Treatment patterns of knee osteoarthritis patients in Korea

BACKGROUND/AIMS: To evaluate the treatment patterns of knee osteoarthritis (OA) patients in South Korea. METHODS: Using the Korean nationwide claims database, all knee OA patients in Korea during 2014 were identified by the knee OA diagnostic code (M17) or any OA diagnostic code (M15 to M19) in combination with a procedure for a knee X-ray. Patterns of medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids (CSs), analgesics, and symptomatic slow acting drugs for OA (SYSADOA) were analyzed. Prevalence and characteristics of knee OA patients who received a CS intra-articular injection (IAI) were also evaluated. RESULTS: We identified 2,016,516 knee OA patients whose age (mean ± standard deviation) was 63.2 ± 10.8 years. The number of patients with at least one use of NSAIDs, analgesics, CS, and SYSADOA were 82.5%, 32.2%, 8.6%, and 43.4%, respectively. The use of herbal SYSADOAs was 29.7%. For regular users (medication possession ratios ≥ 50%), the use of NSAIDs was substantially decreased (48.8%), while the use of SYSADOA (37.3%) and CS (6.7%) were not significantly changed. The number of CS IAI users among knee OA patients was 0.18%; they were slightly older (64.4 ± 10.9 vs. 63.2 ± 10.8, p < 0.01) and more skewed towards females (75.7% vs. 71.5%, p < 0.01) than patients who had not received CS IAI. CONCLUSIONS: In Korea, the use of SYSADOA or CS in knee OA patients was relatively high. Further studies on the effectiveness and the safety of these treatment options for knee OA are needed.