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Adherence to clotting factors among persons with hemophilia A or B
Insights
Most severe hemophilia patients struggle with consistent clotting factor treatment adherence, with over two-thirds using medication less than 70% of the time. This highlights a critical gap in managing this bleeding disorder effectively.
Area of Science:
- Hematology
- Pharmacology
- Public Health
Background:
- Hemophilia is a genetic bleeding disorder requiring lifelong management with clotting factor replacement therapy.
- Adherence to prophylactic treatment is crucial for preventing bleeding episodes and long-term complications in hemophilia patients.
Purpose of the Study:
- To evaluate treatment adherence to clotting factor therapy among patients with hemophilia.
- To assess the association between adherence and clinical outcomes in hemophilia management.
Main Methods:
- Retrospective observational study of 207 hemophilia patients from 2006-2011 using integrated delivery database.
- Medication adherence assessed via prescription claims, calculating the ratio of days' supply to observed days.
- Adherence defined as ≥60% ratio for severe hemophilia patients requiring prophylactic treatment.
Main Results:
- 51% adherence in severe hemophilia patients, compared to 14% mild and 21% moderate.
- Among severe hemophilia patients, 66.2% had adherence <70% of the time.
- Joint bleeding and hospitalizations were infrequent across all severity groups.
Conclusions:
- A significant majority of severe hemophilia patients exhibit suboptimal adherence to clotting factor treatment.
- Findings underscore the need for interventions to improve treatment adherence in hemophilia care.
- Further research is warranted to identify barriers and facilitators to adherence.
Objective:
Evaluate adherence to clotting factor treatment and associated outcomes for patients with hemophilia using an integrated delivery database.
Methods:
This was a retrospective, observational study tracking patients between 2006 and 2011. Patients with diagnosis codes for hemophilia were identified. Bleeding and complication rates were annualized over the study period. Medication adherence was assessed using prescription claims for clotting factors by examining sequential time periods of 180 days for each patient's continuous enrollment. Adherence within the time period was calculated using the 'days supply' field divided by 180 days. Under the assumption that severe patients should be treated prophylactically, patients were considered adherent within the time period if the ratio of 'days supply' to observed days was 60% or greater.
Results:
A total of 207 patients (74.9 and 25.1% hemophilia A and B, respectively) met the inclusion/exclusion criteria. There were 101 (48.8%) mild, 32 (15.5%) moderate, and 74 (35.7%) severe patients with hemophilia. The percentage of time periods where adherence to clotting factors was 60% or greater was 14% (SD = 28%) for mild disease, 21% (SD = 32%) for moderate disease, and 51% (SD = 36%) for severe disease. Among patients with severe disease, 27 (36.5%) were adherent ≤ 30% of time periods, 22 (29.7%) adherent 31-70% of the time periods, and 25 (33.8%) were adherent ≥ 71% of time periods. Joint bleeding episodes and hospitalizations were uncommon events among the three groups.
Conclusions:
Among patients with severe disease, the majority (66.2%) were adherent <70% of the time.
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