DO PAIN CATASTROPHIZING, DEPRESSION, AND MENTAL HEALTH INFLUENCE POSTOPERATIVE OUTCOMES FOLLOWING TOTAL HIP ARTHROPLASTY?

Total hip replacement (THR) is the definitive treatment for degenerative conditions of the hip with an excellent track record for success. However, there is emerging evidence that patients with musculoskeletal conditions suffering from concomitant psychological and/or mental health ailments may be predisposed to suboptimal outcomes after surgery. Determining whether psychological and mental health influence outcomes following Total Hip Replacement (THR)—and to what extent—has important prognostic, preventive, and therapeutic implications. In this study, we evaluated the influence of pre-operative pain catastrophizing, depression, and/or mental health on post-operative clinical outcomes following THR. We evaluated outcomes as part of a secondary analysis in a prospective cohort observational study of patients undergoing THR. We employed a multivariable mixed model regression analysis to determine whether pain catastrophizing, depression, or mental health was associated with persistent pain, decreased function, and/or higher risk of revision surgery pre-operatively and up to 5 years post-operatively. A Pain Catastrophizing Scale (PCS) score of 30 or above was pre-defined as the threshold for clinically important pain catastrophizing. Depression and mental health were reported and analyzed as binary categorical variables. We used the ICOAP to measure constant and intermittent hip pain and the WOMAC Physical Function measure to measure physical function. A p value of less than 0.05 was considered as statistically significant. The study cohort consisted of 576 patients who underwent THR (49.3% male; 50.7% female), divided into 189 who screened positive for a psychological, mental health, or pain catastrophizing and 387 who did not. All patients improved substantially following THR, with large significant and clinically important improvements between pre-operative and all post-operative follow up time points for both groups. After adjustment, constant pain scores (ICOAP Constant) were 1.35 (SE 0.18) higher in those with a PCS score >= 30 (p = 30. Female sex was also significantly associated with higher pain scores. Physical function scores (WOMAC PF) were 4.61 (SE 0.53) higher (i.e. worse) in those with PCS > = 30. Younger age at surgery and female sex were also associated with higher WOMAC PF scores (i.e. worse function). History of depression or mental health disorder were not significant in the model. Patients with high levels of pain catastrophizing show large improvements in pain and function following THR. However, these patients have higher levels of pre-operative and post-operative pain and lower physical function following THR. Although the differences are small, pain catastrophizing may be used as one element of a risk stratification model to estimate risk of poor post-operative outcome following THR. Whether targeted interventions to address pain catastrophizing can improve surgical outcome remains to be investigated.