Energy expenditure, body composition and dietary habits in progressive supranuclear palsy

INTRODUCTION: Little is known about metabolic changes in progressive supranuclear palsy. Goals of the present study are to: (1) investigate whether early progressive supranuclear palsy is associated with changes in energy expenditure, body composition and dietary intake compared with Parkinson’s disease and healthy controls; (2) assess the accuracy of the Harris–Benedict equation to predict measured rest energy expenditure in progressive supranuclear palsy; (3) verify differences according to sex, phenotypes, disease severity and presence of dysphagia in progressive supranuclear palsy. METHODS: Twenty-one progressive supranuclear palsy, 41 Parkinson’s disease and nine healthy controls were included. Rest energy expenditure was assessed with indirect calorimeter, body composition with bio-impedance analysis and physical activity and dietary intake were estimated with a validated frequency questionnaire. Parametric testing was used to analyze differences between groups. RESULTS: Progressive supranuclear palsy showed reduced total daily energy expenditure and physical activity compared to both other cohorts (p < 0.001) and a tendency toward lower fat-free mass compared to Parkinson’s disease (p > 0.05). Limited accuracy was shown for the Harris–Benedict equation (accurate prediction frequency < 60%). Greater disease severity was associated with lower rest energy expenditure (p = 0.030), fat-free mass (p = 0.026) and muscle mass (p = 0.029). CONCLUSION: Greater disease severity is associated with reduction in rest energy expenditure likely due to the reduction in lean mass and muscle mass. Such data may pave the way to clinical trials evaluating the efficacy of muscle-targeted nutritional support and physical therapy in preserving muscle mass and improving motor performances in progressive supranuclear palsy at early stages. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00415-021-10846-6.