HTC Population Profile- March 2023

Technical notes

The HTC Population Profile (HTC PP) is a set of 12 data items collected on patients with bleeding disorders or venous thromboembolism (VTE). These patients receive care at hemophilia treatment centers (HTCs) that are part of the US Hemophilia Treatment Center Network (USHTCN), a network of 141 HTCs located throughout the United States and its territories. HTCs practice a model of care delivery called comprehensive (integrated) care. This care includes specialized prevention, diagnostic, and treatment programs. It also includes family-centered education, research, and support services for patients and families living with bleeding disorders.

Congress provides support to HTCs through the Health Resources and Services Administration and the Centers for Disease Control and Prevention (CDC). CDC funds Community Counts, a project conducted in collaboration with the American Thrombosis & Hemostasis Network and the USHTCN that monitors the complications of bleeding disorders. HTCs that participate in Community Counts collect data on common health issues, medical complications, and causes of death. Community Counts has three components:

• The HTC PP, which gathers basic information on all people with bleeding disorders or blood clots who receive care at HTCs;
• The Registry for Bleeding Disorders Surveillance, which gathers more detailed information on a subset of HTC PP participants with bleeding disorders who volunteer to have their information collected; and
• Mortality reporting, which tracks the characteristics, diagnoses, and causes of death of HTC patients with bleeding disorders who have died.

Data for the HTC PP component of Community Counts are collected as a de-identified¹ data set that is compliant with the Health Insurance Portability and Accountability Act (HIPAA). Authorization from patients for data collection is sought according to the institutional policies of the participating HTCs.

HTCs report on patients 89 years of age or younger who receive care either in person or by telemedicine. The 12 items collected for the HTC PP are

1. Year of birth
2. Sex²
3. Ethnicity
4. Race
5. 3-digit ZIP code of residence
6. Insurance status
7. Primary bleeding disorder diagnosis
8. Baseline factor activity³
9. Von Willebrand factor activity (vWF:RCof)
10. Von Willebrand factor antigen level (vWF:Ag)
11. Hepatitis C (HCV) infection status
12. Human immunodeficiency virus (HIV) infection status.

The data are collected on a calendar-year basis. Most data for a given year are reported by February of the following year, but some records may be received later.

In the HTC PP, only one bleeding disorder diagnosis can be reported for each patient at their annual HTC PP submission. HTCs were given the following guidance for reporting diagnosis for patients with more than one bleeding disorder diagnosis:

• The diagnosis for patients who have hemophilia plus another bleeding disorder is reported as hemophilia (factor VIII [8] or factor IX [9], as appropriate).
• The diagnosis for patients who have both factor VIII (8) and factor IX (9) deficiency is reported as whichever deficiency is more severe (has the lower baseline factor level); if equally severe, the diagnosis is reported as factor VIII (8).
• The diagnosis for patients who have von Willebrand disease VWD plus another bleeding disorder is reported as VWD (unless the other disorder is hemophilia, in which case they are reported as hemophilia).
• The diagnosis for patients who have more than one clotting factor deficiency (other than hemophilia) is reported as whichever deficiency has the lowest baseline factor level.
• The diagnosis for patients who have a clotting factor deficiency and a platelet disorder or a connective tissue disorder is reported as the clotting factor disorder.
• The diagnosis for patients who have a platelet disorder and a connective tissue disorder is reported as the platelet disorder.
• The diagnosis for patients who have a bleeding disorder and a VTE is reported as the bleeding disorder.

The HTCs began collecting data for the HTC PP in 2012. As of March 31, 2023, 146 individual HTCs have contributed data over time; 110 HTCs provided data for all 10 years (2012–2023). The data in these reports are subject to revision.

¹ De-identified means that the person’s identity cannot be connected with the information because personal identifiers, such as name, address, and birthdate, have been removed from the data file.

² Sex is displayed as the sex assigned to the patient at birth. From January 1, 2012 to August 9, 2020, transgender was a response option for patient sex. Transgender patients have been included in the counts of male and female according to the sex assigned to them at birth because hemophilia and von Willebrand disease, the most common congenital bleeding disorders, affect the sexes differently. On August 10, 2020, this question changed to ask for sex assigned at birth and the response options are male, female, and intersex. The number of intersex patients is too small to report by year or other characteristics; therefore, data from these patients has been excluded to protect patient confidentiality and to avoid complementary suppression (the suppression of additional cells to prevent calculation of these counts by subtraction) of the male or female groups.

³ Baseline factor activity is a measure of the amount of functioning clotting factor that is present in the blood before infusion of the clotting factor treatment product to boost the amount.