Personalized Pain Goal as an Outcome Measure in Routine Cancer Pain Assessment

Abstract

Background: There is currently no universally accepted outcome measure in cancer pain management. The personalized pain goal (PPG) has been shown to be a relevant outcome measure. We examined its use in routine outpatient practice and compared it with the clinically important difference (CID, ≥2 points or 30%), a pain outcome measure frequently used in several clinical studies.

Measures: Initial and follow-up clinical information of outpatients with advanced cancer pain were retrospectively reviewed. PPG response was defined as pain ≤ PPG and CID response as ≥30% or ≥2-point decrease in pain intensity at follow-up.

Outcomes: PPG was successfully completed in 375 of 387 eligible patients (97%) with cancer pain. The median baseline PPG was three for all patients and remained unchanged at follow-up. One hundred thirty-two of 375 (35%) had a PPG response and 243 of 375 (65%) were non-responders. The odds ratio for PPG non-response was 1.01 for each milligram increase in morphine equivalent daily dose (P = 0.001), 1.46 for each point increase in the number of adjuvant analgesics (P = 0.006), 2.63 for severe pain (P = 0.002), and 2.55 for moderate depression (P = 0.006). Using PPG response as the gold standard for pain relief, the overall sensitivity and specificity of CID response were 83% and 77%, respectively.

Conclusion: PPG was successfully completed in the vast majority of patients, suggesting its feasibility as a pain outcome measure in routine clinical practice. Higher baseline pain intensity, depression, opioid dose, and number of adjuvant analgesics were independent predictors of poor pain relief. Further research is needed to further evaluate its clinical importance in cancer pain management.

Keywords: Cancer pain; clinical; goal; outcome measure; personalized; response.