A new meta-analysis has reported that individuals with a high triglyceride-glucose index have a 41% greater likelihood of suffering from depression compared to those with lower values of this index. These results remained consistent across individuals both above and below 50 years of age, as well as across different genders. The research was published in Frontiers in Psychiatry.
Depression is a common mental health disorder characterized by persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. The severity of depression can vary, and it can be influenced by a variety of genetic, biological, environmental, and psychological factors. Factors associated with an increased risk of depression include genetic predisposition, chronic stress, trauma, and significant life changes such as loss or illness. Additionally, underlying medical conditions, substance abuse, and social isolation can also contribute to the likelihood of developing depression.
Recent studies have also linked an increased risk of depression to obesity and type 2 diabetes. The key underlying issue with type 2 diabetes is insulin resistance, a condition in which the body’s cells become less responsive to the hormone insulin, leading to impaired glucose uptake and elevated blood sugar levels. Recently, a novel indicator of insulin resistance, the triglyceride-glucose index, was developed. This index is calculated from serum triglyceride and fasting plasma glucose values.
Triglycerides are a type of fat present in the blood, while fasting plasma glucose values indicate the amount of glucose (a simple sugar that serves as the primary source of energy for the body’s cells) in the blood after a period of fasting. Both are important indicators of metabolic health.
Study authors Weitao Wan and Yi Yu sought to evaluate the association between the triglyceride-glucose index and depression in the adult population. They noted that results reported in previous studies were inconsistent, which motivated them to integrate these findings by conducting a meta-analysis.
The authors searched Medline, Web of Science, Embase, Wanfang, and China National Knowledge Internet databases using various terms related to the triglyceride-glucose index and depression. They focused on studies conducted on adults without specific diagnoses or somatic diseases that reported data on both depression and the triglyceride-glucose index.
The search yielded 67 potentially relevant texts. Upon closer inspection, six studies met all the necessary criteria and provided the required data for inclusion in the analysis. These six studies included eight datasets involving a total of 28,973 adults.
The number of participants per study ranged from 387 to 13,350, with 77% of participants coming from just the two largest studies. The proportion of participants with depression varied widely, ranging from 7% to over 50%. The mean age of study participants ranged from 44 to 59 years.
The results showed that individuals with high triglyceride-glucose index values had 41% higher odds of depression compared to those with lower values. The variability of these odds across studies was relatively small. The results were consistent among individuals both above and below 50 years of age and across different genders.
“Although large-scale prospective studies are needed to validate the results, the findings of this meta-analysis support the potential association between a high TyG [triglyceride glucose] index and the prevalence of depression in general population,” the study authors concluded.
The study highlights the potential links between depression and triglyceride-glucose index values. However, it is important to note that the proportion of individuals with depression in several of the studies included in the analysis was much higher than in the general population. While common estimates suggest that the lifetime prevalence of depression in the population is between 5% and 17%, three of the studies in this meta-analysis reported depression rates near or above 50%, while one study did not report this information.
The paper, “Association between the triglyceride glucose index and depression: a meta-analysis,” was authored by Weitao Wan and Yi Yu.