No Link Found between Hepatitis C Infection and Heart Attacks

Some recent research has linked hepatitis C virus (HCV) infection with carotid atherosclerosis ("hardening of the arteries"), insulin resistance, and other risk factors for heart attacks.

But a case-control study reported in the September 15, 2006 electronic edition of Clinical Infectious Diseases found no association between HCV seropositivity and elevated risk of acute myocardial infarction (MI).

The study involved an established cohort of men aged 30-50 years on active duty in the U.S. Army during 1991-2000. Case patients were individuals who were hospitalized for a first MI during this period, but had no prior history of hospitalization for cardiovascular disease. Control subjects were men with no history of MI and no hospitalization for cardiovascular disease, matched to case patients by age and race/ethnicity.

Researchers collected self-reported data on health risk factors including past and current smoking habits, work stress, and diabetes, as well as measurements for height, weight, blood pressure, and serum cholesterol level. Stored serum samples were tested for HCV antibodies.

Results

HCV test results and demographic data were available for 292 case patients and 290 control subjects.

The mean age was 40 years, 61% were white, and there were no significant differences with respect to military rank, but case patients tended to be less educated and were more likely to be married.

Overall, 52 participants tested positive for HCV antibodies, a prevalence of 8.9%; the rate of HCV infection was significantly higher among blacks (13.2%) compared with whites (6.8%) and subjects from other racial/ethnic groups (9.4%) (P < 0.05).

There was no significant difference in the prevalence of HCV infection between patients who had heart attacks (7.6%) and control subjects (9.8%) (P = 0.44).

No association was found between HCV positivity and acute myocardial infarction (relative risk 0.91; 95% CI 0.52-1.61); this remained true after adjusting for age, race, education, and marital status (adjusted relative risk 0.94; 95% CI 0.52-1.68).

Increased risk of acute myocardial infarction was significantly associated with current smoking, high cholesterol, and work stress; there was a borderline significant association with high serum levels of Chlamydia pneumoniae bacteria.

In contrast, high blood pressure and being overweight were not associated with an increased MI risk (however, obese patients and those with severe hypertension are not eligible for active duty, so were not included in this study).

Conclusion

The researchers concluded that, "The results of this study do not indicate any relationship between HCV seropositivity and acute myocardial infarction and do not support previous reports in the literature of this association."

However, they noted that active duty military personnel tend to be in good health overall and are younger than the average age at which heart attacks typically occur.

09/01/06

Reference
C M Arcari, K E Nelson, D M Netski, and others. No Association between Hepatitis C Virus Seropositivity and Acute Myocardial Infarction. Clinical Infectious Diseases 43(6): e53-e56. September 15, 2006.