SAN DIEGO (FRONTLINE MEDICAL NEWS) – Among children with types 1 and 2 von Willebrand disease (VWD), a higher proportion of boys than girls reported ever having a bleeding episode and using more treatment products. But the trend did not continue among children with type 3 disease.

Those are some of the key findings from a never-before-published analysis of surveillance data from the Centers for Disease Control and Prevention presented by Karon Abe, PhD, during a poster session at the biennial summit of the Thrombosis & Hemostasis Societies of North America.

Dr. Abe, chief of the epidemiology and surveillance branch in the division of blood disorders at the CDC’s National Center on Birth Defects and Developmental Disabilities, and her associates set out to assess the differences in bleeding characteristics among preadolescent boys and girls by VWD type.

The researchers retrieved data from the UDC (Universal Data Collection System), a federally funded surveillance system of people with hemophilia and other bleeding disorders treated at 130 U.S. Hemophilia Treatment Centers (HTCs) during 1998-2011. Although UDC data collection ended in 2011, a current CDC bleeding surveillance project called Community Counts continues and expands on the work of the UDC.

Between 1998 and 2011, data were collected on 2,413 children with VWD aged 2-12 years. Of these, 2,070 had type 1, 224 had type 2, and 119 had type 3 VWD. The researchers used chi-square analysis and Wilcoxon rank sum tests to assess differences in bleeding characteristics by sex and by type of VWD. Next, they used a multivariate regression model to examine the association between demographic and clinical characteristics and a history of ever having had a bleeding episode among type 1 VWD patients.

Nearly two-thirds of children (65%) were non-Hispanic, 17% were Hispanic, 8% were black, and the remainder were from other ethnicities. In addition, 40% of the children had no family history of a bleeding disorder.

The median age of first bleed was lower among children with type 3 VWD, compared with other VWD types, and was lower among boys than girls with type 1 VWD (36 months vs. 48 months, respectively; P less than .001) and type 3 VWD (9 months vs. 12 months; P = .04), Dr. Abe reported.

A higher proportion of boys than girls reported ever having a bleeding episode among children with type 1 VWD (78% vs. 73%; P = .01) and type 2 VWD (90% vs. 75%; P = .01), but not among children with type 3 VWD (97% vs. 96%; P = .77).

A higher prevalence of treatment-product use was reported among children with type 3 VWD, compared with those with the other VWD types (a mean of 95% vs. 79% and 71% among types 2 and 1, respectively). A significantly higher prevalence of the use of treatment product was seen among boys than girls with type 1 VWD (73% vs. 68%, P = .03) and type 2 VWD (87% vs. 72%, P =.01), but not type 3 VWD (94% vs. 96%, P = .87).

The most common sites of the first bleed among all patients regardless of gender or VWD type were epistaxis and oral cavity bleeding.

“To our surprise, the boys were showing more bleeding and were receiving more product than the females,” Dr. Abe said in an interview. “This is a fairly large population.”

Multivariate regression analysis revealed independent associations between the following patient characteristics and ever having a bleed among children with type 1 VWD: male gender (adjusted odds ratio, 1.23); being aged 7-9 years at registration, compared with being aged 2-6 years (aOR, 1.5); being black (aOR, 1.7); being Asian, Native Hawaiian or Pacific Islander (aOR, 2.4), being Hispanic (aOR, 2.8), and being some other race/ethnicity (aOR, 1.8). However, family history of a bleeding disorder was protective (aOR, 0.721).

Dr. Abe said she hopes that the findings will raise awareness and help physicians to educate families about bleeding symptoms and intervene to treat bleeding episodes appropriately. She and her associates are planning to compare the data with Community Counts, “so it’s more up to date,” she said.

Dr. Abe reported having no financial disclosures.

SOURCE: Abe K et al. THSNA 2018, Poster 145 .