Prospective trial of ossein-hydroxyapatite compound in surgically induced postmenopausal women.

Women with increased bone resorption induced by bilateral oophorectomy 1-5 years previously (of a total of 48 women in the study, 20 were controls, and 28 were the treatment group) were studied during a 3 year follow-up. The ossein-hydroxyapatite compound (OHC) treatment provided 1.6 g calcium, 0.74 g phosphorus and 1.94 g noncollagen peptides a day. Biochemical indices of bone remodeling (urinary hydroxyproline/creatinine and calcium/creatinine ratios, bone alkaline phosphatase isoenzyme in serum and plasma tartrate resistant acid phosphatase) decreased significantly in both treatment and control groups compared with their baseline values. Biochemical indices were significantly lower in the treatment group compared to the controls after the first year, but in only half the patients after three years. By the third year these responders had significantly higher cortical area than controls. In an additional 13 women a transient response to OHC was followed by an accelerated bone loss and a return to the control values of the biochemical indices of bone resorption. In the poor responders an estrogen/progesterone substitution resulted within 6 months in a complete normalization in the biochemical parameters and in no further cortical bone loss. The results confirm a heterogeneous pattern of bone mass loss in menopause and indicate that OHC treatment is of value in preventing cortical bone loss in a portion of at-risk postmenopausal women, provided that the efficacy of the treatment is monitored.