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

Abstract

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<0.0001). ALSFRSR was not significantly different but FVC was lower in ALS/FTD patients (79.5% (61.0 e 95.3) vs. 93.0% (70.8 e 106.3), p¼0.042). ALS/FTD patients had a lower body mass index (21.8 kg/m2 (19.8 e 25.8) vs. 24.3 kg/m2 (22.2e 27.5), p¼0.014), were more malnourished (24.0% vs. 8.3%, p¼0.008) and with a higher weight loss (-10.3% (-15.4 e -5.7) vs -5.0% (-11.3 e -0.2), p¼0.004). Body composition was not significantly different between the two groups. However, ALS/FTD had less often a REE variation over 10% (32.0% vs. 53.9%, p¼0.03). ALS/FTD patients had more often gastrostomy placement (68.0% vs. 40.1%, p¼0.006). In univariate analysis, ALS/FTD patients had an increased risk of death compared to ALS patients (HR ¼ 1.97 [1.31 e 2.97], p¼0.001) but not in multivariate analysis. In multivariate analysis, regardless of type of ALS (ALS and ALS/DFT) a higher fat mass (þ1%)was associated with a reduced risk of death (HR ¼ 0.98 [0.96 e 0.99], p¼0.03) and a greater weight loss (-1%) with an increased risk of death (HR ¼ 1.03 [1.02 e 1.05], p<0.0001). Conclusion: ALS/FTD patients would seem to have a lower survival compared to patients with ALS alone. However, this is not found after adjustment in multivariate analysis. Regardless of the form of ALS, as described previously in literature, nutritional status and body composition were associated with the risk of death. Early nutritional assessment and management are essential in this severe neurodegenerative disease whatever the form of ALS