Arzu ŞAHİN BERBEROĞLU, Çağrı ÖĞÜT
Health Sciences Quarterly - 2026;6(4):837-849
This retrospective case-control study examined whether complete blood count-derived inflammatory indices and routine hematological parameters distinguish patients experiencing bipolar depression from healthy controls. Records of 40 patients with bipolar disorder (BD) and 40 controls, aged 18-65 years, were reviewed for April 2023-March 2026. Six inflammatory indices were assessed alongside conventional blood count parameters using group comparisons, correlation analysis, receiver operating characteristic analysis, and exploratory multivariable logistic regression. Monocyte count, monocyte-to-lymphocyte ratio, systemic inflammation response index (SIRI), and pan-immune inflammation value (PIV) were higher in the BD group. Differences were also observed in hemoglobin, hematocrit (HCT), mean corpuscular volume, and red cell distribution width expressed as standard deviation. HCT, SIRI, and PIV showed the highest reported areas under the curve, at 0.678, 0.674, and 0.661, respectively, indicating limited discrimination. Active smoking was substantially more frequent among patients than controls (62.5% versus 12.5%), and the inflammatory indices were strongly intercorrelated. The findings suggest modest group-level hematological differences during bipolar depression; they do not establish diagnostic biomarkers or support routine diagnostic use. The small sample, potential confounding by smoking and medication, and absence of external validation restrict interpretation. Larger prospective studies with appropriate confounder adjustment and independent validation are required.
