To assess the effect of caloric balance on disease-severity and progression measured by change in the ALS Functional Rating Score -revised (ALSFRSR) and forced vital capacity (FVC).

Caloric intake suffers in ALS patients due to poor nutrition while caloric expense is increased by hypermetabolism and inefficient use of calories during physical activity. Caloric imbalance, weakness, and fatality eventually result (1). 

Data on 103 patients from our center from are included to date. The estimated total daily caloric requirement (TDCR) was calculated using an ALS-specific version of the Harris-Benedict equation (HBE) (2) where TDCR = [(Basal Metabolic Rate from HBE) + (55.96 x ALSFRSR-6) – 168 kcal/day] (3). Caloric Balance (CB) was calculated as CB = [(daily caloric intake / TDCR) x 100]. Patients were categorized as being below, within, or above CB thresholds of 5%, 10%, 15%, and 20%. Patients were further stratified based on ALSFRSR scores, FVC, and rate of disease progression at baseline. 

Patients with TDCR >10% (p = 0.04) and >15% (p = 0.02) compared to intake had slower rates of disease progression (-0.37 and –0.47, respectively) compared to patients below or within 5% CB. Detailed results on a larger sample size will be presented later. 

Patients with positive CB >10% and >15% have slower rates of decline of ALSFRS-R scores compared to patients at or below the 5% threshold. Results have implications for early nutritional care in ALS.