Relación entre los niveles de hormonas sexuales en varones por encima de los 50 años y composición corporal, calidad ósea y calidad de vida / Relationships between Sex Hormone Levels in Men over 50 Years of Age and Body Composition, Bone Quality, and Quality of Life

Objetivo: Determinar la relación existente entre los niveles de hormonas sexuales y la composición corporal, la salud ósea y la calidad de vida en hombres por encima de los 50 años. Material y métodos: Estudio transversal en el que se incluyen 230 pacientes. Se determina la composición corporal utilizando parámetros antropométricos directos como el peso, la talla, la circunferencia de la cintura, la circunferencia del brazo dominante, el pliegue cutáneo tricipital, el pliegue en brazo dominante y el pliegue subcapsular. Se calculan parámetros antropométricos indirectos. Se realizan medidas cuantitativas de densidad ósea mediante ecografía del calcáneo, así como marcadores de recambio óseo (N-telopéptidos de excreción urinaria y relación calcio/ creatina). La calidad de vida se evalúa mediante el cuestionario abreviado de calidad de vida SF-36. Los análisis sanguíneos incluyen la determinación de testosterona total, globulina transportadora de hormonas sexuales (SHBG), testosterona libre calculada (TLc), sulfato de dehidroepiandrosterona (S-DHEA), androsteriona, 17-β-estradiol y gonadotropinas. Resultados: La TLc se asocia con un incremento muscular y una disminución del contenido graso, aun ajustándolo por edad (p<0,05). La densidad ósea sólo se relaciona con los niveles de estradiol y su fracción biodisponible (p<0,05). El S-DHEA y la TLc están asociadas a algunas subescalas del SF-36 (p<0,05). Conclusiones: La TLc es la hormona que mejor se relaciona con los cambios corporales asociados a la edad; sin embargo, los niveles de andrógenos no están asociados a la densidad ósea. Un descenso en la TLc y el S-DHEA podría estar relacionado con un descenso en la calidad de vida (AU)

Objetive: To determine whether there was a relationship between sex hormone levels and body composition, bone health, and health-related quality of life in men over 50 years of age. Material and methods: Transversal study carried out in 230 Spanish male outpatients. Body composition was studied using direct anthropometric measures: height, weight, waistline circumference, dominant arm circumference, tricipital skinfold, dominant arm skinfold, subscapular skinfold. Calculated anthropometric parameters were obtained. Quantitative ultrasound measurements of the calcaneus were performed and bone turnover markers were determined (N-telopeptides urinary excretion and calcium/creatinine urinary rate). Quality of life was studied using the short form 36 questionnaire (SF-36). Blood tests included total testosterone, sex hormone binding-globulin, calculated free testosterone (cFT), dehydroepiandrosterone sulphate (DHEA-S), androstenedione, 17-β-estradiol and gonadotrophins. Results: cFT was associated with increased muscle and to decreased in fat content, even after adjusting for age (p<0.05). Bone density was only related to estradiol and its bioavailable fraction (p<0.05). DHEA-S and cFT were related (p<0.05) to some SF-36 subscales. Conclusions: cFT level is most associated with body changes that accompany aging. Androgen levels are not related to bone density. Decline in cFT and DHEA-s levels might be related to decreased quality of life (AU)

[Relationships between sex hormone levels in men over 50 years of age and body composition, bone quality, and quality of life]. / Relación entre los niveles de hormonas sexuales en varones por encima de los 50 años y composición corporal, calidad ósea y calidad de vida.

OBJECTIVE: To determine whether there was a relationship between sex hormone levels and body composition, bone health, and health-related quality of life in men over 50 years of age. MATERIAL AND METHODS: Transversal study carried out in 230 Spanish male outpatients. Body composition was studied using direct anthropometric measures: height, weight, waistline circumference, dominant arm circumference, tricipital skinfold, dominant arm skinfold, subscapular skinfold. Calculated anthropometric parameters were obtained. Quantitative ultrasound measurements of the calcaneus were performed and bone turnover markers were determined (N-telopeptides urinary excretion and calcium/creatinine urinary rate). Quality of life was studied using the short form 36 questionnaire (SF-36). Blood tests included total testosterone, sex hormone binding-globulin, calculated free testosterone (cFT), dehydroepiandrosterone sulphate (DHEA-S), androstenedione, 17-ß-estradiol and gonadotrophins. RESULTS: cFT was associated with increased muscle and to decreased in fat content, even after adjusting for age (p<0.05). Bone density was only related to estradiol and its bioavailable fraction (p<0.05). DHEA-S and cFT were related (p<0.05) to some SF-36 subscales. CONCLUSIONS: cFT level is most associated with body changes that accompany aging. Androgen levels are not related to bone density. Decline in cFT and DHEA-s levels might be related to decreased quality of life.

[Changes in sexual hormones in a male population over 50 years of age. Frequency of low testosterone levels and risk factors]. / Cambios en las hormonas sexuales en varones mayores de 50 años. Prevalencia de niveles bajos de testosterona y factores de riesgo.

OBJECTIVES: To investigate the changes in sexual hormones in a selected male population older than 50 years of age. To assess the frequency of biochemical hypogonadism and which factors are related to testosterone levels. PATIENTS AND METHODS: A Cross-sectional study was carried out on 230 Spanish men older than 50 years of age. Blood tests were performed including: total testosterone, SHBG, calculated free testosterone, dehidroepiandrosterone sulfate, androstendione, estradiol, bioavailable estradiol, FSH, LH, and prolactin. Clinical and socio-demographic backgrounds were investigated. The frequency of biochemical hypogonadism was established using total and free testosterone levels as diagnostic criteria. Factors that may influence testosterone levels were evaluated by univariate and multivariate statistical analysis, and a logistic regression model was used to determine which factors can predict biochemical hypogonadism according to free testosterone levels. RESULTS: Age was associated with a significant decrease (p < 0.05) in total testosterone (0.6% per year), free testosterone (1.3% per year), dehydroepiandrosterone sulfate (1.8% per year) and bioavailable estradiol (0.69% per year). Moreover, an increase in SHBG, LH, and FSH was observed (p < 0.05). According to total testosterone levels, 4.8% of the men were hypogonadal, whereas 24.8% were hypogonadal when free testosterone was considered. In the univariate analysis, obesity, diabetes mellitus and hyperlipemia were related to lower total testosterone levels, while free testosterone levels were lower in men with sedentary life, lower levels of education, obesity or diabetes mellitus. In the multivariate analysis age, diabetes mellitus and obesity were inversely related to total and free testosterone levels. Free testosterone was also inversely related to hyperlipemia. For biochemical hypogonadism, simple logistic regression analysis selected age, sedentary life, obesity and diabetes mellitus. In the multivariate analysis age, obesity and diabetes mellitus had significant independent prognostic value. CONCLUSIONS: Starting from 50 years of age, a significant age-related decrease in total testosterone, free testosterone, dehydroepiandrosterone sulfate and bioavailable estradiol is observed. The frequency of biochemical hypogonadism is higher when free testosterone levels are used for diagnosis. Total testosterone levels were related to age, diabetes mellitus and obesity. Free testosterone was related to age. diabetes mellitus, obesity and hyperlipemia. The probability of suffering low free testosterone levels increases with age, diabetes mellitus and/or obesity.

Cambios en las hormonas sexuales en varones mayores de 50 años. Prevalencia de niveles bajos de testosterona y factores de riesgo / Changes in sexual hormones in a male population over 50 years of age. Frequency of low testosterone levels and risk factors

Objetivos: Evaluar los cambios en las hormonas sexuales en una población masculina mayor de 50 años, conocer la frecuencia de hipogonadismo bioquímico y qué factores se relacionan con los niveles de testosterona. Pacientes y método: Estudio transversal en 230 varones sanos mayores de 50 años. Se realizaron determinaciones de testosterona total, testosterona libre, testosterona biodisponible, sulfato de de hidroepiandrosterona, estradiol total y biodisponible, LH, FSH y prolactina y se averiguaron los antecedentes clínicos y sociodemográficos. Determinamos la frecuencia de hipogonadismo bioquímico. Analizamos los factores que podían influir en los niveles de testosterona total y libre mediante análisis uni y multivariante y realizamos un análisis de regresión logística para conocer los factores que pueden predecir el hipogonadismo bioquímico en base a la testosterona libre. Resultados: A medida que incrementa la edad de los sujetos evaluados, se observan niveles significativamente más bajos (p<0,05) de los niveles de testosterona total (0,6% anual), testosterona libre (1,3% anual), sulfato de de hidroepiandrosterona (1,8% anual) y estradiol biodisponible (0,69% anual), mientras que se observó un incremento de la SHBG, la LH y la FSH (p>0,05).La prevalencia de niveles bajos de testosterona total fue del 4,8%, alcanzando el 24,8% cuando utilizamos como referencia la testosterona libre. La media de los niveles plasmáticos de testosterona total fue significativamente inferior en los varones con obesidad, diabetes mellitus o dislipemia, mientras que la de los niveles de testosterona libre fue menor en aquellos con estilo de vida sedentario, bajo nivel de estudios, obesos o con diabetes mellitus. En el análisis multivariante, la edad, la diabetes y la obesidad se relacionaron inversamente con los niveles de testosterona total. Con la testosterona libre se relacionan los mismos factores además de la dislipemia. En el análisis de regresión logística multivariante para el hipogonadismo bioquímico, la edad, la obesidad y la diabetes fueron las variables con valor predictivo independiente. Conclusión: A partir de los 50 años se produce un descenso significativo de testosterona total, testosterona libre, sulfato de de hidroepiandrosterona y estradiol biodisponible relacionado con la edad. La prevalencia de hipogonadismo bioquímico es mayor si utilizamos la testosterona libre. Los niveles de testosterona total se relacionan además de con la edad, con la diabetes y la obesidad, añadiéndose la dislipemia para la testosterona libre. La probabilidad presentar niveles bajos de testosterona libre aumenta con la edad y es mayor cuando existen antecedentes de diabetes mellitus y/u obesidad (AU)

Objectives: To investigate the changes in sexual hormones in a selected male population older than 50 years of age. To assess the frequency of biochemical hypogonadism and which factors are related to testosterone levels. Patients and methods: A Cross-sectional study was carried out on 230 Spanish men older than 50 years of age. Blood tests were performed including: total testosterone, SHBG, calculated free testosterone, dehidroepiandrosterone sulfate, androstendione, estradiol, bioavailable estradiol, FSH, LH, and prolactin. Clinical and socio-demographic backgrounds were investigated. The frequency of biochemical hypogonadism was established using total and free testosterone levels as diagnostic criteria. Factors that may influence testosterone levels were evaluated by univariate and multivariate statistical analysis, and a logistic regression model was used to determine which factors can predict biochemical hypogonadism according to free testosterone levels. Results: Age was associated with a significant decrease (p<0.05) in total testosterone (0.6% per year), free testosterone (1.3% per year),dehidroepiandrosterone sulfate (1.8% per year) and bioavailable estradiol (0.69% per year). Moreover, an increase in SHBG, LH, and FSH was observed (p<0.05). According to total testosterone levels, 4.8% of the men were hypogonadal, whereas 24.8% were hypogonadal when free testosterone was considered. In the univariate analysis, obesity, diabetes mellitus and hyperlipemia were related to lower total testosterone levels, while free testosterone levels were lower in men with sedentary life, lower levels of education, obesity or diabetes mellitus. In the multivariate analysis age, diabetes mellitus and obesity were inversely related to total and free testosterone levels. Free testosterone was also inversely related to hyperlipemia. For biochemical hypogonadism, simple logistic regression analysis selected age, sedentary life, obesity and diabetes mellitus. In the multivariate analysis age, obesity and diabetes mellitus had significant independent prognostic value. Conclusions: Starting from 50 years of age, a significant age-related decrease in total testosterone, free testosterone, dehidroepiandrosterone sulfate and bioavailable estradiol is observed. The frequency of biochemical hypogonadism is higher when free testosterone levels are used for diagnosis. Total testosterone levels were related to age, diabetes mellitus and obesity. Free testosterone was related to age, diabetes mellitus, obesity and hyperlipemia. The probability of suffering low free testosterone levels increases with age, diabetes mellitus and/or obesity (AU)

[Evaluation of an immunoassay kit to measure free testosterone]. / Evaluación de una técnica de inmunoanálisis para la determinación de testosterona libre.

INTRODUCTION AND OBJECTIVES: The best indicators to the diagnosis of hypogonadism are free and bioavailable testosterone circulating levels. Free and bioavailable testosterone measurements are complex. However, simple kits for direct measurement of free testosterone by analog immunoassay are available. We examined the utility of an enzymoimmunoassay kit for free testosterone measurement. MATERIAL AND METHOD: One hundred thirty-three healthy males were included. Total testosterone, SHBG, albumin and free testosterone was measured. We used two different methods to free testosterone estimation: direct measurement by enzymoimmunoassay and mathematical calculation with Vermeulen's formula, which uses albumin concentration, total testosterone and SHBG to calculate free testosterone (method recommended by the International Society for the Study of the Aging Male). We compared the two methods means values and a linear regression study was performed. RESULTS: Mean age was 37 +/- 11 years. Mean serum concentration for total testosterone was 21.43 +/- 6.8 nm ol/L. The mean value for free testosterone measured by direct and mathematical method was 0.0508 +/- 0.0118 nmol/L and 0.474 +/- 0.123 nmol/L respectively. In linear regression study exists a positive correlation between both methods (p< 0.05), although correlation coefficient is very low (r = 0.25). CONCLUSIONS: There are significant statistical differences between the measurements of free testosterone by direct and mathematical methods. Although certain correlation is observed, this is very low. In conclusion, free testosterone measurement by enzymoimmunoassay is not reliable.

Evaluación de una técnica de inmunoanálisis para la determinación de testosterona libre / Evaluation of an immunoassay kit to measure free testosterone

Introducción y objetivos: Los mejores indicadores bioquímicos para el diagnóstico del hipogonadismo son la testosterona libre y la biodisponible. La determinación de ambas fracciones de testosterona es compleja, aunque se han desarrollado técnicas de inmunoanálisis que permiten la determinación de la testosterona libre de manera directa y sencilla. Valoramos la utilidad de una técnica no evaluada de enzimoinmunoanálisis para la determinación de testosterona libre. Material y métodos: En el estudio se incluyeron 133 varones sanos en los que se determinó la testosterona total, la SHBG, la albúmina y la testosterona libre. La testosterona libre fue determinada mediante 2 métodos diferentes: determinación directa mediante enzimoinmunoanálisis (DSL 10-49100 ACTIVE(R) Free Testosterone EIA, Diagnostics System Laboratories) y mediante cálculo matemático utilizando la fórmula desarrollada por Vermeulen, que utiliza la concentración de albúmina, testosterona total y SHBG para calcular la testosterona libre (método recomendado por la 'International Society for the Study of the Aging Male'). Comparamos los valores obtenidos mediante un test de comparación de medias y realizamos un análisis de regresión para observar el grado de correlación existente entre ambos tipos de determinaciones. Resultados: La edad media fue de 37 ± 11 años. Los niveles medios de testosterona total fue de 21,43 ± 6,8 nmol/L y los de testosterona libre de 0,0508 ± 0,0118 nmol/L para el método directo y de 0,474 ± 0,123 nmol/L para el método matemático (p<0,05). En el estudio de regresión lineal se observa que aunque existe una correlación positiva entre ambos métodos (p<0,05) el coeficiente de correlación es bajo (r = 0,25). Conclusiones: Existen diferencias significativas entre los valores de testosterona libre determinados por el método directo de enzimoinmunoanálisis y la testosterona libre calculada. Aunque se observa una cierta correlación, esta es tan baja que hace poco fiable la utilización del enzimoinmunoanálisis para la determinación de la testosterona libre

Introduction and objetives: The best indicators to the diagnosis of hypogonadism are free and bioavailable testosterone circulating levels. Free and bioavailable testosterone measurements are complex. However, simple kits for direct measurement of free testosterone by analog immunoassay are available. We examined the utility of an enzymoimmunoassay kit for free testosterone measurement. Material and method: One hundred thirty-three healthy males were included. Total testosterone, SHBG, albumin and free testosterone was measured. We used two different methods to free testosterone estimation: direct measurement by enzymoimmunoassay and mathematical calculation with Vermeulen’s formula, which uses albumin concentration, total testosterone and SHBG to calculate free testosterone (method recommended by the International Society for the Study of the Aging Male). We compared the two methods means values and a linear regression study was performed. Results: Mean age was 37 ± 11 years. Mean serum concentration for total testosterone was 21.43 ± 6.8 nm ol/L. The mean value for free testosterone measured by direct and mathematical method was 0.0508 ± 0.0118 nmol/L and 0.474±0.123 nmol/L respectively. In linear regression study exists a positive correlation between both methods (p< 0.05), although correlation coefficient is very low (r = 0.25). Conclusions: There are significant statistical differences between the measurements of free testosterone by direct and mathematical methods. Although certain correlation is observed, this is very low. In conclusion, free testosterone measurement by enzymoimmunoassay is not reliable