Socioeconomic and Racial Disparities in Guillain-Barré Syndrome

ABSTRACT

Objectives: Guillain-Barré syndrome (GBS) is a rapidly progressive neuromuscular disorder that often requires intensive care and immunomodulatory therapy. Despite standardized treatment approaches, access to care and outcomes may be influenced by social determinants of health. We evaluated associations between socioeconomic and racial factors and inpatient interventions and outcomes in GBS in the US.
Study Design: Retrospective cohort study.
Methods: This retrospective cohort study used data from the National Inpatient Sample (2016-2021) to identify hospitalizations with a primary diagnosis of GBS (International Statistical Classification of Diseases, Tenth Revision code G61.0). Multivariable logistic regression models assessed associations between demographic and socioeconomic variables and 5 prespecified outcomes: in-hospital mortality, nonroutine discharge, prolonged hospitalization, receipt of intravenous immunoglobulin (IVIG), and receipt of plasmapheresis.
Results: We analyzed 45,515 GBS-related hospitalizations (patients’ mean age, 50.7 years; 46.0% female). After adjusting for covariates, higher zip code income was associated with reduced inpatient mortality (OR per quartile, 0.80; 95% CI, 0.66-0.98). Admission to private investor–owned hospitals was associated with lower IVIG or plasmapheresis use, an effect not seen when analyzing only privately insured patients. Black patients were less likely to receive plasmapheresis (OR, 0.75; 95% CI, 0.59-0.95). Black and Native American patients had higher odds of nonroutine discharge (Black: OR, 1.26; 95% CI, 1.06-1.51; Native American: OR, 2.16; 95% CI, 1.20-3.88). Medicare coverage was associated with higher odds of nonroutine discharge (OR, 1.90; 95% CI, 1.62-2.23), and Medicaid coverage was associated with prolonged hospitalization (OR, 1.73; 95% CI, 1.48-2.02). Self-pay was linked to reduced odds of nonroutine discharge but longer hospitalization (OR, 0.53; 95% CI, 0.43-0.66).
Conclusions: This study reveals socioeconomic, racial, and institutional disparities in GBS hospitalization outcomes despite standardized treatment guidelines. These findings highlight the need for equity-focused strategies to ensure timely and consistent care for patients with acute neurologic conditions.

Am J Manag Care. 2026;32(Spec. No. 6):In Press

Guillain-Barré syndrome (GBS) is an acute, immune-mediated polyradiculoneuropathy characterized by progressive weakness, areflexia, and potentially life-threatening respiratory involvement. Although its incidence varies by age, geography, and preceding infections, management with intravenous immunoglobulin (IVIG) or plasmapheresis has largely standardized treatment pathways in high-resource settings.¹ However, outcome variability still persists, particularly in relation to nonclinical factors.^{2, 3}

Disparities in neurologic care are increasingly recognized as manifestations of organizational inequity rather than differences in underlying disease biology.^4-7 Prior studies in stroke,^8-11 epilepsy,^12-14 and multiple sclerosis^15,16 have shown that race, insurance status, and income level can meaningfully shape both access to care and hospital-based outcomes in acute neurological conditions. However, studies assessing whether these factors can affect outcomes in GBS remain lacking, despite evidence that treatment timing influences outcomes in GBS.¹⁷

To address this knowledge gap, we used a nationally representative sample of 45,515 hospitalizations for GBS between 2016 and 2021 to examine the associations among socioeconomic and racial factors and 5 prespecified outcomes: in-hospital mortality, nonroutine discharge, prolonged hospitalization, receipt of IVIG, or receipt of plasmapheresis.

METHODS

Data Source and Cohort Definition

We performed a retrospective cohort study using the National Inpatient Sample (NIS) data sets from 2016 to 2021, which are part of the Healthcare Cost and Utilization Project (HCUP).¹⁸ The NIS contains a representative sample of inpatient admissions to hospitals in the US, constituting approximately 7 million hospital admissions annually. Through the application of sampling weights, the NIS can be used to generate estimates for approximately 35 million annual admissions.¹⁹ The NIS is a publicly available database, and data are fully deidentified; therefore, ethical approval was not required. This study conforms to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines.²⁰ The analyses presented in this article adhere to the HCUP data use agreement, which prohibits the sharing of the data used for these analyses.

Using International Statistical Classification of Diseases, Tenth Revision (ICD-10) codes, cases were included if they had a primary diagnosis of GBS (code G61.0). Elective admissions were excluded from analysis. We extracted the following variables from the database: age, sex, race (White, Black, Hispanic, Asian or Pacific Islander, Native American, other), primary payer (Medicare, Medicaid, private insurance, self-pay, no charge, other), smoking status, Elixhauser comorbidities, hospital size (bed count), hospital teaching status (rural, urban nonteaching, urban teaching), hospital ownership (government nonfederal, private nonprofit, private investor–owned), hospital’s census region (Northeast, Midwest or North Central, South, West), rurality (increasing rurality from 1-6), and patients’ quartile of average estimated zip code income. The elixhauser Stata package was used to calculate Elixhauser comorbidities.²¹ Elixhauser comorbidities were as follows: congestive heart failure, cardiac arrhythmias, valvular disease, pulmonary circulation disorders, peripheral vascular disorders, uncomplicated hypertension, complicated hypertension, paralysis, other neurological disorders, chronic pulmonary disease, uncomplicated diabetes, complicated diabetes, hypothyroidism, renal failure, liver disease, peptic ulcer disease excluding bleeding, AIDS/HIV, lymphoma, metastatic cancer, solid tumor without metastasis, rheumatoid arthritis/collagen vascular diseases, coagulopathy, obesity, weight loss, fluid and electrolyte disorders, blood loss anemia, deficiency anemia, alcohol abuse, drug abuse, psychoses, and depression, using ICD-10 codes as previously described.²²

We focused analyses on key demographic and socioeconomic variables that have been shown to be predictive of outcomes in other neurological disorders.²³ These were income, race, insurance status, and hospital ownership.^24-27

Outcomes

We analyzed 5 outcomes: inpatient mortality, nonroutine discharge (defined as any discharge other than routine home discharge, including inpatient mortality, transfer to another hospital or other care facility [eg, skilled nursing facility], or home health care), prolonged length of stay (defined dichotomously as having an admission duration of ≥ 14 days²⁸), receipt of IVIG (defined as patients receiving ICD-10 Procedure Coding System [PCS] codes of XW133D7, 30233S0, and/or 30233S1 during admission) and receipt of plasmapheresis (defined as patients receiving ICD-10 PCS codes of 6A550Z3 and/or 6A551Z3 during admission).

Statistical Analyses

Statistical analyses were performed using Stata 18.0/MP (StataCorp LLC). Multivariable logistic regression models were built to study the effects of socioeconomic variables on inpatient mortality, nonroutine discharge, length of stay, and odds of receiving IVIG or plasmapheresis. All models adjusted for age, sex, race, primary payer, smoking status, number of Elixhauser comorbidities, hospital size, hospital teaching status, hospital ownership, hospital’s census region, hospital rurality, and patients’ average estimated zip code income. Variables were selected a prioribased on established clinical significance and prior literature^19,29,30 and were forced into all models to generate fully adjusted models to minimize confounding; no stepwise variable selection was performed. Missing data were handled on a complete case analysis basis, as missingness was less than 5% for all variables³¹ (Figure). For potential continuous variables (age, number of Elixhauser comorbidities, and zip code income), we assessed whether the log odds of each outcome had alinear relationship with each continuous predictor using the Box-Tidwell test; a P value of less than .05 indicated significant nonlinearity. We found significant nonlinearity for age and number of Elixhauser comorbidities; accordingly, these variables were analyzed categorically as follows: Age was dichotomized at 60 years of age (< 60 and ≥ 60 years), and the number of Elixhauser comorbidities was divided into 3 levels of 0, 1 to 4, and more than 4 comorbidities.²³ Zip code income quartile was analyzed as a continuous ordinal variable in logistic regression models. ORs were reported alongside 95% CIs. A significance threshold of P less than .05 was used to define statistical significance throughout.

RESULTS

Cohort Characteristics

A total cohort of 45,515 inpatient admissions was included, following exclusions for missing data and application of sampling weights (Figure). Cohort characteristics are summarized in the Table.

The mean (SD) age of the cohort was 50.7 (20.0) years; the proportion of female patients was 46.0%. Of included patients, the most common race was White (70.6%), followed by Hispanic (12.5%) and Black (9.4%). A plurality of patients had a primary expected payer of private insurance (44.5%), followed by Medicare (29.4%) and Medicaid (17.7%). The most common Elixhauser comorbidities were uncomplicated hypertension (44.2%) and fluid and electrolyte disorders (38.7%). Of patients, 25.8% and 13.0% received IVIG and plasmapheresis, respectively, after application of sampling weights. Of included patients, 1.5% died during admission, 66.1% had nonroutine discharge, and 21.1% had a prolonged length of stay.

Inpatient Mortality

After adjusting for confounders, patients with Medicare insurance had significantly increased odds of inpatient mortality (OR, 2.66; 95% CI, 1.54-4.59; P < .001). Patients with an unspecified source of insurance also had increased odds of inpatient mortality (OR, 2.66; 95% CI, 1.05-8.70; P = .040). Additionally, increased zip code income quartile was associated with decreased odds of inpatient mortality, with each increasing quartile of income being associated with a 20% reduction in odds of inpatient mortality (OR, 0.80; 95% CI, 0.66-0.98; P = .027).

Nonroutine Discharge

After adjusting for confounders, Black patients (OR, 1.26; 95% CI, 1.06-1.51; P = .010) and Native American patients (OR, 2.16; 95% CI, 1.20-3.88; P = .010) both had increased odds of nonroutine discharge. Regarding insurance status, patients with a primary expected payer of Medicare had increased odds of nonroutine discharge (OR, 1.90; 95% CI, 1.62-2.23; P < .001). In contrast, self-pay patients had decreased odds of nonroutine discharge (OR, 0.53; 95% CI, 0.43-0.66; P < .001).

Prolonged Length of Stay

Patients admitted to private nonprofit hospitals were more likely to have a prolonged length of stay relative to the reference category of public hospitals (OR, 1.31; 95% CI, 1.11-1.55; P = .002). Regarding insurance status, both patients with a primary expected payer of Medicaid (OR, 1.73; 95% CI, 1.48-2.02; P < .001) and self-paying patients (OR, 1.47; 95% CI, 1.14-1.90; P = .003) had increased odds of prolonged length of stay.

Interventions

Patients admitted to private investor–owned hospitals were less likely to receive IVIG than those admitted to public hospitals (OR, 0.35; 95% CI, 0.28-0.44; P < .001). Patients admitted to private nonprofit hospitals were not less likely to receive IVIG (OR, 0.96; 95% CI, 0.82-1.13; P = .632). Additionally, increased zip code income quartile was associated with increased odds of receiving IVIG, with each increasing quartile of income being associated with a 6% increase in the odds of receiving IVIG (OR, 1.06; 95% CI, 1.00-1.11; P = .038).

Black patients were 25% less likely to receive plasmapheresis after adjusting for confounders (OR, 0.75; 95% CI, 0.59-0.95; P = .016). Patients admitted to private investor–owned hospitals were less likely to receive plasmapheresis than those admitted to public hospitals (OR, 0.77; 95% CI, 0.60-0.99; P = .038). Notably, when subanalyzing only those patients whose primary expected payer was private insurance, this association disappeared (OR, 0.74; 95% CI, 0.50-1.09; P = .128). Patients admitted to private nonprofit hospitals were not less likely to receive plasmapheresis (OR, 1.00; 95% CI, 0.80-1.25; P = .991).

DISCUSSION

In this nationally representative cohort of more than 45,000 hospitalizations for GBS, we identified significant associations of socioeconomic status (SES), race, insurance coverage, and hospital ownership with multiple inpatient outcomes. Higher neighborhood income and institutional characteristics were associated with differences in mortality risk and immunotherapy use, whereas racial and insurance-based differences were observed in treatment receipt and discharge outcomes. Together, these findings indicate that inpatient outcomes in GBS vary systematically across socioeconomic, racial, insurance, and institutional contexts, even after adjustment for clinical and hospital characteristics.

The overall immunotherapy rates observed in our cohort (25.8% for IVIG, 13.0% for plasmapheresis) were lower than those reported in prospective clinical studies. For example, the International GBS Outcome Study reported in 2019 that 92% of patients received immunotherapy, with rates approaching 97% in those with severe disease and 75% in those with mild disease.² A single-center European study, with results published in 2021, similarly found that 99% of patients received treatment, which the authors attributed to tertiary care center bias.³² However, our findings are consistent with other NIS-based analyses; Beydoun et al reported that only 16.8% of GBS hospitalizations in the NIS from 2002 to 2014 had documented immunotherapy codes.²⁹ This discrepancy likely reflects several factors: The NIS captures all hospitalizations, including mild disease that may not meet treatment thresholds, procedural coding for IVIG may be incomplete when bundled into general infusion codes, and prospective clinical cohorts overrepresent referral centers with established treatment protocols. Despite these limitations, the consistent socioeconomic and racial gradients in treatment receipt suggest that differences in care delivery persist beyond what can be explained by coding variability or severity-based decision-making alone.

Higher income was independently associated with both a 20% reduction in the odds of inpatient mortality and increased odds of receiving IVIG. This finding supports prior research indicating that neighborhood-level SES is a powerful determinant of health outcomes across a range of neurologic disorders, including stroke and degenerative nervous system disorders.^33,34 Income quartile likely reflects not only individual patient resources but also access to well-resourced hospitals, earlier recognition of symptoms, shorter delays in diagnosis or referral, and potentially more consistent adherence to standardized treatment protocols, as emerging neurologic frameworks increasingly emphasize longitudinal disease vulnerability.^35-37 Our findings underscore the need for targeted public health interventions to support GBS care in lower-income communities.

Our findings regarding hospital ownership are also concerning. Patients admitted to private investor–owned hospitals were less likely to receive either IVIG or plasmapheresis than those in public hospitals. However, this association with plasmapheresis disappeared in patients with private insurance, suggesting that institutional treatment decisions may be influenced by payer mix or profit motive. Conversely, nonprofit hospitals were associated with increased odds of prolonged length of stay, potentially reflecting more comprehensive but slower-paced care or logistical barriers to discharge. These findings are particularly pressing given the recent increase in private equity hospital ownership in the US.^38,39 Together, these findings raise important questions about the role of hospital ownership in delivering equitable care for high-cost, guideline-driven conditions such as GBS.

Race was significantly associated with several key outcomes. Black and Native American patients had increased odds of nonroutine discharge, and Black patients were less likely to receive plasmapheresis. Similar disparities have been noted in those with stroke^10,40-45 or epilepsy,^12,46,47 where inequities and differential access to postacute care facilities contribute to unequal treatment trajectories. The underutilization of plasmapheresis in Black patients is particularly concerning, even though IVIG is more commonly administered due to its ease of use and lower procedural risk; both are considered first-line therapies and equally effective in GBS management. Although this disparity may reflect broader systemic inequities, including implicit bias, it also highlights the importance of standardized treatment protocols to reduce inconsistent clinical decision-making.

Insurance status was a consistent predictor of poor outcomes. Patients with Medicare had significantly higher odds of nonroutine discharge, and those with Medicaid or no insurance experienced significantly longer hospitalizations. Interestingly, self-pay patients had lower odds of nonroutine discharge, potentially reflecting barriers to postacute placement or differences in financial incentives that disfavor discharge to facilities. These findings point to systemic inefficiencies in care coordination for publicly insured or underinsured populations.

The racial and socioeconomic disparities we observed likely reflect structural barriers that shape access to neurologic care. The proportion of White patients in our cohort (70.6%) was higher than in the US general population (approximately 60%-62% non-Hispanic White),⁴⁸ which may reflect differential access to hospital-based care rather than true differences in GBS incidence. Although early surveillance data suggested possible variation in GBS incidence by race, international reviews have found no clear racial preponderance, supporting the interpretation that observed differences are more likely driven by health care access rather than true incidence variation.^49,50 If racial and ethnic minority group patients experience barriers such as lack of insurance, transportation limitations, or medical mistrust, they may be less likely to reach hospital systems captured in administrative data sets, potentially leading to underestimation of the true magnitude of inequities in GBS care.^51,52 Prior work shows that underserved communities often have reduced access to neurologists,^53,54 specialized neurologic care,^54-56 and high-quality hospital services.^10,57 Socioeconomic disadvantage and racial inequities have also been associated with delayed diagnosis across several neurological disorders,^58,59 which may contribute to neurological deterioration and worse hospitalization outcomes.^60,61 In GBS specifically, timely initiation of immunotherapy is critical for optimizing recovery, and barriers to specialty care or facilities equipped to administer IVIG or perform plasmapheresis may disproportionately affect patients from lower-income and minoritized communities.^62,63 In addition, patients from racial and ethnic minority groups and lower-income neighborhoods are more likely to receive care in underresourced hospitals.⁶⁴ Hospital resource distribution, including differences in neurologic care capacity and institutional financial constraints, may influence treatment decisions, particularly for high-cost interventions such as immunotherapy.^65,66 Insurance status can further limit access to guideline-recommended treatments and contribute to the disparities observed in our cohort.^67,68 Together, these system-level inequities may explain, in part, why Black patients, those with Medicaid, and those from lower-income areas were less likely to receive immunotherapy and experienced worse discharge outcomes.

Our results have several practical implications for clinicians and health systems caring for patients with GBS. Clinicians should ensure timely neurologic evaluation and early initiation of IVIG or plasmapheresis for patients from lower-income neighborhoods and those covered by Medicare or Medicaid, who, in our cohort, experienced higher mortality, more frequent nonroutine discharge, and prolonged hospitalizations. For these groups in particular, prompt treatment initiation may help mitigate the risks associated with structural disadvantage. Given the lower use of plasmapheresis among Black patients and at investor-owned hospitals, institutions could implement standardized, guideline-based protocols for selecting between IVIG and plasmapheresis, with explicit monitoring for disparities by race, insurance status, and hospital ownership. At the point of discharge, targeted care coordination for socioeconomically disadvantaged and publicly insured patients, such as proactive rehabilitation referrals, case management, and structured pathways for outpatient neurology follow-up, may help reduce disparities in nonroutine discharge and promote more equitable functional recovery.

Limitations

Our findings should be interpreted in the context of several limitations. First, any observational study inherently has the potential for residual confounding. Although we adjusted for a wide panel of covariates in multivariable analyses, the NIS is an administrative database. It therefore lacks granular clinical details such as GBS subtype, disease severity at admission (eg, Medical Research Council or Hughes scores), or timing of presentation relative to symptom onset. Accordingly, unobserved factors may be confounding the observed associations. This limitation is particularly relevant because patients with higher income or more comprehensive insurance coverage may present earlier in the disease course, when neurological impairment is less severe. As a result, associations between socioeconomic factors and outcomes may be partially confounded by disease severity at presentation. Additionally, the NIS’ administrative nature, reliant on hospital-level reporting, means that differences in regional coding practices, particularly regarding race misclassification, may bias this study’s findings. It is also worth noting that causality cannot be inferred from observational data. Our study period encompassed the COVID-19 pandemic, which may have influenced health care–seeking behavior. Emergency department visits in the US declined by approximately 42% during the early pandemic, with patients delaying care due to fear of COVID-19 exposure, an effect disproportionately observed among racial and ethnic minority groups and those with lower SES.^69,70 The lower proportion of admissions in our cohort during 2020 may reflect such reduced health care seeking. However, sensitivity analyses adjusting for year of admission demonstrated that the magnitude of reported associations remained essentially unchanged, suggesting that pandemic-related factors did not substantially confound our findings. Finally, our use of zip code–level income as a proxy for individual SES may obscure within-area variability. In addition, the generalizability to non-US populations should be interpreted with caution, especially for countries with universal health care systems.

CONCLUSIONS

Clinical guidelines for GBS emphasize timely access to immunomodulatory therapy. However, our results underline persistent inequities shaped by race, insurance status, income level, and hospital type. These disparities likely reflect broader structural barriers within the health care system and underscore the need for equity-driven solutions, including improved insurance access, equity-focused hospital performance metrics, and guideline implementation strategies that explicitly account for social determinants of health. Future studies should examine the underlying drivers of treatment disparities in GBS (particularly among Black patients and those treated at investor-owned hospitals) and incorporate qualitative assessments of provider decision-making and institutional protocols. Longitudinal studies linking inpatient care to postdischarge outcomes will be essential to determine the lasting impact of these disparities and to identify effective intervention targets.

Acknowledgments

Yagiz M. Altun, MD, PhD, and Edward R. Bader, MBChB, MS, contributed equally to this work and are listed as co–first authors.

Author Affiliations: Department of Neurology (YMA, SY, LG) and Department of Neurological Surgery (ERB), Albert Einstein College of Medicine, Bronx, NY.

Source of Funding: Dr Bader was supported in part by the Einstein-Montefiore Clinical and Translational Science Award Hub (1UM1TR004400; MPI: Keller, Kim) and the Predoctoral T32 at Albert Einstein College of Medicine (T32TR004537; MPI: Marantz, Hosgood).

Author Disclosures: The authors report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design (YMA, ERB, SY); acquisition of data (ERB, SY); analysis and interpretation of data (YMA, ERB); drafting of the manuscript (YMA, ERB); critical revision of the manuscript for important intellectual content (YMA, ERB, SY, LG); statistical analysis (ERB); provision of study materials or patients (ERB); obtaining funding (ERB); administrative, technical, or logistic support (YMA, LG); and supervision (YMA, LG).

Send Correspondence to: Yagiz M. Altun, MD, PhD, Albert Einstein College of Medicine, 1300 Morris Park Ave #401K, Bronx, NY 10461. Email: yagiz.altun@einsteinmed.edu.

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