Longitudinal association between triglyceride glucose index and depression progression in middle-aged and elder adults: A national retrospective cohort study

Reduced brain modularity may underlie accelerated disease progression in first-episode, drug-naïve depression

BACKGROUND

Depression presents considerable heterogeneity in its clinical course, yet reliable biomarkers for predicting individual trajectories remain elusive. Brain modularity, a fundamental topological property of structural networks, reflects the balance between functional segregation and integration. This study investigates the prognostic significance of brain modularity in depression progression and its association with white matter alterations.

METHODS

In this longitudinal study, 142 first-episode, medication-naïve patients with depression underwent diffusion MRI-based structural network analysis. Based on baseline modularity values, participants were stratified into high- and low-modularity groups. Key white matter network metrics-including rich-club connections, global efficiency, and nodal efficiency-were assessed. Depression severity was measured using the Hamilton Depression Rating Scale (HDRS). Logistic regression and receiver operating characteristic (ROC) analyses were employed to evaluate the prognostic utility of brain modularity in predicting symptom progression.

RESULTS

At baseline, patients with lower modularity exhibited disrupted network organization. Longitudinally, these individuals showed a steeper decline in rich-club connections, global efficiency, and left hippocampal nodal efficiency, alongside significantly greater HDRS worsening. Baseline modularity was inversely correlated with the rate of depression progression, with logistic regression confirming its predictive value. ROC analysis demonstrated robust classification performance.

CONCLUSIONS

Reduced brain modularity predisposes individuals to accelerated white matter network alterations and worsening depressive symptoms. These findings highlight brain modularity as a potential biomarker for identifying individuals at heightened risk of depression progression, offering a novel target for early intervention.

Triglyceride-glucose index and its association with depressive symptoms in older adults: a longitudinal analysis

BACKGROUND

The triglyceride-glucose index (TyG) has been proposed as a promising and clinically relevant biological marker of insulin resistance, which is thought to be prevalent among individuals at risk for depression. To date, there have been no longitudinal studies investigating the relationship between an elevated triglyceride-glucose index and subsequent depressive symptoms.

METHODS

Health measures of 19,114 community-dwelling adults living in Australia and the United States of America, with a mean age of 75 years, were followed up for up to 11 years. Fasting triglyceride levels and fasting glucose levels were used to calculate the triglyceride-glucose index (TyG - the logarithmised product of fasting triglyceride level and fasting glucose divided by two), a marker of insulin resistance and risk for atherosclerotic cardiovascular disease. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression 10-item scale (CES-D-10), with a score ≥ 8 used to indicate a diagnosis of depression. The association between TyG and depression one year later was assessed using generalized estimating equations (GEE), with robust variance estimation to handle repeated measures clustered data. The main model was adjusted for age, gender, ethnicity, living arrangements, education, smoking status, alcohol consumption, body mass index, hypertension, type 2 diabetes, chronic kidney disease, a history of cancer, modified mini-mental state examination score, aspirin use, antidepressant use, diabetic medication use, and lipid-lowering medication use. In a secondary analysis, a Cox proportional hazards model was used to compare the incidence of depression up to 11 years between individuals with the highest baseline TyG group and the lowest baseline TyG.

RESULTS

After adjustments for confounders, the GEE analysis showed no significant relationship between the highest quartile of TyG (compared to the lowest quartile of TyG) and depression one year later. The Cox proportional hazards model showed no significant difference between the highest and lowest TyG and depressive symptoms, when adjusted for the above covariates.

CONCLUSIONS

An elevated triglyceride-glucose index was not associated with the later development of depression in fully adjusted models.

Machine learning study on predicting depressive symptoms and genetic correlations in Parkinson's disease

Depressive symptoms are prevalent in individuals with Parkinson's disease. Previous research has demonstrated a significant association between the triglyceride glucose (TyG) index and depression. Leveraging multicenter clinical data, the present study evaluates the predictive capacity of the TyG index for depressive symptoms in PD patients, aiming to establish its potential role in identifying individuals at risk for depression. A comparative analysis of multiple machine learning models was conducted to predict depression in PD patients, ultimately selecting the most effective model. Key predictive variables, including diabetes status, sex, cholesterol levels, triglycerides, blood glucose, and sleep disturbances, were incorporated into a support vector machine (SVM)-based nomogram to assess depression risk in PD patients. Additionally, a genome-wide association study (GWAS) utilizing external databases confirmed a causal relationship between the TyG index and depression. Furthermore, this study explores the biological functions and molecular mechanisms underlying shared transcriptomic proteins between PD and depression, providing insights into potential pathophysiological links between the two conditions.

Association between triglyceride-glucose index and its combination with obesity indicators and depression: findings from NHANES 2005-2020

Background

The relationship between the triglyceride-glucose (TyG) index, its combination with obesity indicators, and depression remains understudied in the American population.

Methods

This cross-sectional study analyzed data from 10,423 adults in the National Health and Nutrition Examination Survey (NHANES) conducted between 2005 and 2020. We employed multivariable logistic regression analysis, smoothing techniques, generalized additive models, stratified analyses, and sensitivity analyses to examine the relationship between TyG, its combination (TyG-WC, TyG-WHtR, TyG-BMI) with obesity indicators, and depression.

Results

The results indicate that the TyG index, TyG-WC, TyG-WHtR, TyG-BMI, and depression exhibited a significant statistical association with depressive symptoms (all P for trend < 0.001). Specifically, a one-unit increase in the TyG index correlated with a 37% increase in the risk of depressive symptoms (95% CI: 1.21-1.55), a one-unit increase in TyG-WC correlated with a 3.26 times increase in the risk of depressive symptoms (95% CI: 2.22-4.80), a one-unit increase in TyG-WHtR correlated with a 27% increase in the risk of depressive symptoms (95% CI: 1.18-1.36), and a one-unit increase in TyG-BMI correlated with a 2.30 times increase in the risk of depressive symptoms (95% CI: 1.72-3.08). There was a significant nonlinear correlation between TyG-WC, TyG-WHtR, and TyG-BMI with depressive symptoms (all P for nonlinearity < 0.001), except for a linear correlation between the TyG index and depressive symptoms (P for linearity < 0.001).

Conclusion

Monitoring the TyG index, TyG-WC, TyG-WHtR, TyG-BMI may facilitate depression risk assessment and prevention.

Association between triglyceride-glucose (TyG) index and the incidence of depression in US adults with diabetes or pre-diabetes

BACKGROUND

The relationship between the triglyceride glucose (TyG) index and the incidence of depression in populations with diabetes or pre-diabetes remains unclear. This study aims to investigate the association between the TyG index and depression incidence in diabetic/pre-diabetic populations.

METHOD

Data from the 2005-2018 National Health and Nutrition Examination Survey (NHANES) were analyzed. After adjustment for confounders, multivariate logistic regression models were fitted to investigate the association between TyG index and depression incidence. Restricted cubic splines (RCS), subgroup analysis, interaction analysis, and mediation analysis were also constructed.

RESULTS

A total of 8,970 participants with diabetes or pre-diabetes were enrolled. The linear positive association between TyG index and the incidence of depression was observed. Insulin resistance partly mediates this association in mediation analysis. There is a U-shape association between TyG index and the incidence of depression in diabetic/pre-diabetic populations whose ethnicity is Other Hispanic (p for nonlinearity =0.0237). Subgroup analysis evaluated the robustness of our findings and interaction analysis showed that this association can be modified by race/ethnicity.

CONCLUSION

There is a linear positive association between the TyG index and the incidence of depression in populations with diabetes or pre-diabetes.

Association of TyG Index and TG/HDL-C Ratio with Trajectories of Depressive Symptoms: Evidence from China Health and Retirement Longitudinal Study

OBJECTIVES

To explore whether the triglyceride-glucose (TyG) index and the triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio are associated with the trajectories of depressive symptoms.

METHODS

In this longitudinal study, 4215 participants aged 45 years and older were recruited from the China Health and Retirement Longitudinal Study from 2011 to 2018. The trajectories of depressive symptoms, measured by the 10-item Center for Epidemiologic Studies Depression Scale (CESD-10), were identified using group-based trajectory modeling. Multinomial logistic models and restricted cubic spline analysis were used to investigate the relationships between the TyG index and the TG/HDL-C ratio and the trajectories of depressive symptoms. Stratified analyses were conducted based on sex, age, place of residence, and body mass index (BMI).

RESULTS

Five distinct trajectories of depressive symptoms characterized by stable low, stable moderate, decreasing, increasing, and stable high were identified during a follow-up of 7 years. The associations of the TyG index and the TG/HDL-C ratio with trajectories of depressive symptoms are not entirely consistent. After adjusting for covariates, a higher TyG index at baseline was associated with lower odds of being on the decreasing trajectory of depressive symptoms (ORad = 0.61, 95% CI: 0.40-0.92) compared to the stable low trajectory, and restricted cubic spline analysis revealed a negative linear relationship between the TyG index and the likelihood of a decreasing trajectory of depressive symptoms. However, the relationship between the TG/HDL-C ratio and the decreasing trajectory of depressive symptoms was no longer statistically significant when all confounders were controlled (ORad = 0.72, 95% CI: 0.50-1.04). Additionally, this negative association between the TyG index and decreasing trajectory of depressive symptoms was observed among 45-64-year-old individuals, female participants, those living in rural areas, and those with a normal BMI.

LIMITATIONS

This study was conducted in a middle-aged and elderly population in China, and extrapolation to other regions and populations requires further confirmation.

CONCLUSIONS

Compared to the TG/HDL-C ratio, the TyG index may be a better predictor for trajectories of depressive symptoms in middle-aged and older adults. Considering that the pathology of depression progresses long term, our findings may have utility for identifying available and reliable markers for the development of depression.

Role of Peripheral and Central Insulin Resistance in Neuropsychiatric Disorders

Insulin acts on different organs, including the brain, which helps it regulate energy metabolism. Insulin signaling plays an important role in the function of different cell types. In this review, we have summarized the key roles of insulin and insulin receptors in healthy brains and in different brain disorders. Insulin signaling, as well as insulin resistance (IR), is a major contributor in the regulation of mood, behavior, and cognition. Recent evidence showed that both peripheral and central insulin resistance play a role in the pathophysiology, clinical presentation, and management of neuropsychiatric disorders like Cognitive Impairment/Dementia, Depression, and Schizophrenia. Many human studies point out Insulin Resistance/Metabolic Syndrome can increase the risk of dementia especially Alzheimer's dementia (AD). IR has been shown to play a role in AD development but also in its progression. This review article discusses the pathophysiological pathways and mechanisms of insulin resistance in major neuropsychiatric disorders. The extent of insulin resistance can be quantified using IR biomarkers like insulin levels, HOMA-IR index, and Triglyceride glucose-body mass index (TyG-BMI) levels. IR has been shown to precede neurodegeneration. Human trials showed current treatment with certain antidiabetic drugs, as well as life style management, like weight loss and exercise for IR, have shown promise in the management of cognitive/neuropsychiatric disorders. This may pave the pathway to the development of new therapeutic approaches to these challenging disorders of dementia and psychiatric diseases. Recent clinical trials are showing some encouraging evidence for these pharmacological and nonpharmacological approaches for IR in psychiatric and cognitive disorders, even though more research is needed to apply this evidence into clinical practice. Early identification and management of IR may help as a strategy to potentially alter neuropsychiatric disorders onset as well as its progression.

Relationship between the triglyceride-glucose index and depression in individuals with chronic kidney disease: A cross-sectional study from National Health and Nutrition Examination Survey 2005-2020

Accumulating evidence indicates that individuals with chronic kidney disease (CKD) are at an increased risk of experiencing depressive disorders, which may accelerate its progression. However, the relationship between the triglyceride-glucose (TyG) index and depression in CKD individuals remains unclear. Therefore, this cross-sectional study aimed to assess whether such a relationship exists. To this end, the CKD cohort of the National Health and Nutrition Examination Survey from 2005 to 2020 was analyzed using multivariable logistic regression analyses and a generalized additive approach. A recursive algorithm was employed to pinpoint the turning point, constructing a dual-segment linear regression model. The study included 10,563 participants. After controlling for all variables, the odds ratios and 95% confidence intervals indicated a 1.24 (range, 1.09-1.42) relationship between the TyG index and depression in the CKD cohort. The findings underscored an asymmetrical association, with a pivotal value at a TyG index 9.29. Above this threshold, the adjusted odds ratio (95% confidence interval) was 1.10 (range, 0.93-1.31). This relationship was significant among the obese subgroups. The study results highlight the complex relationship between the TyG index and depression among American adults with CKD.

Triglyceride-glucose index as a potential predictor of major adverse cardiovascular and cerebrovascular events in patients with coronary heart disease complicated with depression

Background

Triglyceride-glucose (TyG) index is a surrogate marker of insulin resistance and metabolic abnormalities, which is closely related to the prognosis of a variety of diseases. Patients with both CHD and depression have a higher risk of major adverse cardiovascular and cerebrovascular events (MACCE) and worse outcome. TyG index may be able to predict the adverse prognosis of this special population.

Methods

The retrospective cohort study involved 596 patients with both CHD and depression between June 2013 and December 2023. The primary outcome endpoint was the occurrence of MACCE, including all-cause death, stroke, MI and emergent coronary revascularization. The receiver operating characteristic (ROC) curve, Cox regression analysis, Kaplan-Meier survival analysis, and restricted cubic spline (RCS) analysis were used to assess the correlation between TyG index and MACCE risk of in patients with CHD complicated with depression.

Results

With a median follow-up of 31 (15-62) months, MACCE occurred in 281(47.15%) patients. The area under the ROC curve of TyG index predicting the risk of MACCE was 0.765(0.726-0.804) (P<0.01). Patients in the high TyG index group(69.73%) had a significantly higher risk of developing MACCE than those in the low TyG index group(23.63%) (P<0.01). The multifactorial RCS model showed a nonlinear correlation (nonlinear P<0.01, overall P<0.01), with a critical value of 8.80 for the TyG index to predict the occurrence of MACCE. The TyG index was able to further improve the predictive accuracy of MACCE.

Conclusions

TyG index is a potential predictor of the risk of MACCE in patients with CHD complicated with depression.

The importance of assessing the triglyceride-glucose index (TyG) in patients with depression: A systematic review

Insulin resistance (IR) has been proposed as a potential risk factor for depression, a major common disorder affecting a significant proportion of adults worldwide. Based on this premise, this study systematically investigated all the studies examining the triglyceride-glucose (TyG) index, a surrogate marker of IR, in patients with depression or suicidal ideas/attempts. Four online databases (PubMed, Scopus, Embase, and Web of Science) were comprehensively searched. After screening, seven studies were included, comprised of 58,981 participants and 46.4% male. While there were some discrepancies among the reports of studies, most of the included studies reported higher levels of TyG index in patients with depression. Moreover, in most cases, a 1-unit increase in the TyG index was associated with significantly higher odds of depression. At last, higher TyG levels were associated with suicidal ideation and attempts. Therefore, this study emphasizes the critical need to further research in this regard and possibly integrate the TyG index measure with routine depression screening to avoid fatal events in the future.

Association between triglyceride glucose index (TyG) and psychotic symptoms in patients with first-episode drug-naïve major depressive disorder

OBJECTIVE

Major depressive disorder (MDD) sufferers frequently have psychotic symptoms, yet the underlying triggers remain elusive. Prior research suggests a link between insulin resistance (IR) and increased occurrence of psychotic symptoms. Hence, this study sought to investigate the potential association between psychotic symptoms in Chinese patients experiencing their first-episode drug-naïve (FEDN) MDD and the triglyceride glucose (TyG) index, an alternative measure of insulin resistance (IR).

METHODS

Between September 2016 and December 2018, 1,718 FEDN MDD patients with an average age of 34.9 ± 12.4 years were recruited for this cross-sectional study at the First Hospital of Shanxi Medical University in China. The study collected clinical and demographic data and included assessments of anxiety, depression, and psychotic symptoms using the 14-item Hamilton Anxiety Rating Scale (HAMA), the 17-item Hamilton Depression Rating Scale (HAMD-17), and the positive subscales of the Positive and Negative Syndrome Scale (PANSS), respectively. Measurements of metabolic parameters, fasting blood glucose (FBG), and thyroid hormones were also gathered. To assess the correlation between the TyG index and the likelihood of psychotic symptoms, the study used multivariable binary logistic regression analysis. Additionally, two-segmented linear regression models were employed to investigate possible threshold effects in case non-linearity relationships were identified.

RESULTS

Among the patients, 9.95% (171 out of 1,718) exhibited psychotic symptoms. Multivariable logistic regression analysis showed a positive correlation between the TyG index and the likelihood of psychotic symptoms (OR = 2.12, 95% CI: 1.21-3.74, P = 0.01) after adjusting for confounding variables. Moreover, smoothed plots revealed a nonlinear relationship with the TyG index, revealing an inflection point at 8.42. Interestingly, no significant link was observed to the left of the inflection point (OR = 0.50, 95% CI: 0.04-6.64, P = 0.60), whereas beyond this point, a positive correlation emerged between the TyG index and psychotic symptoms (OR = 2.42, 95% CI: 1.31-4.48, P = 0.01). Particularly, a considerable 142% rise in the probability of experiencing psychotic symptoms was found with each incremental elevation in the TyG index.

CONCLUSIONS

Understanding the non-linear link between the TyG index and the risk of psychotic symptoms in Chinese patients with FEDN MDD highlights the potential for targeted therapeutic approaches. By acknowledging the threshold effect observed, there is an opportunity to mitigate risk factors associated with IR-related psychiatric comorbidities through tailored interventions. These preliminary results stress the need for further longitudinal research to solidify these insights and contribute to more effective therapeutic strategies.

Association between triglyceride glucose index and depression in hypertensive population

Growing evidence suggests that hypertensive individuals have a greater risk of developing depression, and depression can also increase the incidence of hypertension. In the hypertensive population, the association between triglyceride glucose (TyG) index and depression remains unclear. This study aimed to assess the association between TyG index and depression in hypertensive people through the cross-sectional study of the National Health and Nutrition Examination Survey (2007-2018). To assess the relationship between TyG index and depression in hypertensive population, we conducted weighted multiple logistic regression models and used a generalized additive model to probe for nonlinear correlations. In addition, we employed a recursive algorithm to determine the inflection point and established a two-piece linear regression model. This study enrolled 5897 individuals. In the model adjusted for all covariates, the ORs (95% CI) for the relationship between TyG index and depression in hypertensive population were 1.32 (1.12-1.54). A nonlinear association was found between TyG index and depression, with an inflection point at 8.7. After the inflection point, the ORs (95% CI) were 1.44 (1.15-1.79). Only the interaction with the obese population was statistically significant. Our study highlighted a nonlinear association between TyG index and depression in American hypertensive adults.

Consolidating evidence on the role of insulin resistance in major depressive disorder

PURPOSE OF REVIEW

The circular interactions between type 2 diabetes (TMD2) and major depressive disorder (MDD) are well documented but the understanding of their mechanisms has only recently gained more clarity. Latest research indicates, that the association between TMD2 and MDD is largely mediated by insulin resistance (IR).

RECENT FINDINGS

A metabolic subtype of MDD can be distinguished from other MDD subpopulations, that is characterized by predominantly atypical clinical presentation, IR and different responsiveness to antidepressant interventions. IR is a predictor of nonresponse to some antidepressants. The IR seems to be a state-marker of clinical or subclinical depression and the relationship between IR and MDD varies between sexes and ethnicities. Insulin has a direct impact on the monoaminergic systems known to underlie MDD symptoms: serotoninergic and dopaminergic, which are dysregulated in IR subjects. Several trials assessed the efficacy of insulin-sensitizing drugs in MDD with mixed results for metformin and more consistent evidence for pioglitazone and lifestyle intervention/physical activity.

SUMMARY

Recently published data suggest a significant role of IR in the clinical presentation, pathophysiology and treatment response in MDD. Further research of IR in MDD and integration of existing data into clinical practice are needed.

Association between triglyceride glucose index and suicide attempts in patients with first-episode drug-naïve major depressive disorder

OBJECTIVE

Triglyceride glucose (TyG) index has been suggested as an alternative indicator of insulin resistance (IR); however, the association between TyG index and suicide attempts (SA) in major depressive disorder (MDD) is unclear. The aim of this study was to investigate the relationship between TyG index and SA in Chinese patients with first-episode drug-naïve (FEDN) MDD.

METHODS

This cross-sectional study enrolled 1,718 patients with FEDN MDD aged 34.9 ± 12.4 years from the First Hospital of Shanxi Medical University (Taiyuan, Shanxi Province, China) from September 2016 to December 2018. Multivariable binary logistic regression analysis was used to estimate the association between TyG index and the risk of SA. A two-piecewise linear regression model was used to investigate the threshold effects if non-linearity associations existed. Interaction and stratified analyses were performed based on sex, education, marital status, comorbid anxiety, and psychotic symptoms.

RESULTS

Multivariable logistic regression analysis revealed that TyG index was positively associated with the risk of SA after adjusting for confounders (OR = 1.35, 95% CI: 1.04-1.75, p = 0.03). Smoothing plots also showed a nonlinear relationship between TyG index and SA, with the inflection point of TyG index being 9.29. On the right of the inflection point, a positive association between TyG index and SA was detected (OR = 3.47, 95% CI: 1.81 to 6.66, p < 0.001), while no significant association was observed on the left side of the inflection point (OR = 1.14, 95% CI: 0.79 to 1.66, p = 0.476).

CONCLUSION

The relationship between TyG index and SA risk was non-linear and exhibited a threshold effect in Chinese patients with FEDN MDD. When TyG index was greater than 9.29, they showed a significant positive correlation.

Association of triglyceride-glucose index with major depressive disorder: A cross-sectional study

The triglyceride-glucose (TyG) index has been proposed as a new marker for insulin resistance, which is associated with a risk of major depressive disorder (MDD). This study aims to explore whether the TyG index is correlated with MDD. In total, 321 patients with MDD and 325 non-MDD patients were included in the study. The presence of MDD was identified by trained clinical psychiatrists using the International Classification of Diseases 10th Revision. The TyG index was calculated as follows: Ln (fasting triglyceride [mg/dL] × fasting glucose [mg/dL]/2). The results revealed that the MDD group presented higher TyG index values than the non-MDD group (8.77 [8.34-9.17] vs 8.62 [8.18-9.01], P < .001). We also found significantly higher morbidity of MDD in the highest TyG index group than in the lower TyG index group (59.9% vs 41.4%, P < .001). Binary logistic regression revealed that TyG was an independent risk factor for MDD (odds ratio [OR] 1.750, 95% confidence interval: 1.284-2.384, P < .001). We further assessed the effect of TyG on depression in sex subgroups. The OR was 3.872 (OR 2.014, 95% confidence interval: 1.282-3.164, P = .002) for the subgroup of men. It is suggested that the TyG index could be closely associated with morbidity in MDD patients; thus, it may be a valuable marker for identifying MDD.