Better adherence to prescribed treatment regimen is related to less chronic pain among adolescents and young adults with moderate or severe haemophilia.

Little data exist, especially for adolescent and young adult (AYA) persons with haemophilia (PWH), about the relationship between adherence to prescribed treatment regimen and chronic pain. We examined this relationship among PWH (moderate or severe) aged 13-25 via cross-sectional survey. Adherence was assessed using the Validated Hemophilia Regimen Treatment Adherence Scale (VERITAS)-Pro and VERITAS-PRN for prophylactic and on-demand participants respectively. VERITAS scores range from 24 (most adherent) to 120 (least adherent). Chronic pain was measured using the FPS-R and was dichotomized as high for FPS-R scores ≥4 and low for <4. Logistic regression models were constructed to assess factors associated with having high (vs. low) chronic pain. Of 80 AYA respondents (79 men), most had severe disease (91%), infused prophylactically (86%) and had haemophilia A (91%). Fifty-one per cent were aged 13-17 and most were white (76%), non-Hispanic (88%) and never married (93%). Chronic pain was reported as high for 35% of respondents. Mean VERITAS-Pro scores for those with high and low chronic pain were 53.6 ± 12.3 vs. 47.4 ± 12.9, P = 0.05. VERITAS-PRN scores were similar across chronic pain status. Logistic regression revealed that for each 10-point reduction (i.e. increase in adherence) in the combined VERITAS (Pro and PRN) and VERITAS-Pro scores there was a 35% (OR = 0.65; 95% CI = 0.44, 0.96; P = 0.03) and 39% (OR = 0.61; 95%CI = 0.39, 0.96; P = 0.03) reduction in odds of having high chronic pain respectively. Among AYA PWHs, better adherence was associated with significantly lower odds of having high chronic pain. Moreover, non-whites were >4 times as likely as whites to report high chronic pain.