A. Díez Pérez

La hormona paratiroidea en el tratamiento de la osteoporosis

Current treatments available for osteoporosis until recently were active by inhibiting osteoclast activity and, thus, reducing bone remodelling. Intact PTH (PTH 1-84) and its analog, teriparatida (human recombinant PTH 1-34), are a new class of anabolic treatment of osteoporosis. It has been described a positive effect on bone microarchitecture and a reduction of the risk of new fractures due to a bone-forming mechanism. PTH must be considered as an useful alternative in the treatment of severe osteoporosis, both in men and women, in patients with several osteoporosis-related fractures or with a very low bone mineral density (T-score below -3.5) an a high risk for fracture. Other potential uses are glucocorticoid-induced and other secondary osteoporosis. The use of PTH is not recommended for more than 18 months for teriparatida and 24 months for PTH 1-84.

Bone Health in Postmenopausal Women Treated with Adjuvant Aromatase Inhibitors for Early Breast Cancer: 12 Months Follow-Up.

Background: The use of aromatase inhibitors (AI) in the adjuvant setting for postmenopausal women with receptor-positive breast cancer is well established. The AI treatment has been associated with decline in bone mineral density (BMD), and increased bone turnover markers. We designed a prospective study to evaluate the effect of oral bisphosphonates (BP) on vertebral and non vertebral fractures (VF), bone turnover markers (bTM), BMD, and quality of life (QoL) in postmenopausal women receiving adjuvant AI for hormone receptor positive early breast cancer. Material and methods: Postmenopausal, receptor-positive breast cancer women treated with AI as initial therapy [Letrozol (LET)] or after 2 or 5 years of tamoxifen [switched to exemestane (EXE)] were included. Patients were stratified by lumbar spine, femoral neck and total hip BMD to receive open-label treatment with BP, alendronate or risedronate, (if osteoporosis [T-score -2.0 and no major risk factor). Levels of 25-OH vitamin D, N-telopeptide (NTx), bone alkaline phosphatase (bALP) and osteocalcin (OC) were measured at baseline, 3, 12 and 24 moths, and BMD and thoracic and lumbar spine X-rays were assesed at baseline, 1 and 2 years. QoL was evaluated by ECOS-16 questionnaire and a visual analogue scale used to evaluate arthralgia. Results: from 03/2006 to 03/2009, 261 patients have been included and 117 have completed >12 month follow up. All the bTM increased after 12 months of AI treatment and a significant decrease on BMD was also observed (Table 1). This effect is reverted with oral BP treatment, maintaining the BMD level and reducing the bTM. With the AI introduction QoL of patients became worse, and the BP treatment did not improve neither arthralgia nor bone pain. Osteoporotic fractures were recorded at baseline in 12.3% of women (4.2% VF and 7.7% non VF). Conclusions: AI treatment increased bone turnover, decreased BMD and QoL. Of note, BP use decreased bone turnover, has neutral effect in BMD and does not improve QoL. This study suggests that the current recommendation of the use of BP should be revisited to consider including all postmenopausal women treated with adjuvant AI to avoid increased bone turnover and bone mass decrease. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3175.

Protocolo de actuación ante la sospecha de fracaso terapéutico en la osteoporosis

The evaluation and monitoring of osteoporosis treatment are taken into account 3 factors: bone mineral density, markers of remodeling and the occurrence of fractures. Has recently been established, in order to facilitate clinical practice, the definition of treatment failure. Further studies to make decisions with greater confidence are needed.

Qué supone la calidad ósea en la osteoporosis

Concepto. La osteoporosis se caracteriza por una alteracion de la resistencia osea que predispone a las fracturas. La resistencia osea esta condicionada tanto por la cantidad (densidad mineral osea) como por la calidad osea. Factores condicionantes de la calidad osea. Se agrupan en: factores vinculantes a la arquitectura osea (geometria osea y microarquitectura osea) y factores intrinsecos del hueso (grado de mineralizacion, composicion de la matriz proteica y estado de la red osteocitaria). Remodelado oseo. El remodelado oseo condiciona la masa osea y la calidad del hueso. Existen marcadores bioquimicos del remodelado oseo, tanto de formacion como de resorcion osea. Metodos de medida de la calidad osea. Para valoracion de la microarquitectura disponemos de la histomorfometria, la resonancia magnetica nuclear, la microtomografia computarizada in vivo e in vitro y estudios biomecanicos in vitro.