P-140: Risk and incidence of venous thromboembolism in newly diagnosed Multiple Myeloma patients

Introduction: Venous thromboembolism(VTE) is a rare but major complication seen in patients with MM. Besides varied incidences across different races, different disease burdens and therapies impact the incidence of the same. There is scarcity of data in Indian patients. In this analysis, we evaluated the prevalence of baseline predisposition factors for VTE, risk scores and outcomes in a large cohort of newly diagnosed MM (NDMM).

Methods: We retrospectively analyzed data from patients with NDMM between July 2022 to October 2023. Data was extracted from electronic health records, focusing on baseline risk factors for VTE, anti-myeloma therapy & VTE prophylaxis used and outcomes. VTE risk scores for each patient was calculated using the IMPEDE VTE and SAVED scores. Statistical analysis was done using SPSS V23.

Results: The cohort was of 184 patients with sex ratio being 2.02(male/female) whose median age was 55 years(range 30-85). Hypertension was the most common comorbidity seen in 34.2 % of patients followed by diabetes mellitus in 15.2%. 20.7% patients were categorized as ISS stage I, 25% as stage II & 49.5% as ISS stage III. High risk cytogenetics were found in 19(10.3%) patients. VRd was the most commonly used induction regime (86.8%) of patients. Immunomodulators (e.g. lenalidomide, thalidomide, pomalidomide) were used in 76.7 % of patients out of which lenalidomide and thalidomide were given in 84.6 % & 3.2 % respectively. The dexamethasone used in these regimens was unanimously low dose defined as less than 160 mg per cycle(40 mg/dose). All patients received aspirin 75 mg as VTE prophylaxis. According to the IMPEDE-VTE score, 1 patient was high risk, 14 patients were intermediate risk and 164 patients were low risk. Similarly, 163 patients were stratified as low risk and 9 patients as high risk according to SAVED score. Overall the cohort was at Low risk according to both scores.Out of the 184 patients, only 3 patients - 1.63 % developed a single episode of VTE each during the duration of study. All the three patients had Lower Limb Deep Vein thrombosis episode within 6 months on initiation of treatment. No mortality was seen due to the thrombotic event. Among the patients who developed thrombotic events, 2 patients were having intermediate risk & one patient in low risk(0.61%) as per IMPEDE VTE score. Compared to data of the cohort which proposed this score, 15.2 % of patients had VTE episodes among high risk, 8.3 % in intermediate risk and 3.3% in low risk patients. In the sample for SAVED score, 1 high risk patient & 2 low risk patients developed a VTE episode. Opposed to this, 12% of high risk patients(n=686) and 7% of low risk(n=1711) developed VTE in the sample for SAVED score.

Conclusions: In summary, our cohort had overall a low risk as well as low incidence for developing a VTE as compared to Western population. The risk scores had little utility given that most events occurred in low or intermediate risk rather than high risk score groups.