A Two-Year Prospective Multicenter Study of Opioid Therapy for Chronic Noncancer Pain: Prescription Trends and Predictors.

Abstract

Opioid use in chronic pain has increased worldwide in recent years. The aims of this study were to describe the trends and patterns of opioid therapy over two years of follow-up in a cohort of chronic noncancer pain (CNCP) patients and to assess predictors of long-term opioid use and clinical outcomes. A prospective cohort study with two years of follow-up was undertaken in four multidisciplinary chronic pain clinics. Demographic data, pain characteristics, and opioid prescriptions were recorded at baseline, three, six, 12, and 24 months. Six hundred seventy-four CNCP patients were recruited. The prevalence of opioid prescriptions at baseline was 59.6% (N = 402), and 13% (N = 86) were strong opioid prescriptions. At 24 months, opioid prescription prevalence was as high as 74.3% (N = 501), and strong opioid prescription was 31% (N = 207). Most opioid users (71%, N = 479) maintained their prescription during the two years of follow-up. Our opioid discontinuation was very low (1%, N = 5). Opioid users reported higher severity and interference pain scores, both at baseline and after two years of follow-up. Opioid use was independently associated with continuous pain, pain location in the lower limbs, and higher pain interference scores. This study describes a pattern of increasing opioid prescription in chronic pain patients. Despite the limited improvement of clinical outcomes, most patients keep their long-term opioid prescriptions. Our results underscore the need for changes in clinical practice and further research into the effectiveness and safety of chronic opioid therapy for CNPC.