Objectives: To determine the value of the whole-blood inflammatory response index as an emerging biomarker for the assessment of disease activity in osteoarthritis (OA).
Methods: Extensive analysis of the literature on OA and whole-blood inflammatory indicators were provided through a bibliometric approach. Clinical characteristics and indicators of OA patients and healthy controls (HC) were retrospectively analysed. Four whole-blood inflammatory response indices - neutrophil/lymphocyte count (NLR), platelet/lymphocyte count (PLR), monocyte/lymphocyte count (MLR), and systemic inflammation response index (SIRI), as well as clinical traits like the OA patient's self-perception and immune-inflammatory indicators were analysed for correlations. Cut-off values were determined using receiver operating characteristic (ROC) curves, and they were subsequently employed in logistic regression models to work out whole-blood inflammatory indices and disease activity.
Results: The pathophysiology of osteoarthritis has received most of the spotlight in literature studies of OA and whole-blood inflammation indicators. The "inflammation", "osteoarthritis" and "disease activity" were the top 3 key word clusters. Retrospective analysis showed that MLR, NLR, PLR, and SIRI were markedly higher in OA subjects compared to HC subjects. ROC curve consequences manifested that SIRI and NLR could separate OA from healthy controls. NLR, PLR, MLR, and SIRI proved to be related to immune-inflammatory markers, visual analogue scale (VAS) scores, and short-form (SF)-36 scores with regard to correlation analysis and association criteria. Logistic regression manifested that SIRI, NLR, and C-reactive protein (CRP) forecasted disease activity, however, the model that combined SIRI and CRP was superior to CRP alone.
Conclusions: SIRI may serve as a non-invasive, appropriate biomarker to correlate with disease activity.