Complex fasciculation potentials and survival in amyotrophic lateral sclerosis

Abstract

Objective: We investigated the relationship between fasciculation potentials (FPs) and survival in patients with ALS.

Methods: In 85 ALS patients, we prospectively performed needle EMG in five to seven muscles of each patient. The shape of the detected FPs was analyzed by inspection, and FPs with >4 phases were judged as complex FPs. We analyzed the correlation between complex FPs and survival period using the Cox proportional hazard model.

Results: Complex FPs were observed in 47 patients, more frequently in the muscles with normal strength or mild weakness. The presence of complex FPs was associated with shorter survival (hazard ratio 3.055; p=0.004). The greater the number of muscles with complex FPs, the shorter the survival and the faster the progression speed.

Conclusion: Wide distribution of complex FPs is associated with shorter survival in ALS.

Significance: Complex FPs are useful to predict prognosis of ALS patients and should be evaluated in the EMG examination.

Keywords: Amyotrophic lateral sclerosis; Complex fasciculation potential; Electromyography; Survival prognosis.