Osteopenia in rheumatoid arthritis: a biochemical, hormonal and histomorphometric study

Abstract

To determine whether the osteopenia of rheumatoid arthritis (RA) is due to reduction of trabecular bone mass (TBV) and/or cortical width (CW), we evaluated these parameters by bone histomorphometry; we also measured the calciotropic hormones parathormone(PTH) and calcitonin (CT), vitamin D [25(OH)D] and the biological markers of bone remodeling in a group of patients with RA. Study subjects were divided into Group C - premenopausal patients, and Group A - menopausal patients and men of the same ages. These groups were compared to two age-matched control groups, B and D. In both A vs. B and C vs. D, TBV and CW were significantly lower in patients. There were no differences in PTH or CT, but 25(OH)D was significantly reduced, and BGP, OHP/Cr and AP were raised in patients. Patients also exhibited TBV loss in more than 55% and CW loss in more than 98%. These changes suggest that the decline in bone mass, mainly cortical, but also trabecular, is due to increased bone turnover and enhanced resorption and seem to reflect intrinsic alterations of RA.

Osteoporosis in Rheumatoid Arthritis: A Molecular Biological Aspect of Connective Tissue Gene Activation.

“…Metabolic changes such as the decrease of intestinal calcium absorption (Sambrook et al 1985a) Rico et al 1990) and reduced PTH secretion in response to lowered calcium (af Ekenstam et al 1990) exist in RA. There is a correlation between the initial increased levels of PTH and 1, 25dihydroxyvitamin D3 and subsequent bone loss in RA (Sambrook et al 1990).…”