Postoperative Pain Treatment in Patients with Dementia: A Retrospective Observational Study

Inadequate postoperative analgesia has been noted in patients with dementia, but this topic has only been studied in hip fractures. This study aimed to examine whether the duration of postoperative analgesia associated with three surgical procedures was shorter in patients with dementia than in those without dementia.

This retrospective observational study was based on a nationwide discharge database of acute care hospitals in Japan and included patients aged ≥ 65 years diagnosed with lung cancer, rectal cancer, or hip fracture, who underwent surgery in 366 hospitals between April 2013 and September 2018. The primary outcome was the incidence of injectable analgesic use during the postoperative hospital stay. The number of person-days of opioid, non-steroidal anti-inflammatory drug, or acetaminophen use was calculated for patients with and without dementia after each surgery using generalized estimating equations to obtain the age-adjusted incidence per 100 person-days.

Among the 32,379 patients included, 4828 (14.9%) had dementia. The duration of opioid administration per 100 person-days was 14% shorter in patients with dementia than in those without dementia after open rectal cancer surgery (incidence rate ratio [IRR] 0.86; 95% confidence interval [CI] 0.74-1.00) and 20% shorter in patients with dementia after open lung cancer surgery (IRR 0.80; 95% CI 0.70-0.91). In patients who underwent thoracoscopic lung cancer surgery, laparoscopic rectal cancer surgery, or hip replacement surgery, the duration of opioid administration was shorter in patients with dementia than in those without dementia, but the difference was not statistically significant.

The length of postoperative opioid administration after lung and rectal cancer surgery was reduced in patients with dementia, suggesting that the duration of postoperative analgesia in patients with dementia may be insufficient. More careful pain assessment and management of postoperative analgesia in these patients may be necessary.