Long-term outcomes and age-dependent recovery trajectories following short-term spinal cord stimulation in patients with disorders of consciousness

Abstract

Objective To evaluate long-term changes in consciousness and age-related recovery patterns in patients with prolonged disorders of consciousness (pDoC) following spinal cord stimulation (stSCS), and to explore whether early postoperative neurological improvement is associated with long-term outcomes. Methods This retrospective study included 30 patients with pDoC who underwent stSCS and were followed for 24 months. Consciousness was assessed using the Coma Recovery Scale–Revised (CRS-R) at baseline, 3 days, 14 days, 12 months, and 24 months. Patients were stratified into younger (≤50 years) and older (>50 years) groups. Longitudinal changes in CRS-R scores were analyzed using linear mixed-effects models, and linear regression was performed to evaluate the association between early neurological improvement at 14 days and 12-month outcomes. Results CRS-R scores progressively increased during the 24-month follow-up, with significantly higher scores at 12 months (10.47 ± 6.52) and 24 months (11.84 ± 6.38) compared with baseline (6.17 ± 2.67, both p < 0.001). Analysis of CRS-R changes from baseline suggested different recovery patterns between age groups. Younger patients showed earlier within-group improvement, although overall recovery trajectories and long-term outcomes were comparable between age groups. However, no significant differences in overall CRS-R improvement were observed between the two groups. The distribution of clinical consciousness states was also comparable between groups during follow-up. Early improvement at 14 days was significantly associated with 12-month CRS-R scores in both the Younger Group (R2 = 0.536, p = 0.0019) and the Older Group (R2 = 0.810, p < 0.0001). Conclusion Patients with pDoC showed sustained CRS-R improvement after stSCS during long-term follow-up. Age appeared to influence the pattern of recovery, with younger patients showing earlier improvement, although overall long-term outcomes were comparable between age groups. Early improvement was associated with better long-term outcomes, suggesting potential prognostic value. The specific contribution of stSCS requires further validation in prospective controlled studies.