Major depression is associated with an increased risk of heart attack for middle-aged HIV-positive people, investigators from the United States report in JAMA Cardiology. Overall, presence of a major depressive disorder (MDD) increased the risk of heart attack – acute myocardial infarction (AMI) – by almost a third. Use of antidepressants weakened the association between depression and heart attack risk, and there was no evidence that milder forms of depression – dysthymic disorders – were associated with an elevated risk of heart attack.
It’s already known that depression is associated with an increased risk of cardiovascular disease (CVD) in the general population. The present study is the first research to show that major depression is also a heart attack risk factor for people with HIV.
“We report novel evidence suggesting that MDD is independently associated with AMI in the HIV-infected population,” comment the authors. “We found that MDD at baseline was associated with an increased risk for incident AMI over 5.8 years of follow-up. Specifically, after adjustment for demographics, CVD risk factors and HIV-specific factors, HIV-infected adults with MDD had a 30% greater risk for having an AMI than did HIV-infected adults without MDD.”
The investigators believe their research had identified a new target for cardiovascular disease prevention in HIV-positive people that should be explored in further studies.
Improvements in treatment and care mean that most people with HIV now have an excellent life expectancy. Diseases associated with older age are an increasingly important cause of illness and death in HIV-positive people, and prevention of cardiovascular disease is a care priority.
Research in the general population has shown that individuals with a depressive disorders are up to 60% more likely to develop cardiovascular disease compared to individuals with good mental health.
Investigators from the Veterans Aging Cohort Study wanted to see if there was a similar relationship between depression and heart attack risk in people with HIV.
They therefore designed a prospective study involving 26,144 HIV-positive people who entered care between 1998 and 2003. People were followed between 2003 and 2009 to see if the presence of a major or minor depressive disorder at baseline increased the risk of heart attack during follow-up. The investigators adjusted their findings in several models to take account of traditional cardiovascular risk factors, HIV-related factors, co-infection with hepatitis C virus (HCV), drug use and use of antidepressants.
The majority of participants (> 95%) were male and the average age at baseline was approximately 47 years.
A major depressive disorder is defined by psychiatrists as a period of at least two weeks of persistently low mood accompanied by symptoms such as feelings of worthlessness, anxiety, pessimism, impaired concentration, disturbed sleep, loss of interest in everyday activities, reduced energy, and sometimes, thoughts of death or suicidal feelings. On entry to the study, 19% of people had a major depressive disorder with a further 9% having a milder form of depression.
People were followed for a median of 5.8 years. During this time, there were 490 incident heart attacks (2% of study population).
People with a major depressive disorder at baseline had an increased risk of heart attack compared to those without major depression. The association was significant in models that took into account demographics (HR = 1.31; 95% CI, 1.05-1.62), cardiovascular risk factors (HR = 1.29; 95% CI, 1.04-1.60) and HIV-specific factors (HR = 1.30; 95% CI, 1.05-1.62).
The association was weakened but still of borderline significance when the investigators took into account other factors, such as HCV infection, substance abuse and haemoglobin level (HR = 1.25; 95% CI, 1.00-1.56).
The authors also adjusted their results to take account of baseline antidepressant therapy. Overall, use of antidepressants meant that the association between major depression and heart attack was no longer significant.
There was no evidence that milder forms of depression increased the risk of heart attack.
The investigators suggest several reasons why major depression increased the risk of heart attack for people with HIV, including:
- systemic inflammation
- changes in the autonomic nervous system
- poor health behaviours, such as smoking, a sedentary lifestyle and sub-optimal adherence to treatment
- social isolation.
“We report novel evidence that HIV-infected adults with MDD have a greater for AMI than HIV-infected adults without MDD after adjustment for many potential confounders,” conclude the investigators. “There is a need for clinical trials designed to evaluate the effect of high-quality depression treatment on CVD risk markers and incident events in HIV-infected adults with depression.”
Khambaty T et al. Association between depressive disorders and incident acute myocardial infarction in human immunodeficiency virus-infected adults Veterans Aging Cohort Study. JAMA Cardiol, doi: 10.1001/jamacardio.2016.2716.