IL18 and depressive disorder: When comparing our results with studies that did not focus on people with diabetes, our data are in line with positive associations of the chemokine IL-8/CXCL8 and the proinflammatory cytokine IL-18 with depression that were found in previous meta-analyses based on study cohorts with a wide range of participant characteristics such as age, BMI and burden of comorbidities [13, 37].