Improvement of sleep quality after treatment in patients with lumbar spinal stenosis: a prospective comparative study between conservative versus surgical treatment

Despite the importance of sleep and the evidence on its relationship with various chronic diseases, quality of sleep is not considered in patients with lumbar spinal stenosis (LSS). This prospective comparative study aimed to investigate the changes in sleep disturbance after treatment in patients with LSS. Patients with LSS and sleep disturbance (n=201; 147 conservatively treated and 54 patients with surgical treatment) were included. The Pittsburgh sleep quality index (PSQI) was used to evaluate sleep quality. Propensity score matching was used to attenuate the potential bias. Clinical outcome of surgery, as determined by the Oswestry disability index, and the PSQI was compared between the two groups at 6 weeks, 3 months, and 6 months after enrollment. Multivariate logistic analysis was performed to adjust for possible confounders within the matched cohorts. Among the 201 patients, 96 (47.7%) patients were finally matched (48 patients in each group). Sleep quality was initially improved after treatment, regardless of the treatment method. Sleep quality in the surgical group was improved by 6 weeks after surgery and consistently improved during the 6-month follow-up period, despite less use of pain killer. Conversely, the improvement in sleep quality at 6-weeks following conservative treatment was not maintained during the follow-up, although the treatment outcome for LSS measured by ODI was continuously improved. After multivariate logistic regression analysis within propensity score matched cohorts, surgical treatment had a significantly greater chance to improve sleep quality compared to conservative treatment. The failure of sleep improvement in conservative group was significantly associated with depression presented by worse score in Hamilton depression rating scale, and more severe degree of foraminal-type stenosis, which should be carefully considered for conservative treatment of LSS patients with sleep disturbance.