Neutrophil-to-lymphocyte ratio is a risk indicator of Guillain-Barré syndrome and is associated with severity and short-term prognosis.

Introduction: Guillain-Barré syndrome (GBS) is an autoimmune disorder targeting the peripheral nervous system. The neutrophil-to-lymphocyte ratio (NLR), a simple indicator of immune function, is potentially related to its incidence and severity; however, this should be confirmed. We aimed to evaluate the role of NLR in the diagnosis, severity, and prognosis of GBS. Methods: Data of GBS patients and controls visiting our hospital from January 2010 to December 2020 were retrospectively analyzed (Clinical trial registration: ChiCTR2100053540). Risk factors were determined through logistic regression. Smoothing curves, receiver-operating characteristic curves, and forest plots were drawn. Results: We included 136 GBS patients and 211 controls. NLR, as a continuous variable, was associated with GBS risk (OR, 2.32; 95% CI, 1.68-3.21; p < 0.001), severe functional disability (OR, 1.23; 95% CI, 1.06-1.43; p = 0.006), severe weakness (OR, 1.19; 95% CI, 1.06-1.35, p = 0.004), and short-term prognosis (OR, 1.21; 95% CI, 1.08-1.36; p = 0.001). NLR was more strongly associated with GBS risk in older (≥60 years) (OR, 7.17; 95% CI, 2.38-21.61) or male (OR, 2.88; 95% CI, 1.78-4.64) patients than in younger (<60 years) (OR, 1.88; 95% CI, 1.37-2.57) or female (OR, 1.85; 95% CI, 1.24-2.77) patients. NLR was significantly associated with severe functional disability in faster disease progression (OR, 1.53; 95% CI, 1.03-12.29) and male patients (OR, 1.41; 95% CI, 1.03-1.92) versus in slower disease progression (OR, 1.12; 95% CI, 0.77-1.64) and female patients (OR, 1.12; 95% CI, 0.77-1.64). Conclusions: NLR may be an independent GBS risk factor and predictor of severe functional disability, severe weakness, and short-term prognosis.