Thrombotic burden and longitudinal outcomes in Thai patients with polycythemia vera.
In a cohort of Thai patients with polycythemia vera, 38.3% experienced thromboembolic events, predominantly arterial, and the 5-year overall survival was 82.7%.
Where it sits
this study against the rest of the erythropoietin (epo) corpusSummary and findings
This study evaluated thromboembolic events, treatment-related complications, disease progression, and overall survival in 133 Thai patients with polycythemia vera (PV). The median age was 61 years, and 51 patients (38.3%) experienced at least one thromboembolic event. The 5-year overall survival rate was 82.7%.
Abstract
Background Polycythemia vera (PV) is a myeloproliferative neoplasm frequently complicated by thromboembolic events. However, data regarding thrombotic burden and long-term outcomes among Asian patients remain limited. Materials and methods We conducted a retrospective cohort study at a tertiary referral center to evaluate thromboembolic events, treatment-related complications, disease progression, and overall survival in patients with PV. Results A total of 133 patients were included, with a median age of 61 years (range 18-88). Most patients were male (60.2%). Fifty-one patients (38.3%) experienced at least one thromboembolic event, with 54 events in total, of which 87% occurred before or at PV diagnosis. Arterial thrombosis accounted for 90.7% of all events. Age ≥60 years was significantly associated with thromboembolic events, with an odds ratio of 2.34 (95% confidence interval [CI], 1.07-5.11). After a median follow-up of 7.7 years, the 5-year overall survival was 82.7% (95% CI, 74.61-88.35). Prior thrombosis was associated with an increased risk of death (hazard ratio, 1.98; 95% CI, 1.15-3.42). Hydroxyurea resistance or intolerance occurred in 9.8% of patients. Bleeding complications were observed in 6.8%, including major bleeding in 4.5%. Fibrotic transformation, leukemic transformation, and secondary solid malignancies occurred in 4.5%, 3.8%, and 6.0% of patients, respectively. Conclusion Thromboembolic events were common and predominantly arterial in this Asian PV cohort, occurring mainly before or at diagnosis. Prior thrombosis was associated with inferior survival. Long-term follow-up also revealed disease progression and secondary solid malignancies, underscoring the importance of continued surveillance.
Background
This paper addresses the thrombotic burden and long-term outcomes in patients with polycythemia vera (PV), a myeloproliferative neoplasm associated with thromboembolic events. Prior studies have indicated that thrombotic events are common in PV, but data specifically regarding Asian populations are limited. Understanding these outcomes is crucial for managing PV and improving patient care.
Methods
The study employed a retrospective cohort design, including 133 patients with PV from a tertiary referral center. The median age of participants was 61 years, with a range of 18 to 88 years. The study assessed thromboembolic events, treatment complications, disease progression, and overall survival, with a median follow-up of 7.7 years.
Results
The primary endpoint revealed that 51 patients (38.3%) experienced at least one thromboembolic event, with a total of 54 events. The majority (90.7%) of these events were arterial thromboses. The 5-year overall survival rate was 82.7% (95% CI, 74.61-88.35). Prior thrombosis was associated with a hazard ratio of 1.98 (95% CI, 1.15-3.42) for increased mortality.
Interpretation
These findings align with existing literature indicating a high prevalence of thromboembolic events in PV, particularly arterial events. The effect sizes reported, while statistically significant, may not be clinically meaningful for all practitioners, especially given the nature of retrospective studies. Limitations include the retrospective design and potential biases, which may affect the reliability of the conclusions drawn.
Key findings
- 51 patients (38.3%) experienced at least one thromboembolic event, with a total of 54 events.
- Arterial thrombosis accounted for 90.7% of all thromboembolic events.
- Age ≥60 years was significantly associated with thromboembolic events, with an odds ratio of 2.34 (95% CI, 1.07-5.11).
- The 5-year overall survival was 82.7% (95% CI, 74.61-88.35) after a median follow-up of 7.7 years.
- Prior thrombosis was associated with an increased risk of death, with a hazard ratio of 1.98 (95% CI, 1.15-3.42).
- Hydroxyurea resistance or intolerance occurred in 9.8% of patients.
Limitations
- Retrospective cohort design may introduce bias.
- Follow-up duration of 7.7 years may not capture all long-term outcomes.
- Small sample size (n=133) limits generalizability.
- Lack of control group for comparison.
- Not all treatment-related complications were detailed.