OBJECTIVES: Osteoarthritis (OA) of the hip/knee is among the most common chronic pain conditions worldwide accounting for a large part of the global burden of pain diseases. The treatment of OA patients ranges from conservative therapy regimen (e.g., pharmacological pain management) to more invasive treatments (e.g., joint replacement). Currently, there is a lack of real world evidence regarding the interval between conservative and invasive treatment approaches in German healthcare. Based on potency-related therapeutic drug classes, this study addresses this information gap by investigating the long-term pain management pathways of OA patients before joint replacement.

METHODS: The study was conducted in a retrospective cohort design using aggregated pseudonymized German health claims data from the InGef database. The analyses focused on OA patients with at least one opioid prescription within a five-year observation period before joint replacement. To derive pathways, individual drug class assignment was determined biannually based on the prescribed medication of highest therapeutic potency.

RESULTS: N=4,494 patients were included in the study population. Overall, the therapeutic potency and the migration behavior between drug classes increased with proximity to the joint replacement. Thereby, major switches occurred mainly in the ultimate year before joint replacement. In particular, there were patients who remained in drug classes of lower therapeutic potency (e.g., non-opioid analgesics) for most of the time and migrated to a drug class of high therapeutic potency (e.g., morphine) only in the immediate year before joint replacement. The duration of treatment with pain medication of higher potency was comparatively short for these patients.

CONCLUSIONS: It is widely agreed that a joint replacement should be postponed for as long as possible in a patient career. The results of this study indicate an unmet medical need for an adequate pain medication of higher potency to cover the interval between conservative and more invasive treatment.