A Comparison of Different Venous Thromboembolism Prediction Scoring Systems in Newly Diagnosed Multiple Myeloma in an Arabic Population

Background

The risk of venous thromboembolism (VTE) is high in patients with multiple myeloma (MM). Various predictive VTE- risk scoring systems (RSS) are used in practice, including IMWG, IMPEDE, SAVED, and PRISM (Palumbo et al., Sanfilippo et al., Li et al., and Chakraborty et al., respectively). However, factors such as thromboprophylaxis regimens and differences in local clinical practice may lead to suboptimal VTE prevention. This study aimed to evaluate the ability of different RSS to predict VTE in Arab patients with newly diagnosed MM.

Methods

This retrospective cohort study was conducted at the National Center for Cancer Care and Research in Qatar. All patients with newly diagnosed MM during the period 2020-2023 were included. The patients' electronic medical records were reviewed. Patients with relapsed or smoldering MM and patients already on therapeutic anticoagulation were excluded. Data collected included details of VTE risk factors adapted from the IMWG, SAVED, IMPEDE, and PRISM RSS. The type of VTE prophylaxis and radiology-confirmed VTE events were also recorded, along with data on ethnicity. The VTE- RSS were assessed for their ability to predict VTE in this population within a year from diagnosis. Ethnically Arab patients were compared with non-Arabs patients. Statistical significance was set at p-value ≤ 0.05.

Results

A total of 82 patients were included in this study. The median age of the patients was 55 years [range, 31- 85]; 73% of patients were male, 45% were of Arab ethnicity, and 50% of patients had stage III disease, according to the International Staging System. The mean body mass index (BMI) was 26.8 kg/m², and 61% of the patients had a BMI ≥ 25 kg/m². Most patients (81.9%) received immunomodulators (IMiDs). The most common regimen was DARA-VRd (daratumumab, bortezomib, lenalidomide, dexamethasone). There were significant differences in the number of patients identified as high risk between the VTE- RSS, specifically 43.9%, 35.3%, 25%, and 15.8% as defined by the IMPEDE, IMWG, SAVED, and PRISM scores, respectively. The majority of patients (97.5%) received thromboprophylaxis, 70.7% were given aspirin (ASA) and 26.8% received rivaroxaban (RIV). Of the ASA recipients, 44.8% were eligible for intermediate/high-risk VTE prophylaxis. The most common reasons for ASA use included contraindications to anticoagulation and clinical judgement.

Some risk factors (erythropoietin use, fractures, immobility, median age) and VTE risk scores were similar between Arabs and non-Arabs. However, Arabs had a statistically higher mean BMI compared to non-Arabs (29.61 versus 24.5 (p = 0.002)). In fact, the number of Arabs with a BMI ≥ 25 kg/m² (n_(Arabs)=31 vs n_(non-Arabs)=19) and a BMI ≥ 30 kg/m² (n_(Arabs)=19 vs. n_(non-Arabs)=3) was significantly higher than that of non-Arabs (p=0.001 for both). In addition, there was a significant difference between the two groups in the IMWG-defined comorbidities that affect VTE (n_(Arabs)=31 vs. n_(non-Arabs)=22 p=0.003), particularly with CKD (n_(Arabs)=9 vs. n_(non-Arabs)=3, p= 0.032) and diabetes (n_(Arabs)=19 vs. n_(non-Arabs)=10, p =0.009).

Eight patients (9.8%) developed non-fatal VTE events within a year of diagnosis (three Arabs and five non-Arabs). The median time from diagnosis to VTE incidence was 165 days [range 150 - 280]. All patients were on prophylaxis with ASA (n=5) or RIV (n=3). The three patients who were on RIV developed central venous catheter thrombosis following insertion. Only one patient was classified as intermediate/high risk but was receiving ASA. No association was identified between VTE incidence and MM stage, β2 microglobulin level, immunoglobulin subtype, or cytogenetics (13q del; n=3). None of the RSS were able to predict VTE (PRISM, p = 0.16), SAVED (p =0.12), IMPEDE (p = 0.48), and IMWG (p = 0.34).

Conclusion

This study is the first to compare four different VTE- RSS in newly diagnosed Arab patients with MM. The incidence of VTE in this population (9.8%) was comparable to that in the literature. Arabs had a higher BMI, more kidney disease and more diabetes. There were significant differences in the number of patients classified as high risk for VTE by each scoring system. None of the available RSS predicted the development of VTE among Arab patients. Therefore, a study with a larger myeloma population and a longer follow up period is needed to design and validate VTE-RSS that are better tailored to this patient population.

No relevant conflicts of interest to declare.