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Hypermetabolism in ALS patients: an early and persistent phenomenon
C Bouteloup1, J-C Desport, P Clavelou
1Department of Hepato-Gastroenterology, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France.
Journal of Neurology
|March 24, 2009
Summary
Approximately 50% of patients with Amyotrophic Lateral Sclerosis (ALS) exhibit hypermetabolism, a condition of increased resting energy expenditure (REE). This metabolic status generally remains stable throughout the disease progression, indicating it can be identified early for nutritional support.
Area of Science:
- Neurology
- Metabolism
- Nutrition Science
Background:
- Malnutrition is common in Amyotrophic Lateral Sclerosis (ALS) patients.
- Increased resting energy expenditure (REE) is a potential cause of malnutrition in ALS.
- The origins and progression of hypermetabolism in ALS are not fully understood.
Purpose of the Study:
- To monitor resting energy expenditure (REE) over time in patients with ALS.
- To identify factors influencing variations in REE among ALS patients.
- To assess the stability of metabolic status in ALS.
Main Methods:
- Sixty-one ALS patients were assessed every six months for two years.
- Nutritional, neurological, and respiratory assessments were conducted.
- Measured REE (mREE) was compared to calculated REE (cREE) and normalized for fat-free mass (FFM).
Main Results:
- At baseline, 47.5% of ALS patients showed hypermetabolism (mREE 19.7% higher than cREE).
- Hypermetabolism persisted when normalized for fat-free mass.
- Metabolic status remained largely unchanged over time in 80% of patients, despite disease progression.
Conclusions:
- Approximately 50% of ALS patients exhibit hypermetabolism.
- Metabolic status in ALS patients is generally stable over time and can be assessed early.
- The precise origin of hypermetabolism in ALS remains unclear, with potential mitochondrial involvement.
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