90072368 The effect of prolonged fluoride therapy for osteoporosis: Bone composition and histology

362 postmenopausal women. With respect to the type of menopause, the highest levels of both FVIIc and FVIIc/FVIIag ratio were found in women having undergone bilateral oophorectomy. These results suggest that raised factor VII coagulant activity may contribute to and increased risk of CHD in postmenopausal women. 90072367 A randomized study on the effects of estrogea/gestagen or high dose oral calcium on trabecular bone remodeling in postmenopausal osteoporosis Steiniche T.; Hasling C.; Charles P.; Eriksen E.F.; Mosekilde L.; Melsen F. Department of Endocrinology and University Institute of Phatology, Aarhus Amtssygehus, DK-So00 Aarhus C BONE 1989 10/S (313-320) Thirty-seven patients with postmenopausel crush fracture osteoporosis were randomized to oral cyclic estrogen/gestagen (n = 20) or oral calcium (2000 mg elemental calcium per day) (n = 17). Fourteen in each group completed 1 year of treatment. Iliac crest bone biopsies were obtained after intravital double labeling with tetracycline before and after treatment in 10 patients on estrogen/gestagen and 11 patients on calcium. In the estrogen/gestagen group the activation frequency in trabecular bone decreased from 0.52 + 0.11 @EM) year-’ to 0.27 + 0.08 year-’ (p < 0.01). No significant changes were found in resorption or formation periods. The osteoid surfaces and the mineralizing surfaces decreased (p < 0.05), whereas the decrease in eroded surfaces was insignificant. Furthermore, no significant changes were observed in final resorption depth, wall thickness or bone balance per remodeling cycle. Serum alkaline phosphatase and renal hydroxyproline excretion decreased during treatment (p < O.OOZ),whereas the lumbar bone mineral content (BMC) increased (p < 0.01). In the calcium group the extent and thickness of osteoid surfaces decreased (p < 0.05) without significant changes in activation frequency. Serum alkaline phosphatase and renal hydroxyproline excretion decreased during treatment (p < 0.02). No significant changes were observed in lumbar BMC or the other histomorphometric parameters. The study supports that the positive effect of estrogenigestagen on BMC can be explained by a reduction in the activation frequency of new remodeling cycles leading to a decreased remodeling space and an increase in mean bone age. There is no evidence of a positive balance per remodeling cycle. High dose calcium may improve osteoid mineralization, but there is no histomorphometric evidence of a significant reduction in activation frequency or a more positive balance per remodeling cycle. 90072368 The effect of prolonged fluoride therapy for osteoporosis: Bone composition and histology Lundy M.W.; Wergedal J.E.; Teubner E.; Burnell J.; Sherrard D; Baylink D.J. Department of Biochemistry, Loma Linda Vnivcersity, and Mineral Metabolism Unit. Jerry L. Pettis Memorial Veterans Hospital, Loma Linda, CA BONE 1989 IO/5 (321-327) To examine the long-term effects of fluoride therapy in osteoporosis, we obtained iliac crest biopsies from 11 osteoporotic patients 6 to 12 years after they had started fluoride therapy. Although basal biopsied were not obtained, nine subjects had been biopsied 4 years prior to the second biopsy. In addition, 4 subjects had stopped fluoride therapy prior to the second biopsy. Biopsy samples were divided and analyzed: (a) histomorphometrically for bone formation and mineralization; and (b) for mineral content. Parameters of bone formation were increased in the first biopsy of all patients; they remained elevated in the second biopsy of subjects still receiving fluoride, but decreased to normal values in subjects who stopped fluoride therapy. Parameters of mineralization (i.e., osteoid width and osteocytic osteoid) were elevated in the first biopsy, but had decreased in the second biopsy whether fluoride was stopped or not. There was no woven bone in these biopsies. Bone mineral content, whether measured as density or by summation of the individual ions (Oremineral), was higher than normal in all subjects, whether or not they were still receiving fluoride. These results suggest that prolonged fluoride therapy of osteoporosis continues to stimulate bone formation., but does not cause a progressive mineralization defect. Mineral content is acutely increased following fluoride therapy, and persists after therapy is discontinued.