Urinary CTX-II and glucosyl-galactosyl-pyridinoline are associated with the presence and severity of radiographic knee osteoarthritis in men.
Jordan KM., Syddall HE., Garnero P., Gineyts E., Dennison EM., Sayer AA., Delmas PD., Cooper C., Arden NK.
OBJECTIVE: To investigate the association between biochemical markers of bone, cartilage, and synovial turnover with the presence and severity of knee osteoarthritis (OA) in men. METHODS: 176 men aged 59-70 years from the MRC Hertfordshire Cohort were studied. Weightbearing anteroposterior and lateral semiflexed radiographs were taken of both knees. A lifestyle questionnaire including basic demographic details and a questionnaire detailing knee pain was completed. This random sample was stratified based on the Kellgren and Lawrence (K&L) score, and the following biochemical markers were analysed: serum osteocalcin, serum C-terminal crosslinked telopeptide of type I collagen (CTX-I), urinary C-terminal crosslinked telopeptide of type II collagen (CTX-II), and urinary glucosyl-galactosyl-pyridinoline (Glc-Gal-Pyd). RESULTS: Age, body mass index (BMI), social class, smoking, and alcohol consumption were similar across K&L grades. Only one subject had a grade 4 K&L score, and was amalgamated with grade 3 subjects. A strong significant association was found between the presence of knee OA and urinary CTX-II and urinary Glc-Gal-Pyd (p=0.0001 and p=0.009), which persisted after adjustment for age and BMI. A significant positive association was also found between urinary CTX-II and urinary Glc-Gal-Pyd and the severity of K&L grade, joint space narrowing, and osteophytes scores, which persisted after adjustment for age and BMI. No associations between the presence and severity of knee OA were found for serum CTX-I or serum osteocalcin. CONCLUSIONS: Urinary CTX-II and Glc-Gal-Pyd, but not systemic markers of bone turnover, are strongly associated with disease severity and the presence of OA at the tibiofemoral and patellofemoral joints in men.