Effects of Estrogen Therapies on Outcomes in Turner Syndrome: Assessment of Induction of Puberty and Adult Estrogen Use

Society for endocrinology guideline for understanding, diagnosing and treating female hypogonadism

Female hypogonadism (FH) is a relatively common endocrine disorder in women of premenopausal age, but there are significant uncertainties and wide variation in its management. Most current guidelines are monospecialty and only address premature ovarian insufficiency (POI); some allude to management in very brief and general terms, and most rely upon the extrapolation of evidence from the studies relating to physiological estrogen deficiency in postmenopausal women. The Society for Endocrinology commissioned new guidance to provide all care providers with a multidisciplinary perspective on managing patients with all forms of FH. It has been compiled using expertise from Endocrinology, Primary Care, Gynaecology and Reproductive Health practices, with contributions from expert patients and a patient support group, to help clinicians best manage FH resulting from both POI and hypothalamo-pituitary disorders, whether organic or functional.

Bone mineral density: Comparison between women under hormone replacement therapy with Turner syndrome or idiopathic premature ovarian insufficiency

CONTEXT

Turner syndrome (TS) is characterized by short stature and premature ovarian insufficiency (POI). The main long-term complication of POI is osteoporosis, which can be prevented by hormone replacement therapy (HRT).

OBJECTIVE

The objective of our study was to compare initial bone mineral density (BMD) and progression between TS and idiopathic POI patients under HRT.

METHODS

A single-center retrospective study was conducted between 1998 and 2018. All women had undergone at least two bone densitometry assessments at least 2 years apart.

RESULTS

Sixty-eight TS patients and 67 idiopathic POI patients were included. Mean age at initial assessment was 27 years (IQR, 21-35.5 years) in TS patients and 31.5 years (IQR, 23-37 years) in idiopathic POI patients (P=0.1). Lumbar and femoral neck BMD were lower in the TS group than in the idiopathic POI group (respectively 0.89g/cm2 versus 0.95g/cm2, P=0.03; 0.70g/cm2 versus 0.77g/cm2, P<0.0001). Mosaic karyotype was associated with better BMD in TS patients while history of growth hormone treatment had no impact on BMD. Over time, a significant gain in vertebral BMD was observed in TS patients versus a loss of BMD in idiopathic POI patients (P=0.0009).

CONCLUSION

TS patients had a lower BMD at baseline than idiopathic POI patients, at both spinal and femoral levels. Over time, on HRT, a significant gain in vertebral BMD was observed in patients with TS, compared with a loss of BMD in patients with idiopathic POI. We hypothesized that earlier initiation and longer duration of HRT played an important role in this finding. Long-term prospective follow-up to assess the incidence of fractures in TS would be useful.

Transition from pediatric to adult care in patients with Turner syndrome in Italy: a consensus statement by the TRAMITI project

PURPOSE

Transition from pediatric to adult care is associated with significant challenges in patients with Turner syndrome (TS). The objective of the TRansition Age Management In Turner syndrome in Italy (TRAMITI) project was to improve the care provided to patients with TS by harnessing the knowledge and expertise of various Italian centers through a Delphi-like consensus process.

METHODS

A panel of 15 physicians and 1 psychologist discussed 4 key domains: transition and referral, sexual and bone health and oncological risks, social and psychological aspects and systemic and metabolic disorders.

RESULTS

A total of 41 consensus statements were drafted. The transition from pediatric to adult care is a critical period for patients with TS, necessitating tailored approaches and early disclosure of the diagnosis to promote self-reliance and healthcare autonomy. Fertility preservation and bone health strategies are recommended to mitigate long-term complications, and psychiatric evaluations are recommended to address the increased prevalence of anxiety and depression. The consensus also addresses the heightened risk of metabolic, cardiovascular and autoimmune disorders in patients with TS; regular screenings and interventions are advised to manage these conditions effectively. In addition, cardiac abnormalities, including aortic dissections, require regular monitoring and early surgical intervention if certain criteria are met.

CONCLUSIONS

The TRAMITI consensus statement provides valuable insights and evidence-based recommendations to guide healthcare practitioners in delivering comprehensive and patient-centered care for patients with TS. By addressing the complex medical and psychosocial aspects of the condition, this consensus aims to enhance TS management and improve the overall well-being and long-term outcomes of these individuals.

Factors associated with low bone mineral density in Turner syndrome: a multicenter prospective observational study

Turner syndrome (TS) is associated with a high risk of fracture due to low bone mineral density (BMD). While hypogonadism is known to play a role in decreasing BMD, other factors have not been studied well. Focusing on diet, exercise, and bone metabolism markers, the present, multicentric, prospective, observational study aimed to identify factors contributing to decreased BMD in TS. In total, 48 patients with TS aged between 5 and 49 years comprising a pre-pubertal group (n = 9), a cyclical menstruation group (n = 6), and a hormone replacement therapy (HRT) group (n = 33) were enrolled. The cyclical menstruation group and the HRT group were referred to collectively as the post-pubertal group. The bone mineral apparent density (BMAD) Z-score was higher in the pre-pubertal group than in the post-pubertal group (-0.3 SD vs. -1.8 SD; p = 0.014). Within the post-pubertal group, the median BMAD Z-score was -0.2 SD in the cyclical menstruation group and -2.3 SD in the HRT group (p = 0.016). Spearman's rank correlation revealed no correlation between the BMAD Z-score and bone metabolism markers. No significant relationship was observed between the BMAD Z-score and either the vitamin D sufficiency rate or the step sufficiency rate. A negative correlation was found between BMAD Z-score and serum sclerostin in the pre-pubertal group and serum FSH in the post-pubertal group. In conclusion, the present study found no relationship between the vertebral BMAD Z-score and diet or exercise habits in TS, indicating that estrogen deficiency is the chief reason for low BMD in TS.

Clinical practice guidelines for the care of girls and women with Turner syndrome

Turner syndrome (TS) affects 50 per 100 000 females. TS affects multiple organs through all stages of life, necessitating multidisciplinary care. This guideline extends previous ones and includes important new advances, within diagnostics and genetics, estrogen treatment, fertility, co-morbidities, and neurocognition and neuropsychology. Exploratory meetings were held in 2021 in Europe and United States culminating with a consensus meeting in Aarhus, Denmark in June 2023. Prior to this, eight groups addressed important areas in TS care: (1) diagnosis and genetics, (2) growth, (3) puberty and estrogen treatment, (4) cardiovascular health, (5) transition, (6) fertility assessment, monitoring, and counselling, (7) health surveillance for comorbidities throughout the lifespan, and (8) neurocognition and its implications for mental health and well-being. Each group produced proposals for the present guidelines, which were meticulously discussed by the entire group. Four pertinent questions were submitted for formal GRADE (Grading of Recommendations, Assessment, Development and Evaluation) evaluation with systematic review of the literature. The guidelines project was initiated by the European Society for Endocrinology and the Pediatric Endocrine Society, in collaboration with members from the European Society for Pediatric Endocrinology, the European Society of Human Reproduction and Embryology, the European Reference Network on Rare Endocrine Conditions, the Society for Endocrinology, and the European Society of Cardiology, Japanese Society for Pediatric Endocrinology, Australia and New Zealand Society for Pediatric Endocrinology and Diabetes, Latin American Society for Pediatric Endocrinology, Arab Society for Pediatric Endocrinology and Diabetes, and the Asia Pacific Pediatric Endocrine Society. Advocacy groups appointed representatives for pre-meeting discussions and the consensus meeting.

Effects of Hormone Replacement Therapy on Bone Mineral Density in Korean Adults With Turner Syndrome

BACKGROUND

Turner syndrome (TS) is a common chromosomal abnormality, which is caused by loss of all or part of one X chromosome. Hormone replacement therapy in TS is important in terms of puberty, growth and prevention of osteoporosis however, such a study has never been conducted in Korea. Therefore, the purpose of our study was to determine relationship between the starting age, duration of estrogen replacement therapy (ERT) in TS and develop a hormone replacement protocol suitable for the situation in Korea.

METHODS

This is retrospective study analyzed the medical records in TS patients treated at the Severance hospital, Yonsei University College of Medicine, Seoul, Korea from 1997 to 2019. Total of 188 subjects who had received a bone density test at least once were included in the study. Korean National Health and Nutrition Examination Survey (KNHANES) was used for achieving bone mineral density (BMD) of normal control group. Student's t-test, Mann-Whitney U test, ANOVA and correlation analysis were performed using SPSS 18.0.

RESULTS

Each BMD measurement was significantly lower in women with TS than in healthy Korean women. Early start and longer duration of ERT is associated with higher lumbar spine BMD but not femur neck BMD. Femur neck BMD, but not lumbar spine BMD was significantly higher in women with mosaicism than 45XO group.

CONCLUSION

Early onset and appropriate duration of hormone replacement therapy is important for increasing bone mineral density in patients with Turner syndrome. Also, ERT affects differently to TS patients according to mosaicism.

Focus on Liver Function Abnormalities in Patients With Turner Syndrome: Risk Factors and Evaluation of Fibrosis Risk

CONTEXT

Liver function abnormalities (LFAs) have been described in patients with Turner syndrome (TS). Although a high risk of cirrhosis has been reported, there is a need to assess the severity of liver damage in a large cohort of adult patients with TS.

OBJECTIVE

Evaluate the types of LFAs and their respective prevalence, search for their risk factors, and evaluate the severity of liver impairment by using a noninvasive fibrosis marker.

METHODS

This was a monocentric retrospective cross-sectional study. Data were collected during a day hospital visit. The main outcome measures were liver enzymes (alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase), FIB-4 score, liver ultrasound imaging, elastography, and liver biopsies, when available.

RESULTS

264 patients with TS were evaluated at a mean age of 31.15 ± 11.48 years. The overall prevalence of LFAs was 42.8%. The risk factors were age, body mass index, insulin resistance, and an X isochromosome (Xq). The mean FIB-4 sore of the entire cohort was 0.67 ± 0.41. Less than 10% of patients were at risk of developing fibrosis. Cirrhosis was observed in 2/19 liver biopsies. There was no significant difference in the prevalence of LFAs between premenopausal patients with natural cycles and those receiving hormone replacement therapy (P = .063). A multivariate analysis adjusted for age showed no statistically significant correlation between hormone replacement therapy and abnormal gamma-glutamyl transferase levels (P = .12).

CONCLUSION

Patients with TS have a high prevalence of LFA. However, 10% are at high risk of developing fibrosis. The FIB-4 score is useful and should be part of the routine screening strategy. Longitudinal studies and better interactions with hepatologists should improve our knowledge of liver disease in patients with TS.

Organ Abnormalities Caused by Turner Syndrome

Turner syndrome (TS), a genetic disorder due to incomplete dosage compensation of X-linked genes, affects multiple organ systems, leading to hypogonadotropic hypogonadism, short stature, cardiovascular and vascular abnormalities, liver disease, renal abnormalities, brain abnormalities, and skeletal problems. Patients with TS experience premature ovarian failure with a rapid decline in ovarian function caused by germ cell depletion, and pregnancies carry a high risk of adverse maternal and fetal outcomes. Aortic abnormalities, heart defects, obesity, hypertension, and liver abnormalities, such as steatosis, steatohepatitis, biliary involvement, liver cirrhosis, and nodular regenerative hyperplasia, are commonly observed in patients with TS. The SHOX gene plays a crucial role in short stature and abnormal skeletal phenotype in patients with TS. Abnormal structure formation of the ureter and kidney is also common in patients with TS, and a non-mosaic 45,X karyotype is significantly associated with horseshoe kidneys. TS also affects brain structure and function. In this review, we explore various phenotypic and disease manifestations of TS in different organs, including the reproductive system, cardiovascular system, liver, kidneys, brain, and skeletal system.

Pubertal induction in Turner syndrome without gonadal function: A possibility of earlier, lower-dose estrogen therapy

Delayed and absent puberty and infertility in Turner syndrome (TS) are caused by primary hypogonadism. A majority of patients with TS who are followed at hospitals during childhood will not experience regular menstruation. In fact, almost all patients with TS need estrogen replacement therapy (ERT) before they are young adults. ERT in TS is administered empirically. However, some practical issues concerning puberty induction in TS require clarification, such as how early to start ERT. The present monograph aims to review current pubertal induction therapies for TS without endogenous estrogen production and suggests a new therapeutic approach using a transdermal estradiol patch that mimics incremental increases in circulating, physiological estradiol. Although evidence supporting this approach is still scarce, pubertal induction with earlier, lower-dose estrogen therapy more closely approximates endogenous estradiol secretion.

The effect of the rate of increase of estrogen replacement therapy on bone mineral density accrual in young patients with Turner syndrome

BACKGROUND

Turner syndrome (TS) is caused by partial/complete X-chromosome monosomy with variable phenotypes, characterized by hypogonadism and short stature. To achieve pubertal changes, up to 50-79% of patients with TS require estrogen replacement therapy (ERT) and 80% have low bone mineral density (BMD). Studies show that pubertal delays are associated with decreased BMD. Currently, guidelines suggest ERT start at 12 years, increasing slowly, simulating pubertal progression. Many studies show that ERT increases BMD in TS adolescents, but uncertainty remains as to how the rate of increase in ERT affects BMD.

METHODS

IRB approval was obtained from our institution for this retrospective chart review from 1991-2020. Charts were requested for the database using ICD 9-10 codes for TS and patients undergoing dual-energy X-ray absorptiometry (DEXA). Biometric data, medical and treatment histories were extracted from charts. Multilevel random effects models were constructed to assess the time dependent associations between ERT and bone density parameters. The primary independent variable of interest was the rate at which patients went from initiating ERT to reaching final doses. The primary dependent variables measured were total body BMD (tbBMD) and corresponding z-scores, calculated using DEXA techniques. Analyses were done with SAS software (version 9.4, Cary, NC).

RESULTS

28 patients met inclusion criteria. Mean age of TS diagnosis was 6.9 years; 8 patients had monosomy X, 16 had mosaic karyotypes, 4 had unknown karyotypes. The average age for starting HRT was 14.1 years. 13 patients had spontaneous pubertal onset before starting HRT. tbBMD increased significantly with age (p = 0.03). However, change in BMD by age does not vary between patients who reached final adult doses of ERT within 0-2.5 years, compared to patients who took 2.5-5.5 years (p=0.7). Patients who took 2.5-5.5 years to reach final adult doses of ERT had a more negative trend in z-scores (-2.144) in comparison to patients who took 0-2.5 years (-1.776), although this difference did not reach statistical significance (p=.15). Future larger studies are needed to better understand the relationship between duration of ERT use and tbBMD.

CONCLUSIONS

BMD in TS adolescents increases with age. Neither absolute tbBMD values nor tbBMD z-scores increased faster when ERT doses were maximized within 2.5 years. This study has identified a cohort of children under 12 years with TS who have not had any ERT or BMD measurements - a potential population for future larger prospective studies.

The Changing Face of Turner Syndrome

Turner syndrome (TS) is a condition in females missing the second sex chromosome (45,X) or parts thereof. It is considered a rare genetic condition and is associated with a wide range of clinical stigmata, such as short stature, ovarian dysgenesis, delayed puberty and infertility, congenital malformations, endocrine disorders, including a range of autoimmune conditions and type 2 diabetes, and neurocognitive deficits. Morbidity and mortality are clearly increased compared with the general population and the average age at diagnosis is quite delayed. During recent years it has become clear that a multidisciplinary approach is necessary toward the patient with TS. A number of clinical advances has been implemented, and these are reviewed. Our understanding of the genomic architecture of TS is advancing rapidly, and these latest developments are reviewed and discussed. Several candidate genes, genomic pathways and mechanisms, including an altered transcriptome and epigenome, are also presented.

Management of a Girl With Delayed Puberty and Elevated Gonadotropins

A girl presenting with delayed puberty and elevated gonadotropins may have a range of conditions such as Turner syndrome (TS), primary ovarian insufficiency (POI), and 46,XY disorders of sexual development (DSD). An organized and measured approach to investigation can help reach a timely diagnosis. Management of young people often requires specialist multidisciplinary input to address the endocrine and nonendocrine features of these complex conditions, as well as the psychological challenges posed by their diagnosis. Next-generation sequencing within the research setting has revealed several genetic causes of POI and 46,XY DSD, which may further facilitate an individualized approach to care of these young people in the future. Pubertal induction is required in many and the timing of this may need to be balanced with other issues specific to the condition (eg, allowing time for information-sharing in 46,XY DSD, optimizing growth in TS). Shared decision-making and sign-posting to relevant support groups from the outset can help empower young people and their families to manage these conditions. We describe 3 clinical vignettes of girls presenting with delayed puberty and hypergonadotropic amenorrhea and discuss their clinical management in the context of current literature and guidelines.

Liver abnormalities in Turner’s syndrome – the importance of estrogen replacement

Turner syndrome is one of the most frequently reported sex chromosomal abnormalities, affecting approximately 40 in every 100 000 live female births. The underlying chromosomal alteration is the complete or partial loss of X chromosome or mosaicism. Because of primary ovarian insufficiency, the synthesis of estrogen hormones is compromised, and patients require hormone substitution. Apart from the phenotypical presentation (short stature, primary amenorrhea), the effects of ovarian insufficiency can affect diverse organ systems (such as cardiovascular, endocrine, and lymphatic systems). Hepatobiliary pathology can present on a broad spectrum: from mild asymptomatic hypertransaminasemia to marked architectural changes. Estrogen hormone replacement therapy in these patients can improve the perturbations of laboratory values and can attenuate the progression of hepatic structural changes. Moreover, providing sufficient estrogen replacement has numerous benefits for other conditions of the patients as well. Both the all-cause mortality and deaths from cardiovascular complications are greatly increased in Turner syndrome, and hormone replacement might contribute to the decreased incidence of these events. The diagnostics of Turner syndrome are outside the scope of our paper, and we briefly discuss the cardiovascular complications because many the liver involvement partially involves alterations of vascular origin. Though we sought to highlight the importance of proper hormone replacement therapy, we did not attempt to write a comprehensive recommendation for exact treatment protocols. We provided an overview of preferred therapeutic approaches, as the treatment should be tailored according to the individual patient’s needs.

Skeletal Characteristics of Children and Adolescents with Turner Syndrome

Turner syndrome (TS) is a chromosomal disorder characterized by a short stature and gonadal dysgenesis, the latter of which requires estrogen replacement therapy (ERT) to induce and maintain secondary sexual characteristics. Insufficient ERT is associated with compromised skeletal health, including bone fragility, in adults with TS. In particular, estrogen insufficiency during adolescence is critical because the acquisition of a defective bone mass during this period results in impaired bone strength later in the life. In addition to bone mass, bone geometry is also a crucial factor influencing bone strength; therefore, a more detailed understanding of the skeletal characteristics of both bone mass and geometry during childhood and adolescence and their relationships with the estrogen status is needed to prevent compromised skeletal health during adulthood in TS. Although a delay in the initiation of ERT is associated with a lower bone mineral density during adulthood, limited information is currently available on the effects of ERT during adolescence on bone geometry. Herein, we summarize the current knowledge on skeletal characteristics in children and adolescents with TS and their relationships with estrogen sufficiency, and discuss the potential limitations of the current protocol for ERT during adolescence in order to achieve better skeletal health in adulthood.

Turner syndrome: French National Diagnosis and Care Protocol (NDCP; National Diagnosis and Care Protocol)

Turner syndrome (TS; ORPHA 881) is a rare condition in which all or part of one X chromosome is absent from some or all cells. It affects approximately one in every 1/2500 liveborn girls. The most frequently observed karyotypes are 45,X (40–50%) and the 45,X/46,XX mosaic karyotype (15–25%). Karyotypes with an X isochromosome (45,X/46,isoXq or 45,X/46,isoXp), a Y chromosome, X ring chromosome or deletions of the X chromosome are less frequent. The objective of the French National Diagnosis and Care Protocol (PNDS; Protocole National de Diagnostic et de Soins) is to provide health professionals with information about the optimal management and care for patients, based on a critical literature review and multidisciplinary expert consensus. The PNDS, written by members of the French National Reference Center for Rare Growth and Developmental Endocrine disorders, is available from the French Health Authority website. Turner Syndrome is associated with several phenotypic conditions and a higher risk of comorbidity. The most frequently reported features are growth retardation with short adult stature and gonadal dysgenesis. TS may be associated with various congenital (heart and kidney) or acquired diseases (autoimmune thyroid disease, celiac disease, hearing loss, overweight/obesity, glucose intolerance/type 2 diabetes, dyslipidemia, cardiovascular complications and liver dysfunction). Most of the clinical traits of TS are due to the haploinsufficiency of various genes on the X chromosome, particularly those in the pseudoautosomal regions (PAR 1 and PAR 2), which normally escape the physiological process of X inactivation, although other regions may also be implicated. The management of patients with TS requires collaboration between several healthcare providers. The attending physician, in collaboration with the national care network, will ensure that the patient receives optimal care through regular follow-up and screening. The various elements of this PNDS are designed to provide such support.

Women With Turner Syndrome Are Both Estrogen and Androgen Deficient: The Impact of Hormone Replacement Therapy

CONTEXT

Women with Turner syndrome (TS) suffer from hypergonadotropic hypogonadism, causing a deficit in gonadal hormone secretion. As a consequence, these women are treated with estrogen from the age of 12 years, and later in combination with progesterone. However, androgens have been given less attention.

OBJECTIVE

To assess sex hormone levels in women with TS, both those treated and those nontreated with hormone replacement therapy (HRT), and investigate the impact of HRT on sex hormone levels.

METHODS

At Aarhus University Hospital, 99 women with TS were followed 3 times from August 2003 to February 2010. Seventeen were lost during follow-up. Control group 1 consisted of 68 healthy age-matched control women seen once during this period. Control group 2 consisted of 28 young, eumenorrheic women sampled 9 times throughout the same menstrual cycle. Serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17β-estradiol, estrone sulfate, DHEAS, testosterone, free androgen index, androstenedione, 17-OH progesterone, and sex hormone-binding globulin (SHBG) were analyzed.

RESULTS

All androgens, 17-OH progesterone, and sex hormone-binding globulin (SHBG) were 30% to 50% lower in TS compared with controls (P < 0.01). FSH, LH, and estrone sulfate were more than doubled in women with TS compared with controls (P < 0.02). Using principal component analysis, we describe a positive correlation between women with TS receiving HRT, elevated levels of SHBG, and decreased levels of androgens.

CONCLUSION

The sex hormone profile in TS reveals a picture of androgen deficiency, aggravated further by HRT. Conventional HRT does not normalize estradiol levels in TS.

Turner Syndrome

Turner syndrome (TS) affects approximately 1 out of every 1500–2500 live female births, with clinical features including short stature, premature ovarian failure, dysmorphic features and other endocrine, skeletal, cardiovascular, renal, gastrointestinal and neurodevelopmental organ system involvement. TS, a common genetic syndrome, is caused by sex chromosome aneuploidy, mosaicism or abnormalities with complete or partial loss of function of the second X chromosome. Advances in genetic and genomic testing have further elucidated other possible mechanisms that contribute to pathogenic variability in phenotypic expression that are not necessarily explained by monosomy or haploinsufficiency of the X chromosome alone. The role of epigenetics in variations of gene expression and how this knowledge can contribute to more individualized therapy is currently being explored. TS is established as a multisystemic condition, with several endocrine manifestations of TS affecting growth, puberty and fertility having significant impact on quality of life. Treatment guidelines are in place for the management of these conditions; however, further data on optimal management is needed.

Fracture risk, underlying pathophysiology, and bone quality assessment in patients with Turner syndrome

Turner syndrome (TS), the most common type of X chromosomal disorder, has various, clinical manifestations. Among these, primary hypogonadism, which may lead to osteoporosis, is a life-long health issue. A high prevalence of fractures associated with osteoporosis is a major problem in patients with TS, where it may be 1.4-2.2 times higher than in healthy individuals and increases with age. Among the risk factors associated with fractures in TS, hypogonadism is arguably the most important. Estrogen deficiency due to hypogonadism leads to low bone mineral density (BMD), resulting in a high prevalence of bone fractures. Estrogen replacement therapy (ERT) in patients with TS reportedly improved their BMD. However, other causes of low BMD may exist, given that this condition begins in the prepubertal period in patients with TS. Most previous studies have reported low BMD in patients with TS using dual-energy X-ray absorptiometry (DXA), but this method has some limitations. Areal BMD values assessed by DXA were influenced by bone size and short stature, resulting in an underestimation of BMD. Currently, volumetric BMD values may be accurately obtained using peripheral quantitative computed tomography (pQCT). pQCT, high-resolution pQCT, and the trabecular bone score can also be used to evaluate bone quality, including bone geometry and microarchitecture, in TS. The present review discusses the high fracture risk, role of estrogen deficiency in low BMD, advantages and disadvantages of various bone assessment methods, and characteristics of bone quality in TS.

Position statement on the diagnosis and management of premature/primary ovarian insufficiency (except Turner Syndrome)

Premature ovarian insufficiency (POI) is a rare pathology affecting 1-2% of under-40 year-old women, 1 in 1000 under-30 year-olds and 1 in 10,000 under-20 year-olds. There are multiple etiologies, which can be classified as primary (chromosomal, genetic, auto-immune) and secondary or iatrogenic (surgical, or secondary to chemotherapy and/or radiotherapy). Despite important progress in genetics, more than 60% of cases of primary POI still have no identifiable etiology; these cases are known as idiopathic POI. POI is defined by the association of 1 clinical and 1 biological criterion: primary or secondary amenorrhea or spaniomenorrhea of>4 months with onset before 40 year of age, and elevated follicle-stimulating hormone (FSH)>25IU/L on 2 assays at>4 weeks' interval. Estradiol level is low, and anti-Müllerian hormone (AMH) levels have usually collapsed. Initial etiological work-up comprises auto-immune assessment, karyotype, FMR1 premutation screening and gene-panel study. If all of these are normal, the patient and parents may be offered genome-wide analysis under the "France Génomique" project. The term ovarian insufficiency suggests that the dysfunction is not necessarily definitive. In some cases, ovarian function may fluctuate, and spontaneous pregnancy is possible in around 6% of cases. In confirmed POI, hormone replacement therapy is to be recommended at least up to the physiological menopause age of 51 years. Management in a rare diseases center may be proposed.

Hypogonadism in male and female: which is the best treatment?

BACKGROUND

Subjects with hypo-or hypergonadotropic hypogonadism need hormone replacement therapy (HRT) to initiate puberty and maintain it with a normal hormonal status. While general recommendations for the management of HRT in adults have been published, no systematic suggestions focused on adolescents and young adults. The focus of this review is the HRT in males and females with hypogonadism, from puberty to late reproductive age, covering the different management options, encompassing sex steroid or gonadotropin therapy, with discussion of benefits, limitations and specific considerations of the different treatments.

METHODS

We conducted an extensive search in the 3 major scientific databases (PubMed, EMBASE and Google Scholar) using the keywords "hormonal replacement therapy", "hypogonadism", "bone mineral density", "estradiol/testosterone", "puberty induction", "delayed puberty". Case-control studies, case series, reviews and meta-analysis published in English from 1990 to date were included.

RESULTS

By considering the available opportunities for fertility induction and preservation, we hereby present the proposals of practical schemes to induce puberty, and a decisional algorithm to approach HRT in post-pubertal adolescents.

CONCLUSIONS

A condition of hypogonadism can underlie different etiologies involving the hypothalamic-pituitary-gonadal axis at different levels. Since the long-terms effects of hypogonadism may vary and include not only physical outcomes related to sex hormone deficiencies, but also psychological problems and implications on fertility, the initiation, maintenance and consolidation of puberty with different pharmaceutical options is of utmost importance and beside pubertal development, optimal uterine and testicular growth and adequate bone health should consider also the psychosocial wellbeing and the potential fertility.

Starting age of oestrogen-progestin therapy is negatively associated with bone mineral density in young adults with Turner syndrome independent of age and body mass index

OBJECTIVE

Osteoporosis is an important health issue in patients with Turner syndrome (TS), and oestrogen sufficiency has been implicated in increased bone mineral density (BMD); however, the impact of the starting age of hormone replacement therapy (HRT) on bone mineral density remains unclear, particularly during young adulthood.

DESIGN

A retrospective study from three tertiary care hospitals in Japan.

PATIENTS

One hundred and three patients with TS aged between 18 and 30 years of age who underwent dual-energy X-ray absorptiometry.

MEASUREMENTS

Anthropometric parameters, lumbar bone mineral density (L-BMD), including areal BMD (aBMD) and volumetric BMD (vBMD), karyotypes, the presence of spontaneous menarche, the starting ages of oestrogen replacement therapy (ERT) and oestrogen-progestin therapy (EPT), and the duration between starting ages of oestrogen replacement therapy and oestrogen-progestin therapy were investigated. vBMD was calculated based on the Kröger method.

RESULTS

aBMD was lower in young adults with TS than in an age-matched reference population. L-BMD positively correlated with weight and body mass index (BMI). L-BMD was higher in subjects with spontaneous menarche (N = 22) than in those without. A dose escalation regimen of oestrogen replacement therapy was used in 84% of subjects without spontaneous menarche (N = 81). The starting age of oestrogen replacement therapy and the duration between the starting ages of oestrogen replacement therapy and oestrogen-progestin therapy negatively and independently correlated with aBMD, but not with vBMD, after adjustment with age and BMI. The starting age of oestrogen-progestin therapy negatively correlated with L-BMD independent of age and BMI.

CONCLUSIONS

Early introduction of hormone replacement therapy, particularly oestrogen-progestin therapy, is important to accrue better L-BMD in young adults with TS.

Effects of age at estrogen replacement therapy initiation on trabecular bone score in Japanese adults with Turner syndrome

The effects of the age at estrogen replacement therapy (ERT) initiation on bone quality in Turner syndrome were evaluated using trabecular bone score. Early puberty ERT positively correlated with increase in bone quality. Early initiation of ERT is necessary for the acquisition of bone quality as well as bone density.

INTRODUCTION

Studies have reported associations between bone mineral density and estrogen replacement therapy (ERT) in Turner syndrome (TS) patients; however, few studies exist on the effect on bone quality. The aim of this study was to evaluate the effects of the age at ERT initiation on bone quality of Japanese TS patients, cross-sectionally and longitudinally.

METHODS

Cross-sectionally, 95 TS patients were divided into three groups based on their age at initiation of ERT: A (12-14 years, 11 patients), B (15-17 years, 47 patients), and C (over 18 years, 37 patients). To assess bone quality, trabecular bone score (TBS) was used. The effects of age at initiation and duration of ERT on TBS were examined using multiple regression analysis. In the longitudinal study, 48 patients who underwent dual-energy X-ray absorptiometry multiple times were divided into three groups: D (12-14 years, 8 patients), E (15-17 years, 18 patients), and F (over 18 years, 22 patients). Each group was analyzed for the rate of change in TBS per year.

RESULTS

Cross-sectionally, the TBS showed significant differences among the three groups (TBS A, 1.302; B, 1.299; C, 1.245) (p = 0.013); group C was significantly lower than B (p = 0.014); bone quality was degraded. Multiple regression analysis revealed that age at ERT initiation significantly affected the increase in TBS (p = 0.002). Longitudinally, the rate of change of TBS was not significantly different in the three groups (p = 0.73).

CONCLUSION

Early initiation of ERT may have positive effects on bone quality in TS. Large prospective studies will be needed.

Monitoring and maintaining bone health in patients with Turner syndrome

INTRODUCTION

Subjects affected with Turner Syndrome (TS) suffer low bone mineral density and high risk of fracture from a young age. Estrogen deficiency is considered the main risk factor but other factors, such as intrinsic bone abnormalities, enhanced osteoclastogenesis, vitamin D deficiency and other comorbidities may contribute to the exalted bone fragility.

AREAS COVERED

The authors performed a literature search in PubMed and EMBASE, using selected key words. They focused their search on pathogenetic mechanisms of osteoporosis in TS and updated the diagnosis, prevention and therapeutic interventions.

EXPERT OPINION

Bone health is a concern in subjects with TS, and strategies to prevent osteoporosis and fractures should be considered from childhood. Advice on how to live a healthy lifestyle, including physical activity and correct nutrition, should be given during childhood in order to prevent bone impairment later in life. The screening for vitamin D deficiency should be performed between the ages of 9 and 11, and every 2-3 years thereafter. Early initiation of estrogen replacement therapy (ERT) between 11-12 years of age, prompt titration to the adult dose after 2 years, and long-term follow-up to guarantee compliance with ERT, are the key points of osteoporosis prevention in women with TS.

A retrospective multicenter study of bone mineral density in adolescents and adults with Turner syndrome in Japan

Osteoporosis is one of the clinical features of women with Turner syndrome (TS). The reasons for low bone mineral density (BMD) and increased bone fragility are multifactorial, including estrogen deficiency, X-chromosome abnormalities, and environmental factors. Few, large-scale studies on bone mineral density in either adolescents or adults with TS have been done in Japan. The goal of the present study was to investigate spinal BMD in women with TS, assess its relationship with clinical parameters, especially estrogen replacement therapy, and investigate its longitudinal changes. The spinal BMD and clinical data of 149 Japanese women with TS aged 15 to 49 years who were followed at the four participating hospitals were retrospectively analyzed. The BMD Z-scores of the women with TS ranged from -5.30 to +1.89. Women with TS aged 15-39 years had lower BMD than healthy Japanese women (p < 0.01) while women with spontaneous menstruation had a significantly higher BMD Z-score than those without spontaneous menstruation (-0.73 ± 1.11 vs. -1.67 ± 1.18, p < 0.01). In women without spontaneous menstruation, BMD Z-scores correlated with the duration of their estrogen therapy (r = 0.167, p < 0.01). Women aged 15-39 years with TS had low BMD, which was associated with primary amenorrhea and short estrogen replacement therapy duration.

Ultra-low-dose estrogen therapy for female hypogonadism

In females, endogenous estrogen secretion increases gradually before pubertal development. The benefits of low-dose estrogen therapy in patients with Turner syndrome were originally discussed by Ross et al. and Quigley et al. These seminal studies used ethinyl estradiol (EE2), starting at a dose of 25 ng/kg/d. We hypothesized that the initial dosage of estrogen could be titrated to more closely mimic physiological increments of endogenous estrogen. Therefore, our recent study initiated EE2 treatment at a dosage of 1–2 ng/kg/d, an ultra-low-dose estrogen therapy in pediatric patients with Turner syndrome. The ultra-low-dose estrogen therapy in this syndrome produced a good final height outcome but achieved suboptimal bone mineral density (BMD). In the present review, we have explained our findings to clarify the merits and demerits of this new therapy and to promote further discussion and research. This type of ultra-low-dose estrogen therapy, initiated at an early age, could be ideal for estrogen replacement in female patients with hypogonadism, such as Turner syndrome.

Fracture rate in women with oestrogen deficiency - Comparison of Turner syndrome and premature ovarian insufficiency

OBJECTIVE

Women with early-onset oestrogen deficiency are at risk of reduced bone mineral density (BMD). We sought to assess fracture history and BMD in women with Turner syndrome (TS) and premature ovarian insufficiency (POI).

DESIGN

A cross-sectional observational study.

PATIENTS

Two hundred and sixty seven women with TS (median age 34.3 years) and 67 women with POI (median age 28.1 years).

MEASUREMENTS

A questionnaire was used to collect data on fracture history, co-morbidities and drug history including age at first oestrogen exposure. Clinical data included height, weight, serum vitamin D and hip and spine T-scores, which were adjusted for height and age. Fractures were subdivided into major osteoporotic fractures (MOF) and 'other' fracture types.

RESULTS

Overall fracture rate was similar in women with TS and POI (82 [30.5%] vs 22 [32.8%] respectively, P = .74). Compared to women with POI, those with TS had more fractures at MOF sites (30.2% vs 52.7%, P = .012) and fewer phalangeal fractures (27.9% vs 9.8%, P = .005). There was no difference in BMD between women who sustained a fracture compared to those who did not. Women with TS who fractured were more likely to suffer from hearing impairment compared to those with no fracture (62.2% vs 48.1%, P = .045).

CONCLUSIONS

TS is not associated with an overall excess risk of bone fracture. The higher rate of fractures at MOF sites in women with TS may be secondary to hearing impairment, thin cortical bone and abnormal bone remodelling.

Effects of the Timing of Sex-Steroid Exposure in Adolescence on Adult Health Outcomes

CONTEXT

Variation in pubertal timing is associated with a wide range of adult risks and outcomes, but it is unclear whether these associations are causal, and it is largely unknown whether these associations can be modified by treatment.

EVIDENCE ACQUISITION

We conducted PubMed searches to identify Mendelian randomization (MR) studies on the influence of pubertal timing on adult health and studies on sex-steroid treatment of the following conditions associated with reduced reproductive endocrine function in adolescence: constitutional delay, Turner syndrome, and Klinefelter syndrome.

EVIDENCE SYNTHESIS

Results of MR studies suggest that earlier pubertal timing increases body mass index; increases risk for breast, ovarian, endometrial, and prostate cancers; elevates fasting glucose levels and blood pressure; impairs lung capacity and increases risk for asthma; leads to earlier sexual intercourse and first birth; decreases time spent in education; and increases depressive symptoms in adolescence. Later pubertal timing appears to lower bone mineral density (BMD). Although studies of constitutional delay have not shown that sex-steroid treatment alters adult height or BMD, studies of girls with Turner syndrome and boys with Klinefelter syndrome suggest that earlier initiation of sex-steroid treatment improves physical and neurocognitive outcomes.

CONCLUSIONS

Despite having some limitations, MR studies suggest that pubertal timing causally influences many adult conditions and disease risks. Studies of Turner syndrome and Klinefelter syndrome suggest that earlier sex-steroid exposure may have short- and long-term benefits. The mechanisms underlying these findings and the effects of trends and treatments affecting pubertal timing remain to be determined.

Turner syndrome and osteoporosis

Turner syndrome is one of the most common sex chromosomal anomalies, characterized by the complete or partial loss of one X chromosome. Females with Turner syndrome are characterized by skeletal abnormalities, short stature and primary ovarian insufficiency. The aim of this narrative review was to identify the underlying mechanisms of osteoporosis in Turner syndrome, summarize its clinical manifestations and provide suggestions regarding the management of osteoporosis. Girls and women with Turner syndrome have lower bone mineral density and a higher fracture rate than healthy individuals. The most important risk factors for osteoporosis are inadequately treated primary ovarian insufficiency, followed by intrinsic bone abnormalities. Comorbidities that further increase the risk of osteoporosis include vitamin D deficiency, celiac disease and inflammatory bowel disease. In addition, hearing problems can predispose to falls. Early initiation of hormone replacement therapy (HRT) at the age of 11-13 years, prompt titration to the adult dose after 2 years and long-term follow-up to ensure compliance with HRT are the cornerstones of osteoporosis prevention in women with Turner syndrome.