Objective: To examine the longterm effect of etanercept (ETN) therapy on health-related quality of life (HRQOL) and utility in patients with ankylosing spondylitis.
Methods: Patients completing a 24-week placebo-controlled trial were continued on ETN in a 72-week open-label extension study. Short Form-36 (SF-36), EuroQOL-5D (EQ-5D), and EuroQOL visual analog scale (EQ-VAS) scores were collected at open-label baseline and every 12 weeks thereafter. Mental and physical component scores (MCS and PCS) of the SF-36, EQ-5D and SF-6D utility scores, and quality-adjusted life-years (QALY) were calculated.
Results: 257 patients [129 previous placebo (PLA) and 128 ETN recipients] enrolled in this open-label extension study, and 85% completed the 72-week followup. PCS, EQ-5D and SF-6D utilities, and EQ-VAS were significantly lower at open-label baseline in the previous PLA group (PLA/ETN group) than in the previous ETN group (ETN/ETN group; all p < 0.001). At week 12, PCS and MCS, EQ-5D and SF-6D utility scores, and EQ-VAS were similar in the PLA/ETN and ETN/ETN groups. As expected, mean change in EQ-5D in the PLA/ETN group was significantly greater than that for SF-6D (0.18 vs 0.06; p < 0.0001). HRQOL and utility improvements were maintained in both groups for up to 72 weeks. The average 72-week QALY gain per person in the PLA/ETN group was 0.24 and 0.10 for EQ-5D and SF-6D, respectively.
Conclusion: Patients continuing ETN therapy sustained HRQOL and utility improvements attained during the original PLA-controlled trial. Patients previously taking PLA showed rapid and sustained improvements in HRQOL and utility and substantial QALY gain with ETN therapy.