9 predictors for future scleroderma renal crisis in SSc patients
Proteinuria, hypertension and chronic kidney disease (CKD), among others, are associated with the risk of scleroderma renal crisis (SRC) in patients with systemic sclerosis (SSc), reports a study.
“These patients may benefit from close observation of blood pressure, proteinuria and estimated glomerular filtration rate for earlier SRC identification and intervention,” the authors said. “Future prospective therapeutic studies could focus specifically on this high-risk population.”
At SSc diagnosis, the following conditions correlated with future SRC after adjustment for potential confounding variables: proteinuria (odds ratio [OR], 183; 95 percent CI, 19.1–1,750; p<0.001), anaemia (OR, 9.9; 2.7–36.2; p=0.001), hypertension (OR, 13.1; 4.7–36.6; p<0.001), CKD (OR, 20.7; 2.2–190.7; p=0.008), elevated erythrocyte sedimentation rate (OR, 14.3; 4.8–43.0; p<0.001), thrombocytopaenia (OR, 7.0; 1.2–42.7; p=0.03), hypothyroidism (OR, 2.8; 1.2–6.7; p=0.01), Anti-Ro antibody seropositivity (OR, 3.9; 1.6–9.8; p=0.003) and anti-RNA polymerase III antibodies (ARA; OR, 4.1; 1.2–13.8; p=0.02).
At least three of these risk factors present at SSc diagnosis were sensitive (77 percent) and highly specific (97 percent) for predicting future SRC. Furthermore, SSc without SRC disease controls did not have more than four risk factors.
This retrospective cohort study analysed the entire military electronic medical record between 2005 and 2016, and compared the demographics, clinical characteristics and laboratory results at SSc diagnosis for 31 patients who developed SRC after SSc diagnosis to 322 SSc without SRC disease controls.
“SSc is a disease of autoimmunity, fibrosis and vasculopathy, [and] SRC is one of the most severe complications,” the authors said.
“Corticosteroid exposure, presence of ARA, skin thickness and significant tendon friction rubs are among the known risk factors at SSc diagnosis for developing future SRC. Identification of additional clinical characteristics and laboratory findings could expand and improve the risk profile for future SRC at SSc diagnosis,” they added.