The Effect of Heparin and Dicumarol Anticoagulant Therapy upon the Erythrocyte Sedimentation Rate.

Anticoagulant therapy has been employed in thromboembolic disease with increasing frequency during the past few years. There has been a striking lack of unanimity in the literature (1 to 15) as to the effect of heparin or dicumarol per se upon the erythrocyte sedimentation rate. In view of the fact that anticoagulants are frequently employed in disorders in which the sedimentation rate is of importance in diagnosis as well as in judging their progress, definitive information concerning the effect of anticoagulants on the erythrocyte sedimentation rate would be of considerable practical value. The sedimentation rate of heparinized blood has been reported to be greater than that of citrated or oxalated blood (1, 2). This has been ascribed not to an accelerating effect of heparin but rather to a stabilizing and retarding influence exerted by the oxalate and citrate salts upon the red blood cell sedimentation (1 to 5). Conflicting observations have been reported (6, 7) as regards the effect upon the citrated sedimentation rate when heparin was added in vitro to blood specimens. It has been noted (5, 8) that heparin in unusually large concentrations resulted in an acceleration of the sedimentation rate. Furthermore, during venous clotting time determinations in a patient receiving heparin therapy, it is a frequent observation that the plasma and cells of the blood of a well heparinized patient will separate more rapidly than usual in the clotting time test tubes. This phenomenon has been remarked on (9, 10) and has given the impression that in a patient receiving heparin therapy the sedimentation rate is quite briskly increased. Previous observations as to the effect of dicumarol on the sedimentation rate also are not in accord (11 to 15). It has been reported (11) that the erythrocyte sedimentation rate is not elevated by dicumarol therapy per se. However, in several later communications (12 to 14) it was stated that the sedimentation rate was increased by dicumarol to such an extent that its reliability and dependability as a guide to healing was compromised. Recently one of these groups (15) has reversed its original stand (12) and stated that dicumarol probably has little, if any, effect on the sedimentation rate. The present study was initiated to determine whether the sedimentation rate may still be accorded clinical significance in a patient who is receiving anticoagulant therapy.