AUTHOR=Gędek Adam , Modrzejewski Szymon , Gędek Marta , Antosik Anna Z. , Mierzejewski Paweł , Dominiak Monika 

TITLE=Neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, and monocyte to lymphocyte ratio in ADHD: a systematic review and meta-analysis

JOURNAL=Frontiers in Psychiatry

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2023.1258868

DOI=10.3389/fpsyt.2023.1258868

ISSN=1664-0640

ABSTRACT=Introduction: Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder with an unclear etiology. Systemic inflammation and immune dysregulation may play a role in the pathogenesis of ADHD. Morphology-derived parameters such as neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and monocyte to lymphocyte ratio (MLR), have been proposed as peripheral biomarkers of the immune-inflammatory process in various diseases., hHowever, studies examining their role in ADHD remain inconclusive.Methods: A systematic review and a meta-analysis wasere conducted to evaluate the association between NLR, MLR, PLR and ADHD. Relevant articles were identified, screened, and assessed for quality according to PRISMA guidelines. Moreover, aA qualitative and quantitative analyseis wasere performed.Result: The review contained eEight eligible studies were included in review, five of which were included in the meta-analysis. The meta-analysis showed that ADHD patients had higher NLR and PLR values compared to health controls. No significant difference in MLR value was observed 2 This is a provisional file, not the final typeset article between the two groupsMLR values did not show a significant difference between the two groups. Analysis in relation to ADHD subtypes showed no significant differences in inflammatory markers in any of the included studies as well. The influence of medical treatment on these ratios could not be adequately assessed due to limited data. Conclusions: ADHD patients exhibit higher NLR and PLR than healthy controls values are higher in ADHD patients, which may indicate the potential immune-inflammatory involvement in this disorder. Further studies on inflammatory markers and ADHD, especially those considering the impact of treatment and clinical symptoms, are essential to comprehensively understand this association.