Association of Dietary Inflammatory Index (DII) and depression in the elderly over 55 years in Northern China: analysis of data from a multicentre, cohort study

The Relationship of Certain Diseases and Dietary Inflammatory Index in Older Adults: A Narrative Review

PURPOSE OF REVIEW

One of the important markers affecting aging processes is the increase in inflammatory markers. Many chronic diseases are associated with inflammation and chronic inflammation increases with aging. Inflammation can change with dietary components. Foods, compounds and nutrients that have anti-inflammatory or proinflammatory properties attract attention. According to the Dietary Inflammatory Index, positive scores are obtained if the nutrient has a proinflammatory effect on cytokines, and negative scores are obtained if it has an anti-inflammatory effect.

RECENT FINDINGS

A higher proinflammatory diet is associated with cardiometabolic diseases, neurodegenerative disease, cancers and musculoskeletal health and related mortality. In this study, its relationship with type 2 diabetes mellitus, obesity, metabolic syndrome, musculoskeletal diseases, dementia, depression and cancer, which are more common in older adults and known to be associated with inflammation, was examined. Although studies involving under 65 years old are more prevalent, research involving older adults and Dietary Inflammatory Index (DII) is more limited. It is known that chronic inflammation increases with aging. Diet is one of the factors affecting inflammation. In the light of these investigations, the topics of anti-inflammatory nutrition and DII for the treatment of inflammation-related diseases in older adults are strong and open to development topics of discussion. Despite the significant interest in the potential positive effects of anti-inflammatory nutrition on diseases, contributing to clearer evidence of its protective effects on health necessitates further randomized controlled trials, in vivo, in vitro, cell, animal, human and case-control studies for better risk assessment.

Systemic inflammation mediates the association between environmental tobacco smoke and depressive symptoms: A cross-sectional study of NHANES 2009-2018

BACKGROUND

Depression is associated with both environmental tobacco smoke (ETS) and inflammation. However, whether systemic inflammation mediates the ETS-depression relationship is unclear.

METHODS

We analyzed 19,612 participants from the 2009-2018 National Health and Nutrition Examination Survey (representing approximately 206,284,711 USA individuals), utilizing data of depressive symptoms (assessed by Patient Health Questionnaire-9), blood cotinine level (an ETS biomarker), dietary inflammatory index (DII, assessed by 24-h dietary recall) and inflammation, represented by immune-inflammation index (SII) and systemic inflammation response index (SIRI).

RESULTS

Weighted multivariable logistic regression showed that a higher blood cotinine level is significantly associated with a higher depressive symptoms risk (OR = 1.79, 1.35-2.38). After adjusting for covariates, the effect in smokers (OR = 1.220, 95 % CI: 1.140-1.309) is larger than that in non-smokers (OR = 1.150, 95 % CI: 1.009-1.318). Compared to the lowest level, depressive symptoms risks in participants with the highest level of SII, SIRI and DII are 19 % (OR = 1.19, 1.05-1.35), 15 % (OR = 1.15, 1.01-1.31) and 88 % (OR = 1.88, 1.48-2.39) higher, respectively. Weighted linear regression demonstrated positive correlations of SII (β = 0.004, 0.001-0.006), SIRI (β = 0.009, 0.005-0.012) and DII (β = 0.213, 0.187-0.240) with blood cotinine level. Restricted cubic splines model showed a linear dose-response relationship between blood cotinine and depressive symptoms (Pnon-linear = 0.410), with decreasing risk for lower DII. And SII and SIRI respectively mediate 0.21 % and 0.1 % of the association between blood cotinine and depressive symptoms.

LIMITATION

Cross-sectional design, and lack of medication data for depression.

CONCLUSIONS

Positive association of ETS (blood cotinine) with depressive symptoms risk is partly mediated by systemic inflammation, and anti-inflammatory diet could be beneficial.

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

Introduction

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

Methods

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

Results

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

Conclusion

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

Relationship between Dietary Inflammatory Index and Postpartum Depression in Exclusively Breastfeeding Women

(1) Background: Research has shown that chronic inflammation can increase the risk of depression. The dietary inflammatory index (DII) is a novel measure of dietary inflammation, which has been used to investigate the relationship between diet and mental disorders in adults. However, little research has been conducted to establish an association between dietary inflammation (as measured by DII) and postpartum depression (PPD) in exclusively breastfeeding women. (2) Methods: In this cross-sectional study, 293 women who were exclusively breastfeeding for 6 months or less were enrolled. The DII scores were evaluated using semi-quantitative Food Frequency Questionnaires (FFQ), and the Edinburgh Postpartum Depression Scale (EPDS) was used to measure depression levels of breastfeeding mothers during the six months following delivery. The participants were classified by tertiles, and the possibility of DII being associated with PPD was assessed by binary regression analysis. (3) Results: The average DII score was 2.32 ± 1.08, which ranged from -1.66 to 4.19. The rate of depression was 60.1%. Adjusted for potential risk factors such as age, educational level, occupational level, number of babies, number of caregivers, social support level, and sleep quality, the results showed that the lowest DII score was associated with a lower risk of PPD than the highest score (OR tertile Q₁ vs. 3 = 0.47, 95% CI: 0.24, 0.93, p = 0.030). (4) Conclusions: In exclusive breastfeeding women, the inflammatory potential of dietary intake seems to be related to depression. Interventions to improve diet quality might consider including a dietary component that aims to lower chronic systemic inflammation to prevent PPD. However, the relationship between DII and PPD among Chinese women remains to be demonstrated in a larger population.