Nutritional and metabolic status at diagnosis and survival of patients with Amyotrophic Lateral Sclerosis (ALS) and frontotemporal dementia (FTD) compared to patients with ALS alone

Rationale: About 5%e10% of ALS patients suffer from frank ALS/FTD. In ALS, the increase of resting energy expenditure (REE) is a prognostic factor for the survival. No studies have investigated nutritional and metabolic status in ALS/FTD and its impact on survival. The aims of this study were i) to study nutritional and metabolic status of ALS/FTD compared to ALS patients, ii) to study the survival according to the disease and the metabolic status. Methods: Three months after diagnosis, nutritional assessments and body composition (by bioimpedance analysis) were performed in all patients. REE measured (mREE) by indirect calorimetry and calculated (cREE) by Harris and Benedict 1919 formula were used for the calculation of REE variation. Neurological (bulbar onset), functional (ALS Functional Rating Scale e Revised [ALSFRS-R]) and respiratory (Forced Vital Capacity [FVC]) assessments were collected. Survival by Log-rank test (Hazard Ratio [HR], confidence interval 95%) and multivariate analysis with Cox model were also used. Results were expressed as median (interquartile range). Results: 446 patients were included, 421 ALS patients and 25 (5.6%) ALS/FTD patients. Age at diagnosis and sex were not significantly different. ALS/ FTD patients had more bulbar onset (100.0% vs. 34.5%, p