Cortisol levels in unmedicated patients with unipolar and bipolar major depression using hair and saliva specimens

Andrés Herane-Vives,Valeria De Angel,Anthony J Cleare,Kia-Chong Chua,Andrew Papadopoulos,Luis Alameda,Danilo Arnone,Toby Wise,Allan H Young

doi:10.1186/s40345-020-0180-x

Abstract

BackgroundDifferentiating between unipolar and bipolar depression can be clinically challenging, especially at first presentation. Patterns of cortisol secretion could aid diagnostic discrimination in affective disorders although there has been little comparative research to date. In this study, we investigated acute (saliva) and chronic (hair) cortisol levels concurrently in unmedicated unipolar and bipolar disorders by using conventional diagnostic criteria and self-report measures.MethodsPatients with unipolar and bipolar major depression and healthy controls were recruited and assessed. Cortisol levels were extracted from saliva and hair specimens. Depressive features were investigated according to diagnostic groups and with a continuous self-report measure of bipolarity using the Hypomania Checklist (HCL-33).ResultsWhilst a trend towards a reduction in the total daily salivary cortisol output—area under the curve with respect to the ground (AUCg)—was detected in depressive disorders across diagnosis, the self-administrated bipolarity index suggested that an increase in bipolarity symptoms predicted lower cortisol levels using AUCg. Chronic cortisol measurement did not discriminate unipolar from bipolar depression.ConclusionResults suggested that whilst a low total daily salivary cortisol output (AUCg) might be associated with depressive symptoms, a self-reported measure of bipolarity predicts lower daily cortisol output.

Highlights

Early detection of bipolar depression can be clinically challenging as major depression is the commonest first clinical presentation for both unipolar and bipolar disorders
Hair can be used to reliably sample chronic cortisol concentrations in humans (Russell et al 2012), whereas the measurement of cortisol in saliva samples is a wellestablished approach to evaluate acute concentrations and variations in levels. Using such an approach previously, we found, for instance, that atypical depression may be better described by alterations in cortisol rhythm, rather than total concentration, when short and long-term cortisol levels were concurrently collected in 1 day (Herane-Vives 2018)
Patients were included if they met axis I DSM-IV criteria for unipolar major depression (59) or bipolar (12) disorder

Summary

Introduction

Detection of bipolar depression can be clinically challenging as major depression is the commonest first clinical presentation for both unipolar and bipolar disorders. In the case of bipolar type II disorder, symptoms can be difficult to detect based on their relatively shorter duration and propensity to lesser intensity than bipolar type I. The crude application of diagnostic criteria based on the unipolar vs bipolar dichotomy can frequently result in underreporting of bipolar disorder, potentially worsening clinical outcome as the treatment for the two conditions differs (Angst et al 2011). It is clearly important to achieve correct syndromic differentiation, not least to optimise treatment and clinical outcome (Sharma et al 2005), the absence of salient clinical features to guide differentiation of unipolar from bipolar depression is largely part of the current diagnostic limitations (Benazzi et al 2002). We investigated acute (saliva) and chronic (hair) cortisol levels concurrently in unmedicated unipolar and bipolar disorders by using conventional diagnostic criteria and selfreport measures

Methods

Results

Conclusion