Markers of systemic inflammation, including raised erythrocyte sedimentation rate (ESR) (OR: 1.62, 95% CI: 1.13–2.32, p = 0.008) and C-reactive protein (CRP) (OR: 1.51, 95% CI: 1.06–2.15, p = 0.021), as well as an elevated neutrophil-to-lymphocyte ratio (NLR) (OR: 1.44, 95% CI: 1.03–2.02, p = 0.033), were associated with OSA severity. Here, CRP is linked to obstructive sleep apnea syndrome.