Abstract:

Objective To analyze the factors influencing the analgesic effect of pain in advanced cancer patients with moderate or severe chronic pain， and

provide some references to palliative care for advanced cancer patients. Methods Data were collected from 260 advanced cancer patients with moderate or severe chronic pain. All the patients received standard analgesic treatment. Pain intensity numerical rating scale（NRS）≤3， breakthrough pain≤3 times/day， salvage treatment number ≤3 times/day were used as the indicators of good pain control. Pain control after 3 days’ treatment， the analgesic time and analgesic doses needed for stable pain control were chosen as the evaluation indicators of analgesic complexity. The influences of following factors on the analgesic effects were analyzed， including gender， age， type of tumor， having bone metastases or not， pain intensity， pain location， pain causes， pain mechanism and having frequent breakthrough pain（more than 3 times a day） or not. Results In this study， 75.4% of the 260 patients had good pain control（NRS≤3） in 3 days， and the median analgesic time was two days. Logistic regression and Cox regression analyses showed that digestive system carcinoma， severe pain and frequent breakthrough pain were independent risk factors of poorer pain control in 3 days（P value were 0.032，＜0.001，＜0.001， respectively）， and also needed longer time for stable pain control（P value were 0.042， 0.002， 0.013， respectively）， while gender， age， bone metastases， pain location， pain causes and pain mechanism had no relationship with 3 days’ pain control and the time of analgesia（P＞0.05）. Of 185 patients who used strong opioids， patients younger than 60 years old（P=0.018）， or those with severe pain（P＜0.001）， neuropathic pain（P=0.002）， frequent breakthrough pain（P=0.015） needed more analgesic drugs， while gender， type of tumor， bone metastases， pain causes and pain location had nothing to do with the analgesic doses（P＞0.05）. Conclusion Younger than 60 years old， digestive system carcinoma， severe pain， neuropathic pain and frequent breakthrough pain were risk factors of pain control.