Cartilage turnover assessed with a newly developed assay measuring collagen type II degradation products: influence of age, sex, menopause, hormone replacement therapy, and body mass index

Background: Cartilage normally has a slow turnover but in arthritis increased metabolism results in degradation of the tissue. Objective: To assess cartilage turnover in a sample of the general population by an assay measuring cartilage derived urinary collagen type II (CTX-II) C-telopeptide degradation products. Methods: CTX-II concentrations were measured in urine samples from 615 healthy men and women aged 20–87 years, and the influence of age, sex, menopause, hormone replacement therapy (HRT), and body mass index (BMI) was assessed. Results: CTX-II concentrations showed age dependent variations, with notable differences between men and women. Mean (SD) CTX-II concentration in postmenopausal women (220 (118) ng/mmol, n=25) was significantly higher than in an age matched group of premenopausal women (112 (79) ng/mmol, n=26, p