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1.
Contraception ; 91(2): 127-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25604900

RESUMO

OBJECTIVES: Combined oral contraceptives (COCs) decrease testosterone (T) levels. This study investigated restoration of T and other androgen concentrations during COC use by 'co-administration' of dehydroepiandrosterone (DHEA). STUDY DESIGN: In this randomized, double-blind, placebo-controlled study in 99 new COC starters (18-35 years old with body mass index range 18-34 kg/m²), a COC containing 30mcg ethinylestradiol (EE) and 3 mg drospirenone (DRSP) was used for 3cycles, followed by 6cycles of the same COC combined with either 50 mg/day DHEA or placebo. Total T, albumin, sex hormone-binding globulin (SHBG), DHEA-sulfate (DHEA-S), Δ4-androstenedione (AD), 3α-androstanediol glucuronide (ADG) and estradiol (E2) were measured, whereas free T and the free T index (FTI) were calculated. Assessments took place at baseline (no COC use), after the run-in period (COC use alone) and during the treatment period (DHEA or placebo). RESULTS: During COC use alone, androgen levels decreased, especially total T by 62% and free T by 86%, and SHBG increased by 243%. Total T increased with DHEA compared to placebo (change from end of run-in period to end of treatment period -- 1.3±1.2 nmol/L vs. 0.0±0.4 nmol/L; p<.0001) -- and was restored to baseline levels. Free T and the FTI increased significantly (p<.0001), but the free T level was still 53% below baseline levels. DHEA-S, AD and ADG increased significantly to levels above baseline (p<.0001 for each). DHEA had no effect on SHBG, albumin and E2. CONCLUSIONS: An EE/DRSP containing COC strongly suppressed endogenous androgen concentrations in all users. The addition of 50 mg DHEA to a COC regimen containing EE/DRSP restored total T to baseline levels, but free T levels were restored by only 47% as most of the T remains bound to SHBG. IMPLICATIONS: When using a COC that increases SHBG considerably, a daily dose of 50 mg DHEA is insufficient to normalize free T levels completely.


Assuntos
Androstenos/efeitos adversos , Anticoncepcionais Orais Combinados/efeitos adversos , Desidroepiandrosterona/uso terapêutico , Etinilestradiol/efeitos adversos , Hipogonadismo/prevenção & controle , Globulina de Ligação a Hormônio Sexual/agonistas , Testosterona/sangue , Regulação para Cima/efeitos dos fármacos , Adolescente , Adulto , Antagonistas de Androgênios/efeitos adversos , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/sangue , Androstenodiona/sangue , Bélgica , Sulfato de Desidroepiandrosterona/sangue , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Hipogonadismo/sangue , Hipogonadismo/induzido quimicamente , Globulina de Ligação a Hormônio Sexual/análise , Solubilidade , Testosterona/agonistas , Testosterona/antagonistas & inibidores , Testosterona/química , Adulto Jovem
2.
Hum Reprod Update ; 20(1): 76-105, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24082040

RESUMO

UNLABELLED: BACKGROUND; Combined oral contraceptives (COCs) reduce levels of androgen, especially testosterone (T), by inhibiting ovarian and adrenal androgen synthesis and by increasing levels of sex hormone-binding globulin (SHBG). Although this suppressive effect has been investigated by numerous studies over many years, to our knowledge no systematic review concerning this issue had been performed. This systematic review and meta-analysis was performed to evaluate the effect of COCs on concentrations of total T, free T and SHBG in healthy women and to evaluate differences between the various types of COCs (e.g. estrogen dose, type of progestin) and the assays used to assess total T and free T. METHODS: A review of the literature was performed using database searches (MEDLINE, EMBASE and the Cochrane Central Register of Clinical Trials) and all publications (from inception date until July 2012) investigating the effect of COCs on androgen levels in healthy women were considered eligible for selection. Three reviewers were involved in study selection, data extraction and critical appraisal. For the meta-analysis, data on total T, free T and SHBG were extracted and combined using random effects analysis. Additional subgroup analyses were performed to evaluate differences between the various types of COCs (e.g. estrogen dose, type of progestin) and the assays used to assess total T or free T. RESULTS: A total of 151 records were identified by systematic review and 42 studies with a total of 1495 healthy young women (age range: 18-40 years) were included in the meta-analysis. All included studies were experimental studies and 21 were non-comparative. Pooling of the results derived from all the included papers showed that total T levels significantly decreased during COC use [mean difference (MD) (95% confidence interval, CI) -0.49 nmol/l (-0.55, -0.42); P < 0.001]. Significantly lower levels of free T were also found [relative change (95% CI) 0.39 (0.35, 0.43); P < 0.001], with a mean decrease of 61%. On the contrary, SHBG concentrations significantly increased during all types of COC use [MD (95% CI) 99.08 nmol/l (86.43, 111.73); P < 0.001]. Subgroup analyses revealed that COCs containing 20-25 µg EE had similar effects on total and free T compared with COCs with 30-35 µg EE. In addition, suppressive effects on T levels were not different when comparing different types of progestins. However, subgroup analyses for the estrogen dose and the progestin type in relation to changes in SHBG levels did show significant differences: COCs containing second generation progestins and/or the lower estrogen doses (20-25 µg EE) were found to have less impact on SHBG concentrations. CONCLUSIONS: The current literature review and meta-analysis demonstrates that COCs decrease circulating levels of total T and free T and increase SBHG concentrations. Due to the SHBG increase, free T levels decrease twice as much as total T. The estrogen dose and progestin type of the COC do not influence the decline of total and free T, but both affect SHBG. The clinical implications of suppressed androgen levels during COC use remain to be elucidated.


Assuntos
Anticoncepcionais Orais Combinados/uso terapêutico , Estrogênios/uso terapêutico , Progestinas/uso terapêutico , Testosterona/sangue , Adulto , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Globulina de Ligação a Hormônio Sexual , Adulto Jovem
3.
Ann Neurol ; 20(1): 89-91, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3017187

RESUMO

Three siblings with chemically proved cerebrotendinous xanthomatosis presented with typical neurological manifestations of dementia and spinocerebellar disorder. Electrodiagnostic tests revealed demyelinating neuropathy in all three. Sural nerve biopsies showed loss of myelinated large fibers, marked Schwann cell proliferation, and onion bulb formation. Teased-fiber preparations confirmed the occurrence of segmental demyelination and remyelination. We suggest that demyelinating neuropathy is part of the neurological spectrum of cerebrotendinous xanthomatosis and should be considered in the differential diagnosis of a recessively inherited motor and sensory neuropathy.


Assuntos
Encefalopatias/genética , Doenças Desmielinizantes/genética , Doenças do Sistema Nervoso Periférico/genética , Tendões , Xantomatose/genética , Adolescente , Adulto , Doenças Cerebelares/genética , Demência/genética , Feminino , Humanos , Masculino , Doenças Musculares/genética , Doenças da Medula Espinal/genética , Síndrome
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