New Hematological Parameters as Inflammatory Biomarkers: Systemic Immune Inflammation Index, Platerethritis, and Platelet Distribution Width in Patients with Adult Attention Deficit Hyperactivity Disorder

OBJECTIVES: The potential role of neuroinflammation in adult attention deficit hyperactivity disorder (ADHD) patients has been investigated with peripheral hemogram-related inflammatory markers. Systemic immune inflammation index (SII) is defined as a new index that has been developed for the balance of inflammatory and immune status. METHODS: Our study was based on a prospective routine complete blood count(CBC) analysis of 74 Adult ADHD patients and 70 healthy participants. The DSM-5-Clinician version and Barratt impulsivity scale-11 were used to evaluate the participants. RESULTS: There was no statistical difference in the comparison of the SII ratios, platelet distribution width (PDW), and plateretritis (PCT) (p>0.05 for each) in a group of a young adults with ADHD and in a comparison control group. These inflammatory indicators were found to be similar between patients newly diagnosed with ADHD (n=40) and patients using methylphenidate (n=34) (p>0.05 for each). The relationship between ADHD clinical symptoms and severity and inflammation was evaluated. A significant negative correlation was observed between attention deficit scores and PCT (r=−0.301, p=0.009). A positive significant correlation was found between hyperactivity scores and SII (r=0.247, p=0.034). A significant positive correlation was found between Barrat motor scores and PDW(r=241, p=0.038). In the regression analysis, the PCT variable changed the attention deficit variable (β=.33, t(70)= −2.703, p=.009, pr(2)= .094) predicted negatively and significantly. CONCLUSIONS: We demonstrated the association of SII, which is independently associated with adverse outcomes in many diseases, and the severity of hyperactivity symptoms in adult ADHD. The fact that PCT predicts attention deficit negatively and decisively shows the importance of inflammatory assessments specific to clinical presentations. The critical importance of platelets in inflammatory processes in ADHD has been demonstrated once again with inflammatory markers such as SII, PLT, and PDW, which can be accessed by an easily applicable complete blood count method.