Cachexia is a disorder characterized by involuntary weight loss in addition to the loss of homeostatic control of both energy and protein balance. Despite an abundance of data from other inflammatory diseases, cachexia in SLE remains a largely undescribed syndrome.

Two thousand four hundred six patients in a prospective SLE cohort had their weight assessed at each visit. Patients were categorized into five predetermined groups based on weight. Cachexia was defined based on modified Fearon criteria (5% stable weight loss in 6 months without starvation relative to the average weight in all prior visits and weight loss >2% without starvation relative to the average weight prior cohort visits and a BMI <20). The risk of cachexia within five years of cohort entry was based on Kaplan Meier estimates. The association of prior disease manifestations with the risk of cachexia adjusted by current steroid use was determined using Cox regression. An analysis of variance test was used to determine whether the SLICC/ACR Damage Index scores varied based on cachexia status.

Within five years of cohort entry, 56% of patients developed cachexia, 18% of which never recovered their weight in follow up. The risk factors for cachexia development were BMI<20, current steroid use, vasculitis, lupus nephritis, serositis, hematologic, positive anti‐dsDNA, anti‐Sm, and anti‐RNP. Patients with intermittent cachexia had a significantly higher SLICC/ACR Damage Index than those with continuous cachexia or without cachexia.

Cachexia is an underrecognized syndrome in patients with SLE. SLE patients with intermittent cachexia have the highest risk of future organ damage.