Effects of Psychiatric Factors on Patient-Reported Outcomes after Surgical Correction of Lumbar Degenerative Kyphosis

STUDY DESIGN: A prospective study. PURPOSE: To identify associations between psychiatric factors and patient-reported outcomes after corrective surgery in patients with lumbar degenerative kyphosis (LDK). OVERVIEW OF LITERATURE: Thus far, to the best of our knowledge, patient factors that may help predict patient-reported outcomes after corrective surgery for LDK have not been studied. METHODS: We prospectively investigated 46 patients with LDK who underwent surgical correction with a minimum follow-up of 2 years. Demographic data were collected. Short form-36, mental component scores (MCS), physical component scores (PCS), Scoliosis Research Society-22 (SRS-22) scores, and Roland-Morris Disability Questionnaire (RMDQ) scores were determined before the surgery and after 2 years of follow-up. Psychiatric conditions were preoperatively evaluated using the Zung depression scale (ZDS) and Zung anxiety scale (ZAS). Patients were divided into two groups (with or without psychiatric issues), according to baseline ZDS and ZAS scores. RESULTS: Patients included 43 women and 3 men. Twelve patients were deemed to have psychiatric problems (P group) and 34 patients had no psychiatric problems (NP group). No significant intergroup differences were found in MCS, PCS, SRS-22, and RMDQ scores preoperatively. However, at the 2-year follow-up, a significant intergroup difference was observed between PCS and RMDQ scores. Multiple regression analysis revealed that only the presence of a preoperative psychiatric problem can predict PCS and RMDQ scores. Other factors, such as, gender, age, body mass index, bone mineral density, osteotomy site, number of fusion segments, and instrumented levels did not affect PCS or RMDQ scores. CONCLUSIONS: The presence of a psychiatric factor may be an important risk factor underlying poor physical and pain scores after corrective surgery in patients with LDK. The findings presented here suggest that psychiatric factors should be evaluated prior to surgery for determining the risk of a poor outcome.