To study prognostic value of different biochemical markers for morphological progression of early knee osteoarthritis.
A total of 89 patients with knee osteoarthritis (OA) were enroled into the study. The follow-up period was 2 years. Radiological OA progression was evaluated by measuring joint space width. Pentosidine was detected using the HPLC method described earlier, cartilage oligomeric matrix protein (COMP) using the method published by our team. MMP-9, tissue inhibitors of metalloproteinases (TIMP), YKL-40 and hyaluronic acid were detected using commercially available kits.
In the group of patients suffering from knee OA, higher serum levels of pentosidine (P=0.04), MMP-9 (P=0.02), TIMP (P=0.04) and COMP (P=0.05) were detected compared with healthy control subjects. Using a correlation analysis method, it has been found that the patients with higher basic serum levels of hyaluronic acid had a faster radiological progression (r=0.56, P<0.005), as well as the patients with higher basic serum pentosidine levels (r=0.30, P<0.005). Other biochemical markers had no statistically significant prognostic value.
In our study, serum levels of hyaluronic acid and pentosidine had a predictive value for further development of knee OA in that further joint space narrowing was detected in the patients with knee OA in the next 2 years.