The association between the dietary inflammatory index and gestational diabetes mellitus: A systematic review of observational studies

Association Between the Inflammatory Potential of Diet and Constipation Among Adults in the United States: A Cross-sectional Study

OBJECTIVE

To investigate the potential association between Dietary Inflammatory Index (DII) scores and constipation among a sample of adults in the United States.

METHODS

This cross-sectional study used data from adult participants in the 2005 to 2010 National Health and Nutrition Examination Survey (ie, "NHANES"). Self-reported information was used to identify cases of constipation. The DII was used to assess inflammatory potential of the diet. Odds ratios (ORs) and corresponding 95% CIs for the association between the DII and constipation were determined using multivariate logistic regression modeling. Stratified analyses explored whether there was effect modification to influence the relationship between DII and constipation.

RESULTS

Of 8272 subjects, 759 reported constipation, and 7513 did not, corresponding to a prevalence of 9.2%. After adjusting for age, gender, race/ethnicity, marital status, education level, smoking status, alcohol consumption, physical activity, body mass index (BMI), cardiovascular diseases (CVD), hypertension, stroke, diabetes, energy intake, carbohydrate intake, and selective serotonin reuptake inhibitor (SSRI) use. Compared with lower DII scores group T1 (-5.28 to ≤0.72), the adjusted OR values for DII scores and constipation in T2 (>0.72 to ≤2.50) and T3 (>2.50 to 5.24) were 1.27 (95% CI: 1.02-1.58, P=0.029) and 1.43(95% CI: 1.14-1.8, P=0.002). Subgroup analyses showed that there were effect modification of gender and physical activity factors on DII scores and constipation.

CONCLUSIONS

Results of this cross-sectional study suggest that a higher dietary inflammatory index score was associated with increased risk of constipation after adjustment for confounding in a multivariable analysis. gender and physical activity were found to be an effect modifier of this relationship.

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.

Association between dietary inflammation index and cataract: a population-based study from NHANES 2005-2008

Importance

Various studies have widely explored the association between index of dietary inflammation (DII) and occurrence of diseases. Accumulating evidence have revealed that a lower DII seems to be protective against a variety of diseases. Nevertheless, the association between DII and age-related cataract remains unclear.

Objective

To investigate the correlation between DII and age-related cataract in a representative sample of the American population.

Design setting and participants

This cross-sectional population-based study comprised 6,395 participants from the National Health and Nutrition Examination Survey (NHANES) conducted in cycles from 2005 to 2008. DII was calculated using dietary recall information, with higher scores indicating greater inflammatory potential of the diet. Age-related cataract was evaluated using cataract surgery as a surrogate measure. Covariates included sociodemographic factors, lifestyle factors, physical measures, and comorbidities. Logistic regression models were employed to assess the association between DII and cataract. The presence of a non-linear relationship was examined using restricted cubic spline analysis. Subgroup analysis was conducted to explore potential interaction effects. Data analysis was performed from September 1 to December 30, 2022.

Main outcomes and measures

Age-related cataract assessed through cataract surgery information obtained from a self-reported questionnaire.

Results

A total of 6,395 participants were included, with a mean (standard deviation, SD) age of 48.7 (15.3) years. Of these, 3,115 (48.7%) were male, 3,333 (52.1%) were non-Hispanic white, and 683 (10.7%) had cataract. The mean (SD) DII was -4.78 (1.74). After adjusting for all included covariates, DII showed a positive association with cataract, both as a continuous variable (odds ratio (OR): 1.054, 95% confidence interval (CI): 1.007-1.103, p = 0.023) and in quartiles, with the highest quartile compared to the lowest (OR: 1.555, 95% CI: 1.233-1.967, p < 0.001). Restricted cubic spline analysis revealed no evidence of a non-linear relationship (p for non-linearity 0.085). Subgroup analysis indicated no interaction effects among the studied covariates.

Conclusions and relevance

These findings suggest that a pro-inflammatory diet serves as a risk factor for the occurrence of cataracts.

Genetic Causal Relationship Between Alanine Aminotransferase Levels and Risk of Gestational Diabetes Mellitus: Mendelian Randomization Analysis Based on Two Samples

Gestational diabetes mellitus (GDM) is a frequent complication of pregnancy. The specific mechanisms underlying GDM have not yet been fully elucidated. Contemporary research indicates a potential association between liver enzyme irregularities and an increased risk of metabolic disorders, including diabetes. The alanine aminotransferase (ALT) level is recognized as a sensitive marker of liver injury. An increase in ALT levels is hypothesized to be linked to the pathogenesis of insulin resistance and diabetes. Nonetheless, the definitive causal link between ALT levels and GDM still needs to be determined. This investigation utilized two-sample Mendelian randomization (MR) to examine the genetic causation between alanine aminotransferase (ALT) and GDM. We acquired alanine aminotransferase (ALT)-related GWAS summary data from the UK Biobank, Million Veteran Program, Rotterdam Study, and Lifeline Study. Gestational diabetes data were obtained from the FinnGen Consortium. We employed various MR analysis techniques, including inverse-variance weighted (IVW), MR Egger, weighted median, simple, and weighted weighting. In addition to MR-Egger intercepts, Cochrane's Q test was also used to assess heterogeneity in the MR data, and the MR-PRESSO test was used to assess horizontal pleiotropy. To assess the association's sensitivity, a leave-one-out approach was employed. The IVW results confirmed the independent risk factor for GDM development, as indicated by the ALT level (p = .011). As shown by leave-one-out analysis, horizontal pleiotrophy did not significantly skew the causative link (p > .05). Our dual-sample MR analysis provides substantiated evidence of a genetic causal relationship between alanine aminotransferase (ALT) levels and gestational diabetes.

Impact of Weight Change on Glycemic Control and Metabolic Parameters in T2D: A Retrospective US Study Based on Real-World Data

INTRODUCTION

Weight loss has been identified as a key strategy for improving glycemic and metabolic outcomes in people with type 2 diabetes (T2D). However, the long-term, real-world impact of weight loss on these outcomes remains unclear. This study aimed to investigate (1) the association between weight loss and glycemic control, (2) association between weight loss and metabolic parameters, and (3) predictors of weight loss and how weight change trajectory varies based on index body mass index (BMI).

METHODS

A retrospective, longitudinal cohort study using the linked IQVIA Ambulatory electronic medical records and PharMetrics® Plus databases was performed from January 1, 2010 through December 31, 2019 in adults with T2D. Participants were categorized into 1-year and 5-year follow-up cohorts based on their observed weight change over time. Longitudinal values for vital signs and laboratory parameters, including BMI, weight, glycated hemoglobin (HbA1c), and metabolic parameters (liver enzymes and cholesterol), were reported at index date and every 6 months post index date. Multivariable logistic regression analysis was used to evaluate the factors associated with weight loss.

RESULTS

Of 1,493,964 people evaluated, 1,061,354 (71%) and 308,320 (20.6%) were classified into the 1-year and 5-year follow-up cohorts. Average HbA1c reductions of 1.2% and 0.5% were observed among people who lost ≥ 15% of index weight in the 1-year and 5-year follow-up cohorts, respectively. Higher weight loss percentages were associated with numerically greater improvements in metabolic parameters. The presence of bariatric surgery and higher index BMIs were identified as the strongest predictors of ≥ 15% and ≥ 10% weight loss in both follow-up cohorts.

CONCLUSION

Results from this study suggest that modest and sustained weight loss can lead to clinically meaningful improvements in glycemic and metabolic parameters among people with T2D. These findings highlight the importance of weight management in managing T2D and preventing its associated complications.