Long-term quality of life and work status after high-dose spinal cord stimulation in patients with failed back surgery syndrome: a secondary analysis of real-world data

Objective: In recent years, the use of high-dose spinal cord stimulation (HD-SCS) as a treatment option for patients with failed back surgery syndrome (FBSS) has drastically increased. However, to the authors' knowledge a thorough evaluation of health-related quality of life (HRQOL) and work status in these patients has not yet been performed. Moreover, it is unclear whether patients who are treated with HD-SCS can regain the same levels of HRQOL as the general population. Therefore, the aims of this study were to compare the HRQOL of patients who receive HD-SCS to HRQOL values in an age- and sex-adjusted population without FBSS and to evaluate work status in patients who are receiving HD-SCS.

Methods: HRQOL, measured with the 3-level EQ-5D (EQ-5D-3L), and work status were evaluated in 185 FBSS patients at baseline (i.e., before SCS) and at 1, 3, and 12 months of treatment with HD-SCS. Difference scores in utility values between patients and an age- and sex-adjusted normal population were calculated. One-sample Wilcoxon tests were used to assess the EQ-5D-3L difference scores. Mixed models were used to evaluate the evolution over time in EQ-5D-3L utility scores and EQ-5D visual analog scale (VAS) scores in patients and matched controls. Quality-adjusted life-years (QALYs) were calculated using the area under the curve method.

Results: An overall significant increase in EQ-5D-3L utility scores and EQ-5D VAS scores was found over time in the patient group. Wilcoxon tests indicated that the difference scores in utility values between patients and the normal population were significantly different from zero at all time points. The median incremental QALY after 12 months of HD-SCS was 0.228 (Q1-Q3: 0.005-0.487) in comparison to continued conservative treatment. At 12 months, 13.75% of patients resumed work.

Conclusions: HD-SCS may lead to significantly increased HRQOL at 12 months in patients with FBSS. Despite the increase, reaching the HRQOL level of matched controls was not achieved. Only a limited number of patients were able to return to work. This finding indicates that specialized programs to enhance return to work may be beneficial for patients undergoing SCS.