Pb2212: abdominal aortic calcification in patients newly diagnosed with philadelphia-negative myeloproliferative neoplasm

Topic: 16. Myeloproliferative neoplasms - Clinical Background: Although atherosclerosis is likely to be involved in the development of arterial thrombotic events in patients with Philadelphia chromosome-negative myeloproliferative neoplasm (Ph− MPN), studies on the prevalence and severity of atherosclerosis in these patients are scarce. Arterial calcification is the end stage of stabilized atherosclerotic plaques, and abdominal aortic calcification (AAC) is a predictor of vascular morbidity and mortality. However, AAC has seldom been evaluated in Ph− MPN patients. Aims: We retrospectively evaluated the presence and clinical relevance of AAC using abdominal computed tomography (CT) performed at the time of diagnosis of Ph− MPN. Methods: We enrolled patients with essential thrombocythemia (ET), polycythemia vera (PV), or prefibrotic/early primary myelofibrosis (pre-PMF) who underwent abdominal CT at the time of diagnosis between January 2002 and December 2021 at Chungnam National University Hospital, Daejeon, Korea. The abdominal CT images were reviewed and an Agatston score was assigned. Results: Of the 334 patients newly diagnosed with Ph− MPN (150, 48, and 136 with ET, pre-PMF, and PV, respectively) during the study period, 198 (59.3%), including 94 with ET (median age: 62 years; range: 18−90), 24 with pre-PMF (median age: 67.5 years; range: 31−88), and 80 with PV (median age: 64.5 years; range: 18−66) were enrolled. The patients were followed up for a median of 3.4 years (range: 0.1−20.2 years). AAC was detected in 139 (70.2%) of the 198 Ph− MPN patients. The prevalence of AAC in ET patients was 66%, which did not differ from that in pre-PMF (70.8%; p = 0.534) and PV (75.0%; p = 0.223) patients. Old age (odds ratio [OR] = 34.7; 95% confidence interval [CI] = 12.32−95.91; p < 0.001), male sex (OR = 2.46; 95% CI = 1.34−8.95; p = 0.010), leukocytosis (OR = 3.07; 95% CI = 1.21−7.80; p = 0.010), and dyslipidemia (OR = 3.58; 95% CI = 1.02−12.55; p = 0.046) were independent risk factors for the presence of AAC at the time of MPN diagnosis. The Agatston score was positively correlated with age (r = 0.435, p < 0.001), white blood cell count (r = 0.186, p = 0.009), neutrophil-to-lymphocyte ratio (r = 0.189, p = 0.008), monocyte count (r = 0.218, p = 0.002), and lactate dehydrogenase level (r = 0.209, p = 0.003). AAC was an independent risk factor for arterial thrombotic events that occurred before or at the time of diagnosis (OR = 2.62; 95% CI = 1.06−6.46; p = 0.037). AAC was an independent risk factor for arterial thrombotic events in ET patients (OR = 4.12; 95% CI = 1.11−15.85; p = 0.034) but not in PV patients. The overall survival (OS) of Ph− MPN patients with AAC was significantly worse than that in Ph− MPN patients without AAC (15-year OS: 91.7% vs. 47.3%, respectively; p < 0.001). The presence of AAC was an independent risk factor for OS of Ph− MPN patients (HR = 11.22; 95% CI = 1.40−88.89; p = 0.023). Summary/Conclusion: AAC is common in Ph− MPN patients and is associated with the development of arterial thrombotic events and poor survival in these patients. Keywords: Atherosclerosis, Arterial thrombosis, Myeloproliferative disorder