Predictors of severe hemolytic anemia and its impact on major outcomes in systemic lupus erythematosus: Data from a multiethnic Latin American cohort.

OBJECTIVE: To determine the predictors of the occurrence of severe autoimmune hemolytic anemia (AIHA) and its impact on damage accrual and mortality in SLE patients.

METHODS: Factors associated with time to severe AIHA (hemoglobin level ≤7 g/dL) occurring from the onset of SLE symptoms were examined by Cox proportional hazards regressions. The association of severe AIHA with mortality was examined by logistic regression analyses while its impact on damage was by negative binomial regression.

RESULTS: Of 1,349 patients, 49 (3.6%) developed severe AIHA over a mean (SD) follow-up time of 5.4 (3.8) years. The median time from the first clinical manifestation to severe AIHA was 111 days (IQR 43-450). By multivariable analysis, male sex (HR 2.26, 95% CI 1.02-4.75, p = 0.044), and higher disease activity at diagnosis (HR 1.04, 95% CI 1.01-1.08, p = 0.025) were associated with a shorter time to severe AIHA occurrence. Of the SLEDAI descriptors, only hematologic (leukopenia and/or thrombocytopenia) showed a certain trend toward significance in the multivariable analysis (HR 2.36, 95% CI 0.91-6.13, p = 0.0772). Severe AIHA contributed neither to damage nor to mortality.

CONCLUSIONS: Severe AIHA occurs during the early course of SLE. Male sex and higher disease activity at diagnosis emerged as independent predictors of a shorter time to severe AIHA occurrence. Although not statistically significant, hematological abnormalities at SLE diagnosis could predict the occurrence of severe AIHA in a shorter time. Damage and mortality did not seem to be impacted by the occurrence of severe AIHA.