To assess the relation between type I collagen degradation and the duration of rheumatoid arthritis (RA).
The serum concentrations of cross linked carboxyterminal telopeptide of type I collagen (ICTP) measured earlier in a community based series (90 patients) and a hospital based series (59 patients) were re-evaluated with reference to the duration of RA.
The serum ICTP showed a positive correlation with the duration of the disease in the hospital based series (r(s)=0.40, p<0.01) but not in the community based one (r(s)=0.18, p=0.10).
Type I collagen degradation predominantly reflecting pathological bone destruction does not seem to diminish in longlasting RA.