The analysis emphasizes the association between vaso-occlusive crisis frequency and health care costs, which are inflated largely due to inpatient visits.
Vaso-occlusive crises (VOCs) are a common clinical manifestation of sickle cell disease (SCD) and cause pain episodes that can be debilitating. In addition to affecting patient quality of life, recurrent VOCs were associated with significantly higher health care resource utilization (HCRU) and costs for SCD patients in an analysis presented as a poster at the AMCP Nexus 2022 annual meeting.
SCD is a rare disorder characterized by the formation of abnormally shaped hemoglobin, known as sickle hemoglobin. This causes a range of complications, from acute pain episodes, acute chest syndrome, and stroke to chronic issues including end-organ damage. In the United States, the health care costs associated with the disease are estimated to be nearly $3 billion per year. The majority (57%) of those costs are related to inpatient care, 38% are associated with outpatient care, and 5% are out-of-pocket costs.
Past studies have found that VOC frequency is a significant driver of the HCRU and costs associated with SCD, but research in the subgroup of patients who experience recurrent VOCs is lacking. An economic model in a previous study estimated the lifetime costs for this subgroup of patients to be between $4.2 million and $6.2 million.
The current retrospective study used claims databases to identify patients with SCD between March 2010 and March 2019, then identified SCD-related costs using de-identified inpatient and outpatient medical costs and drug prescription data from MarketScan databases. The exploratory analysis paired each patient who experienced recurrent VOCs with up to 5 controls to provide context around SCD costs and HCRU.
A total of 36,128 patients with SCD claims were identified in the databases, including 3420 who had recurrent VOCs and met other eligibility requirements for the analysis. The mean patient age was 19.1 years, and most patients were in the Medicaid database.
Inclusion criteria included having at least 1 non-diagnostic inpatient claim of SCD or at least 2 outpatient claims within 1 year of each other, as well as experiencing at least 2 VOCs per year for 2 consecutive years. VOCs included acute chest syndrome, priapism, pain crises, and splenic sequestration. Events at least 3 days apart from one another were considered distinct. Patients also needed to have at least 2 years of continuous enrollment with medical and pharmacy benefits prior to the second VOC claim in the second year of 2 consecutive years, as well as at least 1 year of continuous enrollment after the index date.
The control group included a general population of 16,662 individuals who did not have claims for SCD or other blood disorders at any time during their MarketScan enrollment. Controls were matched to SCD patients based on age, sex, region, payer type, and follow-up duration.
Overall, patients with recurrent VOCs showed higher HCRU than matched controls. This included a higher number of inpatient admissions per patient per year (PPPY) and more emergency room (ER) visits PPPY. Patients with SCD had a mean of 2.7 inpatient admissions and 5 ER visits PPPY, versus 0.05 inpatient admissions and 0.6 ER visits in healthy controls. During the variable-length follow-up period, patients with 2 or more VOCs PPPY had higher HCRU than the overall cohort, and patients with recurrent VOCs had an average of 5 VOCs PPPY.
Total health care costs were also higher for patients with SCD with recurrent VOCs. While these patients had annual health care costs averaging $67,282 per year, matched controls averaged $4134 per year. This was largely due to inpatient medical costs. The average cost per VOC was $9868, and annual costs for patients with recurrent VOCs were $47,663 PPPY. The cost disparity is substantial over the course of patients’ lifetimes — by age 50, healthy controls are expected to accumulate approximately $229,000 in health care costs, while those with SCD and recurrent VOCs are expected to accumulate $3.8 million in health care costs. In yearly and lifetime estimates, costs were higher among patients with commercial insurance versus those with Medicaid.
While the study relied on administrative claims and only includes direct medical costs — potentially leading to underestimates of the overall cost of SCD — the findings highlight the substantial economic burden associated with recurrent VOCs in SCD. Another area of potential underestimation is the rate of VOCs, some of which may be managed at home and therefore not part of claims databases. The findings also may not be generalizable to patients without heave care coverage.
Still, the analysis emphasizes the connection between VOC frequency and health care costs, which are largely due to inpatient visits. The economic burden highlighted in the study also supports previous estimates of the costs associated with SCD and recurrent VOCs.
Udeze C, Evans K, Yang Y, et al. Economic burden of managing patients with sickle cell disease with recurrent vaso-occlusive crises in the United States. Poster presented at: AMCP Nexus; October 11-14, 2022; National Harbor, MD. Poster D10.