Background and aims:
With our ageing population, the number of elderly people undergoing surgical procedures is increasing. The incidence and intensity of postoperative pain in elderly patients is poorly described. This study aims to examine the influence of ageing on postoperative pain, administering opioids and wish for treatment.
Methods: 
After ethical approval and receiving informed consent, international data of surgical patients undergoing spine surgery, total hip replacement, total knee replacement or laparoscopic cholecystectomy were collected between 2010 and 2018 as part of the PAIN OUT program, an international European Union-funded registry. Pain was measured on postoperative day 1 (POD1) using the Numeric Rating Scale (NRS) from 0 – 10. We performed a linear regression or binary logistic analysis for continuous or dichotomous outcomes, respectively.
Results: 
A total of 11.971 patients underwent one of the afore mentioned types of surgery. The reported maximum pain levels decreased significantly with age (β = -0.008, p<0.001). The age related decrease in pain scores was more pronounced in women compared to men (Figure1). The number of times of administering opioids on the ward decreased significantly with ageing (β = -0.012, p<0.001) and the wish for more treatment decreased also with ageing (β = -0.008, p<0.001).
Conclusions: 
Maximum pain scores on POD1 decrease with increasing age in both men and women. Older patients were administered less often opioids and had less often a wish for more pain treatment than younger patients.

INFLUENCE OF AGING ON POSTOPERATIVE PAIN: RESULTS FROM THE INTERNATIONAL PAIN OUT REGISTRY