Effect of concurrent medical illness on dexamethasone suppression test results in depressed inpatients

A retrospective evaluation of the clinical records of 138 depressed patients, who received the dexamethasone suppression test (DST) as part of a standardized physical and psychiatric assessment protocol, revealed that 60 had acute, chronic (mild or severe), stable or remitted medical conditions. The proportion of DST nonsuppressors did not differ between depressed subjects with medical conditions (45% nonsuppressors) and those without (34.6% nonsuppressors; p greater than 0.2). However, all of the six subjects with acute or chronic-severe medical conditions were found to be nonsuppressors (p = 0.003). These results may help clarify the medical exclusion criteria for the clinical application of the DST.