Platelets are increasingly considered a bridge between mental and immunological disorders. However, data relating to platelet parameters in patients with autoimmune disorders are limited. The aim of the present study was to investigate, for the first time, the association of platelet parameters with the symptoms of affective disorders in patients with autoimmune conditions. In this cross-sectional study, we measured the complete blood count (CBC), the Generalized Anxiety Disorder Scale for anxiety (GAD-7), and the Beck Depression Inventory for depression (BDI) in 121 patients with autoimmune disorders. Mean platelet volume (MPV) was positively correlated with both anxiety and depression. Platelet distribution width (PDW) was negatively correlated with anxiety and depression. Before adjustment for covariates, logistic regression analysis revealed a significant association of MPV with depression and anxiety. After adjustment for covariates, only depression was associated with MPV. The area under the ROC curve of MPV for GAD-7 determined anxiety and BDI determined depression was 0.63. Our study showed that among the CBC hematological parameters, the MPV might be a useful biomarker of depression and anxiety in patients with autoimmune disorders. Further investigations of platelet parameters in controlled prospective studies are warranted to confirm our preliminary results.
Keywords: anxiety; depression; mean platelet volume; platelet distribution width.