The Impacts Of Pre-surgery Emotional Distress On Post-operative Pain Outcomes: Meta-analysis And Longitudinal Study

Pain is the most common concern after surgery. Post-operative pain has both high incidence and serious harm. High levels of acute post-surgical pain (APP) contribute to poor recovery, delayed discharge, reduced satisfaction and increased costs. In addition, intense APP can develop in chronic post-surgical pain (CPSP) which affects patients life quality, results in physical disability and causes emotional distress. Pre-surgery emotional distress has been linked to APP and CPSP, yet conclusions of past studies on its impact have varied. In addition, because nearly all past studies of risk factors for post-operative pain have been conducted in foreign countries, there is a need to assess the impact of pre-operative emotional distress and other pre-operative experiences on post-operative pain in Chinese surgery patients.In Study 1, a meta-analysis was conducted on longitudinal studies to evaluate overall strengths of relation between pre-surgical emotional distress and key post-surgical pain outcomes (i.e., pain intensity, analgesic use, functional impairment) and to identify moderators that help to explain effect size variability between studies. Thirty-nine prospective studies (N=4449) met selection criteria for meta-analysis. High levels of pre-surgery general emotional distress were associated with significantly more post-surgical pain, impairment and analgesic use following surgery. Moderator analyses for relations between pre-surgery distress and post-operative pain intensity indicates effect sizes were larger in studies that assessed catastrophizing, anxiety, and depression relative to other types of emotional distress, those with intervals of two months or less between surgery. Type of surgery was the only significant moderator of pre-surgical distress-impairment relations; effect sizes were smaller in studies of spine surgery than other types of surgery. Besides, meta-regression showed that age was a significant moderator for distress-analgesic relation, indicated that effect sizes were stronger in older than younger samples; Underscoring the salience of significant moderators in accounting for inconsistent findings between studies, heterogeneity was either reduced or no longer significant after statistically controlling for their impact. Finally, within studies that statistically controlled for effects of baseline responses on outcomes, associations between pre-surgery emotional distress and follow-up pain intensity and impairment levels were attenuated but remained significant, suggesting heightened pre-surgery emotional distress increase is a risk factor for, not merely a correlate of poorer post-operative outcomes.Study 2 was designed to assess the impact of pre-surgery measures of demographic factors, pain experiences, emotional distress, and beliefs about pain on acute post-operative pain intensity and analgesic use. Ninety-four consecutive patients undergoing surgery procedures (40 men,54 women) were included in the final sample. Baseline assessments (T1) were conducted one day before surgery. Participants completed a brief battery of measures that assessed pre-surgery pain experiences (i.e., surgery-related pain, surgery-unrelated pain, pain intensity and pain interference), demographic information (i.e., age, height, weight, education level and marital status), emotional distress (i.e., fear of movement/surgery, depression), and pain beliefs (i.e., catastrophizing, pain self-efficacy). Follow-up assessments (T2) of pain intensity and analgesic use were conducted 2-3 days after surgery. Bivariate analyses showed that APP and analgesic use were both related to preoperative pain intensity, In addition, depression scores, and the helplessness dimension of pain catastrophizing had significant positive correlations with increased intensity of APP. However, after controlling for the impact of pre-operative pain intensity levels and surgery duration, hierarchical regression analysis showed that depression and helplessness dimension of pain catastrophizing were no longer significant.Both the meta-analysis on longitudinal studies and the longitudinal study of Chinese surgery patients indicated preoperative emotional distress, particularly depression and facets of pain catastrophizing are related to postoperative pain outcomes. Together, findings indicate preoperative emotional distress should be assessed in both research and clinical practice focused on understanding postoperative outcomes and pain management.