Memory performance in Charcot–Marie–Tooth disease patients

Charcot–Marie–Tooth (CMT) disease is characterized by a chronic both motor and sensory polyneuropathy. This is the most common inherited disease of the peripheral nervous system, CMT1A is the most common CMT type, followed by CMTX1 and other subtypes. CMTX1 patients may exhibit CNS involvement during the disease course. There are controversial data about evidence of increased cognitive impairment prevalence and decreased volume of white matter in patients with hereditary neuropathy. The goal of the study was to determine and compare memory impairment in patients with different CMT types and evaluate possible associations with disease severity. We recruited 21 CMT patients from geneticists’, neurologists’ and paediatric neurologists’ clinical practices. Patients responded to an sociodemographic questionnaire and clinical severity was assesed using CMT Neuropathy Score version 2 (CMTNSv2). Assessment of memory cognitive abilities was performed using a computerized neuropsychological test battery, CNS Vital Signs (CNSVS), which provides age-adjusted standard scores for verbal memory (i.e. recognition memory for words) and visual memory (i.e. recognition memory for designs). Data from 21 CMT patients were analysed, from our group 42.9% (n=9) were CMT1A patients, 23.8% (n=5) were CMTX1 patients and 33.3% (n=7) other subtype CMT. Mean age in study group 37.3 ± 12.5 years. Clinical assesment revealed mean CMTNSv2 14.1 ± 8.0, in CMT1A it was 14.2 ± 3.8, in CMTX1 21.2 ± 7.6 and in other CMT type 9.0 ± 9.1. All study group patients took CNSVS memory tests. Analyses showed no abnormalities on CNSVS memory domain scores in verbal and visual memory. All patients had mean scores that were within the average range, without differences in subgroups. CMT patients did not have memory impairments assesed by CNSVS according to our study results, these findings was regardless of CMT subtype. Further research with larger patient cohorts are needed.