tUMAN STUDIE, ¢ Cyclic Oral Phosphate and Etidronate Increase Femoral and Lumbar Bone Mineral Density and Reduce Lumbar Spine Fracture Rate Over Three Years

We have performed a study of the safety and efficacy of cyclic sequential oral phosphate, diphosphonate and calcium carbonate. Forty-two postmenopausal women with osteopo-rosis diagnosed by dual-photon absorptiometry were treated with a sequential cyclic regimen of oral phosphate for 3 days, etidronate for 2 wk, and then a calcium salt for 12 wk. This was repeated cyclically for 3 yr. They were rescanned after every two 101-day cycles. A control group of 20 patient receiving only the calcium salt was matched for age, time since menopause, race and sex. The group treated with cyclic phosphate, etidronate, and calcium regimen had 80 % fewer fractures than the control group over 3 yr of follow-up. Sig-nificant response in halting bone mineral loss and increasing bone mineral density was seen in none of the controls but in 90 % of treated patients ' lumbar spine and 70%-80 % of the three regions of the femoral neck examined. J Nucl Med 1992; 33:1-5 Osteoporos i s is a disease characterized by the loss of bone mineral and has a high prevalence in postmenopausal white and Oriental females. The attendent morbidity and mortality and medical expenses related to this disorder are well documented (1). Osteoporosis has been categorized into two forms by the Mayo Clinic group, one with its onset in the peri-menopausal period, and the other in an older age group (2). The form beginning atmenopause has been success-fully prevented with estrogen and progestagen, although the effectiveness of hormone therapy on the older age group is less certain. Unopposed estrogenic therapy raises the risk of endometrial carcinoma (3) (and possibly breast carcinoma), although it decreases the probability of car