Pro-Inflammatory Biomarkers And Depression: A Study Performed In A Group Of Health Sciences University Students

Depression is one of the most prevalent mental illnesses worldwide, and its etiology is still the subject of multiple studies that strive to clearly identify the causes of this disorder and guide the appropriate form of treatment. The present study aimed to establish the correlation between elevated levels of circulating proinflammatory cytokines such as interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) with depression.

An analytical correlational study was conducted in which 300 medicine and nursing students from a university in the city of Loja, Ecuador participated. They were assessed with the Beck Depression Inventory II (BDI II) to determine the presence of depression, and peripheral levels of interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were measured using the ELISA technique.

65% of the participants reported depression according to the Beck Depression Inventory II, which in turn were divided into mild (23%), moderate (20.3%) and severe depression (21.7%) according to the score obtained. A statistically significant correlation was found between elevated levels of IL-6 and TNF-α with depression in the group of nursing students. However, no such correlation was found in the group of medical students.

Elevations in both inflammatory cytokines measured in this study were evident in both study groups. This could be explained by the high emotional stress generally associated with healthcare career training, which in turn could reinforce the hypothesis of inflammatory states and their relation to the pathophysiology of depression. However, the percentage of depression cases was higher in the nursing student group, in which the female gender accounted for 83.3% of the group, a fact that could explain the reason why in this group there was a statistically significant relationship between elevated cytokines and the presence of depression.