A clinical index for rating severity in Cushing's syndrome

Background: In assessing the clinical response to medical and/or surgical t reatments in patients with established Gushing's syndrome, the need for an instrument that could measure the magnitude of changes in the most common s ymptoms was felt, We therefore tested the usefulness of a simple clinical i ndex, the Gushing's syndrome severity index (GSI), based on clinimetric pri nciples. Eight clinical features were selected. Each one was graded on an o rdinal 3-point scale (0-2) with specification of anchor points based on sev erity. The total score ranged from 0 to 16, Methods: Interrater agreement, construct validity and concurrent validity of the index were evaluated. Fou rteen patients with Gushing's syndrome were evaluated independently by 2 en docrinologists before and after successful treatment. The GSI and two globa l scales of illness severity were administered. Urinary cortisol measuremen ts were also performed. Results: The intraclass correlation coefficient of the CS I was 0.95 before treatment and 0.87 after treatment. The GSI signif icantly discriminated (p < 0.001) the effects of treatment and paralleled t he changes in urinary cortisol. There were significant correlations between GSI and global scales of illness severity and change after treatment. Conc lusion: The results indicate that the GSI is a valid and reliable clinimetr ic method to evaluate severity in Gushing's syndrome. It may provide a tool for better assessing the complex array of signs and symptoms in this condi tion, The index is suitable for descriptive studies, outcome investigations and treatment trials. Copyright (C) 2000 S. Karger AG. Basel.