Overnight urine growth hormone, cortisol and adenosine 3' 5' cyclic monophosphate excretion in children with chronic asthma treated with inhaled beclomethasone dipropionate

Long-term outcomes in paediatric asthma

Over the years the aims of asthma management have changed markedly from effective prednisolone treatment of symptoms and exacerbations towards more use of continuous prophylactic treatment. With our new understanding of the disease and its management definition of the aims of treatment and assessment of optimal asthma control have become much more complex. Even in times of evidence-based medicine our asthma management is based upon findings of effects on various outcomes in somewhat short-term (<1 year) controlled studies. However, assumptions about long-term effects upon the basis of findings in such studies should be made with great caution. Good examples of this are studies which assess the risk of systemic effects and clinical adverse effects of inhaled corticosteroids. From such studies it has become clear that systemic effects detected in short-term trials may have no predictive value of long-term adverse effects. Thus steroid-induced changes in lower leg growth rates assessed by knemometry do not predict long-term statural growth. Moreover, steroid-induced changes in statural growth over 1 year are not predictive of effects upon attained adult height. In contrast, reduced growth caused by uncontrolled asthma disease also seems to affect attained adult height adversely. These findings suggest that long-term outcomes should play a larger role when future asthma management strategies are decided. Some important long-term outcomes of asthma management in children include cure or remission of the disease, prevention of complications of the disease (airway remodelling, adverse effects upon growth/adult height, peak bone mineral density, physical impairment and psychosocial development) or its pharmacological management (adverse effects upon adult height, peak bone mineral density). More controlled long-term studies (several years) are needed to provide a better understanding of how these outcomes are best achieved.

Measures of hypothalamic-pituitary-adrenal function in patients with asthma treated with inhaled glucocorticoids: clinical and research implications

In asthmatic patients treated with inhaled glucocorticoids there may be a risk of suppression of hypothalamic-pituitary-adrenal (HPA) function. The aim of the present study was to review peer-refereed data on HPA function in asthmatic patients taking inhaled glucocorticoids, and to discuss the value of HPA function measures in clinical practice and research. There is no evidence that inhaled glucocorticoids in recommended doses cause clinically significant HPA insufficiency. If sensitive measures of basal adrenal activity are used, however, dose-related suppressive effects with specific drugs and application systems can be detected. In adults, fluticasone propionate appears to be more potent than budesonide or triamcinolone acetonide in suppressing measures of basal adrenal activity. Measures of basal adrenal activity are useful in clinical trials that assess and compare systemic activity of specific drugs, application devices, and administration regimens, but have no place in the management of asthma.

Effects of inhaled corticosteroids and inhaled cromolyn sodium on urinary growth hormone excretion in asthmatic children

Over the past few years there has been an increasing awareness that asthma is a chronic inflammatory airways disease. The current therapeutic strategies for treating asthma focus on suppressing the inflammatory process by using cromones or inhaled corticosteroids (ICS). The beneficial effects of ICS in asthma are now well known, but its detrimental effect on linear growth remains a controversial issue. The aim of this open label, nonrandomized, cross-sectional, one-time study was to determine the influence of these drugs on urinary growth hormone (U-GH) levels in prepubertal asthmatic children. U-GH levels were measured in 47 prepubertal asthmatic children who had been treated for at least 6 months with either ICS (beclomethasone or budesonide at a mean daily dose of 360 microg) or with 80 mg daily dose of cromolyn sodium (CrS). There were also nine healthy children who served as a control. These three groups of children were matched for age and gender ratio. The mean level of U-GH in the CrS-treated group was 2.94 +/- 0.96 ng/night; this was significantly higher compared to the mean level of the ICS-treated group (1.99 +/- 0.83 ng/night; P < 0.001) and to the mean level of the control group (1.98 +/- 0.39 ng/night; P < 0.006). There was no significant difference between the mean level of U-GH in the group treated by ICS and the controls (P < 0.9). These results show that the mean levels of U-GH secretion of the children who were treated by CrS for 6 months was significantly increased, compared to the mean U-GH level of the ICS-treated group and the controls. The mean U-GH levels in the last two groups showed no statistically significant difference.

Serum leptin and IGF-I levels in cystic fibrosis

The role of leptin in states of negative energy balance such as cystic fibrosis (CF) has not been explored. We hypothesized that leptin levels in patients with CF would be low due to correlation with body weight. Despite the importance of IGF-I in normal growth and anabolism, there are few data on IGF-I in CF. We studied 27 CF patients (25+/-5 yrs, 57+/-9 kg, 10M/17F) and 12 control subjects (25+/-4 yrs, 57+/-9 kg, 6M/6F). Each subject underwent analysis of lean body mass (LBM) and percent body fat by dual-energy x-ray absorptiometry (DEXA). Serum leptin and IGF-I levels were measured by radioimmunoassay. Serum leptin levels were similar both in CF and in controls (CF=5.3+/-4.1 ng/ml, C=4.4+/-3.6ng/ml; p=0.3), and there was no difference in percent body fat between the two groups (CF=26+/-13%, C=21+/-7%; p=0.3). Leptin levels were significantly lower in CF males than females corresponding to lower fat levels in males in both CF and controls. Leptin levels were positively correlated with percent body fat both in CF and controls (CF: r=0.8; p=0.01, CONTROL: r=0.8; p =0.2). Serum IGF-I levels were significantly lower in CF patients than in controls (CF=1.13+/-0.41 ng/ml, C=6.72+/-3.62 ng/ml; p=<0.01). We conclude that the physiological regulation of leptin is maintained in relation to body fat even in chronic illness and that the negative energy balance in CF is not caused by high leptin levels.

Proteolysis associated with insulin resistance in cystic fibrosis

OBJECTIVE

We hypothesized that patients with cystic fibrosis (CF) have higher rates of protein breakdown than normal volunteers and that the infusion of insulin would result in less suppression of proteolysis. Methods. Using [1-C]leucine and a three-step hyperinsulinemic euglycemic clamp, we measured rates of leucine appearance in 29 adult CF patients and 18 matched-control volunteers. The CF patients were characterized by oral glucose tolerance testing and clinical status scoring.

RESULTS

The CF patients had significantly increased proteolysis when compared with that of controls (CF, 123 +/- 28 micromol/kg/h; controls, 71 +/- 15 micromol/kg/h) and rates of proteolysis were significantly different between CF patients with impaired glucose tolerance and diabetes and those CF patients with normal glucose tolerance. Suppression of proteolysis by insulin was less in all CF subgroups than in the controls at peripheral insulin levels of 16 and 29 microU/mL. At peripheral insulin levels of 100 microU/mL, there was no difference in insulin suppression of proteolysis between CF patients and controls. Importantly, basal rates of proteolysis had an inverse relationship with clinical status in CF patients (r = -.76).

CONCLUSIONS

Our findings indicate that proteolysis is higher in adult CF patients than in controls and that CF patients exhibit resistance to the anabolic effects of insulin on proteolysis. Most significantly, our findings indicate that basal rates of proteolysis inversely correlate with clinical status in CF.

Asthma and growth--cause for concern? Asthma & Growth in Tayside Children

This project aimed to investigate the height and weight of children with asthma in the community. The Tayside Childhood Asthma Project examined medical records of 3143 children drawn from 12 general practices, for details of asthma morbidity and management. Concurrently, but independent from it, the Tayside Growth Study measured heights and weights of children aged 3-5, 5, 7, 9, 11 and 14 years. This paper reports on a cross-sectional analysis of 699 children who were known to be receiving some form of asthma medication during the school years 1990-91 and 1991-92 when a growth measurement was recorded. A standard deviation score (SDS) was calculated from height measurements for this cohort of children and from weight and body mass index (BMI = weight/height2) measurements for 559 of these children. The mean and standard deviation of these SDS values were calculated, and the distribution of the scores plotted. The results showed no difference in height, weight or BMI between the general population and the cohort receiving asthma medication. However, further analysis showed the distribution of height for children with severe asthma receiving high doses of inhaled corticosteroids (mean -0.38, SD 0.95) was significantly different from the general population (mean 0, SD 1). This group of children appeared to be shorter, by as much as 2 cm on average for a 5-year-old boy. In general, children receiving treatment for asthma within the community have a similar distribution of height and weight to normal children. Children receiving high-dose inhaled corticosteroids are shorter than their contemporaries, and deserve long-term follow-up.