Patients initially prescribed opioids for chronic noncancer pain were found to continue the treatment over long periods of time, despite poor clinical improvement, according to the results of a 2-year prospective study published in Pain Medicine.
In this cohort study, patients with chronic noncancer pain were followed for 24 months at 4 multidisciplinary chronic pain clinics. Study participants had pain that lasted ≥3 months and patients were recruited at the first clinical consultation. The investigators collected demographic data, pain characteristics, and opioid prescription information at baseline and at 3, 6, 12, and 24 months. The International Association for the Study of Pain Taskforce on Pain Classification for the International Classification of Diseases-11 was used to classify pain.
A total of 674 patients with chronic noncancer pain were included in the final analysis. At baseline, the prevalence of opioid prescriptions was 59.6% (n=402), with 13% of patients (n=86) taking strong opioid prescriptions. The prevalence of opioid prescriptions was 74.3% at the 24-month follow-up, with a prevalence of strong opioid prescription of 31%.
The majority of patients using opioids at baseline continued to maintain their prescription during the 24 months (71%) of the study and reported high pain interference and severity scores at baseline and at the 24-month follow-up. The use of opioids was found to be associated with continuous pain as well as pain location in the lower limbs. Only 1% of study participants discontinued their opioid prescriptions during the follow-up period.
Study limitations include the lack of a randomized control design and the lack of assessment of aberrant opioid use in the cohort.
“Further evidence must rely on epidemiological real-world longitudinal studies to assess the effectiveness and safety of long-term opioid use, dose-related risk, and benefit profiles in patients [with chronic noncancer pain],” the researchers noted.
Veiga DR, Mendonça L, Sampaio R, Castro-Lopes JM, Azevedo LF. A two-year prospective multicenter study of opioid therapy for chronic noncancer pain: prescription trends and predictors [published online December 26, 2018]. Pain Med. doi: 10.1093/pm/pny275