Aims: Patients with cancer are at high risk of venous thromboembolism (VTE), which entails a high economic burden. The risk of cancer-associated VTE can be assessed using the Khorana score (KS), a validated VTE risk prediction algorithm. This study compared healthcare costs associated with different KS in a population of patients newly diagnosed with cancer.
Methods: The Optum Clinformatics DataMart database (01/01/2012-09/30/2017) was used to select adult patients with ≥1 hospitalization or ≥2 outpatient claims with a cancer diagnosis (index date) initiated on systemic therapy or radiation therapy. Patients were classified in mutually exclusive cohorts based on KS (i.e. KS = 0, 1, 2 or ≥3). The observation period spanned from index to the earliest among the end of data availability, death, end of insurance coverage, or 12 months.
Results: In total 6,194 patients (KS = 0: 2,488; KS = 1: 2,125; KS = 2: 1,074; KS ≥ 3: 507) were included. On average, patients were aged 68 years, 48-52% were female, and the Quan-Charlson comorbidity index ranged between 1.1 and 1.4. Over the observation period, all-cause total healthcare costs per patient per month (PPPM) were $8,826 (KS = 0), $11,598 (KS = 1), $14,028 (KS = 2), and $16,211 (KS ≥ 3). Using the KS = 0 cohort as a reference, adjusted PPPM costs were $2,506, $4,775, and $6,452 higher in the KS = 1, KS = 2, and KS ≥ 3 cohorts, respectively. Hospitalization and outpatient costs were the main drivers of these differences. Similar results were found for VTE-related costs, which represented 4-11% of the total all-cause cost difference between KS cohorts.
Limitations: Residual confounders; results may not be generalized to patients with other insurance plans or those who received treatments other than systemic therapy or radiation therapy.
Conclusions: This real-world analysis found that cancer patients at higher risk of VTE (based on KS) incurred significantly greater all-cause and VTE-related healthcare costs compared with cancer patients at lower risk of VTE.
Keywords: I; I1; I10; I19; Khorana score; Venous thromboembolism; cancer; cancer-associated VTE; healthcare costs.