Pre-admission escalation rate of daily opioid consumption (PERDOC), and total morphine equivalent daily dose on the first complete day of admission (D1-MEDD) to a tertiary-level palliative care unit (TPCU): Correlates and predictors in patients with advan

Abstract

9065 Background: Although animal laboratory studies attest to opioid tolerance (OT), it can be difficult in clinical practice to determine whether substantive escalation in opioid dose (average of >5% per day between initial daily dose and maximum daily dose to date) is due to disease progression (DP) or decreased opioid responsiveness, which in turn may be due to OT or other factors. Our study aims were to determine (1) the frequency of PERDOC>5%, (2) the correlates and predictors of PERDOC>5% and D1-MEDD. Methods: We retrospectively examined TPCU patient database records for demographics, physician rating of PERDOC in the Edmonton Staging System (ESS) for cancer pain classification, Edmonton Symptom Assessment System (ESAS) scores, and D1-MEDD. Consecutive 1st admission data on patients surviving >3 days were included in the initial analysis. Using complete data, logistic regression and multiple regression models were created with PERDOC>5% and logn D1-MEDD, respectively, as dependent variables. Results: From 1,351 patients who met the initial descriptive analysis eligibility criteria, 1212 (90%) had an ESS rating for PERDOC. The prevalence of PERDOC>5% was 274/1212 (19.3%). Bivariate analysis (N=969, complete data) showed that PERDOC>5% was positively associated (p<0.05) with younger age, neuropathic pain component (NPC), a pathological level of psychological distress (PLPD), substance abuse, higher D1-MEDD, and higher ESAS pain score (ESAS-P). In the multivariate analysis, NPC (Odds ratio: 2.1, 95% confidence interval: 1.5–2.9), PLPD (1.7, 1.2–2.6), and higher D1-MEDD (2.2, 1.03–4.7) were the strongest independent positive predictors, and ESAS-P (1.01, 1.003–1.02) remained as a weaker predictor. In the D1-MEDD regression model, positive predictors (p<0.05) were younger age, NPC, incident pain, PERDOC>5%, PLPD, ESAS-P and ESAS anxiety scores. Conclusions: Aside from OT and DP, the multiple predictors identified for PERDOC>5% and D1-MEDD underscore the need for a systematic multidimensional assessment of cancer pain that incorporates psychological and physical characteristics. No significant financial relationships to disclose.