Publications (6)11.69 Total impact
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Article: Osteoporosis and metabolic syndrome according to socio-economic status; contribution of PTH, Vitamin D and body weight: The Canarian Osteoporosis Poverty Study (COPS).
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ABSTRACT: BACKGROUND: Poverty is associated with a great number of diseases, but the prevalence of vitamin D deficiency, secondary hyperparathyroidism and the potential association of osteoporosis, osteoporotic fractures and metabolic syndrome in this situation are less well known. OBJECTIVE: To evaluate the associations between poverty, bone density, fragility fractures and metabolic syndrome in a population of southern-European postmenopausal women. Also, to assess the potential role of vitamin D and PTH levels in these associations. METHOD: Cross sectional study, carried out in 1,250 postmenopausal Caucasian Spanish women. The socio-economic status of the participants was determined after a personal interview, according to the criteria of the Spanish Institute of Statistics. Participants were divided into two socioeconomic levels: low (poverty), and medium or high. The study protocol included a health questionnaire, a complete physical examination, lateral radiograph of the dorsal and lumbar spine, and measurement of bone mineral density (BMD) at the lumbar spine (L2-L4) and proximal femur. Fasting blood was obtained to measure 25 hydroxy-vitamin D (25-OHD), intact PTH, and selected biochemical variables. RESULTS: Low socioeconomic status was associated with 25-OHD insufficiency, higher values of PTH, higher bodyweight and body mass index (BMI), lower values of BMD at the lumbar spine and a higher prevalence of fragility fractures, both vertebral and non-vertebral. Poverty was also associated with higher prevalence of metabolic syndrome, but this association was driven mainly by the higher BMI and not by poverty itself. Both vitamin D insufficiency and elevated PTH were consistently related to poverty and osteoporotic fractures. CONCLUSIONS: Poor postmenopausal women in southern Europe have a high prevalence of metabolic syndrome and osteoporotic fractures. Poverty was associated with higher BMI and metabolic syndrome on the one hand and, on the other, with 25OHD insufficiency, higher PTH levels and osteoporosis. 25OHD insufficiency and/or secondary hyperparathyroidism do not have a significant influence on the presence of metabolic syndrome in this population. © 2012 Blackwell Publishing Ltd.Clinical Endocrinology 09/2012; · 3.17 Impact Factor -
Article: Discriminative ability of heel quantitative ultrasound in postmenopausal women with prevalent vertebral fractures: application of optimal threshold cutoff values using classification and regression tree models.
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ABSTRACT: Quantitative ultrasound (QUS) of the heel has been proposed as a screening tool to evaluate the bone status and risk of osteoporotic fragility fractures. The aim of this study was to define threshold values that would maximize the predictive ability of QUS to discriminate subjects with vertebral fractures using the classification and regression trees (CART) models. A cross-sectional analysis was made of a cohort of 1,132 postmenopausal women with a mean age of 58 years. A total of 205 women (18.1 %) presented with a history of vertebral fracture. For all patients, a questionnaire of osteoporosis risk factors was given and measurements of the heel QUS and bone mineral density at the lumbar spine and the proximal femur, obtained by dual-energy X-ray absorptiometry (DXA), were made. Spinal radiographs were assessed for vertebral fractures. Sensitivity, specificity, predictive values, likelihood ratios, and receiver operator characteristics (ROC) curve QUS values were calculated using the optimal threshold identified in the CART models. Cutoff values calculated from best CART model (i.e., a QUS index >90.5 %) yielded a sensitivity of 80.3 % (95 % CI 69.2-88.1), a negative predictive value of 94 % (95 % CI 90.1-96.5), and a specificity of 68.8 % (95 % CI 63.3-73.8). This cutoff value would obviate the need to perform DXA in 32.8 % of the women of our population at risk for vertebral fractures. The area under the ROC curve of the best model was 0.8071. QUS was shown to discriminate between women with and without a history of vertebral fracture and constitutes a useful tool for assessing vertebral fracture risk. The application of decision trees (CART analyses) was helpful to define the optimal threshold QUS values.Calcified Tissue International 07/2012; 91(2):114-20. · 2.38 Impact Factor -
Article: Beta-blocker use is associated with fragility fractures in postmenopausal women with coronary heart disease.
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ABSTRACT: An association between cardiovascular disease and osteoporosis is described. A number of drugs often used by patients with coronary heart disease, such as thiazides, statins and beta-blockers, have shown controversial effects on bone. 1) To study the possible association between coronary heart disease (CHD) and bone mass density (BMD), quantitative ultrasound measurements (QUS) and the prevalence of fragility and vertebral fractures. 2) To study the possible influence of a number of drugs, statins, thiazides and beta-blockers, on BMD and fractures. Case-control study performed on 74 postmenopausal women who had recently suffered from CHD, and 111 age-matched controls. BMD was measured by Dual X-Ray Absorptiometry (DXA) at the lumbar spine and proximal femur. Quantitative Ultrasound (QUS) was also measured at the heel. Vertebral fractures were diagnosed by lateral, thoracic and lumbar X-rays. The occurrence of non-vertebral fractures was determined by examination of medical records. Patients with CHD had higher values of BMI. They had a higher prevalence of arterial hypertension and hyperlipidemia, and consequently higher consumption of beta-blockers and statins, but not of thiazides, and had lower alcohol consumption. Patients with CHD had higher BMD values, measured by DXA at the proximal femur, than controls, but there were no differences in DXA values at the lumbar spine or QUS at the heel between the two groups. The prevalence of all fragility factures was slightly higher in patients with CHD, but not to a significant extent. The prevalence of vertebral fractures was similar in the two groups. In a logistic analysis to identify factors associated with all fractures, beta-blockers were positively associated with fragility fractures, and DXA at the femoral neck was inversely associated with fragility fractures. Postmenopausal women with CHD have higher values of BMD at the proximal femur but, despite this, show a slight but non-significant increase in the prevalence of fragility fractures. Beta-blockers are independently associated with fragility fractures, but thiazides and statins are not.Aging clinical and experimental research 05/2010; 23(2):112-7. · 1.55 Impact Factor -
Article: Serum lipids and estrogen receptor gene polymorphisms in male-to-female transsexuals: effects of estrogen treatment.
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ABSTRACT: The effects of chronic administration of estrogens on the lipid profile in males are not fully understood. We have studied the effect of chronic administration of estrogens on the lipid profile in a group of transsexual (TS) Canarian men who were taking estrogens and anti-androgens for a minimum of 3 years. In this cross-sectional study of cases (n=27) and controls (n=26), plasma lipid profile and selected biochemical and hormonal features were studied. TS subjects had shorter stature than controls, and, after adjusting for height and weight, we found that they had lower values of serum free testosterone (FT) and higher estradiol (E2) levels than controls. The TS group had lower total and low-density lipoprotein (LDL) cholesterol and lower apoprotein B (Apo B) levels than the control group. Biochemistry was similar in both groups. The distribution of estrogen receptor gene polymorphisms (ER-Pvu and ER-Xba) was also similar in both groups. Serum Apo B concentration was related to ER-Xba polymorphism. No other association between lipid profile and the distribution of ER-Pvu and ER-Xba was found. We conclude that the chronic administration of estrogens in men could produce an increase in serum estradiol, a decrease in free testosterone levels, and a reduction in total cholesterol, LDL-cholesterol, and Apo B levels. The ER-Xba polymorphism may influence the Apo B response to exogenous estrogen in males.European Journal of Internal Medicine 08/2004; 15(4):231-237. · 2.00 Impact Factor -
Article: Bone mass, bone turnover, vitamin D, and estrogen receptor gene polymorphisms in male to female transsexuals: effects of estrogenic treatment on bone metabolism of the male.
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ABSTRACT: The effect of chronic administration of estrogens on bone and mineral metabolism in men is not known. We have studied the effect of chronic administration of estrogens on bone mineral metabolism in a group of transsexual (TS) Canarian men, who were taking estrogens for a minimum of 3 years. This is a cross-sectional study of cases and controls and we studied biochemical markers of bone remodeling, bone mineral density (BMD), and selected biochemical and hormonal features. TS subjects had shorter stature than controls, and after adjusting for height and weight, we found that they had lower values for serum-free testosterone and higher values for BMD, both in the lumbar spine and in femoral neck. Biochemistry, bone remodeling markers, and calcitropic hormone values were similar in both groups. Finally, the distributions of vitamin D receptor (BsmI) and estrogen receptor (ER-Pvu and ER-Xba) polymorphisms were also similar in both groups. We conclude that the chronic administration of estrogens in men may produce an increase in serum estradiol, a decrease in free testosterone levels, and an increase in BMD-both in lumbar spine and in femoral neck. We found no association between the transsexual phenotype and the distribution of vitamin D receptor (BsmI) and estrogen receptor (ER-Pvu and ER-Xba).Journal of Clinical Densitometry 02/2003; 6(3):297-304. · 1.29 Impact Factor -
Article: Discriminative ability of heel quantitative ultrasound in postmenopausal women with prevalent low-trauma fractures: application of optimal threshold cutoff values using CART models.
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ABSTRACT: Quantitative ultrasound (QUS) of the heel has been proposed as a screening tool to evaluate the bone status and risk of osteoporotic fragility fractures. The aim of this study was to define threshold values of QUS that would maximize the predictive ability of this technique to discriminate subjects with fragility fractures. A cross-sectional analysis was made of a cohort of 1132 postmenopausal women with a mean age of 58 yr. A total of 361 women (31.9%) presented with a history of osteoporotic fracture. Most fractures (74.1%) were nonvertebral. For all patients, a questionnaire of osteoporosis risk factors and measurements of the heel QUS and bone mineral density at the lumbar spine and the proximal femur obtained by dual-energy X-ray absorptiometry (DXA) were assessed. Spinal radiographs were assessed for fractures and historical nonvertebral fragility fractures. Sensitivity, specificity, predictive values, likelihood ratios, and receiver operator characteristic (ROC) curve QUS values were calculated using the optimal threshold identified in the classification and regression trees (CART) models. Cutoff values calculated from the best CART model (i.e., a quantitative ultrasound index (QUI) greater than 88.5% in women aged 58 yr or older) yielded 88.8% (95% confidence interval [CI]: 81.4-93.5) for sensitivity, a negative predictive value of 93.8 (95% CI: 89.4-96.4), and 70.4% (95% CI: 64.6-75.7) for specificity. This cutoff value would obviate the need to perform DXA in 43.1% of the population. The area under the ROC curve of the best model was 0.8363 (95% CI: 0.8249-0.8477). In conclusion, QUS was shown to discriminate between women with and without a history of fragility fracture and constitutes a useful tool for assessing fracture risk. The application of decision trees (CART analyses) was helpful to define the optimal threshold QUS values.Journal of Clinical Densitometry 14(4):492-8. · 1.29 Impact Factor
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2012
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Universidad de Las Palmas de Gran Canaria
Las Palmas de Gran Canaria, Canary Islands, Spain
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