Association between dietary inflammatory index and metabolic syndrome: Analysis of the NHANES 2005-2016

The relationship between dietary inflammatory index (DII) and early renal injury in population with/without hypertension: analysis of the National health and nutrition examination survey 2001-2002

BACKGROUND

Inflammation plays a crucial role in occurrence of kidney injury, and specific dietary patterns can influence systemic inflammation levels. However, the relationship between dietary inflammatory potential and early-stage kidney damage remains unclear.

METHOD

2,108 participants was recruited from 2001-2002 National Health and Nutrition Examination Survey (NHANES). Dietary Inflammatory Index (DII) is utilized to assess dietary inflammatory potential, calculated through a 24-h dietary recall questionnaire. Early renal injury was evaluated using urinary albumin to creatinine (UACR), cystatin C (CysC), β-2 microglobulin (β2M), and estimated glomerular filtration rate (eGFR) based on serum creatinine (eGFRs), cystatin C (eGFRc), and both Scr and CysC (eGFRs&c). Participant characteristics were analyzed, and association between DII, hypertension, and early renal injury markers was explored using multiple linear and logistic regression models.

RESULTS

The average age of participants was 53.9 years. DII exhibited a positive correlation with UACR (β = -0.048[0.017,0.078]), β2M (β = 0.019[0.010,0.027]), CysC (β = 0.012 [0.004,0.021]). Conversely, a negative correlation was observed between DII and eGFRc (β = -1.126[-1.554, -0.699]), eGFRs&c (β=-1.101[-1.653, -0.549]). A significant association was observed between hypertension and abnormality of early kidney damage markers. Subgroup analysis reveals that the positive correlation between DII and the occurrence of abnormal markers of early kidney damage is only observed in individuals with hypertension. Furthermore, an interaction between DII and hypertension was detected in eGFRs&c (OR:1.250[1.042, 1.499], p for interaction = 0.03).

CONCLUSION

Higher levels of DII may be associated with occurrence of early kidney damage. For individuals with hypertension, avoiding excessive consumption of pro-inflammatory foods may reduce the risk of renal injury.

Association between dietary inflammatory index and energy-adjusted dietary inflammatory index and constipation in US adults

BACKGROUND

Diet and inflammation are associated with constipation. Dietary inflammation index (DII) and energy-dietary inflammation index (E-DII) have not been evaluated together with constipation. Therefore, this study was conducted to further observe the relationship between DII and E-DII and constipation in American adults.

METHODS

Data were extracted from the National Health and Nutrition Examination Survey (NHANES) for 12,400 adults aged 20 years and older between 2005 and 2010. DII and E-DII were obtained by employing data from the two 24-h dietary recall of the participants. Constipation was defined and categorized using the Bristol Stool Form Scale.

RESULTS

In the logistic regression model, the relationship between DII and E-DII and constipation remained positive after adjusting for confounding factors (odds ratio [OR] = 1.13; 95% confidence interval [CI]: 1.07-1.20 in DII logistic regression model III; odds ratio [OR] = 1.09; 95% confidence interval [CI]: 1.03-1.17 in E-DII logistic regression model III). Constipation was more common in quartile 4 (DII: 2.87-5.09; E-DII: 1.78-8.95) than in quartile 1 (DII: -5.11-0.25; E-DII: -2.60-0.11) (OR = 1.79, 95% CI: 1.30-2.47 in DII and OR = 1.75, 95% CI: 1.25-2.46 in E-DII for all participants; OR = 2.04, 95% CI: 1.39-3.00 in DII OR = 2.20, 95% CI: 1.39-3.47 in E-DII for males; OR = 1.86, 95% CI: 1.08-3.22 and OR = 1.80, 95% CI: 1.06-3.06 for females). These results were confirmed using multiple imputations.

CONCLUSIONS

The findings of this study show that a high DII and E-DII were associated with an increased incidence of constipation among US adults.

Dietary inflammatory index and its association with risk of metabolic syndrome and its components: a systematic review and Meta-analysis of Observational studies

BACKGROUND

It is believed that the progression and development of metabolic syndrome (MetS) are associated with low-grade systemic inflammation. Several studies have suggested that the Dietary Inflammatory Index (DII), which estimates the inflammatory potential of diets, is associated with MetS. This systematic review and meta-analysis aimed to determine the relationships between DII and the MetS and its components.

METHODS

Relevant articles published in English from inception to May 2024 were identified by searching electronic databases including PubMed, Scopus, and Web of Science. We included studies that reported the odds ratio (OR), relative risk (RR), or hazard ratio for the association of DII with the MetS and its components. Effect sizes were pooled using a random effects model.

RESULTS

A total of three prospective studies and 22 cross-sectional studies were included in this meta-analysis. The results showed that pro-inflammatory diets were significantly associated with an increased risk of MetS in cohort studies (RR: 1.33; 95% confidence interval [CI]: 1.19-1.48) and cross-sectional studies (OR:1.24; 95% CI: 1.11-1.38). Meta-analysis of cross-sectional studies showed that a higher DII score was significantly associated with higher odds of hypertension (OR = 1.19; 95% CI = 1.10-1.28) and hyperglycemia (OR = 1.18; CI = 1.06-1.32). The pooled OR comparing the highest versus lowest category of DII with the odds of abdominal obesity and hypertriglyceridemia was significant only after adjustment for covariates.

CONCLUSIONS

In general, higher DII is associated with a higher risk of MetS and some of its components. Based on the findings, dietary interventions should be considered for preventing MetS from the inflammatory perspective.

The dietary inflammatory index and cardiometabolic parameters in US firefighters

Introduction

Dietary choices play a crucial role in influencing systemic inflammation and the eventual development of cardiovascular diseases (CVD). The Dietary Inflammatory Index (DII®) is a novel tool designed to assess the inflammatory potential of one's diet. Firefighting, which is characterized by high-stress environments and elevated CVD risk, represents an interesting context for exploring the dietary inflammatory-CVD connection.

Aim

This study aims to investigate the associations between Energy-adjusted Dietary Inflammatory Index (E-DII™) scores and cardiometabolic risk parameters among US firefighters.

Methods

The study analyzed 413 participants from the Indianapolis Fire Department who took part in a Federal Emergency Management Agency (FEMA)-sponsored Mediterranean diet intervention trial. Thorough medical evaluations, encompassing physical examinations, standard laboratory tests, resting electrocardiograms, and submaximal treadmill exercise testing, were carried out. Participants also completed a detailed food frequency questionnaire to evaluate dietary patterns, and E-DII scores were subsequently computed based on the gathered information.

Results

Participants had a mean body mass index (BMI) of 30.0 ± 4.5 kg/m2 and an average body fat percentage of 28.1 ± 6.6%. Regression analyses, adjusted for sex, BMI, maximal oxygen consumption (VO2 max), max metabolic equivalents (METS), age, and body fat percentage, revealed significant associations between high vs. low E-DII scores and total cholesterol (β = 10.37, p = 0.04). When comparing low Vs median E-DII scores there is an increase in glucose (β = 0.91, p = 0.72) and total cholesterol (β = 5.51, p = 0.26).

Conclusion

Our findings support an association between higher E-DII scores and increasing adiposity, as well as worse lipid profiles.

Dietary inflammatory index is associated with metabolic dysfunction-associated fatty liver disease among United States adults

Background

Metabolic dysfunction-associated fatty liver disease (MAFLD) is presently the most prevalent chronic liver disorder globally that is closely linked to obesity, dyslipidemia metabolic syndrome, and type 2 diabetes mellitus (T2DM). Its pathogenesis is strongly associated with inflammation, and diet is a major factor in reducing inflammation. However, current research has focused primarily on exploring the relationship between diet and NAFLD, with less research on its link to MAFLD.

Methods

In this research, using dietary inflammatory index (DII) as a measure to assess dietary quality, we analyzed the relationship between diet and MAFLD. Data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018, including 3,633 adults with complete DII and MAFLD, were used to develop cross-sectional analyses. Logistic regression analysis was adapted for investigating the relationship between DII and MAFLD development. Additionally, subgroup analysis and threshold effect analysis were carried out.

Results

A positive link between DII and MAFLD was found in the fully adjusted model (OR = 1.05; 95%CI, 1.00-1.11, p < 0.05). Subgroup analysis indicated that there was no significant dependence for the connection between DII and MAFLD except for the subgroup stratified by age. Compared with other age groups, people with MAFLD had 20% higher DII scores than non-MAFLD participants in those aged 20-41 years old (OR = 1.20; 95%CI, 1.08-1.33, p < 0.001). Furthermore, we found a U-shaped curve with an inflection point of 3.06 illustrating the non-linear connection between DII and MAFLD.

Conclusion

As a result, our research indicates that pro-inflammatory diet may increase the chance of MAFLD development, thus improved dietary patterns as a lifestyle intervention is an important strategy to decrease the incidence of MAFLD.

Inflammation mediates the relationship between diet quality assessed by healthy eating index-2015 and metabolic syndrome

Background

Metabolic syndrome is a cluster of metabolic disorders, including obesity, hypertension, hyperglycemia, and abnormal lipid levels. However, researches on the association between overall dietary quality measured by the Healthy Eating Index-2015 (HEI-2015) and the risk of metabolic syndrome is still lacking.

Methods

This study utilized data from four cycles (2011-2018) of the National Health and Nutrition Examination Survey (NHANES) database, including 17,582 participants. Logistic regression analysis was employed to explore the correlation between HEI and the risk of metabolic syndrome. Additionally, mediation analysis was conducted to examine the effects of Systemic Immune-Inflammation Index (SII) and serum uric acid as potential mediators between HEI and metabolic syndrome risk. Weighted quantile sum (WQS) regression evaluated the composite exposure impact of the 13 components of the HEI on metabolic syndrome, as well as the proportion of their weights.

Results

Higher dietary quality measured by HEI-2015 (at the 75th percentile) was negatively correlated with the risk of metabolic syndrome (OR=0.80, 95%CI=0.72-0.89, P=0.003). Higher SII and serum uric acid levels were identified as risk factors for metabolic syndrome (P for trend<0.001). Approximately 37.5% of the effect of HEI on metabolic syndrome occurrence was mediated by SII (Indirect effect=-0.002, 95%CI (-0.003,-0.001), Direct effect=-0.022, 95%CI (-0.0273,-0.015)). Additionally, 25% of the effect of HEI on metabolic syndrome occurrence was mediated by serum uric acid levels (Indirect effect=-0.006, 95%CI (-0.010,-0.012), Direct effect=-0.024, 95%CI (-0.041,-0.009)). WQS regression analysis revealed the highest weighted proportions for seafood and plant proteins (25.20%) and sodium (17.79%), while the weight for whole fruit was the lowest (0.25%).

Conclusion

Better dietary quality measured by HEI-2015 was associated with a lower likelihood of metabolic syndrome. Higher SII and serum uric acid levels were identified as risk factors for metabolic syndrome and potential mediators.

Association of dietary inflammatory index with all-cause and cardiovascular disease mortality in hyperuricemia population: A cohort study from NHANES 2001 to 2010

Dietary management is a crucial component of non-pharmacological treatment for hyperuricemia, yet there is a paucity of research on the impact of dietary habits on the survival outcomes of individuals with hyperuricemia. The objective of this study is to examine the association between dietary inflammatory index (DII) and the all-cause and cardiovascular disease (CVD) mortality in individuals with hyperuricemia. This study included 3093 adult participants from National Health and Nutrition Examination Survey (NHANES) 2001 to 2010. Participants were categorized into 4 groups based on quartiles of DII to demonstrate data characteristics, with sample weights considered. The relationship between DII and the risk of hyperuricemia was examined using multivariable logistic regression models. Kaplan-Meier models and Cox proportional hazards models were employed to assess the relationship between DII levels and the all-cause mortality in individuals with hyperuricemia, with the non-linear relationship tested using restricted cubic splines (RCS). Competing risk models were employed to investigate the association between DII levels and the CVD mortality in individuals diagnosed with hyperuricemia. Subgroup and sensitivity analysis were performed to confirm the robustness and reliability of the findings. Among the participants, 47.95% were aged over 60 years. A positive association observed between the highest quartile of DII level and the incidence of hyperuricemia (OR: 1.34, CI [1.13, 1.57]). Elevated DII levels were correlated with increased all-cause mortality (P value < .001) and CVD mortality (P value < .001) in participants. In comparison to the lowest quartile, the highest quartile of DII exhibited a 31% rise in all-cause mortality (HR: 1.31, CI [1.01, 1.68]) and a 50% increase in CVD mortality (HR: 1.50, CI [1.00, 2.26]). No indication of a nonlinear association between DII levels and all-cause mortality (p-non-linear = .43). These findings indicate a positive correlation between the pro-inflammatory diet and the incidence of hyperuricemia. Additionally, a pro-inflammatory diet may elevate the all-cause and CVD mortality in individuals with hyperuricemia.

17-year follow-up of association between telomere length and all-cause mortality, cardiovascular mortality in individuals with metabolic syndrome: results from the NHANES database prospective cohort study

BACKGROUND

The relationship between leukocyte telomere length (LTL) and mortality risk in individuals with metabolic syndrome (MetS) remains poorly understood. This study aimed to investigate the association between telomere length and long-term all-cause mortality, and cardiovascular disease (CVD) mortality, in individuals with MetS in the United States.

METHODS

A total of 1980 participants with MetS aged 18 years or older from the National Health and Nutrition Examination Survey (NHANES) prospective cohort study (1999-2002) were included in this cohort study. Medical records review was used to identify the cause of deaths as of December 2018. We employed Kaplan-Meier curves, fitted curves, and Cox proportional hazards regression models to estimate hazard ratios (HRs) for all-cause and CVD mortality, stratified by tertiles of LTL.

RESULTS

Over a median follow-up of 17.75 years of participants with metabolic syndrome, 819 deaths occurred, including 231 cardiovascular deaths. After adjusting for multiple covariates, participants with shorter telomere length had a significantly higher risk of all-cause mortality (HR, 1.33; 95% CI, 1.11-1.6) and CVD mortality (HR, 1.36; 95% CI, 0.96-1.93) compared with those in the highest tertile of telomere length. All-cause mortality (P < 0.001) and cardiovascular disease mortality (P = 0.028) followed a similar pattern across tertiles of telomere length.

CONCLUSION

In individuals with MetS, shorter telomere length is associated with increased risks of death from cardiovascular disease and all causes. The underlying mechanisms and clinical implications of these findings require additional investigation.

The association between dietary inflammation index and bone mineral density: results from the United States National Health and nutrition examination surveys

OBJECTIVE

To investigate the associations of dietary inflammation index (DII) with bone density and osteoporosis in different femoral areas.

METHODS

The study population was selected from the National Health and Nutrition Examination Survey (NHANES) with the exclusion criteria of age 18, pregnancy, or missing information on DII, femoral bone marrow density (BMD), estimated glomerular filtration rate (eGFR), and urine albumin-to-creatinine ratio (UACR), or had diseases which may influence systemic inflammation. DII was calculated based on the questionnaire interview of dietary recall within 24 h. Subjects' baseline characteristics were collected. The associations between DII and different femoral areas were analyzed.

RESULTS

After applying exclusion criteria, 10,312 participants were included in the study. Significant differences among DII tertiles were found in BMD or T scores (p < .001) of the femoral neck, the trochanter, the intertrochanter, and the total femur. High DII was associated with low BMDs and T scores in all the femoral areas (all p < .01). Compared to low DII (tertile1, DII < 0.380 as reference), in the femoral neck, the intertrochanter, and the total femur, increased DII is independently associated with increased the possibility of the presence of osteoporosis (OR, 95% CI: 1.88, 1.11-3.20; 2.10, 1.05-4.20; 1.94, 1.02-3.69, respectively). However, this positive association was only observed in the trochanteric area of the non-Hispanic White population after full adjustment (OR, 95% CI: 3.22 (1.18, 8.79)). No significant difference in the association of DII and the presence of osteoporosis were found in subjects with or without impaired kidney function (eGFR < 60 ml/min/1.73 m²).

CONCLUSION

High DII is independently related to declined femoral BMD of femoral areas.

Association between dietary inflammation index and hypertension in participants with different degrees of liver steatosis

BACKGROUND

The prevalence of hypertension (HTN) is higher in patients with non-alcoholic fatty liver disease (NAFLD). Inflammation is the key link between HTN and NAFLD. Systemic inflammation can be dramatically increased by inflammatory diet intake. However, whether controlling the inflammatory diet intake in NAFLD patients could affect the occurrence of HTN still remains unknown. Our aim here is to evaluate the effect of the dietary inflammatory index (DII) on blood pressure in patients with different grades of hepatic steatosis.

MATERIALS AND METHODS

The data were collected from the National Health and Nutrition Examination Survey (NHANES) (2017-2018). DII was calculated based on the data of 24-h dietary recall interviews. The severity of liver steatosis was assessed by a controlled attenuation parameter. Multivariable logistic regression, multivariable linear regression and subgroup analyses were conducted to determine the association between DII and blood pressure in patients with different degrees of hepatic steatosis.

RESULTS

A total of 5449 participants were included in this analysis. In male participants with severe liver steatosis (S3), the highest DII tertile group was more likely to have higher systolic blood pressure (SBP) compared with the lowest tertile group (Tertile1: 128.31(125.31,131.31), Tertile3: 133.12(129.40,136.85), P for trend =0.03551). DII was positively correlated with SBP and the prevalence of HTN in males with hepatic steatosis grade S3 (≥ 67% steatosis) (SBP: P for trend = 0.011, HTN: P for trend = 0.039). Regarding the association of DII with SBP and HTN, the tests for interaction were significant for hepatic steatosis (SBP: interaction for p = 0.0015, HTN: interaction for p = 0.0202).

CONCLUSIONS

In the present study, we demonstrated that DII was a risk factor for increased SBP and the prevalence of HTN in males with severe hepatic steatosis S3, indicating that anti-inflammatory dietary management should be considered in these individuals to reduce the risk of developing HTN.

Association between systemic immune-inflammation index and metabolic syndrome and its components: results from the National Health and Nutrition Examination Survey 2011-2016

BACKGROUND

Metabolic syndrome (MetS), a worldwide public health problem, affects human health and quality of life in a dramatic manner. A growing evidence base suggests that MetS is strongly associated with levels of systemic immune inflammation. The present study aimed to investigate the possible relationship between the systemic immune-inflammation index (SII), a novel inflammatory marker, and MetS to provide data support for effective MetS prevention by reducing the systemic inflammatory response.

METHODS

We included adult participants with complete SII and MetS information from the 2011-2016 National Health and Nutrition Examination Survey (NHANES). MetS was defined as using the criteria developed by the Adult Treatment Program III of the National Cholesterol Education Program. The formula for SII was as follows: SII = platelet counts × neutrophil counts/ lymphocyte counts. Weighted linear regression was used to assess differences in variables across SII quartile groups after the SII score was divided into 4 quartiles. The independent interaction between SII and MetS was investigated using weighted multivariate logistic regression analysis and subgroup analysis, and the relationship between SII levels and 5 particular MetS items was further explored in depth.

RESULTS

A total of 12,402 participants, 3,489 of whom were diagnosed with MetS, were included in this study. After correcting for covariates, the results of a logistic regression of multistage weighted complex sampling data revealed that participants with higher SII scores had a higher chance of developing MetS (odds ratio (OR) = 1.33, 95% confidence interval (CI): 1.14-1.55) and that SII levels could be used as an independent risk factor to predict that likelihood of MetS onset. In the Q1-Q4 SII quartile group, the risk of developing MetS was 1.33 times higher in the Q4 group, which had the highest level of systemic immune inflammation than in the Q1 group. After adjusting for all confounding factors, SII scores were found to have a negative correlation with high-density lipoprotein cholesterol (OR = 1.29; 95% CI, 0.99-1.67, P = 0.056) and a significant positive correlation with waist circumference (OR = 2.17; 95% CI, 1.65-2.87, P < 0.001) and blood pressure (BP) (OR = 1.65; 95% CI, 1.20-2.27, P = 0.003). Gender, age, and smoking status were shown to alter the positive association between SII and MetS in subgroup analyses and interaction tests (p for interaction < 0.05). Additionally, we demonstrated a nonlinear correlation between SII and MetS. The findings of the restricted cubic spline indicated that there was an inverted U-shaped association between SII and MetS.

CONCLUSIONS

Our findings imply that increased SII levels are related to MetS, and SII may be a simple and cost-effective method to identify individuals with MetS. Therefore, protective measures such as early investigation and anti-inflammatory interventions are necessary to reduce the overall incidence of MetS.

How Does Dietary Intake Relate to Dispositional Optimism and Health-Related Quality of Life in Germline BRCA1/2 Mutation Carriers?

Background: The Mediterranean diet (MD) is an anti-inflammatory diet linked to improved health-related quality of life (HRQoL). Germline (g)BRCA1/2 mutation carriers have an increased risk of developing breast cancer and are often exposed to severe cancer treatments, thus the improvement of HRQoL is important. Little is known about the associations between dietary intake and HRQoL in this population. Methods: We included 312 gBRCA1/2 mutation carriers from an ongoing prospective randomized controlled lifestyle intervention trial. Baseline data from the EPIC food frequency questionnaire was used to calculate the dietary inflammatory index (DII), and adherence to MD was captured by the 14-item PREDIMED questionnaire. HRQoL was measured by the EORTC QLQ-C30 and LOT-R questionnaires. The presence of metabolic syndrome (MetS) was determined using anthropometric measurements, blood samples and vital parameters. Linear and logistic regression models were performed to assess the possible impact of diet and metabolic syndrome on HRQoL. Results: Women with a prior history of cancer (59.6%) reported lower DIIs than women without it (p = 0.011). A greater adherence to MD was associated with lower DII scores (p < 0.001) and reduced odds for metabolic syndrome (MetS) (p = 0.024). Women with a more optimistic outlook on life reported greater adherence to MD (p < 0.001), whereas a more pessimistic outlook on life increased the odds for MetS (OR = 1.15; p = 0.023). Conclusions: This is the first study in gBRCA1/2 mutation carriers that has linked MD, DII, and MetS to HRQoL. The long-term clinical implications of these findings are yet to be determined.

Association between dietary inflammatory index and atherosclerosis cardiovascular disease in U.S. adults

Objective

To evaluate the association between dietary inflammatory index (DII) and Atherosclerotic cardiovascular disease (ASCVD) among U.S. adults.

Methods

We collected data from National Health and Nutrition Examination Survey (NHANES) between 1999 and 2018. Adults who reported complete information to diagnose ASCVD and calculate DII were included. We used three models to differentially adjust the covariates, including age, sex, race or ethnicity, education level, smoking status, poverty, insurance, body mass index, hyperlipemia, hypertension, and diabetes. Logistic regression was used to estimate the Odds Ratio (OR) and 95% confidence interval (95% CI) for ASCVD grouped by DII deciles. We additionally conducted spline smoothing with the generalized additive model (GAM) and the log-likelihood ratio to examine the non-linear relationship between DII and ASCVD. If exists, the segmented linear regression will be used to detect the cutoff point. The subgroup analyses were stratified by various atherosclerotic cardiovascular diseases (i.e., CHD, angina, heart attack, and stroke) and sex.

Results

A total of 48,733 participants (mean age, 47.13 ± 0.19 years) with 51.91% women were enrolled, of which 5,011 were diagnosed with ASCVD. In the crude model, participants in the five highest deciles (D6, 7, 8, 9, and 10) of DII score had a significantly higher risk of having ASCVD compared to those in the first decile. In the fully adjusted model, those in the tenth decile [OR = 1.47, 95% CI = (1.18,1.84)] of DII had a significantly increased risk of ASCVD compared to the first decile. Notably, when DII is above 3, the ASCVD risk increased by 41% for each one increase in DII [OR = 1.41, 95% CI = (1.15,1.73)]. This relationship was more pronounced in females.

Conclusion

Our study revealed a positive and non-linearly association between DII and ASCVD in U.S. adults. This relationship was more pronounced in females. The findings provide a reference for future research and diet recommendations.