Background: The aim of the present study was to assess factors influencing opioid persistence in a large patient cohort of 32,158 patients receiving opioid treatment for either chronic non-malignant or cancer pain.
Methods: Data from 32,158 patients with first-time prescription of an opioid in the timeframe from January 2009 until December 2013 treated in 115 orthopedic, 104 neurological and 1129 general practitioner practices were retrospectively analyzed (Disease Analyzer database Germany). A Cox proportional hazards regression model was used to estimate the relationship between non-persistence and the demographic and clinical variables described previously for a maximum follow-up period of 1 year.
Results: After 1 year of follow-up, 69% of patients treated with opioids had stopped medication intake (refill gap of 90 days). There was a significantly increased risk of treatment discontinuation for younger patients (<40 years HR: 1.45; 41-50 years HR: 1.37; 51-60 years HR: 1.23; 61-70 years HR: 1.22) as compared with patients aged >70. Cancer pain was associated with a significantly lower risk of therapy discontinuation (HR: 0.69), whereas persistence was considerably less probable for diagnoses such as various kinds of back pain (HR: 1.26), osteoarthritis (HR: 1.14) and spondylarthritis (HR: 1.09). Chronic comorbidities such as diabetes, hypertension, heart insufficiency, and dementia were associated with a decreased risk of treatment discontinuation.
Conclusion: Our study showed that persistence with opioid treatment is associated with cancer pain, chronic comorbidities and depression, while younger age and chronic non-malignant pain (especially due to back pain) increase the possibility of opioid discontinuation. It will be the task of future studies to assess reasons for opioid discontinuation in more detail, which is an important step towards improving patient care and health outcomes.
Keywords: Cancer; Opioid; Pain; Persistence.