Clinical Summary: 

• Design/Population: This retrospective study evaluated patients with World Health Organization-defined essential thrombocythemia at a tertiary hematology center, comparing clinical characteristics, cardiovascular comorbidities, driver mutation status, treatment, and outcomes according to thrombosis occurrence.
• Key Outcomes: Patients who developed thrombosis were older and had a greater cardiovascular comorbidity burden, with hyperlipidemia significantly more common and hypertension showing a similar trend. Thrombosis was also associated with substantially higher all-cause mortality.
• Clinical Relevance: These findings identify hyperlipidemia as a potentially underrecognized contributor to thrombotic risk in essential thrombocythemia and suggest that cardiovascular comorbidities may warrant greater consideration alongside established risk factors when developing thromboprophylaxis strategies.

Results from a retrospective, real-world study suggest that cardiovascular comorbidities, particularly hyperlipidemia, may contribute to thrombotic risk among patients with essential thrombocythemia, highlighting the potential value of incorporating broader cardiovascular risk assessment into thrombosis prevention strategies.

These results were presented by Elmir Israfilov, MD, Hacettepe University, Ankara, Turkey, at the Society of Hematological Oncology (SOHO) Annual Meeting in Houston, Texas. 

Investigators analyzed 152 patients with World Health Organization-defined essential thrombocythemia treated at a tertiary hematology center over a median follow-up of 8.6 years. Patients were stratified according to whether they experienced thrombosis, with 30 patients developing thrombotic events and 122 remaining without thrombosis. Demographic characteristics, laboratory parameters, driver mutations, cardiovascular comorbidities, IPSET-thrombosis classification, cytoreductive treatment, and disease outcomes were compared between groups.

Overall, thrombosis occurred in 19.7% of patients. Among patients with thrombosis, 73.3% experienced a single event and 26.7% experienced at least 2 events. Cerebrovascular events were the most common, accounting for 36.7% of thrombotic events, while vital organs were involved in 50% of cases.

Patients who experienced thrombosis were significantly older than those without thrombosis, with mean ages of 68.1 and 59.4 years, respectively (P = .008). Patients with thrombosis were also more frequently male, although the abstract did not report statistical significance for this comparison.

JAK2 V617F mutations were identified more frequently among patients who developed thrombosis compared with those who did not, at 63.3% versus 42.2%, respectively, although the difference did not reach statistical significance (P = .058). Baseline hematologic parameters were comparable between the groups.

Cardiovascular comorbidities were more prevalent among patients who developed thrombosis. Hyperlipidemia was present in 36.7% of patients with thrombosis compared with 18.9% of those without thrombosis (P = .048). Hypertension was also more common in the thrombotic group, occurring in 63.3% versus 44.4%, although this represented a trend rather than a statistically significant association (P = .090).

IPSET-thrombosis classification strongly differentiated the groups, with 90% of patients who developed thrombosis categorized as high risk compared with 16.7% of patients without thrombosis (P < .001).

Notably, thrombotic events were not limited to patients who had not received cytoreduction. Nine patients, representing 30% of those with thrombosis, experienced an event despite cytoreductive therapy, underscoring persistent thrombotic risk despite disease-directed treatment.

Thrombosis was also associated with substantially worse survival outcomes. All-cause mortality occurred in 40% of patients with thrombosis compared with 8.9% of patients without thrombosis (P < .001), representing more than a 4-fold difference between groups.

The investigators concluded that the greater prevalence of hyperlipidemia among patients who developed thrombosis may identify an underrecognized component of cardiovascular risk in essential thrombocythemia. Hypertension showed a similar numerical association, while older age and JAK2 V617F positivity were also more frequent among patients with thrombotic events.

Source: 

Israfilov E. Cardiovascular risk burden and thrombotic outcomes in essential thrombocythemia: A 152-patient real-world cohort with 8.6-tear median follow-up. Presented at the SOHO Annual Meeting; September 9-12, 2026; Houston, Texas. Abstract MPN-821.