Neck flexion weakness predicts respiratory dysfunction in amyotrophic lateral sclerosis.

Area of Science:

• Neurology
• Pulmonology
• Biomarkers

Background:

• Neck flexion (NF) weakness is common in amyotrophic lateral sclerosis (ALS), especially in advanced stages.
• The potential of NF weakness as a biomarker for respiratory dysfunction in ALS requires further investigation.

Purpose of the Study:

• To evaluate if neck flexion weakness can serve as a clinical biomarker for the development of respiratory dysfunction in ALS patients.
• To determine the correlation between NF weakness and respiratory function parameters.

Main Methods:

• Prospective recruitment of 62 ALS patients.
• Assessment of neck flexion strength using the Medical Research Council (MRC) score and handheld dynamometry (HHD).
• Evaluation of respiratory function via spirometry, measuring forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1).

Main Results:

• Neck flexion weakness (MRC ≤4) was observed in 27% of ALS patients.
• Significant reduction in FVC was noted in patients with NF weakness compared to those with normal NF.
• HHD measurements of NF strength strongly correlated with FVC and FEV1, particularly in bulbar-onset ALS.
• NF weakness (MRC ≤4) significantly predicted reduced FVC (≤50% predicted), indicating a need for ventilatory support.

Conclusions:

• Neck flexion weakness, assessed by MRC score and HHD, is a valuable marker for respiratory dysfunction in ALS.
• This clinical assessment can help identify patients at risk of respiratory compromise and the need for ventilatory support.