Diaphragmatic muscle thickness and diaphragmatic function are reduced in patients with systemic lupus erythematosus compared to those with primary Sjögren's syndrome.

SLE patients had reduced diaphragmatic muscle thickness compared to those with pSS, which was associated with impaired functional tests. Further prospective studies are needed to investigate whether structural and functional impairments in diaphragmatic muscle play a role in an increased risk of pulmonary infections and SLS in patients with SLE.