Although the available evidence strongly supports an association between depression and coronary heart disease (CHD), the possible biological link between these two conditions still remains to be clarified. The hypothalamus-pituitary-adrenal (HPA) axis is the main endogenous system mediating the stress response and changes in cortisol secretion have been associated with depressed mood in patients with CHD. Therefore, the study of the correlation between cortisol levels and depressed mood in acute coronary syndrome (ACS) patients could help to clarify the nature of the relationship between ACS and the risk to develop a depressive syndrome.

We aimed to explore the relationships between HPA axis activity and depressed mood in ACS patients.

The purpose of this study was to determine whether the cortisol awakening response (CAR) is associated and/or predict depressive symptoms in patients with an ACS.

Patients admitted to an ACS ward were asked to fill in the Beck Depression Inventory (BDI) and to collect saliva samples in the morning to measure their CAR. All the procedures were carried out within 1 week after an ACS. Patients were asked again to fill in the BDI six months after their ACS.

A lower CAR was associated with higher BDI scores after 6 months from an ACS.

Our preliminary results suggest that hypoactivity of the HPA axis in the first week of an ACS may predict more severe depressive symptoms after 6 months from the ACS.