Body weight variation predicts disease progression after invasive ventilation in amyotrophic lateral sclerosis

Weight loss is an independent predictor of survival in the early stages of amyotrophic lateral sclerosis (ALS). However, the effects of weight variations on the functional prognosis after tracheostomy and invasive ventilation (TIV) in ALS remain unknown. This prospective cohort study aimed to investigate the relationship between weight loss before TIV and disease progression after TIV in ALS patients. Sixty ALS patients with TIV were enrolled and classified into subgroups based on the rate of decline in body mass index, from onset to TIV utilization (ΔBMI). During follow-up, we assessed the patients for presence of communication impairments, ophthalmoplegia, total quadriplegia, mouth opening disability, and dysuria. We analyzed the relationship between ΔBMI and the communication stage or motor disabilities. The log-rank test showed that patients with a ΔBMI ≥ 1.7 kg/m²/year showed a shorter period of preserved communication ability (p = 0.0001), shorter time to develop ophthalmoplegia (p = 0.0001), total quadriplegia (p < 0.0001), mouth opening disability (p < 0.0001), and dysuria (p = 0.0455). Cox multivariate analyses showed that a larger ΔBMI was an independent prognostic factor for the early development of ophthalmoplegia (p = 0.0400) and total quadriplegia (p = 0.0445). Weight loss in the early stages of ALS predicts disease progression in patients with advanced stages of ALS using TIV.