Depression and cardiovascular morbidity and mortality: cause or consequence?

Area of Science:

• Cardiology
• Psychiatry
• Public Health

Background:

• Depression following myocardial infarction is linked to increased cardiovascular mortality.
• This study investigated the association between depressive symptoms and adverse outcomes in patients with a history of acute coronary syndrome.

Purpose of the Study:

• To assess if depressive symptoms correlate with adverse cardiovascular outcomes.
• To explore potential explanations for any observed associations.

Main Methods:

• 1130 participants from the LIPID Study with a history of acute myocardial infarction or unstable angina were assessed for depressive symptoms using the General Health Questionnaire.
• Data on cardiovascular symptoms, general health, risk factors, employment, social support, and life events were collected.
• Cardiovascular death, non-fatal myocardial infarction, stroke, and unstable angina were tracked over a median of 8.1 years.

Main Results:

• Individuals with depressive symptoms (22%) reported more angina, dyspnoea, poorer general health, and adverse life events.
• A modest association was found between depressive symptoms and cardiovascular events (HR 1.42), but not cardiovascular death.
• After adjusting for cardiovascular symptoms, employment, social support, and life events, the association between depressive symptoms and cardiovascular events was no longer significant.

Conclusions:

• No significant association exists between depressive symptoms and fatal or non-fatal cardiovascular events when adjusted for cardiovascular symptoms.
• The previously observed link between depression and cardiovascular mortality might not be causal.