Introduction: Degenerative Cervical Myelopathy (DCM) represents the most common cause of non-traumatic spinal cord impairment in adults. Surgery improves symptoms and functional status, but it is costly. As sustainability concerns in the field of healthcare rise, evidence for both health related quality of life (HRQoL) outcomes and financial expenditures are needed. The aim of this study is to estimate the lifetime incremental cost utility ratio (ICUR) of surgery for DCM.
Methods: All patients undergoing surgery for DCM at a single center between 2005 and 2011 who were enrolled in either the AOSpine CSM-North America or CSM-International studies were eligible. HRQoL was measured at baseline and then 6, 12 and 24-months following surgery using the Short Form-6D score. Resource expenditures were calculated on an individual level, from the hospital payer perspective over the 24-month follow-up period. All costs were obtained from a micro-cost database and reported in Canadian dollars; inflated to January 2015 values. ICUR estimates were obtained using a Markov state transition model. Single way deterministic sensitivity analysis and Monte Carlo probabilistic sensitivity analysis were conducted to address uncertainty.
Results: The analysis included 171 patients. Baseline HRQoL was 0.56 ± 0.14. Mean quality adjusted life-years (QALY) gained over the 24-month study period was 0.139 (95% CI: 0.109-0.170, p<0.001) and mean 2-year cost of treatment was $19,217 ± 12,404. Using the general Markov model, the estimated lifetime ICUR of surgical intervention was $11,496/QALY gained, with 97.9% of estimates falling within the World Health Organization definition of ‘very cost effective’ ($54,000 CAD). Under the application of extremely conservative model parameters for non-operative management and durability of surgical improvement, 73.4% of interventions were classified as ‘very cost-effective’.
Conclusions: Surgery for DCM is associated with a significant quality of life improvement. The intervention appears cost effective from the perspective of the hospital payer and should be supported.
Patient Care: These findings will be of relevance to healthcare practitioners and policymakers alike. The study should serve to inform policy decisions and help to optimize resource allocation in a climate of ever increasing austerity measures to curb healthcare expenditures. Moreover, this data should help guide future research efforts into the value of spinal surgery.
Learning Objectives: By the conclusion of this session, participants should be able to 1) describe the estimated value of surgery for degenerative cervical myelopathy, 2) recognize the importance of health economic assessments of surgical intervention, and 3) discuss potential ways to address uncertainty in estimation of cost-utility for spinal surgical intervention.