To study hemostasis with reference to rheumatoid arthritis (RA) activity, extraarticular manifestations and vascular damage.
We studied hemostasis in 104 RA patients. The following parameters were tested: partial thromboplastin time activation (PTTA), fibrinolytic activity (FA), prothrombin index, lupus anticoagulant (LA), mean platelet volume (PV), antibodies against cardiolipin (aCL) and antibodies against beta2-glycoprotein 1 (alphabeta2-GP1). The disease activity index was estimated by DAS-28 including tender and swelling joints count, erythrocyte sedimentation rate and disease global activity rated by the patient.
We found out an increased number of platelets in 54.4%, prolongation of FA and PTTA in 72.5 and 12.5% patients. The rest blood coagulation tests were normal in most the examinees. The LA antibodies were absent, while aCL and alphabeta2-GP1 antibodies were identified in 10.6 and 14.4%, respectively. The number of platelets increased while hemoglobin decreased in relation to higher disease activity and PV was significantly lower in patients with extraarticular manifestations. No significant influence of vascular damage or comorbidities on hemostasis was found.
No relation was established between coagulation factors and the disease activity except for increased number of platelets in patients with higher activity and lower PV in patients with extraarticular manifestations. However, patients with aCL and alphabeta2-GP1 need constant monitoring because of the risk to develop thrombosis.