Opioid Utilization and Perception of Pain Control in Hospitalized Patients: A Cross-Sectional Study of 11 Sites in 8 Countries
BACKGROUND: Hospitalized patients are frequently treated with opioids for pain control, and receipt of opioids at hospital discharge may increase the risk of future chronic opioid use.
OBJECTIVE: To compare inpatient analgesic prescribing patterns and patients’ perception of pain control in the United States and non-US hospitals. DESIGN: Cross-sectional observational study.
SETTING: Four hospitals in the US and seven in seven other countries.
PARTICIPANTS: Medical inpatients reporting pain.
MEASUREMENTS: Opioid analgesics dispensed during the first 24-36 hours of hospitalization and at discharge; assessments and beliefs about pain.
RESULTS: We acquired completed surveys for 981 patients, 503 of 719 patients in the US and 478 of 590 patients in other countries. After adjusting for confounding factors, we found that more US patients were given opioids during their hospitalization compared with patients in other countries, regardless of whether they did or did not report taking opioids prior to admission (92% vs 70% and 71% vs 41%, respectively; P < .05), and similar trends were seen for opioids prescribed at discharge. Patient satisfaction, beliefs, and expectations about pain control differed between patients in the US and other sites.
LIMITATIONS: Limited number of sites and patients/country.
CONCLUSIONS: In the hospitals we sampled, our data suggest that physicians in the US may prescribe opioids more frequently during patients’ hospitalizations and at discharge than their colleagues in other countries, and patients have different beliefs and expectations about pain control. Efforts to curb the opioid epidemic likely need to include addressing inpatient analgesic prescribing practices and patients’ expectations regarding pain control.
© 2019 Society of Hospital Medicine
Study Size
Preliminary data from the internal medicine units at our institution suggested that 40% of patients without cancer received opioid analgesics during their hospitalization. Assuming 90% power to detect an absolute difference in the proportion of inpatient medical patients who are receiving opioid analgesics during their hospital stay of 17%, a two-sided type 1 error rate of 0.05, six hospitals in the US, and nine hospitals from all other countries, we calculated an initial sample size of 150 patients per site. This sample size was considered feasible for enrollment in a busy inpatient clinical setting. Study end points were to either reach the goal number of patients (150 per site) or the predetermined study end date, whichever came first.
Data Analysis
We generated means with standard deviations (SDs) and medians with interquartile ranges (IQRs) for normally and nonnormally distributed continuous variables, respectively, and frequencies for categorical variables. We used linear mixed modeling for the analysis of continuous variables. For binary outcomes, our data were fitted to a generalized linear mixed model with logit as the link function and a binary distribution. For ordinal variables, specifically patient-reported satisfaction with pain control and the opinion statements, the data were fitted to a generalized linear mixed model with a cumulative logit link and a multinomial distribution. Hospital was included as a random effect in all models to account for patients cared for in the same hospital.
Country of origin, dichotomized as US or non-US, was the independent variable of interest for all models. An interaction term for exposure to opioids prior to admission and country was entered into all models to explore whether differences in the effect of country existed for patients who reported taking opioids prior to admission and those who did not.
The models for the frequency with which analgesics were given, doses of opioids given during hospitalization and at discharge, patient-reported pain score, and patient-reported satisfaction with pain control were adjusted for (1) age, (2) gender, (3) Charlson Comorbidity Index, (4) length of stay, (5) history of illicit drug use, (6) history of psychiatric illness, (7) daily dose in morphine milligram equivalents (MME) for opioids prior to admission, (8) average pain score, and (9) hospital. The patient-reported satisfaction with pain control model was also adjusted for whether or not opioids were given to the patient during their hospitalization. P < .05 was considered to indicate significance. All analyses were performed using SAS Enterprise Guide 7.1 (SAS Institute, Inc., Cary, North Carolina). We reported data on medications that were prescribed and dispensed (as opposed to just prescribed and not necessarily given). Opioids prescribed at discharge represented the total possible opioids that could be given based upon the order/prescription (eg, oxycodone 5 mg every 6 hours as needed for pain would be counted as 20 mg/24 hours maximum possible dose followed by conversion to MME).
Missing Data
When there were missing data, a query was sent to sites to verify if the data were retrievable. If retrievable, the data were then entered. Data were missing in 5% and 2% of patients who did or did not report taking an opioid prior to admission, respectively. If a variable was included in a specific statistical test, then subjects with missing data were excluded from that analysis (ie, complete case analysis).
