Cytoreductive treatment patterns among US veterans with polycythemia vera

BMC Cancer

Table 4 Thrombotic Events, Cardiovascular Events, and Deaths Occurring During the Follow-Up Period

Event	Patients With ≥1 Event, n (%)	Mean Time to First Event, y	Patient-Years^a	Event Rate, per 1000 Patient-Years^b	95% CI of Event Rate
Among all patients with PV (N = 7718)
Thrombotic event	1771 (22.9)	1.4	29,276.2	60.5	57.7–63.4
Arterial	1275 (16.5)	1.5	30,874.3	41.3	39.1–43.6
Ischemic stroke	825 (10.7)	1.4	32,216.2	25.6	23.9–27.4
Transient ischemic attack	344 (4.5)	1.6	33,609.5	10.2	9.2–11.4
Acute myocardial infarction	224 (2.9)	2.3	34,167.1	6.6	5.8–7.5
Peripheral arterial thrombosis	109 (1.4)	2.0	34,364.7	3.2	2.6–3.8
Venous	678 (8.8)	1.4	32,621.4	20.8	19.3–22.4
Deep vein thrombosis	535 (6.9)	1.4	32,992.0	16.2	14.9–17.7
Pulmonary embolism	234 (3.0)	1.7	34,029.2	6.9	6.1–7.8
Superficial thrombophlebitis	42 (0.5)	1.9	34,529.8	1.2	0.9–1.7
Cardiovascular event	2325 (30.1)	1.4	27,750.5	83.8	80.4–87.3
Heart failure	1442 (18.7)	1.5	30,730.4	46.9	44.6–49.4
Ischemic stroke	825 (10.7)	1.4	32,216.2	25.6	23.9–27.4
Transient ischemic attack	344 (4.5)	1.6	33,609.5	10.2	9.2–11.4
Acute myocardial infarction	224 (2.9)	2.3	34,167.1	6.6	5.8–7.5
Unstable angina	185 (2.4)	2.3	34,193.5	5.4	4.7–6.3
Percutaneous coronary intervention	78 (1.0)	2.0	34,444.8	2.3	1.8–2.8
Coronary artery bypass graft	7 (0.1)	2.0	34,624.2	0.2	0.1–0.4
Mortality	1776 (23.0)	2.8	34,684.6	51.2	48.9–53.6
Among patients with PV receiving cytoreductive treatment (n = 1522)
Thrombotic event	295 (19.4)	2.2	6032.3	48.9	43.6–54.8
Among patients with PV not receiving cytoreductive treatment (n = 6196)
Thrombotic event	1476 (23.8)	1.2	23,243.8	63.5	60.3–66.8

PV polycythemia vera
^aUp to the first respective event after diagnosis or end of the study period, whichever occurred first
^bRate per 1000 patient-years was defined as 1000 × number of patients with first event/patient-years of total patients with PV

ISSN: 1471-2407