Malnutrition in Amyotrophic Lateral Sclerosis: Insights from Morphofunctional Assessment and Global Leadership Initiative on Malnutrition Criteria

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease frequently accompanied by malnutrition due to weight loss, increased energy expenditure, and muscle mass loss. This study aimed to evaluate morphofunctional assessment tools as predictors of malnutrition and to investigate their relationship with muscle status and disease severity in ALS patients. A cross-sectional study was conducted with 45 ALS patients at the San Cecilio University Hospital in Granada. Malnutrition was assessed using the Global Leadership Initiative on Malnutrition (GLIM) criteria. Morphofunctional assessment was performed using Bioimpedance Vectorial Analysis (BIVA), handgrip strength (HGS), and Short Physical Performance Battery (SPPB). Malnutrition prevalence was 38% according to GLIM criteria. Significant differences were observed between malnourished and non-malnourished groups in age (70 +/- 9 vs. 62 +/- 10 years, p = 0.01), sex (female prevalence: 58.8% vs. 25.0%, p = 0.02), dysphagia prevalence (83% vs. 29%, p < 0.001), PEG/PRG use (35.3% vs. 3.6%, p = 0.01), and ALSFRS-R scores (30 +/- 12 vs. 34 +/- 12, p = 0.02). Malnourished patients had lower values in anthropometric measurements, muscle mass obtained by BIVA, and phase angle (PA) (4.05 +/- 0.8 degrees vs. 5.09 +/- 0.8 degrees, p < 0.001). No significant differences were found in muscle strength or functional status. PA showed significant correlations with muscle strength (r = 0.52, p < 0.001) and muscle mass measures (r = 0.48, p < 0.001). Moreover, PA was associated with poorer disease progression and physical performance. In our sample, BIVA metrics such as PA (<4.3 degrees), SPA (<-0.8), body cell mass (<9.2 kg/m), and extracellular water (>49.75%) were identified as malnutrition risk factors. The study underscores the critical importance of comprehensive morphofunctional assessment and the use of advanced diagnostic criteria, for early identification and intervention in malnutrition among people with ALS. Further research is warranted to validate these findings and develop targeted nutritional strategies into routine clinical practice.