Adherence and a Potential Trade-Off Currently Faced in Optimizing Hemophilia Treatment

INTRODUCTION

Severe hemophilia, i.e., <1% normal FVIII level (A) or FIX level (B), are congenital bleeding disorders characterized by uncontrolled bleeding. The clinical benefits of prophylactic FVIII/IX replacement therapy are well understood, but require adherence to a schedule of routine infusions. Optimal adherence is associated with better joint outcomes and lower rates of chronic pain. Nonetheless a lack of patient-reported data has to date limited our understanding of the patient burden associated with adherence to treatment, and the relationship between adherence and the ability to work, among people living with hemophilia in the US. Data from the Bridging Hemophilia B Experiences, Results and Opportunities into Solutions (B-HERO-S) study reported a high proportion of adults with hemophilia B receiving routine infusions (at least one infusion per month), showing a negative impact on their ability to work, and people receiving routine infusions were more likely than people treated on-demand to report an inability to work in most situations.

The ability of people living with hemophilia to participate in the labor force, without barriers to job choice or working hours, is a key outcome in the drive to achieve health equity. The objective of the analysis is to examine the relationship between adherence and the labor force participation of people with severe hemophilia in the US.

METHODS

This analysis draws data from a patient-reported study, the ‘Cost of Severe Hemophilia Across the US: A Socioeconomic Survey’ (CHESS US+). Conducted in 2019, the CHESS US+ study is a cross-sectional patient-centered study of adults with severe hemophilia in the US. A patient-completed questionnaire collected data on clinical, economic, and humanistic outcomes, for a 12-month retrospective period.

This analysis examines labor force participation and employment status (full-time, part-time, unemployed, retired) and chronic pain categorized by ‘none’, low-level (‘1-5’), and high-level (‘6-10’).

The analysis was stratified by adherence to treatment, self-reported on a 1-10 scale, from “not at all” to “fully”, categorized into low (1-6), moderate (7-9) and full (10) adherence. Results are presented as mean (standard deviation) or N (%).

RESULTS

The analysis comprised 356 people with severe hemophilia A (73%) and B (27%) who participated in CHESS US+ study.

In Table 1, the baseline characteristics of the study population are stratified by full adherence (N = 119), moderate adherence (N=134) and low adherence (N=103).

Having no chronic pain was most prevalent in the full adherence group (37.7%), compared to moderate (8.3%) or low (13.9%) adherence cohorts. Chronic pain, both low- and high-levels were least prevalent among people with full adherence. Moreover, people with low adherence were disproportionately more likely to have high-levels of chronic pain relative to moderate adherence or full adherence (Table 1).

Unemployment, however, was highest in full adherence (21.1%), and people with full adherence were also least likely to be in full-time employment (42%). The full-time employment rate decreased as adherence declined from full to moderate (Table 1), and was comparable in people with low adherence (57.3%) or moderate adherence (54.5%).

CONCLUSIONS

This analysis of CHESS US+ examined the complex relationship between labor market outcomes and adherence to treatment, among adults with severe hemophilia in the US. Adherence was associated with lower rates of chronic pain, representing the importance of achieving an optimal treatment strategy. Nonetheless, patients achieving optimal adherence were less likely to be in full-time employment, and more likely to be part-time or unemployed, comparatively.

Together, these data characterize a trade-off in clinical outcomes versus workforce participation, and suggest that the goal of achieving health equity may currently still be unmet.