Nocturnal Dexamethasone versus Hydrocortisone for the Treatment of Children with Congenital Adrenal Hyperplasia

Current and Novel Treatment Strategies in Children with Congenital Adrenal Hyperplasia

BACKGROUND

The standard treatment for congenital adrenal hyperplasia (CAH) in children is still hydrocortisone. Improved strategies for timing of the dose during the day and the dose per square meter body surface area used in children of different ages and developmental phases have improved the situation and outcome for the patients. Neonatal screening enables an earlier diagnosis and initiation of treatment, prevents from adrenal crisis, and improves growth and development also for children with the less severe forms of CAH.

SUMMARY

This review describes the current treatment strategies for children with CAH and discusses some potential treatment options that have been developed with the primary aim to decrease the adrenal androgen production. Novel modified release glucocorticoid therapies are also discussed.

KEY MESSAGES

The long-term effects of the new adjunct therapies are unknown, and some are not suitable for use in children and adolescents. The effects of the new therapies on bone mineral density, gonadal functions, and long-term cognitive development are yet to be assessed. It is not known what levels of adrenal androgens are optimal for normal growth, puberty, and bone health. The basis of using glucocorticoids and mineralocorticoids in the treatment of CAH remains, and in some individuals, it may be beneficial to add therapies to reduce the androgen load during certain life stages.

Glucocorticoid Regimens in the Treatment of Congenital Adrenal Hyperplasia: A Systematic Review and Meta-Analysis

Management of congenital adrenal hyperplasia (CAH) requires both glucocorticoid replacement and suppression of adrenal androgen synthesis. It is recommended that children with CAH be treated with hydrocortisone, but the appropriate glucocorticoid regimen in adults is uncertain. In order to review the outcomes of different glucocorticoid regimens in the management of CAH, a systematic search of PubMed/MEDLINE and Web of Science was conducted, including reports published up to 25 February 2019. Studies that compared at least two types of glucocorticoid preparation were included. The following information was extracted from each study: first author, year of publication, number and characteristics of patients and control subjects, types and doses of glucocorticoid regimen used, study design and outcomes [e.g., biochemical tests, weight, height, body mass index (BMI), bone mineral density (BMD)]. A total of 23 studies were included in the qualitative synthesis, with 19 included in the quantitative synthesis. Dexamethasone was associated with the greatest degree of adrenal suppression; there was no significant difference in 17-hydroxyprogesterone (17OHP) and androstenedione levels between patients treated with hydrocortisone or prednisolone. Patients treated with dexamethasone had the lowest BMD and the highest BMI. Although dexamethasone therapy is associated with significantly lower 17OHP and androstenedione levels, it is also associated with more adverse effects. There do not appear to be significant differences between hydrocortisone and prednisolone therapy, and the choice of agent should be based on individual patient factors.

Novel insights into glucocorticoid replacement therapy for pediatric and adult adrenal insufficiency

Adrenal insufficiency is defined as impaired adrenocortical hormone synthesis. According to its source, the deficit is classified as primary (adrenal steroidogenesis impairment), secondary (pituitary adrenocorticotropic hormone deficit) or tertiary (hypothalamic corticotropin-releasing hormone deficit). The management of adrenal insufficiency resides primarily in physiological replacement of glucocorticoid secretion. Standard glucocorticoid therapy is shrouded in several controversies. Along the difficulties arising from the inability to accurately replicate the pulsatile circadian cortisol rhythm, come the uncertainties of dose adjustment and treatment monitoring (absence of reliable biomarkers). Furthermore, side effects of inadequate replacement significantly hinder the quality of life of patients. Therefore, transition to circadian hydrocortisone therapy gains prominence. Recent therapeutic advancements consist of oral hydrocortisone modified-release compounds (immediate, delayed and sustained absorption formulations) or continuous subcutaneous hydrocortisone infusion. In addition to illustrating the current knowledge on conventional glucocorticoid regimens, this review outlines the latest research outcomes. We also describe the management of pediatric patients and suggest a novel strategy for glucocorticoid replacement therapy in adults.

Differential effects of hydrocortisone, prednisone, and dexamethasone on hormonal and pharmacokinetic profiles: a pilot study in children with congenital adrenal hyperplasia

Background

Little is known about the comparative effects of different glucocorticoids on the adrenal and growth hormone (GH) axes in children with congenital adrenal hyperplasia (CAH). We sought to compare the effects of hydrocortisone (HC), prednisone (PDN), and dexamethasone (DEX) in children with classic CAH and to investigate a potential role of pharmacogenetics.

Methods

Subjects were randomly assigned to three sequential 6-week courses of HC, PDN, and DEX, each followed by evaluation of adrenal hormones, IGF-1, GH, and body mass index (BMI). Single nucleotide polymorphism (SNP) analysis of genes in the glucocorticoid pathway was also performed.

Results

Nine prepubertal subjects aged 8.1 ± 2.3 years completed the study. Mean ACTH, androstenedione, and 17-hydroxyprogesterone (17-OHP) values were lower following the DEX arm of the study than after subjects received HC (p ≤ 0.016) or PDN (p ≤ 0.002). 17-OHP was also lower after HC than PDN (p < 0.001). There was no difference in IGF-1, GH, or change in BMI. SNP analysis revealed significant associations between hormone concentrations, pharmacokinetic parameters, and variants in several glucocorticoid pathway genes (ABCB1, NR3C1, IP013, GLCCI1).

Conclusions

DEX resulted in marked adrenal suppression suggesting that its potency relative to hydrocortisone and prednisone was underestimated. SNPs conferred significant differences in responses between subjects. Although preliminary, these pilot data suggest that incorporating pharmacogenetics has the potential to eventually lead to targeted therapy in children with CAH.

Hormonal circadian rhythms in patients with congenital adrenal hyperplasia: identifying optimal monitoring times and novel disease biomarkers

OBJECTIVES

The treatment goal in congenital adrenal hyperplasia (CAH) is to replace glucocorticoids while avoiding androgen excess and iatrogenic Cushing's syndrome. However, there is no consensus on how to monitor disease control. Our main objectives were to evaluate hormonal circadian rhythms and use these profiles to identify optimal monitoring times and novel disease biomarkers in CAH adults on intermediate- and long-acting glucocorticoids.

DESIGN

This was an observational, cross-sectional study at the National Institutes of Health Clinical Center in 16 patients with classic CAH.

METHODS

Twenty-four-hour serum sampling for ACTH, 17-hydroxyprogesterone (17OHP), androstenedione (A4), androsterone, DHEA, testosterone, progesterone and 24-h urinary pdiol and 5β-pdiol was carried out. Bayesian spectral analysis and cosinor analysis were performed to detect circadian rhythmicity. The number of hours to minimal (TminAC) and maximal (TmaxAC) adrenocortical hormone levels after dose administration was calculated.

RESULTS

A significant rhythm was confirmed for ACTH (r(2), 0.95; P<0.001), 17OHP (r(2), 0.70; P=0.003), androstenedione (r(2), 0.47; P=0.043), androsterone (r(2), 0.80; P<0.001), testosterone (r(2), 0.47; P=0.042) and progesterone (r(2), 0.64; P=0.006). The mean (s.d.) TminAC and TmaxAC for 17OHP and A4 were: morning prednisone (4.3 (2.3) and 9.7 (3.5) h), evening prednisone (4.5 (2.0) and 10.3 (2.4) h), and daily dexamethasone (9.2 (3.5) and 16.4 (7.2) h). AUC0-24 h progesterone, androsterone and 24-h urine pdiol were significantly related to 17OHP.

CONCLUSION

In CAH patients, adrenal androgens exhibit circadian rhythms influenced by glucocorticoid replacement. Measurement of adrenocortical hormones and interpretation of results should take into account the type of glucocorticoid and time of dose administration. Progesterone and backdoor metabolites may provide alternative disease biomarkers.

Congenital adrenal hyperplasia--pharmacologic interventions from the prenatal phase to adulthood

Congenital adrenal hyperplasia (CAH) is one of the most common inherited autosomal recessive disorders, caused by deficiency of one of the enzymes involved in steroid synthesis. The clinical picture of the most prevalent form, i.e. 21-hydroxylase deficiency, is characterized by cortisol and mostly aldosterone deficiency and androgen excess (leading to congenital virilization in girls). Treatment consists of glucocorticoids, aimed at substitution of cortisol deficiency and, decrease of androgen excess. Usually supraphysiological doses of glucocorticoids are required to effectively suppress adrenal androgens. Furthermore, with the currently available glucocorticoid preparations, it is not possible to simulate a normal circadian rhythm in CAH patients. Therefore, it is a difficult task for (pediatric) endocrinologists to find the best balance between under- and overtreatment thereby avoiding important long term complications. In this review we will discuss the current pharmacologic treatment options. We give age dependent dose recommendations and describe the limitations of current treatment strategies. We discuss effects on fertility, bone density and cardiovascular risks. Recommendations about the use of glucocorticoids in case of fever or stress situations are given. The principles of treatment of non classic (mild) CAH are discussed in a separate section. Also prenatal therapy, to prevent congenital virilization of a female CAH newborn, is discussed. Furthermore, an overview of alternative pharmacological treatment options in the future is given.