Cortisol cut-points for the glucagon stimulation test in the evaluation of hypothalamic pituitary adrenal axis.

Diagnosis of adrenal insufficiency requires evaluation by dynamic stimulation tests. The insulin tolerance test (ITT) is accepted as the gold-standard test for the evaluation of hypothalamo-pituitary-adrenal (HPA) axis but the test is unpleasant and dangerous. Although it takes more time, glucagon stimulation test (GST) is a good alternative to ITT. The primary aim of this study was to compare the ITT and GSTs in the evaluation of HPA axe in patients with pituitary disorders. We conducted a prospective study in which ITT and GST were performed within 7 days in 81 patients. Serum cortisol was measured. We divided our population in Group 1 (G1): Adrenal Insufficiency (Peak cortisol under ITT <200 ng/mL) and Group 2 (G2): normal response (Peak cortisol under ITT >200 ng/mL). Receiver-operating characteristic (ROC) analysis was performed to identify the thresholds for GST. The mean peak of cortisol under GST was not significantly different from that obtained after ITT in the whole cohort (182.67 ± 89.07 ng/mL vs. 179.75 ± 79.01 ng/mL), and it was significantly reduced in patients of G1 (p < 10-3). ROC curve analysis showed that the best diagnostic accuracy was obtained with a peak cortisol cut-off to GST of 167 ng/mL (sensitivity, 89%; specificity, 79%). Using this cut-off, 86.4% of the patients were correctly classified. In our prospective series, GST is a potential accurate and safe alternative test for the assessment HPA. Test-specific cut-offs should be applied to avoid misinterpretation.

Comparison of cigarette and waterpipe smoking among pupils in the urban area of Sousse, Tunisia.

BACKGROUND: Epidemiological and observational evidence suggests that waterpipe use is growing in popularity worldwide. AIM: The purpose of this study was to examine the prevalence of cigarette and water pipe tobacco use among pupils aged 13-17 years in the urban area of Sousse, Tunisia and to identify the factors which predict current cigarette and/or waterpipe smoking in this population. METHODS: Across-sectional study was carried out on a representative sample of schoolchildren aged between 13 and 17 years in colleges and public secondary schools of the urban area of Sousse. We used a pre tested and self administered questionnaire to measure tobacco consumption. The significance level for all analyses was p<0.05. Statistical analysis was conducted with SPSS 10.0 software. RESULTS: Participants were 1569 youth. Fifty two percent of them were male. The mean age of the sample was 15+/-1.5 years. Total cigarette smoking percentage for ever and current use were 33.1% and 7.6% respectively. Total water pipe smoking percentage for ever and current use were 19.3% and 5.2% respectively. Overall, the total percentages of cigarette and water pipe smoking (ever and current) were higher for male and aged pupils. Multivariate regression analyses showed that the two types of tobacco use were related. CONCLUSION: Despite the growing adoption of water-pipe smoking, there remains limited research in this area. Increased surveillance and additional research are necessary to address this growing threat to public health.