DST in depressed inpatient versus outpatient children

DexamethasoneSuppressionTest

DEXAMETHASONE

SUPPRESSION

BIOL PSYCHIATRY 1989;25:3lA-42A

37A

TEST

Thursday, May 4, 190 to 6:00 Hilton Ballroom B

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PLASMA DEXAMETHASONE LEVELS IN CHILDREN THE DEXAMETHASONE SUPPRESSION TEST Michael W. Naylor, John F. Greden, Norman E. Alessi

GIVEN

Ann Arbor, MI

To determine whether plasma dexamethasone levels affect post-dexamethasone plasma cortisol concentration, and subsequently dexamethasone suppression test (DST) suppressor status, we administered the DST to 73 patients ranging in age from 5-14 years. Plasma dexamethasone levels and post-dexamethasone cortisol levels were measured at 490 pm on day two. We found: (1) that DST nonsuppressors had significantly lower plasma dexamethasone levels than suppressors (p C .03). Similar trends were observed when the population was divided into depressed and nondepressed patients; (2) that mg/m’ dose of dexamethasone was directly correlated with plasma dexamethasone levels (p < .003) and inversely with post-dexamethasone plasma cortisol levels (p < .04); and (3) a statistically significant inverse correlation between plasma dexamethasone levels and post-dexamethasone cortisol levels (p < .04). Our findings show that dexamethasone dosage and plasma dexamethasone levels are important factors in evaluating DST results in psychiatrically disturbed children.

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DST IN DEPRESSED INPATIENT CHILDREN S. Yaylayan, E. Weller, R. Weller

VERSUS OUTPATIENT

Columbus. OH

The dexamethasone suppression test (DST) was studied in 63 depressed inpatient and 14 depressed outpatient children. All were prepubertal, aged 6-12. The Diagnostic Interview for Children and Adolescents-Child and Parent forms (DICA-C and DICAP) were used to establish criteria-based DSM-III diagnoses. All met DSM-III criteria for a major depressive episode and were moderately to severely depressed. Baseline cortisol levels were measured at 8 am and 4 pm. Then at 11 pm a 0.5 mg oral dose of dexamethasone was given. Cortisol levels were measured the next day at 8 am and 4 pm. The DST was considered positive if the serum cortisol level was 3 5 @dl. At 8 am 45% of inpatients and 42% of outpatients had positive DSTs. Sensitivity at 4 pm was 54% for inpatients and 50% for outpatients. Sensitivity for the DST-Either (i.e., the DST was positive at 8 am and/or 4 pm) was 67% for inpatients and 75% for outpatients. Sensitivity for DST-Both (DST was positive at both 8 am and 4 pm values) was 32% for inpatients and 8% for outpatients. This higher rate of nonsuppression at both sampling times among inpatients approached statistical significance (X2 = 3.48, p < .07). Mean post-dexamethasone cortisol levels were significantly higher for inpatients at 4 pm (6.7 -C 5.5 vs 4.1 + 3.3; t = 2.32; p < .025) and showed a tendency in this direction at 8 am (7.2 + 8.2 vs 4.8 + 5.0; t = 1.42; p < .lO). Thus, sensitivity of a single point DST was equal for depressed prepubertal inpatients and outpatients, but higher post-dexamethasone cortisol levels and positive two point DSTs were more typical of inpatients.