Abstract 1522: Anxiety with Depression is Associated with Increased Platelet Reactivity In Stable Acute Coronary Syndrome Patients
INTRODUCTION: Platelets play a central role in the pathophysiology of acute coronary syndromes. Studies show psychological factors (depression and more recently anxiety) enhance the risk of recurrent events in ACS patients (pts), presumably by increasing platelet reactivity through serotonin (5HT) pathway. It has been hypothesized that anxiety may be a stronger predictor of cardiovascular prognosis.
HYPOTHESIS: Stable ACS pts with both depression and anxiety will have higher platelet reactivity than pts with only depression or pts with neither depression nor anxiety.
METHODS: Patients with ACS in prior 3 months (n=44) were assigned to 3 groups based on their scores on Beck Depression Inventory (BDI) and Hospital Anxiety and Depression Scale (HADS); Group A: no depression or anxiety, Group B: depression only and Group C: depression with anxiety. None of the pts had anxiety without depression. Cutoff for diagnosing depression was >9 on the BDI and for anxiety >7 on the HADS. Platelet aggregation was induced using ADP (5μM) and 2 doses of 5HT (4 and 10μM) mixed with epinephrine (Epi 4μM). All pts were on aspirin and clopidogrel. Patients on antidepressants or anxiolytics were excluded. All analyses are adjusted for age, sex, hypertension, lipid profile and smoking.
RESULTS: Platelet reactivity in response to 5HT was higher in the depressed and anxious group. No difference was noted in the 5HT mediated aggregations between groups A and B. ADP mediated platelet aggregation was similar among all 3 groups. In a multivariate linear regression model, HADS scores but not BDI scores were independent predictor of 5HT mediated platelet reactivity (both doses p<0.05).
CONCLUSION: Post ACS pts with depression and concurrent anxiety show significantly higher 5HT mediated platelet reactivity than pts with only depression or with no depression or anxiety, and thus may be a particularly high risk group. This highlights the importance of screening post ACS pts for both depression and anxiety.