An academic interventional pain clinics’ independent review of pharmacologic adherence: What do we know?
Lauren McLaughlin DO, Amanda Wallace MD, Rachael Rzasa-Lynn MD
Health care providers treating patients with chronic pain often experience that medication is not as effective as expected, questioning medication effectiveness or patient adherence. Medication adherence has been extensively studied in numerous chronic conditions such as asthma, hypertension, cancer, and post-transplantation, and is gaining attention, especially in such chronic conditions, because it affects treatment outcomes. We performed a retrospective chart review comparing the patient-reported medication list on the day of initial consultation to the urine toxicology results collected the same day. Two different forms of medication non-adherence are considered: underuse and overuse. The purpose of this study is to describe the adherence/nonadherence rate of our academic pain clinic patient population.
This study investigates the incidence of medication adherence in an academic chronic pain clinic by applying objective methods. IRB approval was given for a retrospective chart review of urine toxicology results on new patients seen in the interventional chronic pain clinic from September 1, 2014 –March 31, 2015. Urine samples were screened for pain-related prescription and illicit compounds using LC/MS/MS which is a triple mass spectrometry system with a mass accuracy of 0.01%. This technology identifies and confirms more than 500 prescriptions, illicit and over-the-counter drugs, in one test. One-hundred-eighty-four consecutive new patients were seen and 93 urine toxicology screens were acquired and reviewed. The pain-related medications detected on urine toxicology were compared to those listed on the patient’s current medication list the day the sample was provided. Quantitative urine concentrations were evaluated in a qualitative way: any positive finding was considered to be ‘detected’.
A total of 184 new patients were seen. A total of 90 patients refused or were not able to give a urine sample, resulting in 93 (50%) urine toxicology samples. Two types of noncompliance were defined: under-reporting (detection of non-reported substance) and over-reporting (reported substances undetectable). In total, 823 drugs were detected (including both prescribed (80%) and non prescribed (6.2%) medications) and 254 drugs were undetected (over-reported). Of the 254 over-reported drugs, the majority were antidepressants (43%) and anticonvulsants (40%), with opiates at 13%. The underreported medications were primarily antidepressants (22%) and opiates (20%).
Our findings of 28.4% noncompliance in pain patients are in agreement with the reported incidence of other chronic conditions in the literature presenting a median of 29% (9-45%). A discrepant result from previous studies is the low incidence of under-reported opioids with 20% in our pain clinic vs 37% nationally. Our results highlight an area of improvement in patient education. The majority of over-reported/under-reported medications were antidepressants and anticonvulsants which have become increasingly popular adjuncts to multimodal pain treatment regimens. The research supporting the use of these medications has been encouraging, however patients may not fully understand how these medications are to be taken and they may underestimate the usefulness of these substances. Over-reporting may also reflect patient non-compliance due to fear of addiction, avoidance of unpleasant side effects, or perceived inefficacy of the medication. Further research is required in terms of drug assessment and adherence improvement strategies in pain clinics, including modifiable psychosocial and behavioral characteristics of patients. Screening for medication compliance in chronic pain patients is helpful to avoid discomfort to the patient, further workup, and deterioration of the doctor-patient relationship.