To compare the medical costs associated with treatments for knee osteoarthritis (OA): intra-articular corticosteroids (ICS) and intra-articular hyaluronic acid (IHA) primarily, and ICS/IHA vs knee arthroplasty (TKA) secondarily.
This was a retrospective analysis of an insurance claims database. Eligible members had diagnosed OA and no claims for ICS, IHA, or TKA during the 6-18-month look-back period. Cohorts of interest over the 4-year observation period were: patients who received ICS only, those who received IHA only, and those who received TKA only. Outcomes assessed included: (1) total allowed medical costs, (2) claims for pre-specified, treatment-related adverse outcomes and costs, and (3) opioid and/or prescription analgesic use and costs. Data extraction began on the date of the first ICS, IHA, or TKA in 2013 until December 31, 2017.
Of the 260,828 patients who qualified, 126,831 were taking monotherapy (IHA=3703, ICS=117,588, TKA = 5540). Adjusted 4-year per patient per month (PPPM) costs were lowest in the IHA cohort ($733); PPPM costs were $1230 in the ICS cohort and $1548 in the TKA cohort. A smaller percentage of patients in the IHA (7.1%) vs ICS (8.4%) or TKA cohort (11.8%) experienced any of the pre-specified adverse outcomes. Adverse outcome-related costs in the IHA cohort were lower ($19.91) than costs in the ICS ($32.18) and TKA cohorts ($31.12). Per-patient opioid and analgesic prescriptions were consistently and significantly lower in the IHA (range, 0.70-0.96) vs ICS cohort (range, 2.0-2.26) for Years 1 through 4. Usage rates were significantly lower in the IHA cohort vs TKA cohort in Year 1 (0.96 vs 4.77) and not different in Years 2 through 4 (TKA range, 0.76-1.08). In Year 1, opioid and prescription analgesic costs were significantly lower in the IHA vs ICS and TKA cohorts ($3.45 vs $11.14 and $12.82). After Year 1, opioid and prescription analgesic costs were significantly higher in the ICS (range, $13.83-15.96) vs IHA (range, $3.02-3.87) and TKA cohorts (range, $3.43-4.97).
Patients in the IHA cohort had lower total medical care costs, fewer adverse outcomes, and lower use/costs of opioids and prescription analgesics vs patients in the ICS and TKA cohorts. Reducing total medical care costs and minimizing opioid/analgesic use should be a treatment goal when selecting therapies for patients with knee OA.