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Etiology

Anxiety symptoms predicted sudden death but not nonfatal coronary heart disease

ACP J Club. 1995 May-June;122:79. doi:10.7326/ACPJC-1995-122-3-079


Source Citation

Kawachi I, Sparrow D, Vokonas PS, Weiss ST. Symptoms of anxiety and risk of coronary heart disease. The Normative Aging Study. Circulation. 1994 Nov;90:2225-9.


Abstract

Objective

To determine if an association exists between symptoms of anxiety and risk for coronary heart disease.

Design

Case-control study nested within a 32-year cohort analytic study of participants in the Normative Aging Study.

Setting

Community-based study in Boston.

Participants

402 men (mean age, 45 y) who developed incident coronary heart disease between the baseline examination in 1961 and March 1993. Control participants were the 1869 men (mean age, 41 y) who remained free of coronary heart disease during the same follow-up period.

Assessment of Risk Factors

An anxiety symptom scale was constructed by selecting 5 items from the Cornell Medical Index and was administered to all participants at baseline. The score on the anxiety symptom scale ranged from 0 to 5, with higher scores indicating higher levels of anxiety. The baseline examination also included a medical history, physical examination, and pertinent biochemical laboratory tests.

Main Outcome Measure

Coronary heart disease, which included nonfatal myocardial infarction (MI), angina pectoris, and coronary heart disease deaths categorized into sudden or nonsudden coronary heart disease deaths.

Main Results

Among men who scored ≥ 2 on the anxiety symptom scale, the age-adjusted odds ratio (OR) for fatal coronary heart disease was 3.20 (95% CI, 1.27 to 8.09) compared with men who scored 0. After adjustment for cigarette smoking, body mass index, blood pressure, serum cholesterol level, family history of heart disease, and alcohol consumption, the multivariate OR for fatal coronary heart disease fell to 1.94 (CI, 0.70 to 5.41). The multivariate OR for sudden cardiac death was 2.96 (CI, 1.02 to 8.55) for men who scored 1 on the anxiety scale compared with men who scored 0 and was 4.46 (CI, 0.92 to 21.6) for men who scored ≥ 2 on the anxiety scale compared with men who scored 0. No increases were noted in either the age-adjusted ORs or the multivariate ORs for total coronary heart disease, nonfatal MI, or nonfatal coronary heart disease (nonfatal MI and angina pectoris), according to levels of anxiety symptoms.

Conclusions

After adjustment for appropriate potential confounding variables, symptoms of anxiety were not associated with nonfatal coronary heart disease. An association between anxiety and sudden cardiac death may exist.

Source of funding: Veterans Administration.

For article reprint: Dr. I. Kawachi, Department of Health and Social Behavior, Harvard School of Public Health, 677 Huntington Avenue, Boston MA 02115. FAX 617-432-3755.


Commentary

The main observation from this study was that anxiety symptoms do not appear to predict the development of nonfatal coronary heart disease but appear to be associated with increased risk for sudden cardiac death. This observation is consistent with the results of 2 other studies (1, 2).

The number of sudden cardiac deaths was small (n = 26) even after 32 years of observation, and only 2 deaths occurred in the highest anxiety category. This finding decreases confidence in the results. Further analyses after the occurrence of additional incident cases of fatal and nonfatal cardiac deaths may give a clearer result. A longer follow-up period is particularly desirable because the youngest members of the original cohort are now entering the age group in which these events are most likely to occur.

The importance of the result of this study is that it will enable the investigators to define the hypothesis and design the next analysis of the data to more specifically address the question of sudden cardiac death. If these observations continue to be confirmed, they may enable coronary heart disease to be divided into at least 2 different diseases: chronic nonfatal coronary heart disease that is not associated with symptoms of anxiety and acute sudden cardiac death that is associated with symptoms of anxiety. These 2 conditions may require different forms of treatment for a better preventive strategy and longer survival.

For future studies, it is most important to define both the specific symptoms of anxiety that are risk factors for sudden cardiac death and the characteristics of persons who are at greater risk for death. This is important both for defining the specific disease and determining the best treatment.

Marise S. Gottlieb, MD
Imreg, Inc. Cambridge, Massachusetts