The diagnosis of Cushing's syndrome (CS) is often a challenge. Recently, the determination of late night salivary cortisol levels has been reported to be a sensitive and convenient screening test for CS. However, no studies have included a comparison with other screening tests in a setting more closely resembling clinical practice, i.e. few patients with CS to be distinguished from patients with pseudo-Cushing states (PC), including the large population of obese patients. The aim of this study was to compare the diagnostic performance of midnight salivary cortisol (MSC) measurement with that of midnight serum cortisol (MNC) and urinary free cortisol (UFC) in differentiating 41 patients with CS from 33 with PC, 199 with simple obesity, and 27 healthy normal weight volunteers. Three patients with CS had MSC levels lower than the cut-off point derived from receiver operator characteristic analysis (9.7 nmol/liter), yielding a sensitivity for this parameter of 92.7%. In the whole study population, no statistically significant differences in terms of sensitivity, specificity, diagnostic accuracy, and predictive values were observed among tests. In particular, the overall diagnostic accuracy for MSC (93%; 95% confidence interval, 90.1-95.9%) was similar to those of UFC (95.3%; 94.1-96.5%) and MNC (95.7%; 93.4-98%; both P = NS). The diagnostic performance of MSC was superimposable to that of MNC also within the area of overlap in UFC values (< or =569 nmol/24 h) between CS and PC. In conclusion, MSC measurement can be recommended as a first-line test for CS in both low risk (simple obesity) and high-risk (i.e. PC) patients. Given its convenience, this procedure can be added to tests traditionally used for this purpose, such as UFC and MNC.

Objective: To compare salivary, plasma and urinary free cortisol (UFC) measurements in patients with anorexia nervosa, in whom an overdrive of the hypothalamic±pituitary±adrenal (HPA) axis is well established but information on salivary cortisol is lacking, in viscerally obese patients in whom subtle abnormalities of cortisol secretion and metabolism are postulated, and in normal-weight healthy women. Participants and experimental design: Measurement of salivary cortisol offers a convenient way to assess the concentrations of free, biologically active cortisol in plasma in different physiopathological settings. Forty-seven drug-free, newly diagnosed women with active restrictive anorexia nervosa, 30 restrictive anorexic women undergoing chronic psychopharmacological treatment, 47 women with mild-to-moderate visceral obesity, 103 women with severe central obesity and 63 normal-weight healthy women entered the study. Salivary and blood samples were collected at 0800 h, 1700 h and 2400 h, together with three consecutive 24-h urine specimens for UFC determination. In controls and patients with anorexia nervosa n 83Y salivary and plasma cortisol were also measured after a 1-mg overnight dexamethasone suppression test (DST). In patients with anorexia nervosa, mood was rated by the Hamilton scale for anxiety and depression. Results: Untreated patients with anorexia nervosa showed increased plasma and salivary cortisol and UFC concentrations (all P , 0X001 compared with controls), and decreased cortisol suppression after DST in plasma and saliva (P , 0X0001 and P , 0X005 respectively compared with controls). These alterations were less pronounced, although still statistically signi®cant, in treated patients with anorexia nervosa. Salivary cortisol was highly correlated with paired plasma cortisol in the whole population and after splitting the participants by group P , 0X0001X However, for plasma cortisol values greater than 500 nmol/l (the corticosteroid-binding globulin saturation point), this parallelism was lost. Taking plasma cortisol as a reference, the level of agreement for postdexamethasone salivary and plasma cortisol was 58.9% among suppressors and 77.8% among nonsuppressors (x 2 test: P , 0X01). Decreased 0800 h/2400 h cortisol ratios were observed in plasma and saliva in drug-free patients with anorexia nervosa (P , 0X005 and P , 0X05 respectively compared with controls), and in saliva in severely obese patients (P , 0X05 compared with controls). Depression and anxiety scores were unrelated to cortisol concentrations in any compartment. Conclusions: Salivary cortisol measurement is a valuable and convenient alternative to plasma cortisol measurement. It enables demonstration of the overdrive of the HPA axis in anorexia nervosa and subtle perturbations of the cortisol diurnal rhythm in women with visceral obesity. With the establishment of more speci®c and widely acceptable cut-off values for dynamic testing, measurement of salivary cortisol could largely replace plasma cortisol measurement.

Cushing's syndrome is associated with an increased risk for abnormalities of cardiac mass, which ameliorates, but does not fully disappear after remission. Systolic and diastolic functions are largely within the normal range in these patients.

Acromegalic patients frequently display an abnormally prolonged QT interval, a known risk factor for potentially fatal arrhythmias. Treatment of these patients with SSA is able to improve and even normalize this alteration, probably contributing to the beneficial effects of these drugs on cardiac rhythm in this endocrine disorder. The inclusion of octreotide in the list of drugs that may increase QTc should be reconsidered as regards its indication in acromegaly.