Thrombophilia in 153 Patients With Premature Cardiovascular Disease ≤Age 45.

We assessed contributions of thrombophilia to premature cardiovascular disease (CVD) events (≤ age 45) in 153 patients. Test results of thrombophilia-hypofibrinolysis were obtained in 153 patients with CVD ≤ age 45, 110 healthy normal controls, and 110 patients who had venous thromboembolism (VTE) without CVD. Of the 153 patients with CVD, 121 (79%) had sustained myocardial infarction, 70 (46%) had coronary artery stenting, and 53 (35%) had coronary artery bypass grafts. The first CVD events occurred at ages >20 to 35 in 47 patients and at ages >35 to 45 in 106 patients. At study entry, median low-density lipoprotein cholesterol was 126 mg/dL, 56 (37%) smoked, 56 (37%) had hypertension, and 56 (37%) were diabetic. Cases differed from normal controls for high factor VIII (10 [22%] of 45 vs 7 of 103 [7%], P = .007), high homocysteine (32 [21%] of 151 vs 5 [5%] of 107, P = .0002), low free protein S (5 [11%] of 44 vs 2 [2%] of 96, P = .032), high anticardiolipin antibodies (ACLA) IgM (11 [9%] of 129 vs 2 [2%] of 109, P = .024), high lipoprotein (a) [Lp(a)] (46 [30%] of 151 vs 21 [19%] of 110, P = .038), and the lupus anticoagulant (4 [11%] of 37 vs 2 [2%] of 110, P = .035). There were no differences ( P > .05) between cases and VTE controls except free protein S and Lp(a). Free protein S was more often low in VTE controls (24 [28%] of 85 vs 5 [11%] of 44, P = .03) and Lp(a) was more often high in cases (46 [30%] of 151, VTE controls 12 [17%] of 71, P = .032). In 153 patients with premature CVD ≤ age 45, thrombophilia was pervasive (high factor VIII, homocysteine, ACLA IgM, low free protein S, high Lp(a), and lupus anticoagulant), evidencing thrombotic contribution to premature CVD. Moreover, thrombophilia in patients with premature CVD was comparable to VTE controls, emphasizing the pervasive nature of thrombophilia in premature CVD.