Lifetime History of Depression and Carotid Atherosclerosis in Middle-aged Women
Jones DJ, Bromberger JT, Sutton-Tyrrell K and Matthews KA;
Commented by , 21 Mar 2003
Background
Cardiovascular disease is the leading cause of mortality in women over 60. Subclinical atherosclerosis, as measured by B-mode ultrasonography carotid wall intima-media thickness (IMT) and plaque, is predictive of later clinical coronary events.
The association between depression and clinical coronary events is now well established. However, the association between depression and early subclinical cardiovascular disease remains elusive.
Purpose
To evaluate the link between lifetime history of psychopathologic conditions and subclinical carotid atherosclerosis in middle-aged women prior to menopause.
Methods
Participants included a random sample of 336 healthy, middle-aged women from 1 of 7 sites of SWAN, a longitudinal study of the perimenopausal transition in American women.
The Structured Clinical Interview for DSM-IV Axis I (SCID-IV) was used to diagnose current and lifetime mood, anxiety, and substance use disorders. B-mode ultrasonography was used to measure IMT and plaque.
Training, along with certification and reliability standards were achieved for SCID raters and ultrasonographers, who were blind to each others´ results. The following cardiovascular risk factors were obtained:
- Lipid profile
- Blood pressure
- Body mass index
- Physical activity (self-report instrument)
- Food frequency questionnaire
- Smoking history
Bivariate analyses examined associations between lifetime psychopathology and subclinical atherosclerosis. Significant associations were entered into more stringent multivariate analyses controlling for cardiovascular risk factors.
Results
More than one third of the sample had a lifetime history of major depression, 22% experienced an anxiety disorder and 15% a substance use disorder. Plaque was found in 14% of the sample. Lifetime history of a substance use disorder and major depression were significantly associated with a higher IMT score and plaque, respectively.
Lifetime history of anxiety disorders was not associated with IMT or plaque. After controlling for cardiovascular risk factors, only the association between major depression and plaque was maintained.
There was a 2-fold greater risk of plaque in women with a history of recurrent major depression relative to those with no history of depression (odds ratio = 2.29; 95% CI; 1.08-4.86). Conversely, women with a single major depressive episode (MDE) were not at greater risk.
Discussion
The results suggest that recurrent depression, but not a single depressive episode, is an important risk factor for early atherosclerosis in middle-aged women. Overall, the study is well designed, with good randomization techniques, reliable measures of psychopathology and subclinical atherosclerosis and blinding of raters.
Several limitations, however, are noteworthy. The lifetime history of MDEs relied upon a retrospective account, prone to bias. Family history of cardiovascular illness, a strong cardiovascular risk factor, was not included in the data collection.
Most importantly, correlation does not equal causation. As the authors point out a third factor may predict both recurrent major depression and plaque development.
Notwithstanding these limitations, the authors have provided an important contribution to our understanding of the depression-cardiovascular illness interface, with significant public health implications.
Identifying women with recurrent MDEs may prove valuable in the early identification of subclinical atherosclerosis. Furthermore, the opportunity to prevent atherosclerotic progression and subsequent coronary artery disease with effective psychotherapeutic and pharmacologic treatments of depression bears future study.
The absence of association between anxiety and subclinical atherosclerosis also merits further exploration, given the established association between anxiety and clinical coronary events (1,2). These studies, interestingly, studied males exclusively and raises the question of gender-specific contributions.
1. Kawachi I, Colditz GA, Ascerio A, Rimm EB, Giovannucci E, Stampfer MJ, Willet WC. Prospective study of phobic anxiety and risk of coronary heart disease in men. Circulation 1994;89:1992-1997.
2. Kawachi I, Sparrow D, Vokonas PS, Weiss ST. Symptoms of anxiety and risk of coronary heart disease: the Normative Aging Study. Circulation 1994;90:2225-2229.