PT03.3: Hypermetabolism is a Deleterious Prognostic Factor in Patients with Amyotrophic Lateral Sclerosis

Abstract

Rationale: Hypermetabolism, defined as an excessive level of resting energy expenditure (REE) has been reported in 50 –60% of patients with amyotrophic lateral sclerosis (ALS). The aim of this study was to investigate a large cohort of ALS patients in order to determine their nutritional, neurological and respiratory parameters and their survival according to the metabolic level. Methods: Nutritional, neurological and respiratory assessments were prospectively recorded. Nutritional evaluationincluded body mass index, REE measured by indirect calorimetry (hypermetabolism if REE variation [ΔREE] >10%) and fat mass (FM) using impedancemetry. Neurological evaluation included ALS phenotype at time of diagnosis, site at onset, ALSFRS-R score. Respiratory evaluation included vital capacity and SNIFF test. Survival analysis used the Kaplan-Meier method and the multivariate Cox model. Results: 315 patients were analysed. Median age at diagnosis was 65.9 years. 55.2% of patients were hypermetabolic. According to the metabolic level (Δ REE 20%), patients with a Δ REE >20% initially had a lower FM, 29.7% vs. 32.1% in those ≤ 10% (p = 0.0054). SNIFF test tended to be lower in ALS patients with Δ REE >20% (p = 0.07). During follow-up, nutritional status did not differ between the three groups, The median slope of ALSFRS-R tended to evolve more severely in patients with Δ REE >20%, −1.4 points/month vs. − 1.0 points/month in those ≤ 10% (p = 0.07). Overall median survival since diagnosis was 18.4 months. Δ REE >20% tended to increase the risk of dying compared to ≤ 10% (HR = 1.33, p = 0.055). In multivariate analysis, an increased REE/FM ratio was independently associated with death (HR = 1.005, p = 0.001). Conclusion: Hypermetabolism is present in more than half of ALS patients. It modifies the body composition at diagnosis, and patients with hypermetabolism >20% have a worse prognosis.