Network-Based Analysis of Health-Related Quality of Life Following Surgery for Degenerative Cervical Myelopathy.

Abstract

Health-related quality of life (HRQoL) is a key outcome in degenerative cervical myelopathy (DCM), however, conventional score-based analyses do not capture the complex interdependencies among HRQoL domains or how these relationships change following surgery. To characterize the structural organization of HRQoL in patients with DCM using a network-based approach. Prospective multicenter observational study. A total of 849 patients undergoing surgical treatment for DCM at 10 high-volume spine centers in Japan. HRQoL was assessed using the Short Form-36 (SF-36), including eight domain scores and summary component scores, measured at baseline, one to two years postoperatively. Gaussian graphical models were used to construct item-level and domain-level HRQoL networks from preoperative and postoperative SF-36 data. Network comparison tests assessed changes in network structure, global strength, and individual edge weights following surgery. Centrality was quantified using strength and expected influence. Subgroup analyses were performed based on postoperative Japanese Orthopaedic Association (JOA) score responsiveness. Network structure differed significantly between preoperative and postoperative phases at the domain level, whereas global network strength remained unchanged, indicating a reconfiguration of HRQoL relationships rather than uniform strengthening. Role physical (RP) emerged as the most central domain preoperatively and demonstrated a further increase in centrality after surgery. In both subgroups, RP remained highly central after surgery, whereas non-responders additionally exhibited an increase in the centrality of general health. Surgical treatment for DCM is associated with a reorganization of the HRQoL network structure rather than a global increase in connectivity. The increasing centrality of RP highlights its potential role in postoperative HRQoL recovery. Network analysis provides a novel framework for understanding HRQoL in DCM and underscores the importance of postoperative strategies aimed at restoring daily role functioning to maximize patient-centered outcomes.