Clinical characteristics of late-onset adult autoimmune glial fibrillary acidic protein astrocytopathy: a retrospective cohort study

To characterize the distinct clinical phenotype of late‑onset (onset age ≥ 50 years) adult autoimmune glial fibrillary acidic protein astrocytopathy (A‑GFAP‑A).

This single-center retrospective study included 104 adult patients diagnosed with A-GFAP-A, who were stratified into the late-onset group (LOG, n = 31) and the early-onset group (EOG, n = 73). Demographic, clinical, cerebrospinal fluid (CSF), neuroimaging, and short-term outcome data were compared. Multivariable logistic regression and hierarchical cluster analysis were performed.

Compared with EOG, LOG showed a higher prevalence of hypertension (19.4% vs. 2.7%, p = 0.012), a higher proportion of moderately severe disability (modified Rankin Scale [mRS] score = 4) (29.0% vs. 12.3%, p = 0.039), and a lower proportion of severe disability (mRS = 5) (22.6% vs. 45.2%, p = 0.030). Meanwhile, LOG had a lower incidence of bowel/bladder dysfunction (54.8% vs. 76.7%, p = 0.026), a lower rate of elevated CSF opening pressure (25.8% vs. 64.4%, p < 0.001), and less thalamic involvement (16.1% vs. 38.4%, p = 0.026). After adjustment for hypertension, LOG was associated with higher odds of moderately severe disability (mRS = 4), as well as lower odds of elevated CSF opening pressure and thalamic involvement. Symptom clustering analysis revealed a looser and more discrete phenotypic architecture in the LOG. No significant intergroup differences were observed in mRS scores at short-term follow-up.

Late-onset adult A-GFAP-A presents a distinct clinical phenotype. However, there was no significant difference in short-term outcomes between the groups.