Severe thrombocytopenia is associated with high mortality in systemic lupus erythematosus-analysis from Indian SLE Inception cohort for Research (INSPIRE).

ABSTRACT

Thrombocytopenia in patients with systemic lupus erythematosus (SLE) is associated with higher morbidity and mortality. We report frequency, associations and short-term outcome of moderate-severe thrombocytopenia in a prospective inception cohort from India (INSPIRE). We evaluated consecutive SLE patients classified per SLICC2012 for the occurrence of thrombocytopenia and its associations. The outcomes assessed included bleeding manifestations, kinetics of thrombocytopenia recovery, mortality and recurrence of thrombocytopenia. Among a total of 2210 patients in the cohort, 230 (10.4%) had incident thrombocytopenia, of whom moderate (platelet count [PC] 20-50 × 109/L) and severe thrombocytopenia (PC < 20 × 109/L) were noted in 61 (26.5%) and 22 (9.5%), respectively. Bleeding manifestations were generally limited to the skin. Compared to controls, cases had a higher proportion of autoimmune haemolytic anaemia (p < 0.001), leukopenia (p < 0.001), lymphopenia (p < 0.001), low complement (p < 0.05), lupus anticoagulant (p < 0.001), higher median SLEDAI 2 K (p < 0.001) and lower proportion of anti-RNP antibody (p < 0.05). There was no significant difference in these variables between moderate and severe thrombocytopenia. There was a sharp rise in PC by 1 week that was sustained in the majority through the period of observation. There was three times higher mortality in the severe thrombocytopenia group as compared to moderate thrombocytopenia and controls. The thrombocytopenia relapse and lupus flare rates were similar across categories. We report a low occurrence of major bleeds and higher mortality in those with severe thrombocytopenia as compared to moderate thrombocytopenia and controls. Key Points • Severe thrombocytopenia occurs in 1% of patients with SLE; however, major bleeds are uncommon. • Thrombocytopenia has a strong association with other lineage cytopenias and lupus anticoagulants. • Response to initial glucocorticoids therapy is quick and is well sustained with additional immunosuppressants. • Severe thrombocytopenia increases mortality threefold in SLE.