the highest category of DII (maximal pro-inflammatory) was associated with increased risk of all-cause mortality (hazard risk [HR] 1.22; 95% confidence interval [CI] 1.06-1.41), cardiovascular mortality (RR 1.24; 95% CI 1.01-1.51), cancer-related mortality (RR 1.28; 95% CI 1.04-1.58), and CVD (RR 1.32; 95% CI 1.09-1.60) than the lowest DII score. More pro-inflammatory diets, as estimated by the higher DII score are independently associated with an increased risk of all-cause, cardiovascular, cancer-related mortality, and CVD in the general population, highlighting low inflammatory potential diet may reduce mortality and CVD risk.

Dietary inflammatory index in relation to sub-clinical atherosclerosis and atherosclerotic vascular disease mortality in older women

Arterial wall thickening, stimulated by low-grade systemic inflammation, underlies many cardiovascular events. As diet is a significant moderator of systemic inflammation, the dietary inflammatory index (DIITM) has recently been devised to assess the overall inflammatory potential of an individual's diet. The primary objective of this study was to assess the association of the DII with common carotid artery-intima-media thickness (CCA-IMT) and carotid plaques. To substantiate the clinical importance of these findings we assessed the relationship of DII score with atherosclerotic vascular disease (ASVD)-related mortality, ischaemic cerebrovascular disease (CVA)-related mortality and ischaemic heart disease (IHD)-related mortality more. The study was conducted in Western Australian women aged over 70 years (n 1304). Dietary data derived from a validated FFQ (completed at baseline) were used to calculate a DII score for each individual. In multivariable-adjusted models, DII scores were associated with sub-clinical atherosclerosis: a 1 sd (2·13 units) higher DII score was associated with a 0·013-mm higher mean CCA-IMT (P=0·016) and a 0·016-mm higher maximum CCA-IMT (P=0·008), measured at 36 months. No relationship was seen between DII score and carotid plaque severity. There were 269 deaths during follow-up. High DII scores were positively associated with ASVD-related death (per sd, hazard ratio (HR): 1·36; 95 % CI 1·15, 1·60), CVA-related death (per sd, HR: 1·30; 95 % CI 1·00, 1·69) and IHD-related death (per sd, HR: 1·40; 95 % CI 1·13, 1·75). These results support the hypothesis that a pro-inflammatory diet increases systemic inflammation leading to development and progression of atherosclerosis and eventual ASVD-related death.

Biomarker-calibrated nutrient intake and healthy diet index associations with mortality risks among older and frail women from the Women's Health Initiative

Background: Although studies to date have confirmed the association between nutrition and frailty, the impact of dietary intake and dietary patterns on survivorship in those with frailty is yet to be examined in a well-powered cohort with validated frailty status. Moreover, previous studies were limited by measurement error from dietary self-reports.Objective: We derived biomarker-calibrated dietary energy and protein intakes to address dietary self-report error. Using these data, we then evaluated the association of mortality in older women with frailty and dietary intake and healthy diet indexes, such as the alternate Mediterranean Diet (aMED), the Dietary Approaches to Stop Hypertension (DASH) score, and the Dietary Inflammatory Index (DII).Design: The analytic sample included 10,034 women aged 65-84 y with frailty and complete dietary data from the Women's Health Initiative Observational Study. Frailty was assessed with modified Fried's criteria. Dietary data were collected by food-frequency questionnaire.Results: Over a mean follow-up period of 12.4 y, 3259 (31%) deaths occurred. The HRs showed progressively decreased rates of mortality in women with higher calibrated dietary energy intakes (P-trend = 0.003), higher calibrated dietary protein intakes (P-trend = 0.03), higher aMED scores (P-trend = 0.006), and higher DASH scores (P-trend = 0.02). Although the adjusted point estimates of HRs (95% CIs) for frail women scoring in the second, third, and fourth quartiles on DII measures were 1.15 (1.03, 1.27), 1.28 (1.15, 1.42), and 1.24 (1.12, 1.38), respectively, compared with women in the first quartile, no overall effect was observed across quartiles (P-trend = 0.35). Subgroup analyses by chronic morbidity or smoking status or by excluding women with early death did not substantially change these findings.Conclusions: The current study highlights the importance of nutrition in older, frail women. Diet quality and quantity should be considered in managing persons with frailty.

Inflammatory potential of the diet and mortality in the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Spain)

SCOPE

Low-grade chronic inflammation is associated with several chronic conditions, and diet is known to play a role in chronic inflammation. We aimed to evaluate the association between the inflammatory potential of the diet and mortality in the Spanish population from the European Prospective Investigation into Cancer and Nutrition (EPIC-Spain).

METHODS AND RESULTS

The study included 41 199 participants (62% female) aged 29-69 years from five Spanish regions. During 18 years of follow-up 3316 deaths were identified. The dietary inflammatory potential was assessed by means of an inflammatory score of the diet (ISD), calculated using 30 dietetic components and their corresponding inflammatory scores (weights). The association between the ISD and mortality was analyzed by multivariate Cox regression models. There was a significant association between ISD and mortality: subjects classified in the fifth quintile of the ISD (more proinflammatory diets) had a hazard ratio of 1.42 (95%-confidence interval 1.25-1.60) as compared with those in the first quintile; the corresponding figures were 1.89 (1.48-2.40) for cardiovascular diseases mortality and 1.44 (1.22-1.69) for death by cancer.

CONCLUSION

Consuming more proinflammatory diets, expressed by means of the ISD, is associated with higher mortality; this effect seems to be stronger for deaths by cardiovascular diseases.

Association between Dietary Inflammatory Index and Gastric Cancer Risk in an Italian Case-Control Study

BACKGROUND

In this study, we explored the association between the dietary inflammatory index (DII) and gastric cancer risk in an Italian case-control study.

MATERIALS AND METHODS

Cases were 230 patients with incident, histologically confirmed cases of gastric cancer from the Greater Milan area, Northern Italy. Controls were 547 frequency-matched subjects admitted to the same network of hospitals as cases for a wide spectrum of acute, non-neoplastic conditions. The DII was computed using a reproducible and valid 78-item food frequency questionnaire. Odds ratios (ORs) were estimated through logistic regression models conditioned on age and sex and adjusted for recognized confounding factors, including total energy intake.

RESULTS

Subjects with the most pro-inflammatory diet had a higher risk of gastric cancer compared to subjects with the most anti-inflammatory diet (ORQuartile4vs1 = 2.35, 95% confidence interval, 1.32, 4.20; P-trend = 0.004).

CONCLUSION

These results indicate that a pro-inflammatory diet, as indicated by higher DII score, was associated with increased risk of gastric cancer.

Association between inflammatory potential of diet and risk of depression in middle-aged women: the Australian Longitudinal Study on Women's Health

Dietary factors and inflammation markers have been shown to play a role in the development of depression. However, there are very few studies that have explored the association between inflammatory potential of diet and risk of depression. In this study, we examined the association between the dietary inflammatory index (DII), which was developed specifically to measure the inflammatory potential of diet, and risk of depression in the middle-aged cohort of the Australian Longitudinal Study on Women's Health. A total of 6438 women with a mean age of 52·0 (sd 1·4) years at baseline were followed-up at five surveys over 12 years (2001-2013). Depression was defined as a score of ≥10 on the Center for Epidemiologic Studies Depression-10 scale. The DII score, a literature-derived, population-based dietary index that has been validated against several inflammatory markers, was computed on the basis of dietary intake assessed using a validated FFQ. Generalised estimating equations were used to estimate relative risk (RR) of depression according to DII score. Models were adjusted for energy intake, highest education completed, marital status, menopause status and symptoms, personal illness or injury, smoking status, physical activity, BMI and depression diagnosis or treatment. In total, 1156 women (18 %) had scores≥10 on the CESD scale over the course of 9 years. Women with the most anti-inflammatory diet had an approximately 20 % lower risk of developing depression compared with women with the most pro-inflammatory diet (RRDII quartile 1 v. 4: 0·81; 95 % CI 0·69, 0·96; P trend=0·03). These results suggest that an anti-inflammatory diet is associated with lower risk of depression in middle-aged Australian women.

The Role of Dietary Inflammatory Index in Cardiovascular Disease, Metabolic Syndrome and Mortality

Inflammation is an underlying pathophysiological process in chronic diseases, such as obesity, type 2 diabetes mellitus and cardiovascular disease. In fact, a number of systematic reviews have shown the association between inflammatory biomarkers, such as CRP, IL-1β, IL-6, TNF-α, IL-4, or IL-10, and cardio-metabolic diseases. Diet is one of the main lifestyle-related factors which modulates the inflammatory process. Different individual foods and dietary patterns can have a beneficial health effect associated with their anti-inflammatory properties. The dietary inflammatory index (DII) was recently developed to estimate the inflammatory potential of overall diet. The aim of this review is to examine the findings of recent papers that have investigated the association between the DII, cardio-metabolic risk factors and cardiovascular disease. The relevance of the DII score in the association between inflammation and cardio-metabolic diseases is critically appraised, as well as its role in the context of healthy dietary patterns. We conclude that the DII score seems to be a useful tool to appraise the inflammatory capacity of the diet and to better understand the relationships between diet, inflammation, and cardio-metabolic diseases.

Dietary inflammatory index and prostate cancer survival

Systemic inflammatory status has been reported to impact survival of prostate cancer (PCa) patients; however, evidence is lacking on whether the inflammatory potential of diet can influence prognosis of PCa patients. To investigate the association between a dietary inflammatory index (DII) and PCa survival, we conducted a retrospective cohort study including 726 men with PCa originally enrolled, between 1995 and 2002, in an Italian case-control study. Information on diet and Gleason score was collected at PCa diagnosis. DII was derived from a food frequency questionnaire using a validated algorithm. Adjusted hazard ratios (HRs) of death with 95% confidence intervals (CIs) were estimated using a Fine-Gray model. DII scores were not significantly associated with all-cause mortality of PCa patients (HR highest vs. lowest DII tertile = 1.25; 95% CI: 0.86-1.83). However, considerable heterogeneity emerged according to Gleason score (p < 0.01): no associations emerged among men with Gleason score 2-6 PCa; whereas, among patients with Gleason score 7-10 PCa, DII was directly associated with both all-cause and PCa-specific mortality (HR highest vs. lowest DII tertile: 2.78; 95% CI: 1.41-5.48; and 4.01; 95% CI: 1.25-12.86; respectively). Among patients with Gleason score 7-10 PCa, ten-year all-cause survival probabilities were 58% (95% CI: 47-67%) for highest and 78% (95% CI: 67-86%) for lowest DII tertile. Study findings support the hypothesis that diet, through its inflammatory potential, may influence the prognosis of patients with more aggressive PCa. Dietary interventions aimed at decreasing inflammation may be considered to improve survival of men with PCa.

Prospective association between the Dietary Inflammatory Index and mortality: modulation by antioxidant supplementation in the SU.VI.MAX randomized controlled trial

BACKGROUND

Chronic inflammation is a central mechanism involved in cardiovascular diseases, cancer, diabetes, and chronic respiratory diseases, 4 leading causes of mortality. Diet is a major source of pro- and anti-inflammatory bioactive compounds. The Dietary Inflammatory Index (DII) was designed to estimate the overall inflammatory potential of the diet.

OBJECTIVE

Our aim was to study the prospective association between the DII and mortality, as well as assess whether antioxidant supplementation could modulate this association.

DESIGN

The Supplémentation en Vitamines et Minéraux Antioxydants study was a randomized, double-blind, placebo-controlled trial in which participants received low-dose antioxidants or a placebo from 1994 to 2002. In this observational prospective analysis, 8089 participants (mean ± SD age at baseline: 49.0 ± 6.3 y) were followed between 1994 and 2007 (median: 12.4 y). The DII was calculated from repeated 24-h dietary records; higher scores correspond to more proinflammatory diets. A total of 207 deaths occurred during follow-up, including 123 due to cancer and 41 due to cardiovascular events. Multivariate Cox proportional hazards models were computed.

RESULTS

Sex-specific tertiles of the DII were positively associated with cardiovascular + cancer mortality (HR for tertile 3 compared with tertile 1 = 1.53; 95% CI: 1.01, 2.32; P-trend = 0.05) and specific cancer mortality (HR for tertile 3 compared with tertile 1 = 1.83; 95% CI: 1.12, 2.99; P-trend = 0.02). The corresponding P value was 0.07 for all-cause mortality. The DII was statistically significantly associated with increased all-cause mortality in the placebo group (HR for tertile 3 compared with tertile 1 = 2.10; 95% CI: 1.15, 3.84; P-trend = 0.02) but not in the antioxidant-supplemented group (P-trend = 0.8; P-interaction = 0.098).

CONCLUSION

These results suggest that a proinflammatory diet is associated with increased all-cause and cancer mortality and antioxidants may counteract some of the proinflammatory effects of the diet. This trial was registered at clinicaltrials.gov as NCT00272428.

Inflammatory potential of diet and all-cause, cardiovascular, and cancer mortality in National Health and Nutrition Examination Survey III Study

BACKGROUND

Various dietary components have been studied in relation to overall mortality; however, little is known about the relationship between the inflammatory potential of overall diet and mortality.

MATERIALS AND METHODS

We examined the association between the dietary inflammatory index (DII) and mortality in the National Health and Nutrition Examination Survey III follow-up study. The DII was computed from baseline dietary intake assessed using 24-h dietary recalls (1988-1994). Mortality was determined from the National Death Index records through 2006. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95 % confidence interval (95 % CI). During the follow-up, 2795 deaths were identified, including 1233 due to cardiovascular disease (CVD), and 615 due to cancer, 158 of which were due to digestive-tract cancers.

RESULTS

Multivariate Cox proportional hazards regression analyses, adjusting for age, race, diabetes status, hypertension, physical activity, body mass index, poverty index, and smoking, revealed positive associations between higher DII scores and mortality. Comparing subjects in DII tertile 3 versus tertile 1, significant associations were noted for all-cause mortality (HR_Tertile3vs1 1.34; 95 % CI 1.19-1.51, P _trend < 0.0001), CVD mortality (HR_Tertile3vs1 1.46; 95 % CI 1.18-1.81, P _trend = 0.0006), cancer mortality (HR_Tertile3vs1 1.46; 95 % CI 1.10-1.96, P _trend = 0.01), and digestive-tract cancer mortality (HR_Tertile3vs1 2.10; 95 % CI 1.15-3.84, P _trend = 0.03).

CONCLUSION

These results indicate that a pro-inflammatory diet, as indicated by higher DII scores, was associated with higher risk of all-cause, CVD, and cancer mortality.