Cognitive impairment as a central cholinergic deficit in patients with Myasthenia Gravis

AbstractBackgroundThe purpose of this study was to investigate with neurophysiological and neuropsychological methods such as pupillometry, cognitive test and Hamilton Depression Rating Scale (HAM-D) the hypothesis of Central Nervous System (CNS) cholinergic involvement in patients with Myasthenia Gravis (MG).MethodsThirty-two patients (32) with MG and a mean age of 51.1±17.2 volunteered to participate in this investigation, while thirty-three (33) healthy subjects with a mean age of 50.2±14.8 served as controls. All subjects underwent pupillometric measurements and performed the Wechsler Memory Scale (WMS) and HAM-D. The pupillometric indices studied were: 1) latency for the onset of constriction (T1), 2) maximum constriction velocity (VCmax) and 3) maximum constriction acceleration (ACmax).ResultsT1 was found significantly increased by 21.7% (p<0.05) in MG patients as compared to healthy subjects. Conversely, VCmax and ACmax were significantly decreased in MG patients by 33.3% (p<0.05) and 43.5% (p<0.05) respectively, as opposed to healthy subjects. Additionally, MG patients showed significantly decreased score in WMS by 41.6% (p