Interpreting important health‐related quality of life change using the Haem‐A‐QoL

Abstract

Summary The Haemophilia Quality of Life Questionnaire for Adults (Haem‐A‐QoL) measures health‐related quality of life (HRQoL) in adults with haemophilia; however, change score thresholds for identifying individuals experiencing a HRQoL benefit have not been appropriately investigated. The objective of this analysis was to derive appropriate HRQoL responder definitions (RDs) for two Haem‐A‐QoL domains that reflect key impairments, ‘Physical Health’ and ‘Sports & Leisure,’ and the Haem‐A‐QoL ‘Total Score’ using anchor‐ and distribution‐based methods. In this analysis, data from adults in A‐LONG and B‐LONG, two Phase 3 clinical studies of rFVIIIFc in haemophilia A and rFIXFc in haemophilia B, respectively, were used. The anchor‐based approach identified Haem‐A‐QoL changes corresponding to EQ‐5D item improvements between baseline and 6 months; the distribution‐based methods examined the magnitude at baseline of one‐half standard deviation and the standard error of measurement. Through triangulation, the most appropriate RDs were derived. Of the 133 A‐LONG and 73 B‐LONG subjects with baseline Haem‐A‐QoL scores, 67 and 51 subjects, respectively, completed the Haem‐A‐QoL questionnaire at both baseline and 6 months follow‐up. Triangulation of anchor‐ and distribution‐based estimates with the observed Haem‐A‐QoL change scores identified a 10‐point reduction in the ‘Physical Health’ and ‘Sports & Leisure’ domains, and a 7‐point reduction in ‘Total Score’ as the RD thresholds most indicative of HRQoL benefit. These empirically derived RDs for two key Haem‐A‐QoL domains and ‘Total Score’ are reasonable and practical thresholds for identifying subjects with notable improvements in HRQoL, and provides HRQoL RDs that can be used for further analysis and interpretation of data from haemophilia clinical trials.

The effect of emicizumab prophylaxis on health‐related outcomes in persons with haemophilia A with inhibitors: HAVEN 1 Study

“…Throughout the study, a greater proportion of participants in the emicizumab prophylaxis groups (Arms A and C) than the no prophylaxis group (Arm B) achieved an improvement from baseline exceeding responder thresholds for “Total” (−7 points) and “Physical Health” domain (−10 points) scores (Figure A,B). In the cumulative distribution plots of change from baseline to week 25 for both the “Total” and “Physical Health” domain scores, there was a clear separation between Arms A and B throughout all potential levels of change (Figure B and B).…”

“… Responder thresholds defined for “Physical Health” (−10), “Sports and Leisure” (−10) and “Total” score (−7) …”

“…This is supported by the high rate of participants achieving responder thresholds on Haem‐A‐QoL “Total” and “Physical Health” domain scores. Currently, there is no consensus on how changes in HRQoL outcomes should be interpreted, but the responder thresholds used in this study provide an estimate of notable improvements that, when combined with other findings, suggest meaningful improvements in participants’ lives . Further longitudinal assessments are needed, however, to quantify how the HRQoL changes observed with emicizumab prophylaxis correspond to real‐life improvements.…”

“…The proportion of participants achieving an improvement at week 25 larger than a previously published responder threshold was calculated for Haem‐A‐QoL “Total” score (−7), Haem‐A‐QoL “Physical Health” score (−10), EQ‐5D‐5L IUS (+0.07) and EQ‐VAS (+7) …”

The impact of haemophilia on the social status and the health‐related quality of life in adult Lebanese persons with haemophilia

“…Some studies around the world have evaluated the HRQoL of PWH using a standardized questionnaire called MOS SF‐36 (for Medical Outcome Study Short Form 36), abbreviated SF‐36 . Other studies have used other questionnaires such as the Haem‐A‐QoL to evaluate specific measures in HRQoL of adult PWH …”