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J San Martin

Publications and source records attributed to J San Martin.

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Severity of vertebral fracture reflects deterioration of bone microarchitecture.

INTRODUCTION: Bone microarchitecture, a component of bone strength, is generally measured on transiliac bone biopsy samples. The objective of this study was to determine whether assessment of four grades of vertebral fracture severity could serve as a noninvasive surrogate marker for trabecular bone volume and microarchitecture. METHODS: Baseline vertebral fracture severity was determined by semiquantitative assessment of spine radiographs from 190 postmenopausal women with osteoporosis. Bone-structure indices were obtained by 2D histomorphometry and 3D microcomputed tomography (CT) analyses. Significance of differences was determined after adjusting for age, height, and lumbar spine bone mineral density. RESULTS: There were significant (P < 0.05) trends in decreasing bone volume, trabecular number, and connectivity, and increasing trabecular separation with greater vertebral fracture severity. Histomorphometric bone volume was 25 and 36% lower (P < 0.05) in women with moderate and severe fractures than in women with no fractures, respectively. Compared with women without fractures, women with mild, moderate, and severe fractures had lower (P < 0.05) microCT bone volume (23, 30, and 51%, respectively). CONCLUSIONS: Microarchitectural deterioration was progressively worse in women with increasing severity of vertebral fractures. We conclude that assessment of vertebral fracture severity is an important clinical tool to evaluate the severity of postmenopausal osteoporosis.

Aged↗

Teriparatide effects on vertebral fractures and bone mineral density in men with osteoporosis: treatment and discontinuation of therapy.

Teriparatide (rhPTH[1-34]), a bone-forming agent for the treatment of osteoporosis, increases bone mineral density in men and women, and reduces the risk of fractures in women with osteoporosis. However, fracture efficacy has not yet been confirmed in men. Further, there is limited information on the effect of withdrawal of teriparatide. The purpose of this manuscript is to report on bone mineral density and vertebral fracture incidence during a 42-month observation period, from the baseline of the previously reported treatment study in men [1] through 30 months of posttreatment follow-up. Three hundred fifty-five men who were treated with once-daily self-injections of either placebo or 20 or 40 microg of teriparatide participated in the follow-up study. Bone mineral density gradually decreased following discontinuation of teriparatide therapy. However, the lumbar spine and total hip values remained significantly higher than baseline after 30 months of follow-up (p< or =0.001). Antiresorptive treatment prevented the decline and tended to further increase bone mineral density. Lateral thoracic lumbar radiographs obtained at baseline and 18 months after discontinuation of teriparatide were available for 279 men. Of these men, 11.7% assigned to placebo, 5.4% treated with teriparatide 20 microg, and 6.0% treated with teriparatide 40 microg had an incident vertebral fracture. In the combined teriparatide treated groups vs placebo, the risk of vertebral fracture was reduced 51% (nonsignificant, p=0.07). The incidence of moderate or severe fractures was significantly reduced by 83% (p=0.01). In conclusion, men who received teriparatide and who may have received follow-up antiresorptive therapy had a decreased risk of moderate and severe vertebral fractures.

Adult↗

Digitized mammography: a clinical trial of postmenopausal women randomly assigned to receive raloxifene, estrogen, or placebo.

BACKGROUND: High mammographic density is associated with increased breast cancer risk. Previous studies have shown that estrogens increase breast density on mammograms, but the effect on mammographic density of selective estrogen receptor modulators, such as raloxifene, is unknown. We assessed changes in mammographic density among women receiving placebo, raloxifene, or conjugated equine estrogens in an osteoporosis prevention trial. METHODS: In a 5-year multicenter, double-blind, randomized, placebo-controlled osteoporosis prevention trial, healthy postmenopausal women who had undergone hysterectomy less than 15 years before the study and had no history of breast cancer received placebo, raloxifene (at one of two doses), or conjugated estrogens (ERT). Women from English-speaking investigative sites who had baseline and 2-year craniocaudal mammograms with comparable positioning (n = 168) were eligible for this analysis. Changes in mammographic density were determined by digital scanning and computer-assisted segmentation of mammograms and were analyzed with the use of analysis of variance. All statistical tests were two-sided. RESULTS: Among the four treatment groups after 2 years on study, the mean breast density (craniocaudal view) was statistically significantly greater in the ERT group than it was in the other three groups (P<0.01 for all three comparisons). Within treatment groups, the mean breast density from baseline to 2 years decreased statistically significantly in women receiving the placebo or either the higher or lower raloxifene dose (P = 0.003, P = 0.002, and P<0.001, respectively) and showed a nonstatistically significant increase in women receiving ERT. CONCLUSIONS: In an osteoporosis prevention trial, raloxifene did not increase breast density after 2 years of treatment. Raloxifene administration should not interfere with, and could even enhance, mammographic detection of new breast cancers.

Breast↗

Correlation between antibodies to type II collagen and treatment outcome in bilateral progressive sensorineural hearing loss.

Our aim was to assess whether "idiopathic" bilateral progressive sensorineural hearing loss (BPSHL) has an immunological cause in some patients; antibodies to native type II collagen were sought by an ELISA in eighteen patients with BPSHL, before and after corticosteroid treatment, and in twelve patients with Menière's disease, fifteen with otosclerosis, eighteen with rheumatoid arthritis, nine with fibrositis, and nine healthy controls. A positive result was defined as a mean dilution titre of 2 or more. Eight of eighteen BPSHL patients had positive titres--significantly (p less than 0.005) more than in any other group (one Menière's disease, two otosclerosis, and no others). The mean antibody titre was higher in the BPSHL group than in any other group (2.02 [SEM 0.62] vs 0.17 [0.17]) Menière's disease, 0.44 [0.32] otosclerosis, 0 all others; p less than 0.005). The nine BPSHL patients who showed a clinical response to corticosteroids (improvement in at least one tone by audiogram or 25 db in speech discrimination score) had the highest mean antibody titre (3.46 [0.88] vs 0.59 [0.59] for the nine non-responsive patients; p less than 0.04). We suggest that in some patients with BPSHL, immunity to type II collagen, a major constituent of the inner ear, may be important in the pathogenesis of the disorder.

Antibodies↗

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Argentina↗