Introduction: Mental status can be an important determinant of physical wellbeing. Patients suffering from spinal stenosis are likely to experience their complaints as more disabling if they are depressed or anxious. Likewise, this can also affect postoperative recovery and satisfaction with the surgical intervention. Management of expectations plays an important role in contentment with surgical outcome and it is therefore relevant to appraise the influence of mental status on outcome of spinal stenosis surgery.

Methods: Patients that underwent decompression for spinal stenosis (450 randomly selected patients operated between 2007-2013) were evaluated with patient reported outcome questionnaires after a mean follow up of 9 years. Questionnaires assessing pain and functionality (Oswestry Disability Score; ODI), quality of life (EQ-5D) and satisfaction with the surgery (Likert-7 point scale) were submitted as well as a questionnaire concerning anxiety and depression (Hospital Anxiety and Depression scale (HADS). ODI, EQ-5D and Likert scale outcome were compared between patients that scored deviant on the HADS score (score ≥ 8) and those that scored non-deviant (HADS score < 8). The outcomes were compared between and within these groups using the independent students t-test and chi-square tests.

Results: 147 patients returned the questionnaires (response rate 33%). 115 patients had a HADS score below 8 (non-deviant cases) and 32 patients demonstrated anxiety and/or depression (deviant cases). In the latter group 69% was female; mean age was not different between the groups. The mean ODI score of the deviant cases was 42.46 ±16.24 in contrast to 18.48 ±18.25 for the non-deviant cases (p < 0.001). The mean EQ-5D score for the deviant cases was 0.55 ­±0.29 whilst the not deviant cases had a mean EQ-5D score of 0.79 ±0.22 (p < 0.001). Perceived recovery (Likert score ≥ 6) was reported in 29.0% of the deviant cases and in 78.3% of the non-deviant cases (p < 0.001).

In the anxious and/or depressed (deviant) group, only 12.5% had both a good functional outcome (ODI ≤ 24) and reported satisfaction with the outcome of surgery (Likert ≥ 6), compared with 58.4% in the non-deviant group. In the deviant group 68.8% had both an inferior functional outcome and a negative perceived recovery score, compared with 14.1% in the non-deviant group. 

Discussion: Patients that report to be anxious and/or depressed demonstrate an inferior long-term outcome after spinal stenosis surgery, in contrast to patients that do not. The difference is convincing and clinically relevant and thus deserves to be addressed in preoperative counseling. Confronting patients with the mean outcome of their peers may improve their expectations of surgery. Future research should be aimed both at the effect of pretreatment with medication to improve anxiety and depression and at the influence of preoperative HADS scores on outcome.