Investigation of Demographic, Clinical, Management and Outcome Characteristics Among Iranian Patients with GBS Following COVID Infection

COVID-19 has been recognized as a severe respiratory disease pandemic (1). Studies have reported variability in the age and sex of patients affected by COVID-19 worldwide (2-4). COVID-19 not only involved the respiratory system but also caused complications in other organs, including the cardiovascular, hematological, psychological, cutaneous, and nervous systems (5). The coronavirus can invade the central nervous system (CNS) and cause neurological pathologies under certain conditions (6). This disease has been associated with neurological complications in the CNS such as encephalopathy, encephalitis, acute myelitis, cerebrovascular disorders, headache, dizziness, stroke, and epileptic seizures. In addition, several types of peripheral nervous system (PNS) disorders, including cranial nerve involvement (e.g., vestibulocochlear neuropathy, olfactory neuropathy), skeletal muscle injury, and Guillain-Barré syndrome (GBS), have been reported as complications of COVID-19 (7, 8).

Guillain-Barré syndrome is the most common cause of acute or subacute generalized weakness, affecting between 0.8 and 1.9 cases per 100,000 people annually in Europe and North America (9). It is commonly characterized by weakness and areflexia and is treated with plasmapheresis and intravenous immunoglobulin (IVIG) (10, 11). The incidence rate of the syndrome in Iran is reported to be between 2 and 11 cases per 100,000 people (12). Several studies have reported a close relationship between GBS and COVID-19 (13-15), and it accounts for 84.2% of the PNS complications associated with COVID-19 in Iran (9). This syndrome has been more commonly observed in males and elderly individuals. Acute motor and sensory axonal neuropathy (AMSAN) and acute motor axonal neuropathy (AMAN) represent the dominant patterns of nerve involvement. Lower limb weakness, facial weakness, and paresthesia were the core clinical presentations in China, Iran, Europe, and the USA (12).

While several case studies (12-17) have evaluated the association between COVID-19 and GBS, no retrospective study with a large population size has been conducted to date. Therefore, this study was conducted to investigate the clinical characteristics of GBS in patients with and without COVID-19.

The COVID-19 PCR test result status among the 50 COVID-19 patients showed that 11 patients (7.70%) tested positive, 27 patients (18.90%) tested negative, and 12 patients (8.90%) had unknown results. Half of the patients (n = 25, 50.00%) exhibited symptoms of COVID-19 infection, while the remaining half (n = 25, 50.00%) were asymptomatic. A total of 26 patients (18.20%) demonstrated typical changes of COVID-19 infection on chest CT scans, 16 patients (11.20%) had negative chest CT scans, and 8 patients (5.60%) did not undergo chest CT imaging (Table 1).

Our findings revealed that, apart from the difference in age (P = 0.001), most clinical features, treatment outcomes, and electrodiagnostic patterns were similar between the two groups. This aligns with previous studies, such as those by Palaiodimou et al. (18) and Abu-Rumeileh et al. (15), which reported that older individuals are more susceptible to COVID-19-associated neurological complications, including GBS. The higher age observed in COVID-19 patients could be attributed to the virus's known impact on older adults due to factors such as immunosenescence and the increased prevalence of comorbidities.

Despite this age difference, no significant variation was observed in gender distribution, consistent with studies by Caress et al. (19) and Aladawi et al. (20), which found no strong gender predisposition for GBS associated with COVID-19. Although some reports suggest a male predominance in both COVID-related and classic GBS cases, our findings did not reflect this trend significantly.

In terms of clinical presentation, progressive limb weakness remained the most common symptom in both groups, which is typical for GBS. Interestingly, paresthesia was significantly more prevalent in non-COVID-19 patients (P = 0.001). This contrasts with studies such as Shamim et al. (21), where sensory symptoms were reported equally in both groups. The subjective nature of paresthesia and potential biases in patient history documentation might explain this discrepancy.

Regarding electrodiagnostic findings, the predominance of axonal involvement in the COVID-19 group compared to demyelinating patterns in the non-COVID-19 group was notable but not statistically significant. This trend is partially supported by studies from regions like South Asia, where axonal variants (AMAN and AMSAN) are more common [Bano et al. (22); Yadav et al. (23)]. However, Filosto et al. (24) reported a higher prevalence of demyelinating forms in European COVID-related GBS cases. These variations could be influenced by geographical, genetic, and methodological factors, including the timing of EMG-NCS testing.

Treatment outcomes showed no significant differences between the groups, with most patients receiving IVIG and demonstrating partial or complete recovery. This finding aligns with prior studies [Caress et al. (19); Martinelli-Boneschi et al. (25)], suggesting that standard GBS treatments remain effective regardless of COVID-19 status. However, the mortality rate was slightly higher in COVID-19 patients (22% vs. 7.5%), though not statistically significant. Some studies, such as Bentley et al. (26), have reported higher ICU admissions and ventilation needs in COVID-19-associated GBS, but our data did not reflect these differences, possibly due to sample size limitations or variations in healthcare resources.

Another important observation was the interval between COVID-19 infection and GBS onset, averaging around 17.92 ± 15.11 days. This finding aligns with the typical post-infectious latency period reported in the literature [Sriwastava et al. (27)], supporting the hypothesis that immune-mediated mechanisms play a role in COVID-19-associated GBS.