Opioid tolerance--a predictor of increased length of stay and higher readmission rates.

The increasing use of opioids to manage pain in the United States over the last decade has resulted in a subset of our population developing opioid tolerance. While the management of opioid tolerant patients during acute episodes of care is well known to be a challenge amongst health care providers, there is little in the literature that has studied opioid tolerance as a predictor of outcomes. We conducted a review on all admissions to Massachusetts General Hospital over a period of 6 months, from January 2013 to June 2013, and identified opioid tolerant patients at admission using the FDA definition of opioid tolerance. To compare risk adjusted groups, we placed opioid tolerant patients and control patients into groups determined by expected length of stay of less than 2 days, 2 to 5 days, 5 to 10 days, and greater than 10 days. Opioid tolerant patients were then compared to the control for outcomes measures including observed length of stay and readmission rates. Our results show that all opioid tolerant patients have a significantly longer length of stay and a greater 30 day all cause readmission rate than the control group (P < 0.01). This trend was found in the first 3 risk adjusted groups, but not in the fourth group where expected length of stay was greater than 10 days. The opioid tolerant population is at risk given the poorer outcomes and higher health care costs associated with their care. It is imperative that we identify opportunities for improvement and delineate specific pathways for the care of these patients.