Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Endocr Rev ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795365

RESUMO

Glucocorticoid hormones (GC) are secreted in a circadian and ultradian rhythm and play a critical role in maintaining physiological homeostasis, with both excess and insufficient GC associated with adverse effects on health. Current assessment of GC status is primarily clinical, often in conjunction with serum cortisol values, which may be stimulated or suppressed depending on the GC disturbance being assessed. In the setting of extreme perturbations in cortisol levels i.e. markedly low or high levels, symptoms and signs of GC dysfunction may be overt. However, when disturbances in cortisol GC status values are less extreme, such as when assessing optimization of a GC replacement regimen, signs and symptoms can be more subtle or non-specific. Current tools for assessing GC status, are best suited to identifying profound disturbances but may lack sensitivity for confirming optimal GC status. Moreover, single cortisol values do not necessarily reflect an individual's GC status, as they are subject to inter- and intra-individual variation, do not take into account the pulsatile nature of cortisol secretion, variation in binding proteins, or local tissue concentrations as dictated by 11ßeta-hydroxysteroid dehydrogenase (11ß-HSD) activity, as well as GC receptor sensitivity. In the present review, we evaluate possible alternative methods for the assessment of GC status that do not solely rely on measurement of circulating cortisol levels. We discuss the potential of changes in metabolomic profiles, miRNA, gene expression, epigenetic, and other novel biomarkers such as GDF-15 and osteocalcin, that could in future aid in the objective classification of GC status.

2.
Andrology ; 12(3): 477-486, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38233215

RESUMO

BACKGROUND: Testosterone is safe and highly effective in men with organic hypogonadism, but worldwide testosterone prescribing has recently shifted towards middle-aged and older men, mostly with low testosterone related to age, diabetes and obesity, for whom there is less established evidence of clinical safety and benefit. The value of testosterone treatment in middle-aged and older men with low testosterone is yet to be determined. We therefore evaluated the cost-effectiveness of testosterone treatment in such men with low testosterone compared with no treatment. METHODS: A cost-utility analysis comparing testosterone with no treatment was conducted following best practices in decision modelling. A cohort Markov model incorporating relevant care pathways for individuals with hypogonadism was developed for a 10-year-time horizon. Clinical outcomes were obtained from an individual patient meta-analysis of placebo-controlled, double-blind randomised studies. Three starting age categories were defined: 40, 60 and 75 years. Cost utility (quality-adjusted life years) accrued and costs of testosterone treatment, monitoring and cardiovascular complications were compared to estimate incremental cost-effectiveness ratios and cost-effectiveness acceptability curves for selected scenarios. RESULTS: Ten-year excess treatment costs for testosterone compared with non-treatment ranged between £2306 and £3269 per patient. Quality-adjusted life years results depended on the instruments used to measure health utilities. Using Beck depression index-derived quality-adjusted life years data, testosterone was cost-effective (incremental cost-effectiveness ratio <£20,000) for men aged <75 years, regardless of morbidity and mortality sensitivity analyses. Testosterone was not cost-effective in men aged >75 years in models assuming increased morbidity and/or mortality. CONCLUSIONS AND FUTURE RESEARCH: Our data suggest that testosterone is cost-effective in men <75 years when Beck depression index-derived quality-adjusted life years data are considered; cost-effectiveness in men >75 years is dependent on cardiovascular safety. However, more robust and longer-term cost-utility data are needed to verify our conclusion.


Assuntos
Hipogonadismo , Testosterona , Masculino , Pessoa de Meia-Idade , Humanos , Idoso , Análise Custo-Benefício , Testosterona/efeitos adversos , Hipogonadismo/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Fertil Steril ; 121(2): 334-345, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37977226

RESUMO

OBJECTIVE: To quantify how representative a single measure of reproductive hormone level is of the daily hormonal profile using data from detailed hormonal sampling in the saline placebo-treated arm conducted over several hours. DESIGN: Retrospective analysis of data from previous interventional research studies evaluating reproductive hormones. SETTING: Clinical Research Facility at a tertiary reproductive endocrinology centre at Imperial College Hospital NHS Foundation Trust. PATIENTS: Overall, 266 individuals, including healthy men and women (n = 142) and those with reproductive disorders and states (n = 124 [11 with functional hypothalamic amenorrhoea, 6 with polycystic ovary syndrome, 62 women and 32 men with hypoactive sexual desire disorder, and 13 postmenopausal women]), were included in the analysis. INTERVENTIONS: Data from 266 individuals who had undergone detailed hormonal sampling in the saline placebo-treated arms of previous research studies was used to quantify the variability in reproductive hormones because of pulsatile secretion, diurnal variation, and feeding using coefficient of variation (CV) and entropy. MAIN OUTCOME MEASURES: The ability of a single measure of reproductive hormone level to quantify the variability in reproductive hormone levels because of pulsatile secretion, diurnal variation, and nutrient intake. RESULTS: The initial morning value of reproductive hormone levels was typically higher than the mean value throughout the day (percentage decrease from initial morning measure to daily mean: luteinizing hormone level 18.4%, follicle-stimulating hormone level 9.7%, testosterone level 9.2%, and estradiol level 2.1%). Luteinizing hormone level was the most variable (CV 28%), followed by sex-steroid hormone levels (testosterone level 12% and estradiol level 13%), whereas follicle-stimulating hormone level was the least variable reproductive hormone (CV 8%). In healthy men, testosterone levels fell between 9:00 am and 5:00 pm by 14.9% (95% confidence interval 4.2, 25.5%), although morning levels correlated with (and could be predicted from) late afternoon levels in the same individual (r2 = 0.53, P<.0001). Testosterone levels were reduced more after a mixed meal (by 34.3%) than during ad libitum feeding (9.5%), after an oral glucose load (6.0%), or an intravenous glucose load (7.4%). CONCLUSION: Quantification of the variability of a single measure of reproductive hormone levels informs the reliability of reproductive hormone assessment.


Assuntos
Hormônio Foliculoestimulante , Hormônio Luteinizante , Masculino , Humanos , Feminino , Estudos Retrospectivos , Reprodutibilidade dos Testes , Testosterona , Estradiol , Glucose
4.
Lancet Healthy Longev ; 4(10): e561-e572, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37804846

RESUMO

BACKGROUND: Testosterone replacement therapy is known to improve sexual function in men younger than 40 years with pathological hypogonadism. However, the extent to which testosterone alleviates sexual dysfunction in older men and men with obesity is unclear, despite the fact that testosterone is being increasingly prescribed to these patient populations. We aimed to evaluate whether subgroups of men with low testosterone derive any symptomatic benefit from testosterone treatment. METHODS: We did a systematic review and meta-analysis to evaluate characteristics associated with symptomatic benefit of testosterone treatment versus placebo in men aged 18 years and older with a baseline serum total testosterone concentration of less than 12 nmol/L. We searched major electronic databases (MEDLINE, Embase, Science Citation Index, and the Cochrane Central Register of Controlled Trials) and clinical trial registries for reports published in English between Jan 1, 1992, and Aug 27, 2018. Anonymised individual participant data were requested from the investigators of all identified trials. Primary (cardiovascular) outcomes from this analysis have been published previously. In this report, we present the secondary outcomes of sexual function, quality of life, and psychological outcomes at 12 months. We did a one-stage individual participant data meta-analysis with a random-effects linear regression model, and a two-stage meta-analysis integrating individual participant data with aggregated data from studies that did not provide individual participant data. This study is registered with PROSPERO, CRD42018111005. FINDINGS: 9871 citations were identified through database searches. After exclusion of duplicates and publications not meeting inclusion criteria, 225 full texts were assessed for inclusion, of which 109 publications reporting 35 primary studies (with a total 5601 participants) were included. Of these, 17 trials provided individual participant data (3431 participants; median age 67 years [IQR 60-72]; 3281 [97%] of 3380 aged ≥40 years) Compared with placebo, testosterone treatment increased 15-item International Index of Erectile Function (IIEF-15) total score (mean difference 5·52 [95% CI 3·95-7·10]; τ2=1·17; n=1412) and IIEF-15 erectile function subscore (2·14 [1·40-2·89]; τ2=0·64; n=1436), reaching the minimal clinically important difference for mild erectile dysfunction. These effects were not found to be dependent on participant age, obesity, presence of diabetes, or baseline serum total testosterone. However, absolute IIEF-15 scores reached during testosterone treatment were subject to thresholds in patient age and baseline serum total testosterone. Testosterone significantly improved Aging Males' Symptoms score, and some 12-item or 36-item Short Form Survey quality of life subscores compared with placebo, but it did not significantly improve psychological symptoms (measured by Beck Depression Inventory). INTERPRETATION: In men aged 40 years or older with baseline serum testosterone of less than 12 nmol/L, short-to-medium-term testosterone treatment could provide clinically meaningful treatment for mild erectile dysfunction, irrespective of patient age, obesity, or degree of low testosterone. However, due to more severe baseline symptoms, the absolute level of sexual function reached during testosterone treatment might be lower in older men and men with obesity. FUNDING: National Institute for Health and Care Research Health Technology Assessment Programme.


Assuntos
Disfunção Erétil , Hipogonadismo , Humanos , Masculino , Disfunção Erétil/tratamento farmacológico , Hipogonadismo/tratamento farmacológico , Obesidade/tratamento farmacológico , Qualidade de Vida , Testosterona/uso terapêutico
6.
Lancet Healthy Longev ; 3(6): e381-e393, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35711614

RESUMO

Background: Testosterone is the standard treatment for male hypogonadism, but there is uncertainty about its cardiovascular safety due to inconsistent findings. We aimed to provide the most extensive individual participant dataset (IPD) of testosterone trials available, to analyse subtypes of all cardiovascular events observed during treatment, and to investigate the effect of incorporating data from trials that did not provide IPD. Methods: We did a systematic review and meta-analysis of randomised controlled trials including IPD. We searched MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE Epub Ahead of Print, Embase, Science Citation Index, the Cochrane Controlled Trials Register, Cochrane Database of Systematic Reviews, and Database of Abstracts of Review of Effects for literature from 1992 onwards (date of search, Aug 27, 2018). The following inclusion criteria were applied: (1) men aged 18 years and older with a screening testosterone concentration of 12 nmol/L (350 ng/dL) or less; (2) the intervention of interest was treatment with any testosterone formulation, dose frequency, and route of administration, for a minimum duration of 3 months; (3) a comparator of placebo treatment; and (4) studies assessing the pre-specified primary or secondary outcomes of interest. Details of study design, interventions, participants, and outcome measures were extracted from published articles and anonymised IPD was requested from investigators of all identified trials. Primary outcomes were mortality, cardiovascular, and cerebrovascular events at any time during follow-up. The risk of bias was assessed using the Cochrane Risk of Bias tool. We did a one-stage meta-analysis using IPD, and a two-stage meta-analysis integrating IPD with data from studies not providing IPD. The study is registered with PROSPERO, CRD42018111005. Findings: 9871 citations were identified through database searches and after exclusion of duplicates and of irrelevant citations, 225 study reports were retrieved for full-text screening. 116 studies were subsequently excluded for not meeting the inclusion criteria in terms of study design and characteristics of intervention, and 35 primary studies (5601 participants, mean age 65 years, [SD 11]) reported in 109 peer-reviewed publications were deemed suitable for inclusion. Of these, 17 studies (49%) provided IPD (3431 participants, mean duration 9·5 months) from nine different countries while 18 did not provide IPD data. Risk of bias was judged to be low in most IPD studies (71%). Fewer deaths occurred with testosterone treatment (six [0·4%] of 1621) than placebo (12 [0·8%] of 1537) without significant differences between groups (odds ratio [OR] 0·46 [95% CI 0·17-1·24]; p=0·13). Cardiovascular risk was similar during testosterone treatment (120 [7·5%] of 1601 events) and placebo treatment (110 [7·2%] of 1519 events; OR 1·07 [95% CI 0·81-1·42]; p=0·62). Frequently occurring cardiovascular events included arrhythmia (52 of 166 vs 47 of 176), coronary heart disease (33 of 166 vs 33 of 176), heart failure (22 of 166 vs 28 of 176), and myocardial infarction (10 of 166 vs 16 of 176). Overall, patient age (interaction 0·97 [99% CI 0·92-1·03]; p=0·17), baseline testosterone (interaction 0·97 [0·82-1·15]; p=0·69), smoking status (interaction 1·68 [0·41-6·88]; p=0.35), or diabetes status (interaction 2·08 [0·89-4·82; p=0·025) were not associated with cardiovascular risk. Interpretation: We found no evidence that testosterone increased short-term to medium-term cardiovascular risks in men with hypogonadism, but there is a paucity of data evaluating its long-term safety. Long-term data are needed to fully evaluate the safety of testosterone. Funding: National Institute for Health Research Health Technology Assessment Programme.


Assuntos
Insuficiência Cardíaca , Hipogonadismo , Infarto do Miocárdio , Idoso , Humanos , Masculino , Revisões Sistemáticas como Assunto , Testosterona
7.
Prim Health Care Res Dev ; 12(2): 83-94, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21457594

RESUMO

BACKGROUND: Obesity is a major public health issue because of its increasing prevalence and impact on health. The management of overweight and obesity has been a government priority for many years. However, overweight and obesity management at a local level has often been ineffective. Although there is a need to examine obesity strategies and policies for local populations, there is currently no readily available framework for evaluating local obesity strategies. We therefore developed a framework, the Imperial College Obesity Strategy Assessment Framework (IC-OSAF), for examining the content of local obesity strategies. METHODS: We adapted two previous policy analysis frameworks (Bardach's Eightfold Path Framework and Collins' Health Policy Analysis Framework) and used these with information from national guidelines to develop an obesity strategy analysis framework. We then piloted this framework using the obesity strategy for one London primary care trust (PCT). RESULTS: The framework was applied successfully and helped identify limitations and omissions in the PCT obesity management strategy. CONCLUSIONS: The IC-OSAF is a practical, easy-to-use tool for the analysis of local obesity management strategies. The framework can help identify gaps and limitations in strategies to help reduce variations in obesity management between PCTs.


Assuntos
Política de Saúde , Obesidade/prevenção & controle , Formulação de Políticas , Desenvolvimento de Programas , Humanos , Londres , Modelos Teóricos , Atenção Primária à Saúde
8.
Clin Endocrinol (Oxf) ; 73(3): 369-74, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20550538

RESUMO

OBJECTIVE: Cabergoline is a highly effective medical treatment for patients with hyperprolactinaemia. There is an increased risk of valvular heart disease in patients receiving cabergoline for Parkinson's disease. This study examined whether cabergoline treatment of hyperprolactinaemia is associated with a greater prevalence of valvulopathy. DESIGN: Cross-sectional, two-dimensional echocardiographic study performed by a single echocardiographer. PATIENTS: Seventy-two patients (median age 36 years, 19 men) receiving cabergoline for hyperprolactinaemia, and 72 controls prospectively matched for age, sex and cardiovascular risk factors. Measurements Assessment of valvular mobility, regurgitation and morphology. RESULTS: Median cumulative dose exposure for cabergoline was 126 (58-258) mg, and patients had received cabergoline for 53 (26-96) months. The frequency of mild mitral regurgitation was identical (5/72, 7%) in patient and control groups. Mild aortic regurgitation was not significantly different between groups (4/72 [controls] vs 2/72 [patients], P = 0.681). There was only one case of tricuspid regurgitation, which was mild and observed in a cabergoline-treated patient. Nodular thickening of the right coronary cusp, noncoronary cusp or left coronary cusp of the aortic valve was observed at a similar frequency in both groups. There were no cases of extensive thickening of any valvular leaflet. CONCLUSION: Our data demonstrates that there is no association between cabergoline treatment for hyperprolactinaemia and valvulopathy. This study therefore supports continued use of low-dose cabergoline for patients with hyperprolactinaemia.


Assuntos
Ergolinas/uso terapêutico , Doenças das Valvas Cardíacas/fisiopatologia , Valvas Cardíacas/fisiopatologia , Hiperprolactinemia/tratamento farmacológico , Adulto , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Pressão Sanguínea , Cabergolina , Estudos Transversais , Relação Dose-Resposta a Droga , Ecocardiografia , Ergolinas/efeitos adversos , Feminino , Doenças das Valvas Cardíacas/induzido quimicamente , Doenças das Valvas Cardíacas/diagnóstico , Valvas Cardíacas/diagnóstico por imagem , Valvas Cardíacas/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco/métodos , Função Ventricular Esquerda , Função Ventricular Direita
9.
Endocrinology ; 145(11): 5252-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15297436

RESUMO

Increased food intake is characteristic of hyperthyroidism, although this is presumed to compensate for a state of negative energy balance. However, here we show that the thyroid hormone T(3) directly stimulates feeding at the level of the hypothalamus. Peripheral administration of T(3) doubled food intake in ad libitum-fed rats over 2 h and induced expression of the immediate early gene, early growth response-1, in the hypothalamic ventromedial nucleus (VMN), whereas maintaining plasma-free T(3) levels within the normal range. T(3)-induced feeding occurred without altering energy expenditure or locomotion. Injection of T(3) directly into the VMN produced a 4-fold increase in food intake in the first hour. The majority of T(3) in the brain is reported to be produced by tissue-specific conversion of T(4) to T(3) by the enzyme type 2 iodothyronine deiodinase (D2). Hypothalamic D2 mRNA expression showed a diurnal variation, with a peak in the nocturnal feeding phase. Hypothalamic D2 mRNA levels also increased after a 12- and 24-h fast, suggesting that local production of T(3) may play a role in this T(3) feeding circuit. Thus, we propose a novel hypothalamic feeding circuit in which T(3), from the peripheral circulation or produced by local conversion, stimulates food intake via the VMN.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Hipertireoidismo/fisiopatologia , Tri-Iodotironina/farmacologia , Núcleo Hipotalâmico Ventromedial/fisiologia , Tecido Adiposo/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Jejum/fisiologia , Regulação Enzimológica da Expressão Gênica , Iodeto Peroxidase/genética , Leptina/sangue , Masculino , RNA Mensageiro/análise , Ratos , Ratos Wistar , Tiroxina/sangue , Iodotironina Desiodinase Tipo II
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA