If you are a physician who provides spine consultations for your emergency department, it may seem as though every patient who complains of low back pain (LBP) has undergone an MRI that shows some minor pathology that triggers a spine consult. As spine consultants, we have a very biased view in that we never hear about the scores of LBP patients who receive no imaging and are discharged with a prescription for pain medication. This week we discuss Dr. Friedman’s article describing the rates of diagnostic testing and treatment provided to patients who present to emergency rooms with back complaints. This study utilized the National Hospital Ambulatory Medical Care Survey (NHAMCS), a database that samples emergency room utilization and extrapolates their results to create an estimate of nationwide trends. In order to generate their cohort, the authors included patients with ICD-9 codes and reason for visit codes indicative of low back complaints after excluding motor vehicle accident patients and those under age 14. They reported that the rate of cross-sectional imaging (CT scan or MRI) increased three-fold from 2002 to 2006 (3.2 to 9.6%) and that 61% of patients were discharged with narcotic medication. Over two percent of all emergency room visits were for LBP.
From a resource utilization perspective, it is concerning that the rate of cross-sectional imaging tripled in 4 years. It seems highly unlikely that three times as many patients presented with “red-flag” symptoms that would trigger the use of advanced imaging. Even more concerning was that Medicaid patients were 50% less likely to get advanced imaging compared to patients with private insurance, and self-pay patients were 75% less likely. While the tripling of advanced imaging use is likely due to an increased availability of MRI scanners in emergency rooms (an example of supply-sensitive care1) and possibly due to increasingly “defensive” medicine, the extremely strong relationship between insurance status and rate of advanced imaging suggests more sinister motives underlying the imaging decision-making process. The authors found no relationship between geographic region and advanced imaging use, though this is likely due to the fact they used only four large areas in their analysis. A comparison based on hospital referral regions would almost certainly show strong regional patterns of utilization.2 The other concerning finding in this study is that 61% of patients were discharged on opioids. While this may be “appropriate given the high rate of moderate and severe pain at triage” according to some treatment recommendations, it seems that such widespread emergency prescription of narcotic medication for LBP is potentially dangerous and should be investigated more thoroughly. Such a practice might make life easier for the emergency room clinician, but it could have potentially devastating results for patients and society.
How can we use these findings? Given that these are basically descriptive results obtained from a database, conclusions about the underlying causes of the findings and appropriate utilization rates are not possible. This is certainly a hypothesis-generating study that should prompt investigators to determine if recommendations for advanced imaging and narcotic prescription are actually being followed (this seems unlikely), and, if not, why not? In addition, the inappropriate use of insurance status in the diagnostic imaging algorithm needs to be scrutinized and the practice of the emergency room wallet-biopsy eliminated. This article is yet another example of overutilization of expensive medical technology, and evidence-based practice guidelines should be better disseminated in order to prevent such waste. Please read Dr. Friedman’s article and accompanying commentary, and let us know your thoughts about emergency room diagnosis and treatment of LBP by posting a comment on the blog.
Adam Pearson, MD, MS
1. Fisher ES, Wennberg JE. Health care quality, geographic variations, and the challenge of supply-sensitive care. Perspect Biol Med 2003;46:69-79.
2. Weinstein JN, Lurie JD, Olson PR, Bronner KK, Fisher ES. United States' trends and regional variations in lumbar spine surgery: 1992-2003. Spine (Phila Pa 1976) 2006;31:2707-14.