The diaphragm is an essential skeletal muscle responsible for respiration [1]. However, the significance of measuring its muscle mass and function remains largely unexplored. In particular, it is unclear whether sarcopenia, a geriatric syndrome associated with progressive loss of skeletal muscle mass and strength [2], can occur in the diaphragm. Pneumonia is one of the major causes of death in developed countries [3], and association between sarcopenia and pneumonia has been previously documented [4].
