Low platelet count linked to thrombosis in aPL carriers

(HealthDay)—For antiphospholipid antibody (aPL) carriers, low platelet count is associated with increased risk of developing thrombosis, according to a study published online June 29 in the Journal of Thrombosis and Haemostasis.

Ryo Hisada, from Hokkaido University in Sapporo, Japan, and colleagues examined the impact of platelet count in terms of predicting thrombotic events in aPL carriers in a retrospective study comprising 953 consecutive patients suspected to have autoimmune disease. Thrombotic risk was stratified by combining platelet count and antiphospholipid score (aPL-S).

The researchers observed a negative correlation between aPL-S and platelet count (r = −0.2477). Among patients who were aPL-positive, thrombosis developed more frequently in those with low platelet count versus those without (hazard ratio, 2.95). For aPL-negative patients, regardless of platelet count, there was no difference in the predictive value of thrombosis. Patients with low platelet count developed thrombosis more frequently than those without among patients with low aPL-S, (hazard ratio, 3.44); regardless of platelet count, patients with high aPL-S developed thrombosis frequently.

"aPL carriers with low platelet count are at high risk of developing thrombosis," the authors write. "In particular, 'low aPL-S carriers' may be stratified by platelet count in terms of predicting future thrombotic events."

Several authors disclosed financial ties to the pharmaceutical industry.