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1.
J Clin Endocrinol Metab ; 104(12): 6238-6246, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31504596

RESUMEN

CONTEXT: Prostate-specific antigen (PSA) changes during testosterone treatment of older hypogonadal men have not been rigorously evaluated. DESIGN: Double-blinded, placebo-controlled trial. SETTING: Twelve US academic medical centers. PARTICIPANTS: Seven hundred ninety hypogonadal men ≥65 years of age with average testosterone levels ≤275 ng/dL. Men at high risk for prostate cancer were excluded. INTERVENTIONS: Testosterone or placebo gel for 12 months. MAIN OUTCOMES: Percentile changes in PSA during testosterone treatment of 12 months. RESULTS: Testosterone treatment that increased testosterone levels from 232 ± 63 ng/dL to midnormal was associated with a small but substantially greater increase (P < 0.001) in PSA levels than placebo treatment. Serum PSA levels increased from 1.14 ± 0.86 ng/mL (mean ± SD) at baseline by 0.47 ± 1.1 ng/mL at 12 months in the testosterone group and from 1.25 ± 0.86 ng/mL by 0.06 ± 0.72 ng/mL in the placebo group. Five percent of men treated with testosterone had an increase ≥1.7 ng/mL and 2.5% of men had an increase of ≥3.4 ng/mL. A confirmed absolute PSA >4.0 ng/mL at 12 months was observed in 1.9% of men in the testosterone group and 0.3% in the placebo group. Four men were diagnosed with prostate cancer; two were Gleason 8. CONCLUSIONS: When hypogonadal older men with normal baseline PSA are treated with testosterone, 5% had an increase in PSA ≥1.7 ng/mL, and 2.5% had an increase ≥3.4 ng/mL.


Asunto(s)
Terapia de Reemplazo de Hormonas , Hipogonadismo/sangre , Hipogonadismo/tratamiento farmacológico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Testosterona/sangre , Testosterona/uso terapéutico , Anciano , Método Doble Ciego , Estudios de Seguimiento , Humanos , Hipogonadismo/complicaciones , Estudios Longitudinales , Masculino , Pronóstico , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/etiología
2.
J Am Soc Nephrol ; 30(5): 890-903, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31000566

RESUMEN

BACKGROUND: Data from clinical trials to inform practice in maintenance hemodialysis are limited. Incorporating randomized trials into dialysis clinical care delivery should help generate practice-guiding evidence, but the feasibility of this approach has not been established. METHODS: To develop approaches for embedding trials into routine delivery of maintenance hemodialysis, we performed a cluster-randomized, pragmatic trial demonstration project, the Time to Reduce Mortality in ESRD (TiME) trial, evaluating effects of session duration on mortality (primary outcome) and hospitalization rate. Dialysis facilities randomized to the intervention adopted a default session duration ≥4.25 hours (255 minutes) for incident patients; those randomized to usual care had no trial-driven approach to session duration. Implementation was highly centralized, with no on-site research personnel and complete reliance on clinically acquired data. We used multiple strategies to engage facility personnel and participating patients. RESULTS: The trial enrolled 7035 incident patients from 266 dialysis units. We discontinued the trial at a median follow-up of 1.1 years because of an inadequate between-group difference in session duration. For the primary analysis population (participants with estimated body water ≤42.5 L), mean session duration was 216 minutes for the intervention group and 207 minutes for the usual care group. We found no reduction in mortality or hospitalization rate for the intervention versus usual care. CONCLUSIONS: Although a highly pragmatic design allowed efficient enrollment, data acquisition, and monitoring, intervention uptake was insufficient to determine whether longer hemodialysis sessions improve outcomes. More effective strategies for engaging clinical personnel and patients are likely required to evaluate clinical trial interventions that are fully embedded in care delivery.


Asunto(s)
Causas de Muerte , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/terapia , Evaluación de Resultado en la Atención de Salud , Diálisis Renal/mortalidad , Diálisis Renal/métodos , Atención Ambulatoria/métodos , Análisis por Conglomerados , Femenino , Humanos , Fallo Renal Crónico/diagnóstico , Masculino , Tasa de Supervivencia , Factores de Tiempo , Estados Unidos
3.
Lancet Diabetes Endocrinol ; 6(11): 879-890, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30366567

RESUMEN

BACKGROUND: The Physical Function Trial (PFT) was one of seven Testosterone Trials (TTrials), the aim of which was to assess the effect of testosterone on mobility, self-reported physical function, falls, and patient global impression-of-change (PGIC) in older men with low testosterone concentrations, self-reported mobility limitation, and walking speed of less than 1·2 m/s. Using data from the PFT and the overall TTrials study population, we also aimed to identify whether the effect of testosterone on mobility differed according to baseline walking speed, mobility limitation, or other participant-level factors. METHODS: The TTrials included 790 men aged 65 years or older and with an average of two total testosterone concentrations below 275 ng/dL (9·5 nmol/L), of whom 390 had mobility limitation and a walking speed below 1·2 m/s and were enrolled in the PFT. Participants were assigned (by minimisation method) to 1% testosterone gel or placebo gel daily for 12 months, with participants and study staff masked to intervention allocation. The primary outcome of the PFT was an increase in 6 min walk test (6MWT) distance of 50 m or more. Here we report data for absolute change in 6MWT distance and physical component of Short Form-36 (PF10), and for PGIC and falls. Data are reported for men enrolled in the PFT and those who were not, and for all men in TTrials; data are also reported according to baseline walking speed and mobility limitation. Analyses were done in a modified intention-to-treat population in all patients who were allocated to treatment, had a baseline assessment, and at least one post-intervention assessment. The TTrials are registered with ClinicalTrials.gov, number NCT00799617. FINDINGS: The TTrials took place between April 28, 2011 and June 16, 2014. Of 790 TTrials participants, 395 were allocated to testosterone and 395 to placebo; of the 390 participants enrolled in the PFT, 193 were allocated to testosterone and 197 to placebo. As reported previously, 6MWT distance improved significantly more in the testosterone than in the placebo group among all men in the TTrials, but not in those who were enrolled in the PFT; among TTrials participants not enrolled in the PFT, 6MWT distance improved with a treatment effect of 8·9 m (95% CI 2·2-15·6; p=0·010). As reported previously, PF10 improved more in the testosterone group than in the placebo group in all men in TTrials and in men enrolled in the PFT; among those not enrolled in the PFT, PF10 improved with an effect size of 4·0 (1·5-6·5; p=0·0019). Testosterone-treated men with baseline walking speed of 1·2 m/s or higher had significantly greater improvements in 6MWT distance (treatment effect 14·2 m, 6·5-21·9; p=0·0004) and PF10 (4·9, 2·2-7·7; p=0·0005) than placebo-treated men. Testosterone-treated men reporting mobility limitation showed significantly more improvement in 6MWT distance (7·6 m, 1·0-14·1; p=0·0237) and PF10 (3·6, 1·3-5·9; p=0·0018) than placebo-treated men. Men in the testosterone group were more likely to perceive improvement in their walking ability (PGIC) than men in the placebo group, both for men enrolled in the PFT (effect size 2·21, 1·35-3·63; p=0·0018) and those not enrolled in the PFT (3·01, 1·61-5·63; p=0·0006). Changes in 6MWT distance were significantly associated with changes in testosterone, free testosterone, dihydrotestosterone, and haemoglobin concentrations. Fall frequency during the intervention period was identical in the two treatment groups of the TTrials (103 [27%] of 380 analysed in both groups had at least one fall). INTERPRETATION: Testosterone therapy consistently improved self-reported walking ability, modestly improved 6MWT distance (across all TTtrials participants), but did not affect falls. The effect of testosterone on mobility measures were related to baseline gait speed and self-reported mobility limitation, and changes in testosterone and haemoglobin concentrations. FUNDING: US National Institute on Aging and AbbVie.


Asunto(s)
Terapia de Reemplazo de Hormonas , Limitación de la Movilidad , Testosterona/uso terapéutico , Caminata , Accidentes por Caídas/prevención & control , Anciano , Ensayos Clínicos como Asunto , Humanos , Masculino , Testosterona/deficiencia , Resultado del Tratamiento , Prueba de Paso
4.
Endocr Rev ; 39(3): 369-386, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29522088

RESUMEN

The Testosterone Trials (TTrials) were a coordinated set of seven placebo-controlled, double-blind trials in 788 men with a mean age of 72 years to determine the efficacy of increasing the testosterone levels of older men with low testosterone. Testosterone treatment increased the median testosterone level from unequivocally low at baseline to midnormal for young men after 3 months and maintained that level until month 12. In the Sexual Function Trial, testosterone increased sexual activity, sexual desire, and erectile function. In the Physical Function Trial, testosterone did not increase the distance walked in 6 minutes in men whose walk speed was slow; however, in all TTrial participants, testosterone did increase the distance walked. In the Vitality Trial, testosterone did not increase energy but slightly improved mood and depressive symptoms. In the Cognitive Function Trial, testosterone did not improve cognitive function. In the Anemia Trial, testosterone increased hemoglobin in both men who had anemia of a known cause and in men with unexplained anemia. In the Bone Trial, testosterone increased volumetric bone mineral density and the estimated strength of the spine and hip. In the Cardiovascular Trial, testosterone increased the coronary artery noncalcified plaque volume as assessed using computed tomographic angiography. Although testosterone was not associated with more cardiovascular or prostate adverse events than placebo, a trial of a much larger number of men for a much longer period would be necessary to determine whether testosterone increases cardiovascular or prostate risk.


Asunto(s)
Envejecimiento , Andrógenos/farmacología , Ensayos Clínicos Controlados como Asunto , Terapia de Reemplazo de Hormonas , Evaluación de Resultado en la Atención de Salud , Testosterona/farmacología , Anciano , Envejecimiento/sangre , Andrógenos/administración & dosificación , Andrógenos/efectos adversos , Humanos , Masculino , Testosterona/administración & dosificación , Testosterona/efectos adversos , Testosterona/sangre
5.
J Clin Endocrinol Metab ; 103(2): 681-688, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29253154

RESUMEN

Context: Studies of the possible cardiovascular risk of testosterone treatment are inconclusive. Objective: To determine the effect of testosterone treatment on cardiovascular biomarkers in older men with low testosterone. Design: Double-blind, placebo-controlled trial. Setting: Twelve academic medical centers in the United States. Participants: In all, 788 men ≥65 years old with an average of two serum testosterone levels <275 ng/dL who were enrolled in The Testosterone Trials. Intervention: Testosterone gel, the dose adjusted to maintain the testosterone level in the normal range for young men, or placebo gel for 12 months. Main Outcome Measures: Serum markers of cardiovascular risk, including lipids and markers of glucose metabolism, fibrinolysis, inflammation, and myocardial damage. Results: Compared with placebo, testosterone treatment significantly decreased total cholesterol (adjusted mean difference, -6.1 mg/dL; P < 0.001), high-density lipoprotein cholesterol (adjusted mean difference, -2.0 mg/dL; P < 0.001), and low-density lipoprotein cholesterol (adjusted mean difference, -2.3 mg/dL; P = 0.051) from baseline to month 12. Testosterone also slightly but significantly decreased fasting insulin (adjusted mean difference, -1.7 µIU/mL; P = 0.02) and homeostatic model assessment‒insulin resistance (adjusted mean difference, -0.6; P = 0.03). Testosterone did not change triglycerides, d-dimer, C-reactive protein, interleukin 6, troponin, glucose, or hemoglobin A1c levels more than placebo. Conclusions and Relevance: Testosterone treatment of 1 year in older men with low testosterone was associated with small reductions in cholesterol and insulin but not with other glucose markers, markers of inflammation or fibrinolysis, or troponin. The clinical importance of these findings is unclear and requires a larger trial of clinical outcomes.


Asunto(s)
Biomarcadores/sangre , Sistema Cardiovascular/efectos de los fármacos , Sistema Cardiovascular/metabolismo , Testosterona/farmacología , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Envejecimiento/efectos de los fármacos , Sistema Cardiovascular/fisiopatología , Método Doble Ciego , Terapia de Reemplazo de Hormonas , Humanos , Hipogonadismo/sangre , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/fisiopatología , Masculino , Testosterona/sangre , Estados Unidos
6.
JAMA Intern Med ; 177(4): 471-479, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28241231

RESUMEN

Importance: As men age, they experience decreased serum testosterone concentrations, decreased bone mineral density (BMD), and increased risk of fracture. Objective: To determine whether testosterone treatment of older men with low testosterone increases volumetric BMD (vBMD) and estimated bone strength. Design, Setting, and Participants: Placebo-controlled, double-blind trial with treatment allocation by minimization at 9 US academic medical centers of men 65 years or older with 2 testosterone concentrations averaging less than 275 ng/L participating in the Testosterone Trials from December 2011 to June 2014. The analysis was a modified intent-to-treat comparison of treatment groups by multivariable linear regression adjusted for balancing factors as required by minimization. Interventions: Testosterone gel, adjusted to maintain the testosterone level within the normal range for young men, or placebo gel for 1 year. Main Outcomes and Measures: Spine and hip vBMD was determined by quantitative computed tomography at baseline and 12 months. Bone strength was estimated by finite element analysis of quantitative computed tomography data. Areal BMD was assessed by dual energy x-ray absorptiometry at baseline and 12 months. Results: There were 211 participants (mean [SD] age, 72.3 [5.9] years; 86% white; mean [SD] body mass index, 31.2 [3.4]). Testosterone treatment was associated with significantly greater increases than placebo in mean spine trabecular vBMD (7.5%; 95% CI, 4.8% to 10.3% vs 0.8%; 95% CI, -1.9% to 3.4%; treatment effect, 6.8%; 95% CI, 4.8%-8.7%; P < .001), spine peripheral vBMD, hip trabecular and peripheral vBMD, and mean estimated strength of spine trabecular bone (10.8%; 95% CI, 7.4% to 14.3% vs 2.4%; 95% CI, -1.0% to 5.7%; treatment effect, 8.5%; 95% CI, 6.0%-10.9%; P < .001), spine peripheral bone, and hip trabecular and peripheral bone. The estimated strength increases were greater in trabecular than peripheral bone and greater in the spine than hip. Testosterone treatment increased spine areal BMD but less than vBMD. Conclusions and Relevance: Testosterone treatment for 1 year of older men with low testosterone significantly increased vBMD and estimated bone strength, more in trabecular than peripheral bone and more in the spine than hip. A larger, longer trial could determine whether this treatment also reduces fracture risk. Trial Registration: clinicaltrials.gov Identifier: NCT00799617.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Fracturas de Cadera/prevención & control , Vértebras Lumbares , Fracturas de la Columna Vertebral/prevención & control , Testosterona , Absorciometría de Fotón/métodos , Anciano , Andrógenos/administración & dosificación , Andrógenos/sangre , Andrógenos/deficiencia , Método Doble Ciego , Vías de Administración de Medicamentos , Monitoreo de Drogas , Fracturas de Cadera/sangre , Fracturas de Cadera/diagnóstico , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/efectos de los fármacos , Masculino , Fracturas de la Columna Vertebral/sangre , Fracturas de la Columna Vertebral/diagnóstico , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/deficiencia , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
7.
JAMA Intern Med ; 177(4): 480-490, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28241237

RESUMEN

Importance: In one-third of older men with anemia, no recognized cause can be found. Objective: To determine if testosterone treatment of men 65 years or older with unequivocally low testosterone levels and unexplained anemia would increase their hemoglobin concentration. Design, Setting, and Participants: A double-blinded, placebo-controlled trial with treatment allocation by minimization using 788 men 65 years or older who have average testosterone levels of less than 275 ng/dL. Of 788 participants, 126 were anemic (hemoglobin ≤12.7 g/dL), 62 of whom had no known cause. The trial was conducted in 12 academic medical centers in the United States from June 2010 to June 2014. Interventions: Testosterone gel, the dose adjusted to maintain the testosterone levels normal for young men, or placebo gel for 12 months. Main Outcomes and Measures: The percent of men with unexplained anemia whose hemoglobin levels increased by 1.0 g/dL or more in response to testosterone compared with placebo. The statistical analysis was intent-to-treat by a logistic mixed effects model adjusted for balancing factors. Results: The men had a mean age of 74.8 years and body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) of 30.7; 84.9% were white. Testosterone treatment resulted in a greater percentage of men with unexplained anemia whose month 12 hemoglobin levels had increased by 1.0 g/dL or more over baseline (54%) than did placebo (15%) (adjusted OR, 31.5; 95% CI, 3.7-277.8; P = .002) and a greater percentage of men who at month 12 were no longer anemic (58.3%) compared with placebo (22.2%) (adjusted OR, 17.0; 95% CI, 2.8-104.0; P = .002). Testosterone treatment also resulted in a greater percentage of men with anemia of known cause whose month 12 hemoglobin levels had increased by 1.0 g/dL or more (52%) than did placebo (19%) (adjusted OR, 8.2; 95% CI, 2.1-31.9; P = .003). Testosterone treatment resulted in a hemoglobin concentration of more than 17.5 g/dL in 6 men who had not been anemic at baseline. Conclusions and Relevance: Among older men with low testosterone levels, testosterone treatment significantly increased the hemoglobin levels of those with unexplained anemia as well as those with anemia from known causes. These increases may be of clinical value, as suggested by the magnitude of the changes and the correction of anemia in most men, but the overall health benefits remain to be established. Measurement of testosterone levels might be considered in men 65 years or older who have unexplained anemia and symptoms of low testosterone levels. Trial Registration: clinicaltrials.gov Identifier: NCT00799617.


Asunto(s)
Anemia , Hemoglobinas/análisis , Testosterona , Anciano , Andrógenos/administración & dosificación , Andrógenos/sangre , Andrógenos/deficiencia , Anemia/sangre , Anemia/diagnóstico , Anemia/tratamiento farmacológico , Método Doble Ciego , Vías de Administración de Medicamentos , Monitoreo de Drogas/métodos , Terapia de Reemplazo de Hormonas/métodos , Humanos , Masculino , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/deficiencia , Resultado del Tratamiento
8.
JAMA ; 317(7): 708-716, 2017 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-28241355

RESUMEN

Importance: Recent studies have yielded conflicting results as to whether testosterone treatment increases cardiovascular risk. Objective: To test the hypothesis that testosterone treatment of older men with low testosterone slows progression of noncalcified coronary artery plaque volume. Design, Setting, and Participants: Double-blinded, placebo-controlled trial at 9 academic medical centers in the United States. The participants were 170 of 788 men aged 65 years or older with an average of 2 serum testosterone levels lower than 275 ng/dL (82 men assigned to placebo, 88 to testosterone) and symptoms suggestive of hypogonadism who were enrolled in the Testosterone Trials between June 24, 2010, and June 9, 2014. Intervention: Testosterone gel, with the dose adjusted to maintain the testosterone level in the normal range for young men, or placebo gel for 12 months. Main Outcomes and Measures: The primary outcome was noncalcified coronary artery plaque volume, as determined by coronary computed tomographic angiography. Secondary outcomes included total coronary artery plaque volume and coronary artery calcium score (range of 0 to >400 Agatston units, with higher values indicating more severe atherosclerosis). Results: Of 170 men who were enrolled, 138 (73 receiving testosterone treatment and 65 receiving placebo) completed the study and were available for the primary analysis. Among the 138 men, the mean (SD) age was 71.2 (5.7) years, and 81% were white. At baseline, 70 men (50.7%) had a coronary artery calcification score higher than 300 Agatston units, reflecting severe atherosclerosis. For the primary outcome, testosterone treatment compared with placebo was associated with a significantly greater increase in noncalcified plaque volume from baseline to 12 months (from median values of 204 mm3 to 232 mm3 vs 317 mm3 to 325 mm3, respectively; estimated difference, 41 mm3; 95% CI, 14 to 67 mm3; P = .003). For the secondary outcomes, the median total plaque volume increased from baseline to 12 months from 272 mm3 to 318 mm3 in the testosterone group vs from 499 mm3 to 541 mm3 in the placebo group (estimated difference, 47 mm3; 95% CI, 13 to 80 mm3; P = .006), and the median coronary artery calcification score changed from 255 to 244 Agatston units in the testosterone group vs 494 to 503 Agatston units in the placebo group (estimated difference, -27 Agatston units; 95% CI, -80 to 26 Agatston units). No major adverse cardiovascular events occurred in either group. Conclusions and Relevance: Among older men with symptomatic hypogonadism, treatment with testosterone gel for 1 year compared with placebo was associated with a significantly greater increase in coronary artery noncalcified plaque volume, as measured by coronary computed tomographic angiography. Larger studies are needed to understand the clinical implications of this finding. Trial Registration: clinicaltrials.gov Identifier: NCT00799617.


Asunto(s)
Andrógenos/efectos adversos , Enfermedad de la Arteria Coronaria/inducido químicamente , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Terapia de Reemplazo de Hormonas/efectos adversos , Testosterona/efectos adversos , Calcificación Vascular/diagnóstico por imagen , Anciano , Andrógenos/administración & dosificación , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/sangre , Progresión de la Enfermedad , Método Doble Ciego , Geles , Humanos , Hipogonadismo/sangre , Hipogonadismo/tratamiento farmacológico , Masculino , Variaciones Dependientes del Observador , Tamaño de la Muestra , Testosterona/administración & dosificación , Testosterona/sangre , Estados Unidos
9.
JAMA ; 317(7): 717-727, 2017 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-28241356

RESUMEN

Importance: Most cognitive functions decline with age. Prior studies suggest that testosterone treatment may improve these functions. Objective: To determine if testosterone treatment compared with placebo is associated with improved verbal memory and other cognitive functions in older men with low testosterone and age-associated memory impairment (AAMI). Design, Setting, and Participants: The Testosterone Trials (TTrials) were 7 trials to assess the efficacy of testosterone treatment in older men with low testosterone levels. The Cognitive Function Trial evaluated cognitive function in all TTrials participants. In 12 US academic medical centers, 788 men who were 65 years or older with a serum testosterone level less than 275 ng/mL and impaired sexual function, physical function, or vitality were allocated to testosterone treatment (n = 394) or placebo (n = 394). A subgroup of 493 men met criteria for AAMI based on baseline subjective memory complaints and objective memory performance. Enrollment in the TTrials began June 24, 2010; the final participant completed treatment and assessment in June 2014. Interventions: Testosterone gel (adjusted to maintain the testosterone level within the normal range for young men) or placebo gel for 1 year. Main Outcomes and Measures: The primary outcome was the mean change from baseline to 6 months and 12 months for delayed paragraph recall (score range, 0 to 50) among men with AAMI. Secondary outcomes were mean changes in visual memory (Benton Visual Retention Test; score range, 0 to -26), executive function (Trail-Making Test B minus A; range, -290 to 290), and spatial ability (Card Rotation Test; score range, -80 to 80) among men with AAMI. Tests were administered at baseline, 6 months, and 12 months. Results: Among the 493 men with AAMI (mean age, 72.3 years [SD, 5.8]; mean baseline testosterone, 234 ng/dL [SD, 65.1]), 247 were assigned to receive testosterone and 246 to receive placebo. Of these groups, 247 men in the testosterone group and 245 men in the placebo completed the memory study. There was no significant mean change from baseline to 6 and 12 months in delayed paragraph recall score among men with AAMI in the testosterone and placebo groups (adjusted estimated difference, -0.07 [95% CI, -0.92 to 0.79]; P = .88). Mean scores for delayed paragraph recall were 14.0 at baseline, 16.0 at 6 months, and 16.2 at 12 months in the testosterone group and 14.4 at baseline, 16.0 at 6 months, and 16.5 at 12 months in the placebo group. Testosterone was also not associated with significant differences in visual memory (-0.28 [95% CI, -0.76 to 0.19]; P = .24), executive function (-5.51 [95% CI, -12.91 to 1.88]; P = .14), or spatial ability (-0.12 [95% CI, -1.89 to 1.65]; P = .89). Conclusions and Relevance: Among older men with low testosterone and age-associated memory impairment, treatment with testosterone for 1 year compared with placebo was not associated with improved memory or other cognitive functions. Trial Registration: clinicaltrials.gov Identifier: NCT00799617.


Asunto(s)
Andrógenos/uso terapéutico , Trastornos de la Memoria/tratamiento farmacológico , Testosterona/uso terapéutico , Anciano , Cognición/efectos de los fármacos , Cognición/fisiología , Método Doble Ciego , Función Ejecutiva/efectos de los fármacos , Función Ejecutiva/fisiología , Geles , Humanos , Análisis de Intención de Tratar , Masculino , Memoria/efectos de los fármacos , Memoria/fisiología , Trastornos de la Memoria/sangre , Trastornos de la Memoria/etiología , Recuerdo Mental/efectos de los fármacos , Recuerdo Mental/fisiología , Valores de Referencia , Testosterona/sangre , Factores de Tiempo , Resultado del Tratamiento
10.
J Clin Endocrinol Metab ; 101(8): 3096-104, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27355400

RESUMEN

CONTEXT: The Testosterone Trials are a coordinated set of seven trials to determine the efficacy of T in symptomatic men ≥65 years old with unequivocally low T levels. Initial results of the Sexual Function Trial showed that T improved sexual activity, sexual desire, and erectile function. OBJECTIVE: To assess the responsiveness of specific sexual activities to T treatment; to relate hormone changes to changes in sexual function; and to determine predictive baseline characteristics and T threshold for sexual outcomes. DESIGN: A placebo-controlled trial. SETTING: Twelve academic medical centers in the United States. PARTICIPANTS: A total of 470 men ≥65 years of age with low libido, average T <275 ng/dL, and a partner willing to have sexual intercourse at least twice a month. METHODS: Men were assigned to take T gel or placebo for 1 year. Sexual function was assessed by three questionnaires every 3 months: the Psychosexual Daily Questionnaire, the Derogatis Interview for Sexual Function, and the International Index of Erectile Function. RESULTS: Compared with placebo, T administration significantly improved 10 of 12 measures of sexual activity. Incremental increases in total and free T and estradiol levels were associated with improvements in sexual activity and desire, but not erectile function. No threshold T level was observed for any outcome, and none of the 27 baseline characteristics predicted responsiveness to T. CONCLUSIONS: In older men with low libido and low T levels, improvements in sexual desire and activity in response to T treatment were related to the magnitude of increases in T and estradiol levels, but there was no clear evidence of a threshold effect.


Asunto(s)
Conducta Sexual/efectos de los fármacos , Disfunciones Sexuales Fisiológicas/tratamiento farmacológico , Testosterona/uso terapéutico , Anciano , Disfunción Eréctil/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Humanos , Libido/efectos de los fármacos , Masculino , Placebos , Disfunciones Sexuales Fisiológicas/sangre , Disfunciones Sexuales Fisiológicas/fisiopatología , Encuestas y Cuestionarios , Testosterona/sangre , Resultado del Tratamiento
11.
N Engl J Med ; 374(7): 611-24, 2016 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-26886521

RESUMEN

BACKGROUND: Serum testosterone concentrations decrease as men age, but benefits of raising testosterone levels in older men have not been established. METHODS: We assigned 790 men 65 years of age or older with a serum testosterone concentration of less than 275 ng per deciliter and symptoms suggesting hypoandrogenism to receive either testosterone gel or placebo gel for 1 year. Each man participated in one or more of three trials--the Sexual Function Trial, the Physical Function Trial, and the Vitality Trial. The primary outcome of each of the individual trials was also evaluated in all participants. RESULTS: Testosterone treatment increased serum testosterone levels to the mid-normal range for men 19 to 40 years of age. The increase in testosterone levels was associated with significantly increased sexual activity, as assessed by the Psychosexual Daily Questionnaire (P<0.001), as well as significantly increased sexual desire and erectile function. The percentage of men who had an increase of at least 50 m in the 6-minute walking distance did not differ significantly between the two study groups in the Physical Function Trial but did differ significantly when men in all three trials were included (20.5% of men who received testosterone vs. 12.6% of men who received placebo, P=0.003). Testosterone had no significant benefit with respect to vitality, as assessed by the Functional Assessment of Chronic Illness Therapy-Fatigue scale, but men who received testosterone reported slightly better mood and lower severity of depressive symptoms than those who received placebo. The rates of adverse events were similar in the two groups. CONCLUSIONS: In symptomatic men 65 years of age or older, raising testosterone concentrations for 1 year from moderately low to the mid-normal range for men 19 to 40 years of age had a moderate benefit with respect to sexual function and some benefit with respect to mood and depressive symptoms but no benefit with respect to vitality or walking distance. The number of participants was too few to draw conclusions about the risks of testosterone treatment. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT00799617.).


Asunto(s)
Fatiga/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Conducta Sexual/efectos de los fármacos , Testosterona/uso terapéutico , Caminata/fisiología , Anciano , Depresión/tratamiento farmacológico , Método Doble Ciego , Humanos , Libido/efectos de los fármacos , Masculino , Antígeno Prostático Específico/sangre , Valores de Referencia , Conducta Sexual/fisiología , Testosterona/efectos adversos , Testosterona/sangre
12.
Qual Life Res ; 25(4): 811-21, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26358063

RESUMEN

PURPOSE: Patient-reported outcome (PRO) measures are essential for assessing subjective patient experiences. Interactive voice response (IVR) data collection provides advantages for clinical trial design by standardizing and centralizing the assessment. Prior to adoption of IVR as a mode of PRO administration in the Testosterone Trials (TTrials), we compared IVR to paper versions of the instruments to be used. METHODS: IVR versions of the FACIT-Fatigue scale and Psychosexual Daily Questionnaire, Question 4, were developed. In one pilot study, IVR versions of these scales were compared to paper versions in 25 men ≥ 65 years at each of two clinical sites. In another study, IVR versions of the SF-36 Vitality Scale (SF-36), Positive and Negative Affect Scale, and Patient Health Questionnaire were evaluated in comparison with previously validated paper versions in 25 men at two clinical sites. Both paper and IVR versions of each instrument were administered in counterbalanced order, and test-retest reliability was evaluated by repeated administration of the test. Bland-Altman plots were used to assess the degree of agreement. Test-retest correlations for each measure were also determined. RESULTS: Satisfactory agreement was observed between IVR and paper versions of each study measure. Specifically, linear and highly positive associations were observed consistently across the study for IVR and paper versions of all study measures. These ranged from r = 0.91-0.99. Test-retest reliability for all measures was acceptable or better (r = 0.70-0.90). CONCLUSIONS: The IVR versions of TTrials endpoints in these two studies performed consistently well in comparison with paper versions.


Asunto(s)
Evaluación de la Discapacidad , Calidad de Vida , Disfunciones Sexuales Fisiológicas/diagnóstico , Software de Reconocimiento del Habla , Anciano , Anciano de 80 o más Años , Fatiga , Humanos , Masculino , Proyectos Piloto , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Voz
13.
BMC Pediatr ; 15: 37, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25886363

RESUMEN

BACKGROUND: With improved survival rates, short- and long-term respiratory complications of premature birth are increasing, adding significantly to financial and health burdens in the United States. In response, in May 2010, the National Institutes of Health (NIH) and the National Heart, Lung, and Blood Institute (NHLBI) funded a 5-year $18.5 million research initiative to ultimately improve strategies for managing the respiratory complications of preterm and low birth weight infants. Using a collaborative, multi-disciplinary structure, the resulting Prematurity and Respiratory Outcomes Program (PROP) seeks to understand factors that correlate with future risk for respiratory morbidity. METHODS/DESIGN: The PROP is an observational prospective cohort study performed by a consortium of six clinical centers (incorporating tertiary neonatal intensive care units [NICU] at 13 sites) and a data-coordinating center working in collaboration with the NHLBI. Each clinical center contributes subjects to the study, enrolling infants with gestational ages 23 0/7 to 28 6/7 weeks with an anticipated target of 750 survivors at 36 weeks post-menstrual age. In addition, each center brings specific areas of scientific focus to the Program. The primary study hypothesis is that in survivors of extreme prematurity specific biologic, physiologic and clinical data predicts respiratory morbidity between discharge and 1 year corrected age. Analytic statistical methodology includes model-based and non-model-based analyses, descriptive analyses and generalized linear mixed models. DISCUSSION: PROP incorporates aspects of NICU care to develop objective biomarkers and outcome measures of respiratory morbidity in the <29 week gestation population beyond just the NICU hospitalization, thereby leading to novel understanding of the nature and natural history of neonatal lung disease and of potential mechanistic and therapeutic targets in at-risk subjects. TRIAL REGISTRATION: Clinical Trials.gov NCT01435187.


Asunto(s)
Enfermedades del Prematuro/diagnóstico , Enfermedades Respiratorias/diagnóstico , Biomarcadores , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Cuidado Intensivo Neonatal , Examen Físico , Pronóstico , Estudios Prospectivos , Pruebas de Función Respiratoria
14.
J Gerontol A Biol Sci Med Sci ; 70(9): 1105-11, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25878029

RESUMEN

BACKGROUND: We describe the recruitment of men for The Testosterone (T) Trials, which were designed to determine the efficacy of T treatment. METHODS: Men were eligible if they were ≥65 years, had an average of two morning total T values <275 ng/dL with neither value >300 ng/mL, and had symptoms and objective evidence of mobility limitation, sexual dysfunction, and/or low vitality. Men had to be eligible for and enroll in at least one of these three main trials (physical function, sexual function, vitality). RESULTS: Men were recruited primarily through mass mailings in 12 U.S. communities: 82% of men who contacted the sites did so in response to mailings. Men who responded were screened by telephone to ascertain eligibility. Of 51,085 telephone screens, 53.5% were eligible for further screening. Of 23,889 initial screening visits (SV1), 2,781 (11.6%) men were eligible for the second screening visit (SV2), which 2,261 (81.3%) completed. At SV2, 931 (41.2%) men met the criteria for one or more trials, the T level criterion and had no other exclusions. Of these, 790 (84.6%) were randomized; 99 (12.5%) in all three trials and 348 (44%) in two trials. Their mean age was 72 years and mean body mass index (BMI) was 31.0 kg/m(2). Mean (standard deviation) total T (ng/dL) was 212.0 (40.0). CONCLUSION: Despite the telephone screening to enrollment ratio of 65 to 1, we met the recruitment goals for each trial. Recruitment of symptomatic older men with low testosterone levels is difficult but feasible.


Asunto(s)
Selección de Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Anciano , Humanos , Entrevistas como Asunto , Libido , Masculino , Limitación de la Movilidad , Estudios Multicéntricos como Asunto , Testosterona/sangre
15.
J Clin Endocrinol Metab ; 100(3): 1146-55, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25548978

RESUMEN

CONTEXT: The prevalence of sexual dysfunction, low vitality, and poor physical function increases with aging, as does the prevalence of low total and free testosterone (TT and FT) levels. However, the relationship between sex hormones and age-related alterations in older men is not clear. OBJECTIVE: To test the hypotheses that baseline serum TT, FT, estradiol (E2), and sex hormone-binding globulin (SHBG) levels are independently associated with sexual function, vitality, and physical function in older symptomatic men with low testosterone levels participating in the Testosterone Trials (TTrials). DESIGN: Cross-sectional study of baseline measures in the TTrials. SETTING: The study was conducted at 12 sites in the United States. PARTICIPANTS: The 788 TTrials participants were ≥ 65 years and had evidence of sexual dysfunction, diminished vitality, and/or mobility disability, and an average of two TT < 275 ng/dL. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Question 4 of Psychosocial Daily Questionnaire (PDQ-Q4), the FACIT-Fatigue Scale, and the 6-minute walk test. RESULTS: Baseline serum TT and FT, but not E2 or SHBG levels had small, but statistically significant associations with validated measures of sexual desire, erectile function, and sexual activity. None of these hormones was significantly associated within or across trials with FACIT-Fatigue, PHQ-9 Depression or Physical Function-10 scores, or gait speed. CONCLUSIONS: FT and TT levels were consistently, independently, and positively associated, albeit to a small degree, with measures of sexual desire, erectile function, and sexual activity, but not with measures of vitality or physical function in symptomatic older men with low T who qualified for the TTrials.


Asunto(s)
Hormonas Esteroides Gonadales/sangre , Hipopituitarismo/tratamiento farmacológico , Actividad Motora/fisiología , Conducta Sexual , Testosterona/deficiencia , Testosterona/uso terapéutico , Anciano , Anciano de 80 o más Años , Estudios Transversales , Disfunción Eréctil/tratamiento farmacológico , Disfunción Eréctil/epidemiología , Marcha/fisiología , Terapia de Reemplazo de Hormonas , Humanos , Hipopituitarismo/sangre , Hipopituitarismo/fisiopatología , Hipopituitarismo/psicología , Libido/fisiología , Masculino , Calidad de Vida/psicología , Encuestas y Cuestionarios , Estados Unidos/epidemiología
16.
Clin Trials ; 11(3): 362-375, 2014 06.
Artículo en Inglés | MEDLINE | ID: mdl-24686158

RESUMEN

Background The prevalence of low testosterone levels in men increases with age, as does the prevalence of decreased mobility, sexual function, self-perceived vitality, cognitive abilities, bone mineral density, and glucose tolerance, and of increased anemia and coronary artery disease. Similar changes occur in men who have low serum testosterone concentrations due to known pituitary or testicular disease, and testosterone treatment improves the abnormalities. Prior studies of the effect of testosterone treatment in elderly men, however, have produced equivocal results. Purpose To describe a coordinated set of clinical trials designed to avoid the pitfalls of prior studies and to determine definitively whether testosterone treatment of elderly men with low testosterone is efficacious in improving symptoms and objective measures of age-associated conditions. Methods We present the scientific and clinical rationale for the decisions made in the design of this set of trials. Results We designed The Testosterone Trials as a coordinated set of seven trials to determine if testosterone treatment of elderly men with low serum testosterone concentrations and symptoms and objective evidence of impaired mobility and/or diminished libido and/or reduced vitality would be efficacious in improving mobility (Physical Function Trial), sexual function (Sexual Function Trial), fatigue (Vitality Trial), cognitive function (Cognitive Function Trial), hemoglobin (Anemia Trial), bone density (Bone Trial), and coronary artery plaque volume (Cardiovascular Trial). The scientific advantages of this coordination were common eligibility criteria, common approaches to treatment and monitoring, and the ability to pool safety data. The logistical advantages were a single steering committee, data coordinating center and data and safety monitoring board, the same clinical trial sites, and the possibility of men participating in multiple trials. The major consideration in participant selection was setting the eligibility criterion for serum testosterone low enough to ensure that the men were unequivocally testosterone deficient, but not so low as to preclude sufficient enrollment or eventual generalizability of the results. The major considerations in choosing primary outcomes for each trial were identifying those of the highest clinical importance and identifying the minimum clinically important differences between treatment arms for sample size estimation. Potential limitations Setting the serum testosterone concentration sufficiently low to ensure that most men would be unequivocally testosterone deficient, as well as many other entry criteria, resulted in screening approximately 30 men in person to randomize one participant. Conclusion Designing The Testosterone Trials as a coordinated set of seven trials afforded many important scientific and logistical advantages but required an intensive recruitment and screening effort.


Asunto(s)
Ensayos Clínicos como Asunto , Terapia de Reemplazo de Hormonas/métodos , Proyectos de Investigación , Testosterona/uso terapéutico , Anciano , Humanos , Masculino , Testosterona/sangre
17.
Am Heart J ; 166(3): 435-41, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24016491

RESUMEN

BACKGROUND: Current dosing practices for warfarin are empiric and result in the need for frequent dose changes as the international normalized ratio gets too high or too low. As a result, patients are put at increased risk for thromboembolism, bleeding, and premature discontinuation of anticoagulation therapy. Prior research has identified clinical and genetic factors that can alter warfarin dose requirements, but few randomized clinical trials have examined the utility of using clinical and genetic information to improve anticoagulation control or clinical outcomes among a large, diverse group of patients initiating warfarin. METHODS: The COAG trial is a multicenter, double-blind, randomized trial comparing 2 approaches to guiding warfarin therapy initiation: initiation of warfarin therapy based on algorithms using clinical information plus an individual's genotype using genes known to influence warfarin response ("genotype-guided dosing") versus only clinical information ("clinical-guided dosing") (www.clinicaltrials.gov Identifier: NCT00839657). RESULTS: The COAG trial design is described. The study hypothesis is that, among 1,022 enrolled patients, genotype-guided dosing relative to clinical-guided dosing during the initial dosing period will increase the percentage of time that patients spend in the therapeutic international normalized ratio range in the first 4 weeks of therapy. CONCLUSION: The COAG will determine if genetic information provides added benefit above and beyond clinical information alone.


Asunto(s)
Anticoagulantes/administración & dosificación , Coagulación Sanguínea/genética , Hemorragia/inducido químicamente , Tromboembolia/etiología , Warfarina/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Genotipo , Humanos , Relación Normalizada Internacional , Resultado del Tratamiento , Estados Unidos
18.
J Am Med Inform Assoc ; 20(e2): e226-31, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23956018

RESUMEN

Widespread sharing of data from electronic health records and patient-reported outcomes can strengthen the national capacity for conducting cost-effective clinical trials and allow research to be embedded within routine care delivery. While pragmatic clinical trials (PCTs) have been performed for decades, they now can draw on rich sources of clinical and operational data that are continuously fed back to inform research and practice. The Health Care Systems Collaboratory program, initiated by the NIH Common Fund in 2012, engages healthcare systems as partners in discussing and promoting activities, tools, and strategies for supporting active participation in PCTs. The NIH Collaboratory consists of seven demonstration projects, and seven problem-specific working group 'Cores', aimed at leveraging the data captured in heterogeneous 'real-world' environments for research, thereby improving the efficiency, relevance, and generalizability of trials. Here, we introduce the Collaboratory, focusing on its Phenotype, Data Standards, and Data Quality Core, and present early observations from researchers implementing PCTs within large healthcare systems. We also identify gaps in knowledge and present an informatics research agenda that includes identifying methods for the definition and appropriate application of phenotypes in diverse healthcare settings, and methods for validating both the definition and execution of electronic health records based phenotypes.


Asunto(s)
Registros Electrónicos de Salud/normas , National Institutes of Health (U.S.) , Fenotipo , Ensayos Clínicos Pragmáticos como Asunto , Humanos , Estados Unidos
19.
Clin J Am Soc Nephrol ; 4(8): 1302-11, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19541818

RESUMEN

BACKGROUND AND OBJECTIVES: The Chronic Renal Insufficiency Cohort (CRIC) Study was established to examine risk factors for the progression of chronic kidney disease (CKD) and cardiovascular disease (CVD) in patients with CKD. We examined baseline demographic and clinical characteristics. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Seven clinical centers recruited adults who were aged 21 to 74 yr and had CKD using age-based estimated GFR (eGFR) inclusion criteria. At baseline, blood and urine specimens were collected and information regarding health behaviors, diet, quality of life, and functional status was obtained. GFR was measured using radiolabeled iothalamate in one third of participants. RESULTS: A total of 3612 participants were enrolled with mean age +/- SD of 58.2 +/- 11.0 yr; 46% were women, and 47% had diabetes. Overall, 45% were non-Hispanic white, 46% were non-Hispanic black, and 5% were Hispanic. Eighty-six percent reported hypertension, 22% coronary disease, and 10% heart failure. Mean body mass index was 32.1 +/- 7.9 kg/m(2), and 47% had a BP >130/80 mmHg. Mean eGFR was 43.4 +/- 13.5 ml/min per 1.73 m(2), and median (interquartile range) protein excretion was 0.17 g/24 h (0.07 to 0.81 g/24 h). Lower eGFR was associated with older age, lower socioeconomic and educational level, cigarette smoking, self-reported CVD, peripheral arterial disease, and elevated BP. CONCLUSIONS: Lower level of eGFR was associated with a greater burden of CVD as well as lower socioeconomic and educational status. Long-term follow-up of participants will provide critical insights into the epidemiology of CKD and its relationship to adverse outcomes.


Asunto(s)
Enfermedades Cardiovasculares/complicaciones , Tasa de Filtración Glomerular , Fallo Renal Crónico/etiología , Riñón/fisiopatología , Insuficiencia Renal Crónica/fisiopatología , Adulto , Factores de Edad , Anciano , Presión Sanguínea , Enfermedades Cardiovasculares/etnología , Enfermedades Cardiovasculares/fisiopatología , Progresión de la Enfermedad , Escolaridad , Femenino , Humanos , Fallo Renal Crónico/etnología , Fallo Renal Crónico/fisiopatología , Masculino , Persona de Mediana Edad , Selección de Paciente , Estudios Prospectivos , Proteinuria/etiología , Proteinuria/fisiopatología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/etnología , Medición de Riesgo , Factores de Riesgo , Fumar/efectos adversos , Clase Social , Estados Unidos/epidemiología , Adulto Joven
20.
J Am Soc Nephrol ; 14(7 Suppl 2): S148-53, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12819321

RESUMEN

Insights into end-stage renal disease have emerged from many investigations but less is known about the epidemiology of chronic renal insufficiency (CRI) and its relationship to cardiovascular disease (CVD). The Chronic Renal Insufficiency Cohort (CRIC) Study was established to examine risk factors for progression of CRI and CVD among CRI patients and develop models to identify high-risk subgroups, informing future treatment trials, and increasing application of preventive therapies. CRIC will enroll approximately 3000 individuals at seven sites and follow participants for up to 5 yr. CRIC will include a racially and ethnically diverse group of adults aged 21 to 74 yr with a broad spectrum of renal disease severity, half of whom have diagnosed diabetes mellitus. CRIC will exclude subjects with polycystic kidney disease and those on active immunosuppression for glomerulonephritis. Subjects will undergo extensive clinical evaluation at baseline and at annual clinic visits and via telephone at 6 mo intervals. Data on quality of life, dietary assessment, physical activity, health behaviors, depression, cognitive function, health care resource utilization, as well as blood and urine specimens will be collected annually. (125)I-iothalamate clearances and CVD evaluations including a 12-lead surface electrocardiogram, an echocardiogram, and coronary electron beam or spiral CT will be performed serially. Analyses planned in CRIC will provide important information on potential risk factors for progressive CRI and CVD. Insights from CRIC should lead to the formulation of hypotheses regarding therapy that will serve as the basis for targeted interventional trials focused on reducing the burden of CRI and CVD.


Asunto(s)
Fallo Renal Crónico/epidemiología , Adulto , Distribución por Edad , Anciano , Femenino , Humanos , Incidencia , Fallo Renal Crónico/terapia , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Selección de Paciente , Pronóstico , Diálisis Renal/estadística & datos numéricos , Proyectos de Investigación , Medición de Riesgo , Índice de Severidad de la Enfermedad , Distribución por Sexo , Tasa de Supervivencia , Estados Unidos/epidemiología
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