Autonomic Nervous System Phenotyping Across Chronic Demyelinating Peripheral Neuropathies: A Comparative Study.

BACKGROUND AND AIMS: This study aimed to systematically phenotype autonomic nervous system (ANS) involvement in patients with chronic inflammatory demyelinating polyneuropathy (CIDP), monoclonal gammopathy of undetermined significance-associated neuropathy (MGUS-PNP), Charcot-Marie-Tooth disease Type 1A (CMT1A), and hereditary neuropathy with liability to pressure palsies (HNPP).

METHODS

Autonomic symptoms were assessed using the SCales for Outcomes in Parkinson's Disease-Autonomic Dysfunction (SCOPA-AUT). Muscle strength and functional disability were evaluated using the Medical Research Council (MRC) scale, the Inflammatory Neuropathy Cause and Treatment (INCAT) disability scale, and the Overall Neuropathy Limitation Scale (ONLS).

RESULTS

A total of 343 participants were included: 98 with CIDP (mean age: 59.2 ± 13.2 years), 51 with MGUS-PNP (66.0 ± 11.3 years), 51 with CMT1A (51.2 ± 13.1 years), 18 with HNPP (40.6 ± 15.1 years), and 125 healthy controls (58.2 ± 13.3 years). Compared with healthy controls, patients with CIDP, MGUS-PNP, and CMT1A showed significantly higher total SCOPA-AUT scores (p < 0.01). Distinct, disease-specific ANS symptom patterns were observed across neuropathy subtypes. Overall disability was independently associated with overall autonomic symptom burden in MGUS-PNP (β = 0.42, p < 0.05) and CMT1A (β = 0.68, p < 0.05). In CIDP, patients with active disease showed higher autonomic symptom burden than those with inactive disease (12.7 ± 11.7 vs. 8.6 ± 7.9, p = 0.042).

INTERPRETATION: Patients with CIDP, MGUS-PNP, and CMT1A exhibit a substantial autonomic symptom burden with distinct disease-specific ANS patterns. These findings highlight the relevance of autonomic dysfunction in immune-mediated and hereditary neuropathies and warrant further studies to clarify their clinical and prognostic significance.