Predictors for quality of life, pain and functional outcomes after surgical treatment of metastatic disease in the spine

Background: While predictors for postoperative survival in spine tumour patients have been identified, there is limited evidence for predictors of postoperative Quality of Life (QoL), pain and functional outcome.Methods: One hundred and fifty-three consecutive patients, who had undergone surgery for symptomatic spinal metastases between June 2016 and April 2019, were interviewed preoperatively and during follow-ups at three, six and 12 months using the EQ-5D-3L, COMI, and ODI questionnaires. Differences in means exceeding the specific Minimal Clinically Important Difference (MCID) values were considered clinically significant.Results: Thirty-three percent of the patients were reported dead after 12 months. Only one metastasis compared to multiple metastases has 7.9 the Odds for an improved EQ-5D-3L score at three months. No neoadjuvant metastatic irradiation has 6.8 the Odds for the improvement at that time against performed radiation. A pre-operative ODI score between 50.1 and 100 has 22.0 times the odds compared to the range from 0 to 50 for an improved EQ-5D-3L after three months, and 12.5 times the odds in favour of improved COMI after three months, and 13.6 times the odds for improvement of ODI at the three-month follow-up. A preoperative COMI score ranging from 5.0 to 10 has 21 times the odds of a COMI between 0 and 5 for an improved EQ-5D-3L score and 11 times the odds for an improved ODI after 12 months. Other predictors showed no statistically significant improvement.Conclusion: An improvement in QoL, pain and spinal function after 12 months can be predicted by a subjective preoperative poor health condition. Impaired spinal function before surgery, a singular metastasis and no previous irradiation is predictive of improved spinal function and quality of life three months after surgery.