Psychological and physiological effects of caring for patients with treatment-resistant depression.

BACKGROUND: Carers of patients with psychiatric disorders show high levels of anxiety and depression, possibly mediated through disruption of the hypothalamo-pituitary-adrenal (HPA) axis. Among carers of patients with treatment-resistant depression (TRD), we set out to determine the psychological and physiological (HPA axis) consequences of caring, and the association of these consequences with long-term outcome in patients. METHOD: Thirty-five informal carers of patients with severe TRD requiring in-patient treatment were recruited and compared with 23 controls. HPA-axis activity was assessed by measuring post-awaking salivary cortisol. The Involvement Evaluation Questionnaire (IEQ) and the General Health Questionnaire-12 (GHQ-12) were administered to measure carer burden and psychiatric caseness respectively. Independent t tests were used to compare differences between carers and controls and a linear regression model was used to determine the association of post-awakening cortisol with carer status while controlling for confounding variables. Data on long-term patient outcome (12 to 83 months), measured using the Hamilton Depression Rating Scale (HAMD), were also obtained and linear regression was used to determine the association between cortisol output in carers and remission status in patients. RESULTS: Carers experienced high carer burden and high psychiatric caseness. Carers showed reduced cortisol output after awakening, calculated as the area under the curve with respect to ground (AUCg), which remained significant after controlling for potential confounders. In a linear regression model, non-remission in patients was associated with reduced cortisol output in carers. CONCLUSIONS: Caring for patients with TRD is associated with adverse psychological and physiological changes suggesting hypocortisolism post-awakening. These changes are associated with poor patient outcome.

Discrepancy between subjective and objective severity in treatment-resistant depression: prediction of treatment outcome.

OBJECTIVE: Identifying predictors of outcome among patients with treatment-resistant depression (TRD) is challenging. We hypothesised that discrepancy between self-rated and observer-rated scales may be a simple way of making such a prediction. METHOD: 102 patients were admitted to a unit specialising in the treatment of resistant depression and underwent fortnightly assessment with clinician-rated (Hamilton Depression Rating Scale-21, HAM-D) and self-rated (Beck Depression Inventory, BDI) measures. All patients had significant depressive symptoms that were treatment resistant, 70% as part of a major depressive disorder and the remainder as part of a bipolar or other disorder. A discrepancy score between the HAM-D and BDI was calculated on admission and its association with patient clinico-demographic factors was determined. A subset of 67 patients remained as inpatients for 40 weeks or until clinical response and were entered into a responder analysis, in which response was defined as ≥50% reduction in admission HAM-D score. The association of the admission BDI-HAM-D discrepancy score with subsequent patient response, was determined. RESULTS: The magnitude of BDI-HAM-D discrepancy was higher in those with co-morbid personality disorder, lower in those with psychosis and positively correlated with anxiety. High BDI-HAM-D discrepancy score predicted delayed treatment response (odds ratio 5.40, p = 0.005). CONCLUSION: Within TRD, higher discrepancy predicts slower response to treatment independent of objective illness severity; this may be mediated by underlying personality traits and co-morbid anxiety.