13 research outputs found
Genome-wide association study with 1000 genomes imputation identifies signals for nine sex hormone-related phenotypes.
PublishedJournal ArticleResearch Support, Non-U.S. Gov'tThis is the final version of the article. Available from Nature Publishing Group via the DOI in this record.Genetic factors contribute strongly to sex hormone levels, yet knowledge of the regulatory mechanisms remains incomplete. Genome-wide association studies (GWAS) have identified only a small number of loci associated with sex hormone levels, with several reproductive hormones yet to be assessed. The aim of the study was to identify novel genetic variants contributing to the regulation of sex hormones. We performed GWAS using genotypes imputed from the 1000 Genomes reference panel. The study used genotype and phenotype data from a UK twin register. We included 2913 individuals (up to 294 males) from the Twins UK study, excluding individuals receiving hormone treatment. Phenotypes were standardised for age, sex, BMI, stage of menstrual cycle and menopausal status. We tested 7,879,351 autosomal SNPs for association with levels of dehydroepiandrosterone sulphate (DHEAS), oestradiol, free androgen index (FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, progesterone, sex hormone-binding globulin and testosterone. Eight independent genetic variants reached genome-wide significance (P<5 × 10(-8)), with minor allele frequencies of 1.3-23.9%. Novel signals included variants for progesterone (P=7.68 × 10(-12)), oestradiol (P=1.63 × 10(-8)) and FAI (P=1.50 × 10(-8)). A genetic variant near the FSHB gene was identified which influenced both FSH (P=1.74 × 10(-8)) and LH (P=3.94 × 10(-9)) levels. A separate locus on chromosome 7 was associated with both DHEAS (P=1.82 × 10(-14)) and progesterone (P=6.09 × 10(-14)). This study highlights loci that are relevant to reproductive function and suggests overlap in the genetic basis of hormone regulation.We thank Roche Diagnostics Australia Pty Limited, Castle Hill, Australia, who provided support for the analysis of the hormones. We thank the volunteer twins for their participation in the study. Twins UK received funding support from NIHR Biomedical Research Centre (grant to Guys’ and St Thomas’ Hospitals and King’s College London); the Chronic Disease Research Foundation; Canadian Institutes of Health Research, the Canadian Foundation for Innovation, the Fonds de la Recherche en Santé Québec, The Lady Davis Institute, the Jewish General Hospital and Ministère du Développement économique, de l'Innovation et de l'Exportation du Quebec. The Australian National Health and Medical Research Council (NHMRC project grants 1010494, 1048216), and Sir Charles Gairdner Hospital Research (grant PP2009/028). This work was supported by funding from the Wellcome Trust (092447/Z/10/Z) and Medical Research Council (MC_U106179472)
Erectile dysfunction in general medicine practice: prevalence and clinical correlates
Erectile dysfunction (ED) is a common problem in general medical practice affecting especially the elderly and those with cardiovascular disease and diabetes mellitus, A study was undertaken by questionnaire distributed to consecutive adult male attendees at 62 general medical practices. 1240 completed questionnaires were available for analysis. The mean age of participants was 56.4 y (range 18 - 91 y). 488 men (39.4%) reported ED: 119 (9.6%) 'occasionally', 110 (8.9%) 'often', and 231 (18.6%) 'all the time' (complete ED). Among 707 men aged 40-69 y 240 (33.9%) reported ED and 84 (11.9%) had complete ED. The prevalence of complete ED increased with age, rising from 2.0% in the 40-49 y age group to 44.9% in the 70-79 y age group. Only 11.6% of men with ED had received treatment. Hypertension, ischaemic heart disease, peripheral vascular disease and diabetes mellitus were frequently associated with ED. 40% of diabetic men aged 60 y or older had ED all the time
Sildenafil citrate for treatment of erectile dysfunction in men with type 1 diabetes - Results of a randomized controlled trial
OBJECTIVE - In the 5-10% of diabetic men with type I diabetes, erectile dysfunction (ED) may be a particularly common and unwanted complication. This is the first study focusing exclusively on the effects of sildenafil in men with type 1 diabetes and ED
Alendronate prevents loss of bone density associated with discontinuation of hormone replacement therapy
GesondheidswetenskappeInterne GeneeskundePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]
Alendronate prevents loss of bone density associated with discontinuation of hormone replacement therapy
GesondheidswetenskappeInterne GeneeskundePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]
Recovery of Male Reproductive Endocrine Function Following Prolonged Injectable Testosterone Undecanoate Treatment
Abstract
Background: Exogenous androgen treatment suppresses the hypothalamo-pituitary testicular (HPT) axis causing reduced serum LH, FSH and testosterone (T). Recovery of male reproductive endocrine function in past androgen abusers takes 9-18 months with persistent mild lowering of serum T. The natural history of recovery of HPT axis following prolonged injectable testosterone undecanoate (TU) treatment at standard dose is not known. Therefore, the Runoff Study investigated the rate and extent of reproductive hormone recovery over 12 months following cessation of 2 years of TU treatment in the Testosterone for Diabetes Mellitus (T4DM) Study, while men remain blinded to treatment allocation. Methods: T4DM participants without pathological hypogonadism (n=1007) were randomised to TU or Placebo (P) injections every 3 months for 2 years with 303 subsequently volunteering to enter the Runoff study at 12 weeks after last injection. Before T4DM study unblinding, they provided blood samples and validated sexual function questionnaires (PDQ, IIEF-15) at entry (3 months after last injection), 6, 12, 18, 24, 40 and 52 weeks later. Serum steroid profile (T, DHT, E2, E1) was measured batchwise by LCMS and serum LH, FSH and SHBG by immunoassays. Results: Runoff study participants in both groups were similar and did not differ from all T4DM participants. As expected, at entry to Runoff serum T was higher in TU-treated men but at all timepoints from 12 weeks onwards serum T and SHBG remained consistently 11% and 13%, respectively, lower in TU-treated than in P-treated men. Similarly, at entry sexual function scores were higher in TU-treated men but subsequently no different from P-treated men. Serum LH and FSH recovered slowly with the median time to reach their own pre-treatment baseline of serum LH was 51.1 weeks [95% CI 50.4 – 53.0 weeks] and for serum FSH was 52.7 weeks [51.0 – 60.9 weeks]. Conclusion: After stopping 2 years of standard dose injectable TU treatment in men without pathological hypogonadism, recovery of testicular endocrine function is eventually complete but slow with serum gonadotropin recovery taking on 12 months since the last dose. Persistent mild, proportionate reduction in serum SHBG and T reflects lasting exogenous T effects on hepatic SHBG secretion rather than signifying androgen deficiency. This suggests that recovery from androgen-induced HPT axis suppression depends primarily on time since cessation rather than dose or duration of androgen exposure
Calcium absorption in postmenopausal osteoporosis: Benefit of HRT plus calcitriol, but not HRT alone, in both malabsorbers and normal absorbers
In a randomized trial involving 71 postmenopausal osteoporotic women with vertebral compression fractures, radiocalcium absorption studies using the Ca-45 single isotope method (alpha) were performed at baseline and after 8 months of treatment with either continuous combined hormone replacement therapy (HRT, as piperazine estrone sulfate 0.625-0.937mg daily +/- medroxyprogesterone acetate 2.5 mg daily depending on uterine status) or HRT plus calcitriol 0.25 mu g twice daily. A calcium supplement of 600 mg nocte was given to only those women who had a daily calcium intake of less than 1 g per day at baseline, as assessed by recalled dietary intake. There was a significant decrease 0.74 (+/- 0.35 SD) to 0.58 (+/- 0.22), Delta alpha = -0.17 (+/- 0.26), p<0.0005] in alpha at 8 months compared with baseline in the HRT-treated group, but a significant increase [0.68 (+/- 0.31) to 0.84 (+/- 0.27), Delta alpha = +0.16 (+/- 0.30), p<0.003] in the HRT-plus-calcitriol treated patients, resulting in alpha being significantly higher after 8 months in the latter group than in the HRT-only group. Although 72% of the patients had been supplemented with calcium between the first and second studies, separate analyses revealed that the change in calcium intake had not affected the result. Further breakdown of the groups into baseline 'normal' absorbers (alpha greater than or equal to 0.55) and 'malabsorbers' (alpha <0.55) revealed that alpha decreased with HRT treatment only in the normal absorbers, and remained stable in the malabsorbers. Conversely, following HRT plus calcitriol treatment, alpha increased only in the malabsorbers, the normal absorbers in this group remaining unchanged. In conclusion, our data show that HRT, of the type and dose used in this study, did not produce an increase in absorption efficiency; it was in fact associated with a fall. increased absorption efficiency cannot be achieved unless calcitriol is used concurrently, and then only in patients with malabsorption. Calcitriol also had a significant effect in normal absorbers in that it prevented the decline in alpha seen with HRT alone, and thus should be considered in all patients with postmenopausal osteoporosis treated with HRT
Large-scale genome-wide meta-analysis of polycystic ovary syndrome suggests shared genetic architecture for different diagnosis criteria
Polycystic ovary syndrome (PCOS) is a disorder characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology. Affected women frequently have metabolic disturbances including insulin resistance and dysregulation of glucose homeostasis. PCOS is diagnosed with two different sets of diagnostic criteria, resulting in a phenotypic spectrum of PCOS cases. The genetic similarities between cases diagnosed based on the two criteria have been largely unknown. Previous studies in Chinese and European subjects have identified 16 loci associated with risk of PCOS. We report a fixed-effect, inverse-weighted-variance meta-analysis from 10,074 PCOS cases and 103,164 controls of European ancestry and characterisation of PCOS related traits. We identified 3 novel loci (near PLGRKT, ZBTB16 and MAPRE1), and provide replication of 11 previously reported loci. Only one locus differed significantly in its association by diagnostic criteria; otherwise the genetic architecture was similar between PCOS diagnosed by self-report and PCOS diagnosed by NIH or non-NIH Rotterdam criteria across common variants at 13 loci. Identified variants were associated with hyperandrogenism, gonadotropin regulation and testosterone levels in affected women. Linkage disequilibrium score regression analysis revealed genetic correlations with obesity, fasting insulin, type 2 diabetes, lipid levels and coronary artery disease, indicating shared genetic architecture between metabolic traits and PCOS. Mendelian randomization analyses suggested variants associated with body mass index, fasting insulin, menopause timing, depression and male-pattern balding play a causal role in PCOS. The data thus demonstrate 3 novel loci associated with PCOS and similar genetic architecture for all diagnostic criteria. The data also provide the first genetic evidence for a male phenotype for PCOS and a causal link to depression, a previously hypothesized comorbid disease. Thus, the genetics provide a comprehensive view of PCOS that encompasses multiple diagnostic criteria, gender, reproductive potential and mental health