Study design: Prospective design in which 102 patients were evaluated with a battery of psychological assessment tests 1-2 weeks before surgery, and outcome was assessed 6 months and 1 year after surgery.
Objectives: The study examined whether three aspects of psychological distress (depression, anxiety, and hostility) predict several surgical outcomes (employment status, subjective pain change ratings, and changes in functional abilities).
Summary of background data: Surgery for back pain has been shown to yield poor results in 15-45% of patients. Tools are needed to identify those "at risk" for poor outcome. Aspects of emotional distress, including anxiety, depression, and hostility, have been found to be relevant to various illness outcomes (e.g., cancer, heart disease), but their influence has not been prospectively evaluated for back pain surgical outcome.
Methods: Study patients completed measures of distress before surgery, including the Spielberger Trait Anxiety Inventory, Zung Depression Scale, Modified Somatic Perception Questionnaire, and Cook-Medley Hostility Scale. At 1-year follow-up, patients completed pain change ratings, functional abilities measure (Dallas Pain Questionnaire), and questions about employment status.
Results: Multivariate regression analyses, controlling for significant demographic variables, found that failure to return to work was predicted by presurgical anxiety (P < 0.001) and depression (P < 0. 01); failure to report improvement in pain was predicted by presurgical somatic anxiety (P < 0.01) and depression (P < 0.058); and failure to report improved functional abilities was predicted by presurgical somatic anxiety (P < 0.01) and depression (P < 0.05). Hostility did not predict any outcome. Regression analyses found a strong predictor to be a combination of the Zung Depression Scale and Modified Somatic Perception Questionnaire, known as the Distress and Risk Assessment Method (DRAM).
Conclusions: These results indicate that screening for presurgical distress is likely to identify those patients at risk for poor outcome. Studies to evaluate whether presurgical psychological treatment improves outcome are warranted.