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1.
BMC Pediatr ; 19(1): 131, 2019 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-31023296

RESUMEN

BACKGROUND: Adolescents with DMD treated with chronic high dose GC therapy typically have profound pubertal delay. Testosterone, the main circulating androgen in men, promotes virilisation and growth with associated accrual of fat-free muscle mass and bone mineral content. Testosterone therapy is routinely used to mimic the normal stages of pubertal development in patients with hypogonadotrophic hypogonadism, androgen deficiency secondary to testicular disease and in constitutional delay of growth and puberty (CDGP). Improved life expectancy in DMD has meant that more adolescents are eligible for testosterone supplementation but there is little objective data regarding the impact of this treatment on muscle structure and function, bone integrity and overall well-being. METHODS: This is a single centre observational clinical trial (NCT02571205) that aims to follow the progress of 15 adolescents with Duchenne muscular dystrophy and delayed puberty as they are managed with incremental testosterone therapy to induce puberty. Subjects will all be treated with a steadily increasing dose of testosterone administered by injection every 4 weeks and data will be collected to help us determine the effectiveness and tolerability of the described treatment regimen. We will use the data to explore the effects of testosterone on pubertal development, growth, muscle strength and function, bone mineral density, body composition with a detailed record of any adverse events. We will also carry out interviews to explore the boys' views on the tolerability of the regimen. The study will last for 27 months in total for each participant. DISCUSSION: Our experience has indicated that testosterone treatment in adolescents with DMD is liked and well tolerated but we have not collected objective data on a specific treatment regimen and there is no current consensus. Testosterone supplementation is not part of the standard of care of pubertal delay in DMD but inclusion in future protocols may be appropriate depending on the results of this trial. TRIAL REGISTRATION: EudraCT Number: 2015-003195-68. Research Registry & References: Clinical trials.gov- NCT02571205 (registered 8/10/15).


Asunto(s)
Glucocorticoides/efectos adversos , Fuerza Muscular/efectos de los fármacos , Distrofia Muscular de Duchenne/tratamiento farmacológico , Pubertad Tardía/tratamiento farmacológico , Testosterona/administración & dosificación , Adolescente , Composición Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Niño , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Estudios de Seguimiento , Glucocorticoides/administración & dosificación , Humanos , Inyecciones Intramusculares , Masculino , Distrofia Muscular de Duchenne/complicaciones , Distrofia Muscular de Duchenne/diagnóstico , Satisfacción del Paciente , Estudios Prospectivos , Resultado del Tratamiento , Reino Unido
2.
Farm Hosp ; 36(1): 3-10, 2012.
Artículo en Español | MEDLINE | ID: mdl-21514863

RESUMEN

OBJECTIVE: To estimate the budget impact of somatrophin (Genotonorm) use in growth hormone deficiency (GHD) patients during the transition between childhood and adulthood. METHOD: A budget impact model was designed under the Spanish National Health System with a 5-year time horizon. Calculations of susceptible patients were based on disease prevalence (0.02%) applied to Spanish population. From total GHD cases, 60% was considered persistent and treatment candidates. An expert panel assumed that 20% of candidates would reject the treatment and 8% would withdraw therapy annually. Considered costs included: therapy costs, diagnosis (test and medical visit) and follow-up cost. RESULTS: There would be 49, 93, 132, 186 and 199 patients undergoing treatment each year (2010-2014). The total impact of Genotonorm use during the transition phase would be €367,691, €655,430, €1044,874, €1334,059, and €1594,670 for years 1 to 5. The average annual cost per patient would be €7506, €7059, €7903, €7960, €7995. CONCLUSIONS: GHD treatment during the transition phase in Spain poses an annual average layout of €7684/patient.


Asunto(s)
Presupuestos , Hormona de Crecimiento Humana/economía , Adolescente , Algoritmos , Niño , Técnicas de Diagnóstico Endocrino/economía , Costos de los Medicamentos , Monitoreo de Drogas/economía , Utilización de Medicamentos , Costos de Hospital , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Modelos Teóricos , Programas Nacionales de Salud/economía , Pubertad Tardía/tratamiento farmacológico , Pubertad Tardía/economía , Pubertad Tardía/epidemiología , Proteínas Recombinantes/economía , Proteínas Recombinantes/uso terapéutico , España/epidemiología , Adulto Joven
3.
Ann N Y Acad Sci ; 1054: 462-6, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16339698

RESUMEN

The pervasiveness of low bone mass (LBM) in beta-thalassemia (Thal) patients (pts) is escalating as the average life expectancy of these pts increases. Adolescence is a period of substantial bone accrual, which is crucial for future bone strength. Studies of LBM are prevalent among adults with Thal. However, limited information exists about bone accrual and LBM in adolescents with the disease. Thirty-one pts with beta-Thal (26 Thal major [TM], 5 Thal intermedia [TI]), aged 9-20 years (mean: 15.3 years), 14 males and 17 females, underwent measurement of spinal bone mineral density (BMD) by DEXA (Lunar, Prodigy). Height, weight, body mass index, and Tanner stage were assessed at the time of the BMD measurement. A total of 16.1% of the patients had normal bone mass (Z > or = -1), 22.6% had reduced bone mass (Z = -1 to -2), and 61.3% had low bone mass (Z < or = -2). BMD Z correlated with height and weight Z scores. Some 53.9% of subjects had normal gonadal function and 46.1% had induced puberty with gonadal steroids. BMD Z significantly worsened with age (P < .0001). However, there was no difference in the LBM prevalence between subjects with normal versus those with induced puberty: BMD Z was -2 or less in 71.4% of subjects with normal puberty versus 66.7% in those with induced puberty. Our results indicate a high prevalence of LBM among adolescents with Thal regardless of adequate transfusion and chelation regimens. Bone accrual was found to be suboptimal in adolescents with normal or induced puberty. Thus, calcium and vitamin D supplementation with antiresorptive therapies should be evaluated in the adolescent Thal pt with close monitoring of growth and sexual development.


Asunto(s)
Densidad Ósea , Enfermedades Óseas Metabólicas/etiología , Osteoporosis/etiología , Talasemia beta/complicaciones , Adolescente , Adulto , Antropometría , Transfusión Sanguínea , Enfermedades Óseas Metabólicas/epidemiología , Terapia por Quelación , Niño , Terapia Combinada , Deferoxamina/uso terapéutico , Progresión de la Enfermedad , Enfermedades del Sistema Endocrino/tratamiento farmacológico , Enfermedades del Sistema Endocrino/epidemiología , Enfermedades del Sistema Endocrino/etiología , Femenino , Hormonas Esteroides Gonadales/uso terapéutico , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/epidemiología , Hipogonadismo/etiología , Quelantes del Hierro/uso terapéutico , Masculino , Osteoporosis/epidemiología , Prevalencia , Pubertad Tardía/tratamiento farmacológico , Pubertad Tardía/epidemiología , Pubertad Tardía/etiología , Columna Vertebral/química
4.
J Clin Endocrinol Metab ; 89(7): 3326-31, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15240610

RESUMEN

The increase in pituitary GH secretion that occurs during mid-late puberty in boys follows an increase in circulating testosterone (T) concentration; the direct mechanism by which this occurs is unknown. We hypothesized that T increases GH secretion during puberty by augmenting hypothalamic output of GHRH. Using constant infusions of a GHRH antagonist, we tested this hypothesis in six early pubertal boys with constitutional delay of growth and adolescence who had a mean chronological age of 14.0 +/- 0.3 yr and mean bone age of 11.4 +/- 0.2 yr. Blood samples were obtained from subjects every 15 min for 24 h during the overnight infusion of normal saline (2000-0600 h) and again during the overnight infusion of GHRH antagonist (0.33 microg/kg/h) the following night. Subjects then received transdermal T (5-mg patch) for 12 h nightly and were studied again after 4 wk of treatment. Serum samples were assayed for GH and total ghrelin; the percent suppression of GH during GHRH antagonist infusion was calculated. Morning serum T rose from 0.44 +/- 0.09 to 4.43 +/- 0.74 microg/liter (P = 0.005). T treatment was associated with a 92.6% increase in mean nocturnal GH secretion area under the curve (830 +/- 177 to 1599 +/- 340 microg/24 h.liter). Infusion of GHRH-antagonist suppressed mean nocturnal GH area under the curve by 29.1% before T treatment (830 +/- 177 to 621 +/- 168 microg/24 h.liter), and by 29.4% after T treatment (1599 +/- 340 to 1182 +/- 249 microg/24 h.liter; P = 0.99). Somatotroph sensitivity to GHRH was tested with 0.1- and 1.0-microg/kg doses of GHRH-44 iv; GH response did not change with regard to T treatment. The mean 24-h concentration of total ghrelin was unchanged with regard to T treatment. In summary, nightly transdermal T administration in six boys with constitutional delay of growth and adolescence increased GH output almost 2-fold, whereas the degree of GH suppressibility by GHRH antagonist remained unchanged. We conclude that the T-associated augmentation of GH secretion during early puberty in boys is unlikely to involve an absolute increase in hypothalamic GHRH output.


Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona Liberadora de Hormona del Crecimiento/metabolismo , Hormona de Crecimiento Humana/metabolismo , Hipotálamo/metabolismo , Pubertad Tardía/tratamiento farmacológico , Testosterona/uso terapéutico , Adolescente , Ritmo Circadiano , Ghrelina , Trastornos del Crecimiento/metabolismo , Hormona Liberadora de Hormona del Crecimiento/antagonistas & inhibidores , Hormona Liberadora de Hormona del Crecimiento/farmacología , Humanos , Masculino , Hormonas Peptídicas/sangre , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Pubertad Tardía/metabolismo , Testosterona/sangre
5.
Clin Endocrinol (Oxf) ; 60(6): 682-7, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15163330

RESUMEN

OBJECTIVE: To assess the effect of nutritional supplementation on growth and puberty in constitutionally delayed children. PATIENTS: One hundred and two boys, 13.6-15.5 years of age, who were referred because of short stature and delayed puberty. METHODS: The boys were randomly allocated to one of the following treatment groups: oxandrolone therapy, 5 mg/day for 6 months (n = 15), testosterone depot, 100 mg monthly for 3 months (n = 15) or for 6 months (n = 20), nutritional programme (n = 17), oxandrolone and nutritional programme (n = 15) or passive observation (n = 20). Boys in the nutritional programmes received 12 mg/day iron and 6000 IU/week of vitamin A. Outcome measurements were of height, weight, pubertal signs, dietary intake, serum vitamin A, iron, GH and IGF-1. RESULTS: Six months of vitamin A supplementation induced growth acceleration similar to that seen in the oxandrolone- and testosterone-treated children, and significantly greater than in the observation group (9.3 +/- 2.9 vs. 4.0 +/- 0.9 crn/yr, P < 0.001). Whereas in the vitamin A-supplemented group, puberty (increase in testicular volume >/= 12 ml) was induced within 12 months. In all testosterone-treated patients, pubic hair was noted within 3 months and a testicular volume of >/= 12 ml was observed 9-12 months after the initiation of therapy. No pubertal signs were noted in the observation group during this time. CONCLUSIONS: Subnormal vitamin A intake is one of the aetiological factors in delayed pubertal maturation. Supplementation of both vitamin A and iron to normal constitutionally delayed children with subnormal vitamin A intake is as efficacious as hormonal therapy in the induction of growth and puberty.


Asunto(s)
Andrógenos/uso terapéutico , Terapia de Reemplazo de Hormonas/métodos , Hierro/administración & dosificación , Pubertad Tardía/tratamiento farmacológico , Vitamina A/administración & dosificación , Adolescente , Análisis de Varianza , Preparaciones de Acción Retardada , Quimioterapia Combinada , Humanos , Modelos Lineales , Masculino , Oxandrolona/uso terapéutico , Testosterona/uso terapéutico
6.
J Clin Endocrinol Metab ; 82(10): 3414-20, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9329378

RESUMEN

Activation of the gonadotropic and somatotropic axes in puberty is marked by striking amplification of pulsatile neurohormone secretion. In addition, each axis, as a whole, constitutes a regulated network whose feedback relationships are likely to manifest important changes at the time of puberty. Here, we use the regularity statistic, approximate entropy (ApEn), to assess feedback activity within the somatotropic (hypothalamo-pituitary/GH-insulin-like growth factor I) axis indirectly. To this end, we studied pubertal boys and prepubertal girls or boys with sex-steroid hormone deficiency treated short-term with estrogen, testosterone, or a nonaromatizable androgen in a total of 3 paradigms. First, our cross-sectional analysis of 53 boys at various stages of puberty or young adulthood revealed that mean ApEn, taken as a measure of feedback complexity, of 24-h serum GH concentration profiles is maximal in pre- and mid-late puberty, followed by a significant decline in postpubertal adolescence and young adulthood (P = 0.0008 by ANOVA). This indicates that marked disorderliness of the GH release process occurs in mid-late puberty at or near the time of peak growth velocity, with a return to maximal orderliness thereafter at reproductive maturity. Second, oral administration of ethinyl estradiol for 5 weeks to 7 prepubertal girls with Turner's syndrome also augmented ApEn significantly (P = 0.018), thus showing that estrogen per se can induce greater irregularity of GH secretion. Third, in 5 boys with constitutionally delayed puberty, im testosterone administration also significantly increased ApEn of 24-h GH time series (P = 0.0045). In counterpoint, 5 alpha-dihydrotestosterone, a nonaromatizable androgen, failed to produce a significant ApEn increase (P > 0.43). We conclude from these three distinct experimental contexts that aromatization of testosterone to estrogen in boys, or estrogen itself in girls, is likely the proximate sex-steroid stimulus amplifying secretory activity of the GH axis in puberty. In addition, based on inferences derived from mathematical models that mechanistically link increased disorderliness (higher ApEn) to network changes, we suggest that sex-steroid hormones in normal puberty modulate feedback within, and hence network function of, the hypothalamo-pituitary/GH-insulin-like growth factor I axis.


Asunto(s)
Estrógenos/fisiología , Hormona de Crecimiento Humana/fisiología , Hipotálamo/fisiología , Factor I del Crecimiento Similar a la Insulina/fisiología , Pubertad Tardía/fisiopatología , Testosterona/fisiología , Adolescente , Adulto , Andrógenos/fisiología , Entropía , Retroalimentación , Femenino , Hormonas Esteroides Gonadales/uso terapéutico , Humanos , Masculino , Pubertad Tardía/tratamiento farmacológico , Síndrome de Turner/tratamiento farmacológico , Síndrome de Turner/fisiopatología
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