Background and Purpose: Chronic postoperative pain (CPSP) after cardiac surgery can cause severe health problems. As demonstrated in noncardiac surgeries, preoperative chronic pain can potentially lead to CPSP. However, the association between preoperative chronic pain and CPSP over follow-up in cardiac surgical settings in the context of sex differences is still lacking. This observational study aims to explore the role and sex differences of preoperative chronic pain in the occurrence and development of long-term CPSP and CPSP-related complications after cardiac surgery.
Patients and Methods: This observational study enrolled 495 patients (35.3% women) who underwent cardiac surgery via median sternotomy in March 2019. Validated questionnaires were delivered to assess preoperative chronic pain and moderate to severe CPSP at 3 and 24 months following surgical procedures. The secondary outcomes included the occurrence of moderate to severe chronic pruritus, sleep disturbance, and daily activities interference at follow-up. Multivariable logistic regression was employed.
Results: Of 495 patients analyzed, the incidences of preoperative chronic pain (29.7% versus 20.6%) and moderate to severe CPSP (14.8% versus 8.1%) were both higher in females than males. Female sex (P = 0.048) and preoperative chronic pain (P = 0.008) were identified as significant risk factors for CPSP occurrence. However, preoperative chronic pain contributed significantly to CPSP (P = 0.008), sleep disturbance (P =0.047), and daily activities interference (P =0.019) in females, but not in males.
Conclusion: The 2-year prevalence of moderate to severe CPSP after cardiac surgery was 10.5%. Compared to males, females are more susceptible to CPSP and pain-related outcomes in the long term. In addition, preoperative chronic pain was associated with a higher risk of CPSP in females but not in males.
Keywords: cardiac surgery, chronic postoperative pain, preoperative chronic pain, sex differences