Blood Clot Risk Remains High for Patients With Newly Diagnosed Myeloma, Even With Aspirin Use

In a retrospective review of patient records, presented at the American Society of Clinical Oncology (ASCO) Annual Meeting in 2025, researchers examined the occurrence of blood clots in patients who had only recently been diagnosed with multiple myeloma. The focus was on how well the scores on the risk tools SAVED and IMPEDE can predict who is at higher risk for clots and whether using aspirin or blood thinners helps prevent them.

The researchers reviewed electronic medical records of 178 patients who were treated between January 2017 and May 2022. The average age of patients was 65 years (range, from 39 to 88). Each patient had been observed for at least 2 years or until they died. The majority of patients (63.5%) were given an immunomodulatory drug, which can cause an increased risk for clots. Nearly half of the patients (43%) had stem cell transplants in addition to drug therapy.

The SAVED and IMPEDE scores help doctors estimate whether someone is likely to experience a venous thromboembolism in their legs or lungs. Patients were seen as high risk if they had a SAVED score of 2 or higher or an IMPEDE score of 4 or higher.

Twenty-one percent of patients (n=39) had a blood clot after spinal surgery. Of the patients, about 35 had VTEs that included deep vein thrombosis and pulmonary embolism, and four experienced clots in arteries. It took an average of 7.7 months after treatment began for a clot to develop.

When the treatment began, 74% of patients received aspirin, 15% were taking anticoagulants, and 11% had no preventive treatment. Of the patients with clots, the majority (71%) were prescribed aspirin. Most of the patients had no form of protection, and just a few were prescribed anticoagulants.

Patients who were at higher risk experienced clots more frequently (23.8%) than those who were at lower risk (16.7%), but the difference was not considered statistically significant. Rapid clot formation occurred more frequently in patients considered high risk. Anticoagulant therapy was associated with less clotting in high-risk patients (11%) compared with those who took only aspirin (27%), which may mean that anticoagulants are more effective for this group.

The results showed that clots were still a significant issue in all groups, with 19.1% taking aspirin, 19.2% taking anticoagulants, and 30% not taking any preventatives.

Overall, the study found that patients predicted to have a low risk for clot formation still had a high number of clots, and this was most noticeable after 6 months of treatment. Taking aspirin by itself may not be enough to prevent blood clots for patients with myeloma. Taking a closer look at risks and increasing the use of preventive measures might be useful.