Respiratory function deterioration is not time‐linked with upper‐limb onset in amyotrophic lateral sclerosis

Introduction– In amyotrophic lateral sclerosis (ALS), symptoms apparently spread following regional rules, and depending on the site of onset. We examined if respiratory function deterioration appears earlier or is more severe in patients with upper‐limb onset. Material & methods– We compared the results of various pulmonary function tests (PFT) obtained at diagnosis depending on the site of onset in 49 ALS patients. In a longitudinal study, we compared the deterioration of forced vital capacity (FVC) in relation to the site of onset, and analyzed the time elapsed to reach values below 80% of predicted according to site of onset, and we compared the survival depending on the site of onset. Results– No significant differences in PFT were found in the upper‐limb onset group in any of the analysis performed. No differences in survival were detected in any disease onset group. Conclusion– Pulmonary function deterioration does not appear to be time‐linked to arm onset in ALS.