Depression is a risk factor for mortality after myocardial infarction: fact or artifact?
OBJECTIVE
This study sought to investigate the long-term impact of depression on cardiac mortality after myocardial infarction (MI) and to assess whether the timing of depression influences the findings.


BACKGROUND
Previous studies have shown that depression increases the risk of cardiac death after MI, although some studies with robust methodology have failed to show this effect. Clinical trials of depression treatments have failed to improve mortality. Until the relationship between depression and post-MI mortality is understood fully, clinical trials aimed at reducing mortality by treating depression remain premature.


METHODS
We recruited 588 subjects after MI and followed up their cases for up to 8 years. Patients underwent detailed assessments of cardiac status, conventional cardiac risk factors, and noncardiac illness at baseline. Depression was assessed for the period immediately preceding MI and at 12 months after MI, using a standardized questionnaire and a research interview. At follow-up, the mortality status, cause, and date of death were recorded for 587 subjects using population records.


RESULTS
Multivariate predictors of cardiac death included older age (hazard ratio [HR] = 1.04, p = 0.007), previous angina (HR = 1.8, p = 0.03), previous MIs (HR = 1.6, p = 0.004), Killip class (HR = 1.8, p = 0.005), beta-blockers (HR = 0.5, p = 0.023), and angiotensin-converting enzyme inhibitors (HR = 0.6, p = 0.047) prescribed on discharge. Depression was not associated with cardiac mortality, whether detected immediately before MI (p = 0.48), 12 months after MI (p = 0.27), or at both time points (p = 0.97).


CONCLUSIONS
The association between depression and post-MI mortality is complex, possibly being limited to depression immediately after MI. Defining the window when intervention for depression might benefit survival is crucial for the design of future trials.
Dickens
Chris
C
Psychological Medicine Research Group, Department of Psychiatry, Manchester University, Manchester, England. chris.dickens@manchester.ac.uk
McGowan
Linda
L
Percival
Carol
C
Tomenson
Barbara
B
Cotter
Lawrence
L
Heagerty
Anthony
A
Creed
Francis
F
D000368:Aged; D015897:Comorbidity; D003863:Depression / Q000453:epidemiology*; D003925:Diabetic Angiopathies / Q000453:epidemiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000453:epidemiology / Q000401:mortality*; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D016019:Survival Analysis; D013997:Time Factors