Nerve Conduction Study and the Prognosis of Amyotrophic Lateral Sclerosis: Exploration of Additional Neuroelectrophysiological Parameters.

OBJECTIVE

To investigate the correlation between nerve conduction study (NCS) parameters and the prognosis of patients with amyotrophic lateral sclerosis (ALS).

METHODS

NCS parameters were recorded from the median, ulnar, peroneal, tibial, and superficial peroneal nerves of 114 sporadic patients with ALS. The main endpoint was death or tracheostomy. Univariate Cox regression analysis was conducted for all the NCS parameters. Subsequently, multivariate analysis was performed using Cox stepwise regression, incorporating factors identified in the univariate analysis and known prognostic factors. Kaplan-Meier curves and log-rank tests were used for survival analysis. Receiver operating characteristic (ROC) curves were used to assess the predictive capabilities of NCS parameters.

RESULTS

The distal compound muscle action potential (dCMAP) negative peak area and the sensory nerve action potential (SNAP) amplitude of the median nerve were identified as prognostic factors for ALS. Further stratified analyses showed that larger median dCMAP negative peak area significantly correlated with better prognosis in elderly (> 61 years) patients with limb-onset ALS. Conversely, higher median SNAP amplitudes indicated worse prognosis in younger (≤ 61 years) patients with limb-onset ALS.

CONCLUSION

The current study showed that the dCMAP negative peak area and SNAP amplitude of the median nerve are independent prognostic factors for sporadic ALS patients.