Correlation between elevated blood and cerebrospinal fluid glucose levels and the severity and short-term prognosis of Guillain–Barré syndrome

Objective: This study aimed to explore the relationships between diabetes mellitus and Guillain–Barré syndrome (GBS) progression and short-term prognosis. Materials and methods: This retrospective cohort analysis included 330 patients with GBS. The study was performed at the Department of Neurology, Kasturba Medical College, Manipal, from January 2016 to December 2023. Diabetes mellitus was present in 31.8% of the 330 GBS patients. The degree of disability was assessed according to the GBS Disability Scale (GDS). Results: Compared with patients with normal glycosylated hemoglobin A1c (HbA1c) and cerebrospinal fluid (CSF) glucose levels, patients in the high HbA1c and high CSF glucose groups were characterized by severe disability (GDS ≥ 3) at admission (52.4 vs. 75.2, P = 0.001; 80 vs. 53.4, P = 0.001), at nadir (63.1 vs. 83.8, P = 0.02; 84.5 vs. 60.6, P = 0.03), and at discharge (52.4 vs. 31.1, P = 0.04; 57.8 vs. 27.8, P = 0.03). Older age, gastrointestinal tract infection, and axonal subtype were significantly associated with severe disability at admission, at nadir, and at discharge. Elevated blood levels of HbA1c were significantly correlated with worse disability at admission (OR = 0.64) and at nadir (OR = 0.74) but not at discharge. Elevated CSF glucose levels were significantly correlated with severe disability at admission (OR = 0.68), at nadir (OR = 0.62), and at discharge (OR = 0.72). Conclusion: The present study revealed that elevated glucose levels in the blood and CSF were correlated with disease severity at admission, nadir and discharge and might predict the short-term prognosis of GBS patients.