title: Predictors of quality of life among adolescents and young adults with a bleeding disorder.
abstract: BACKGROUND
  Health-related quality of life (HRQoL) in adolescents and young adults with bleeding disorders is under-researched. We aimed to describe factors related to HRQoL in adolescents and young adults with hemophilia A or B or von Willebrand disease.
  
  
  METHODS
  A convenience sample of volunteers aged 13 to 25 years with hemophilia or von Willebrand disease completed a cross-sectional survey that assessed Physical (PCS) and Mental (MCS) Component Summary scores on the SF-36 questionnaire. Quantile regression models were used to assess factors associated with HRQoL.
  
  
  RESULTS
  Of 108 respondents, 79, 7, and 14% had hemophilia A, hemophilia B, and von Willebrand disease, respectively. Most had severe disease (71%), had never developed an inhibitor (65%), and were treated prophylactically (68%). Half of patients were aged 13 to 17 years and most were white (80%) and non-Hispanic (89%). Chronic pain was reported as moderate to severe by 31% of respondents. Median PCS and MCS were 81.3 and 75.5, respectively. Quantile regression showed that the median PCS for women (61% with von Willebrand disease) was 13.1 (95% CI: 2.4, 23.8; p = 0.02) points lower than men. Ever developing an inhibitor (vs never) was associated with a 13.1-point (95% CI: 4.7, 21.5; p < 0.01) PCS reduction. MCS was 10.0 points (95% CI: 0.7, 19.3; p = 0.04) higher for prophylactic infusers versus those using on-demand treatment. Compared with patients with no to mild chronic pain, those with moderate to severe chronic pain had 25.5-point (95% CI: 17.2, 33.8; p < 0.001) and 10.0-point (95% CI: 0.8, 19.2; p = 0.03) reductions in median PCS and MCS, respectively.
  
  
  CONCLUSIONS
  Efforts should be made to prevent and manage chronic pain, which was strongly related to physical and mental HRQoL, in adolescents and young adults with hemophilia and von Willebrand disease. Previous research suggests that better clotting factor adherence may be associated with less chronic pain.
authors.affiliation: Pfizer Inc, Global Innovative Pharma, 500 Arcola Rd, Collegeville, PA, 19426, USA. john.mclaughlin@pfizer.com.
authors.forename: John M
authors.initials: JM
authors.lastname: McLaughlin
authors.affiliation: University of Michigan Hemophilia Treatment Center, 1500 E. Medical Center Drive, Ann Arbor, MI, USA.
authors.forename: James E
authors.initials: JE
authors.lastname: Munn
authors.affiliation: Pfizer Inc, Global Innovative Pharma, 500 Arcola Rd, Collegeville, PA, 19426, USA.
authors.forename: Terry L
authors.initials: TL
authors.lastname: Anderson
authors.affiliation: Henry Ford Hemophilia & Thrombosis Treatment Center, 2799 W Grand Blvd, Detroit, MI, USA.|Currently: Bayer HealthCare, Whippany, NJ, USA.
authors.forename: Angela
authors.initials: A
authors.lastname: Lambing
authors.affiliation: Pfizer Inc, Global Innovative Pharma, 500 Arcola Rd, Collegeville, PA, 19426, USA.
authors.forename: Bartholomew
authors.initials: B
authors.lastname: Tortella
authors.affiliation: Northern Regional Bleeding Disorder Center, 1105 Sixth St, Traverse City, MI, USA.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Witkop
mesh_terms: D000293:Adolescent; D003430:Cross-Sectional Studies; D005260:Female; D006305:Health Status Indicators; D006467:Hemophilia A / Q000523:psychology* / Q000628:therapy; D006801:Humans; D008297:Male; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Chronic pain; Hemophilia; Pain management; Patient adherence; Prophylaxis; von Willebrand disease