Serum dehydroepiandrosterone sulfate concentration as an indicator of adrenocortical suppression in asthmatic children treated with inhaled steroids

Pharmacometabolomics of Asthma as a Road Map to Precision Medicine

Pharmacometabolomics applies the principles of metabolomics to therapeutics in order to elucidate the biological mechanisms underlying the variation in responses to drugs between groups and individuals. Asthma is associated with broad systemic effects and heterogeneity in treatment response and as such is ideally suited to pharmacometabolomics. In this chapter, we discuss the state of the emerging field of asthma pharmacometabolomics, with a particular focus on studies of steroids, bronchodilators, and leukotriene inhibitors. We also consider those studies concerned with subtyping cases to better understand the pharmacology of those groups and those looking to leverage pharmacometabolomics for asthma prevention. We finish with a discussion of the challenges and opportunities of asthma pharmacometabolomics and reflect upon where this field must go next in order to realize its precision medicine potential.

Possible genetical predictors of efficacy and safety of budesonide-MMX in patients with mild-to-moderate ulcerative colitis, and safety comparison with methylprednisolone

BACKGROUND

Budesonide-MMX is a topically active corticosteroid degraded by cytochrome-P450 enzymes, resulting in favorable side-effect profile. We aimed to assess the effect of CYP genotypes on safety and efficacy, and make a direct comparison with systemic corticosteroids.

RESEARCH DESIGN AND METHODS

We enrolled UC patients receiving budesonide-MMX and IBD patients on methylprednisolone in our prospective, observational-cohort study. Before and after treatment regimen clinical activity indexes, laboratory parameters (electrolytes, CRP, cholesterol, triglyceride, dehydroepiandrosterone, cortisol, beta-crosslaps, osteocalcin), and body composition measurements were assessed. CYP3A4 and CYP3A5 genotypes were determined in the budesonide-MMX group.

RESULTS

71 participants were enrolled (budesonide-MMX: 52; methylprednisolone: 19). CAI decreased (p<0.05) in both groups. Cortisol decreased (p<0.001), and the level of cholesterol was elevated in both groups (p<0.001). Body composition altered only following methylprednisolone. Bone homeostasis (osteocalcin; p<0.05) and DHEA (p<0.001) changed more prominently after methylprednisolone. Glucocorticoid-related adverse events were more common following methylprednisolone treatment (47.4% compared to 1.9%). CYP3A5(*1/*3) genotype positively influenced efficacy, but not safety. Only one patient's CYP3A4 genotype differed.

CONCLUSIONS

CYP genotypes can affect the efficacy of budesonide-MMX; however, further studies would be needed with analyses of gene expression. Although budesonide-MMX is safer than methylprednisolone, due to glucocorticoid-related side effects, admission should require greater precaution.

Glucocorticoid induced adrenal insufficiency

Synthetic glucocorticoids are widely used for their anti-inflammatory and immunosuppressive actions. A possible unwanted effect of glucocorticoid treatment is suppression of the hypothalamic-pituitary-adrenal axis, which can lead to adrenal insufficiency. Factors affecting the risk of glucocorticoid induced adrenal insufficiency (GI-AI) include the duration of glucocorticoid therapy, mode of administration, glucocorticoid dose and potency, concomitant drugs that interfere with glucocorticoid metabolism, and individual susceptibility. Patients with exogenous glucocorticoid use may develop features of Cushing's syndrome and, subsequently, glucocorticoid withdrawal syndrome when the treatment is tapered down. Symptoms of glucocorticoid withdrawal can overlap with those of the underlying disorder, as well as of GI-AI. A careful approach to the glucocorticoid taper and appropriate patient counseling are needed to assure a successful taper. Glucocorticoid therapy should not be completely stopped until recovery of adrenal function is achieved. In this review, we discuss the factors affecting the risk of GI-AI, propose a regimen for the glucocorticoid taper, and make suggestions for assessment of adrenal function recovery. We also describe current gaps in the management of patients with GI-AI and make suggestions for an approach to the glucocorticoid withdrawal syndrome, chronic management of glucocorticoid therapy, and education on GI-AI for patients and providers.

Adrenal function in cystic fibrosis

Cystic fibrosis (CF) is not known to directly affect the adrenal gland, but commonly used CF therapies do impact the function of the hypothalamic-pituitary-adrenal (HPA) axis. By binding to the glucocorticoid receptor, medications such as inhaled and oral corticosteroids can enhance the systemic effects of cortisol and result in iatrogenic Cushing syndrome. Prolonged use suppresses the body's ability to make cortisol, resulting in iatrogenic adrenal insufficiency upon medication discontinuation. Chronic use of inhaled and oral corticosteroids can negatively affect bone health, growth, and glucose metabolism. This chapter provides practical guidelines regarding the screening, diagnosis, and treatment of iatrogenic adrenal insufficiency. As the guidelines are mainly derived from the asthma literature, this chapter also highlights the need for studies to evaluate the impact of CF therapies on adrenal function and other CF-endocrinopathies.

Efficacy and safety of inhaled corticosteroids relative to fluticasone propionate: a systematic review of randomized controlled trials in asthma

INTRODUCTION

Many trials have been published comparing inhaled corticosteroid (ICS) treatments in asthma. However, mixed results necessitate the summarization of available evidence to aid in decision-making. Areas covered: This systematic review evaluated randomized controlled trials (RCTs) that compared the efficacy and safety of inhaled fluticasone propionate (FP) with other ICS including beclomethasone dipropionate (BDP), budesonide (BUD) and ciclesonide (CIC). PubMed was searched and 54 RCTs that fit pre-determined criteria were included. Endpoints evaluated included lung function, asthma symptom control, exacerbation frequency, reliever use, quality of life and steroid-related side effects. Expert commentary: Across all studies, FP was associated with either more favorable or at least similar efficacy and safety, in comparison with BDP or BUD. This observation may be related to FP's higher relative potency and almost negligible oral bioavailability. FP was comparable to CIC for efficacy. However, CIC appeared to have a smaller impact on cortisol levels than FP, which is likely due to CIC's incomplete conversion to active metabolite (des-CIC) and the lower potency of des-CIC compared with FP. Although there were no significant differences in evaluated outcomes after treatment with different ICS in the majority of studies, some observed differences could be explained by their respective pharmacodynamic and pharmacokinetic properties.

Premature adrenarche: etiology, clinical findings, and consequences

Adrenarche means the morphological and functional change of the adrenal cortex leading to increasing production of adrenal androgen precursors (AAPs) in mid childhood, typically at around 5-8 years of age in humans. The AAPs dehydroepiandrosterone (DHEA) and its sulfate conjugate (DHEAS) are the best serum markers of adrenal androgen (AA) secretion and adrenarche. Normal ACTH secretion and action are needed for adrenarche, but additional inherent and exogenous factors regulate AA secretion. Inter-individual variation in the timing of adrenarche and serum concentrations of DHEA(S) in adolescence and adulthood are remarkable. Premature adrenarche (PA) is defined as the appearance of clinical signs of androgen action (pubic/axillary hair, adult type body odor, oily skin or hair, comedones, acne, accelerated statural growth) before the age of 8 years in girls or 9 years in boys associated with AAP concentrations high for the prepubertal chronological age. To accept the diagnosis of PA, central puberty, adrenocortical and gonadal sex hormone secreting tumors, congenital adrenal hyperplasia, and exogenous source of androgens need to be excluded. The individually variable peripheral conversion of circulating AAPs to biologically more active androgens (testosterone, dihydrotestosterone) and the androgen receptor activity in the target tissues are as important as the circulating AAP concentrations as determinants of androgen action. PA has gained much attention during the last decades, as it has been associated with small birth size, the metabolic and polycystic ovarian syndrome (PCOS), and thus with an increased risk for type 2 diabetes and cardiovascular diseases in later life. The aim of this review is to describe the known hormonal changes and their possible regulators in on-time and premature adrenarche, and the clinical features and possible later health problems associating with PA.

Screening for hypothalamic-pituitary-adrenal axis suppression in asthmatic children remains problematic: a cross-sectional study

OBJECTIVE

To determine which parameter is the most useful screening test for hypothalamic-pituitary-adrenal suppression in asthmatic children.

DESIGN

Cross-sectional study.

SETTING

Paediatric allergy clinics in Cape Town, South Africa.

PARTICIPANTS

143 asthmatic children of mostly mixed ancestry, aged 5-12 years.

OUTCOME MEASURES

Primary outcome measures included Spearman correlation coefficients (r) calculated between the postmetyrapone (PMTP) serum adrenocorticotropic hormone (ACTH), 11-deoxycortisol (11DOC), 11DOC+ cortisol (C) and height, weight, height velocity, weight velocity, change in systolic blood pressure from supine to standing, early morning urinary free cortisol (UFC), morning C, ACTH and dehydroepiandrosterone sulfate (DHEAS). Secondary outcome measures were the receiver operating characteristics (ROC) curve and the diagnostic statistics for the most promising test.

RESULTS

All screening variables were weakly correlated with the three PMTP outcomes. Only DHEAS and UFC (nmol/m(2)) were statistically significant-DHEAS for PMTP ACTH and 11DOC (r=0.20, p=0.025 and r=0.21, p=0.017); UFC (nmol/m(2)) for PMTP 11DOC and 11DOC+C (r=0.19, p=0.033 and r=0.20, p=0.022). The area under ROC curve for DHEAS in the 5-year to 9-year age group was 0.69 (95% CI 0.47 to 0.92). At DHEAS cut-off of 0.2 µmol/L: sensitivity=0.88 (CI 0.47 to 1.00), specificity=0.61 (CI 0.42 to 0.78), positive predictive value=0.37 (CI 0.16 to 0.62), negative predictive value=0.95 (CI 0.75 to 1.00), accuracy=0.67 (CI 0.50 to 0.81), positive likelihood ratio=2.26 (CI 1.35 to 3.78), negative likelihood ratio=0.20 (CI 0.03 to 1.30).

CONCLUSIONS

No parameter is useful as a universal screening test. DHEAS may be suitable to exclude HPAS before adrenarche. Further research is needed to confirm these findings and identify factors, for example, genetic that may predict or protect against HPAS.

Respostas fisiológicas em adolescentes obesos submetidos à broncoprovocação com solução salina hipertônica

INTRODUÇÃO: A hiper-responsividade brônquica é a resposta do aumento dos mecanismos fisiológicos protetores das vias aéreas em indivíduos atópicos e não atópicos. Além disso, a magnitude da hiperresponsividade aérea apresenta influência conforme o grau de obesidade. OBJETIVO: Avaliar as respostas fisiológicas em adolescentes obesos submetidos a hiper-responsividade brônquica a solução salina hipertônica. MATERIAIS E MÉTODOS: Estudo descritivo, transversal e correlacional composto por 15 adolescentes obesos, de ambos os gêneros. O diagnóstico de asma foi realizado por meio de histórico clínico e questionário ISAAC, e a obesidade pelo IMC acima do percentil 95. Utilizou-se o teste de broncoprovocação por solução salina hipertônica para avaliação da hiper-responsividade brônquica, considerando positiva uma diminuição do volume expiratório forçado no primeiro segundo (VEF1) > 15% do valor pré-solução salina e a intensidade da hiper-responsividade brônquica foi calculada pela queda percentual máxima do VEF1 (% Queda máxVEF1). Foram utilizados o teste t independente ou U de Mann-Whitney e a correlação de Spearman rho (p < 0,05). RESULTADOS: Não foram encontradas diferenças significativas entre os asmáticos e não asmáticos para as variáveis antropométricas, espirométricas, lipídicas e hemodinâmicas. Verificaram-se moderadas correlações positivas e diferenças significativas entre o % Queda máxVEF1 com o IMC (p = 0,040) e IMC escore-Z (p = 0,028). Foram detectadas correlações negativas e diferenças significativas para a Queda máxVEF1 e leucócitos (p = 0,005) e para o % Queda máxVEF1 com o sulfato de dehidropiandrosterona (p = 0,032). CONCLUSÃO: Pode-se concluir que os adolescentes obesos submetidos a hiper-responsividade brônquica apresentam alterações espirométricas que estão associadas às inflamações sistêmicas da obesidade.

Asthma and dehydroepiandrosterone (DHEA): facts and hypotheses

Dehydroepiandrosterone (DHEA) is considered as an important immunomodulating and anti-inflammatory hormone. Despite the continuing interest in DHEA replacement therapy, our knowledge of its effects upon asthma is very limited. DHEA is able to reverse cytokine imbalances associated with asthma, may prevent and attenuate allergic inflammation in airways, and does not possess the undesirable side effects of glucocorticoids; therefore, it may be potentially applied in the treatment of asthma. The steroid-sparing effect observed with DHEA clinically could appear especially favorable in asthmatic patients receiving oral treatment and those inhaling high doses of glucocorticoids. In addition, DHEA and its analogs might prove useful in reversing relative glucocorticoids insensitivity in patients with corticosteroid-resistant asthma. In this review we have focused specifically on DHEA's role in asthma.

Gender-specific asthma treatment

Because genetic characteristics vary among subjects, the therapeutic effects of a certain drug differ among patients with the same disease. For this reason, special interest has focused on tailored treatments. Although it is well known that sex is genetically determined, little attention has been paid to sex differences in the clinical features and treatment of asthma. Females are more likely to suffer allergic asthma, to have difficulty controlling asthma symptoms, and to show adverse effects to drugs. As asthma symptoms show cyclic changes depending on female hormone levels in many women of child-bearing age, the use of contraceptives may specifically help to treat female patients with asthma such as those with perimenstrual asthma and severe asthma. Generally, testosterone seems to suppress asthma, and dehydroepiandrosterone (DHEA), a less virilizing androgen, may be effective for treating asthma. Evidence exists for a therapeutic and steroid-sparing effect of DHEA. However, further studies on the optimal dose and route of DHEA for each sex are needed. Monitoring of the serum DHEA-S level is necessary for patients with asthma on inhaled steroid treatment, and at minimum, replacement therapy for patients with a low level of DHEA may be helpful for treating their asthma.