Gene Polymorphisms of Interleukin-27 Correlate with the Susceptibility, Severity, and Clinical Outcomes of Elderly People with Guillain-Barré Syndrome

<b><i>Introduction:</i></b> Guillain-Barré syndrome (GBS) is a common autoimmune disease in the peripheral nervous system. This study aimed to elucidate the role of IL-27 gene polymorphisms in elderly people with GBS. <b><i>Methods:</i></b> A total of 395 healthy subjects and 422 GBS patients with an average age of 63 years old were included in this study. Peripheral blood samples were collected. The 2 single-nucleotide polymorphisms (SNPs) of IL-27, namely, rs153109 and rs785575, of GBS patients were analyzed using the PCR method and compared with those of the healthy controls. The correlations of IL-27 SNPs with disease severity, disease outcome, level of anti-GM1 antibodies, and <i>Campylobacter jejuni</i> infection were assessed. Serum levels of IL-27 of healthy subjects and GBS patients were analyzed using enzyme-linked immunosorbent assay. <b><i>Results:</i></b> No significant differences in the frequencies of rs785575 SNPs between GBS and healthy subjects were observed. In analyzing rs153109 SNPs, the G allele was found to be more prevalent in the GBS patients (<i>p</i> = 0.012). More alleles show GG genotype in GBS patients (<i>p</i> = 0.023). The −964A&#x3e;G allele has a higher prevalence in severely affected and anti-GM1-Ab-positive GBS patients. GBS patients with the rs153109 SNP showed a poor clinical outcome than those without rs153109 SNP (<i>p</i> = 0.012). GBS patients showed higher serum IL-27 levels than healthy subjects (<i>p</i> &#x3c; 0.001). The levels of IL-27 were also higher in GBS patients with genotypes of AG and GG, and those with GG genotypes showed the highest IL-27 levels. <b><i>Conclusion:</i></b> The rs153109 SNP is more prevalent in GBS patients with the GG and G allele and is associated with severer GBS, poorer clinical outcomes, and higher IL-27 levels.