A pharmacovigilance data recording system of adverse events in patients with long-term opioid use for the management of chronic noncancer pain may be effective for improved control of pharmacologic pain therapy, according to a study published in Acta Anaesthesiologica Scandinavica.
This retrospective review examined questionnaire responses from 753 patients taking opioid analgesics for chronic noncancer pain. These questionnaires sought to evaluate pain intensity (evaluated with a visual analog scale [VAS]), adverse events (AEs), and use of healthcare resources. In addition, physicians were asked to fill out questionnaires regarding morphine equivalent daily dose (MEDD) prescribed and suspected adverse drug reaction (ADRs) using the Spanish Pharmacovigilance System. Patients with suspected ADRs were categorized as “case” patients (n=150; at follow-up, n=126), and the remaining participants were categorized as control patients (n=603).
The most frequently prescribed opioid medications in this cohort were fentanyl and tramadol, and 89% of patients were taking concomitant drugs. Case vs control patients reported greater pain intensity (VAS score, 67±26 vs 59±30 mm, respectively; P <.05) and a higher number of AEs (8±6 vs 5±3 AEs per patient, respectively; P <.01). Case patients who had >1 follow-up reported reduced numbers of AEs (6±3 AEs per patient; P =.005). In addition, case vs control patients reported greater use of polypharmacy related to pain (65% vs 34%, respectively; P <.01) and higher MEDD (mean, 139±130 vs 106±99 mg/day; P <.01). Higher pain-related changes in pharmacologic pain therapy were observed in case vs control patients.
A limitation of the analysis was the reliance on patient-reported data and subjective measures of therapy efficacy.
“It is important to ask patients about AEs that they might have, also to register in the clinical history and note the ADR that the physician considers associated with the patient’s treatment,” the researchers noted. “Then, a follow-up of both, AE and ADRs, should be done by the physician to analyze if a modification in the therapeutic treatment is needed (deprescribing or prescribing a new treatment) and if the AE/ADR is resolved.”
Planelles B, Margarit C, Ajo R, et al. Health benefits of an adverse events reporting system for chronic pain patients using long-term opioids [published online August 14, 2018]. Acta Anaesthesiol Scand. doi: 10.1111/aas.13243