Depression is a common co-morbid condition seen in arthroplasty patients. Pain and depression have been understood to influence one another, which may explain why this patient group experiences higher rates of depression than the general population. Arthroplasty can relieve pain and improve function, which may thereby initiate an improvement in the patient's depressive symptoms.
This retrospective study examined physical and mental domain outcomes of Short Form-36 health-related quality of life questionnaire among 146 patients who underwent primary hip or knee arthroplasty for osteoarthritis at a single institution during 2001-2004. These patients were classified into "depressed/anxious" and "non-depressed" groups based on their pre-operative mental component summary (MCS), with MCS < 42 defining depression. MCS and the subscales from the 36-Item Short-Form Health Survey form expected to be influenced by arthroplasty, Physical Function, Pain, and Role Physical were examined at 3 months and 1 year post-operative.
At 1 year, 66.7% of the "depressed/anxious" group reported MCS > 42, suggesting improvement of their depressive symptoms. Both groups reported similar improvements in their 36-Item Short-Form Health Survey subscale scores for Pain and Physical Function. However, the depressed group's scores were lower than the non-depressed group's at all time points.
Arthroplasty significantly improved Physical Function and Pain in depressed patients, while their depressive symptoms improved. This improvement may be in response to the resolution of physical symptoms and represents an additional benefit to this elective surgery. Further studies, in larger populations, are needed to establish patient characteristics associated with non-resolution of depressive symptoms and the role of mental health interventions to optimize outcomes for hip and knee arthroplasty patients.