Myeloproliferative syndromes and the associated risk of coronary artery disease

Of the major myeloproliferative syndromes (MPS) [polycythemia vera (PV), essential thrombocythemia (ET), chronic myeloid leukemia (CML) and myelofibrosis (MF)], PV and ET are reported to be associated with increased thrombotic complications. However, the relationship between these myeloproliferative syndromes and coronary artery disease (CAD) is unclear.

We performed a retrospective chart review to evaluate the prevalence of CAD in patients with diagnosed with MPS between 1991 and 2001.

One hundred and eighty-one patients (100 males, 81 females) with a mean age of 72.5 years were included. Twenty-nine patients, 19 males and 10 females (16%, 95% CI: 12.0-24.0) had CAD. These included 6/53 (11.3%, 95% CI: 1.5-20.2) patients with CML, 1/26 (3.8%, 95% CI: -4.4 to 12.8) patients with PV, 5/30 (16.7%, 95% CI: 2.5-30.8) patients with ET, 3/7 (42.9%, 95% CI: 12.3-87.7) patients with MF and 14/65 (21.5%, 95% CI: 13.1-37.8) patients with co-existent MPS. Comparing the risk of CAD with CML as a baseline, MF had an OR of 8.2 (p < 0.01, 95% CI: 1.7-39), PV-0.4 (p = 0.4, 95% CI: 0.04-3.2), ET-1.6 (p = 0.7, 95% CI: 0.43-6.2) and patients with co-existent MPS-2.8 (p=0.07, 95% CI: 0.91-8.6). However, after adjusting for age, sex, dyslipidemia, diabetes, hypertension and tobacco use, the difference in the prevalence of CAD between the various categories of MPS was not significant.

Contrary to conventional belief, we did not find an increased prevalence of CAD in patients with either PV or ET. In fact, patients with MF had a significantly higher prevalence of CAD. However, this difference appears to be due to the increased age at diagnosis of MF. The conventional risk factors for CAD appear to be the major determinants of CAD among patients with MPS.