The prevalence of coronary atherosclerosis among deployed USA service members who died during the past decade is 8.5%, which is markedly lower than rates observed in soldiers who served in the Korean and Vietnam wars.
This prevalence demonstrates a steep decline from the rates of 77% noted in the Korean War and 45% in the Vietnam War — researchers wrote in the Journal of the American Medical Association in December 2012.
JAMA 2012; 308:2624-2625.
Bryant J. Webber, MD, of the Uniformed Services University of the Health Sciences in Bethesda, Md., and colleagues conducted a study of 3,832 (mean age, 25.9 years; 98.3% men) members of the armed forces with available autopsy reports who died from combat-related or unintentional injuries in support of Operation Enduring Freedom and Operation Iraqi Freedom/New Dawn between 2001 and 2011.
Coronary atherosclerosis was classified as minimal (fatty streaking only), moderate (10% to 49% luminal narrowing of ≥1 vessel) and severe (≥50% narrowing of ≥1 vessel).
Prevalence of any coronary atherosclerosis was 8.5% (95% CI, 7.6-9.4); severe coronary atherosclerosis, 2.3% (95% CI, 1.8-2.7); moderate, 4.7% (95% CI, 4-5.3); and minimal, 1.5% (95% CI, 1.1-1.9). The researchers found that age was most strongly associated with prevalence of atherosclerosis. Service members with atherosclerosis were older than those without (30.5 years vs. 25.3 years; P<.001). Further, prevalence of atherosclerosis appeared to be approximately seven times higher in those aged at least 40 years vs. those aged 24 years or younger (45.9% vs. 6.6%).
Data also indicated that, compared with service members without conventional cardiovascular risk factors (11.1%), prevalence of atherosclerosis was greater among those with a diagnosis of dyslipidemia (50%), hypertension (43.6%) or obesity (22.3%).
In an accompanying editorial from the National Heart, Lung, and Blood Institute, highlighted these issues but also indicated these autopsy studies again show that coronary disease begins at a young age and even in a better risk controlled population group almost 1 in 2 soldiers over 40 have significant coronary atherosclerosis. Once again aggressive primary prevention is key.
Declines in cardiovascular disease risk factors in these military personnel have almost certainly contributed to the observed reductions in prevalence of subclinical atherosclerosis, incidence of clinical atherosclerotic disease, and deaths from heart disease. Although age-adjusted heart disease death rates have declined by 72% since their peak during the Vietnam War years, cardiovascular disease still remains the leading cause of death in the United States. The national battle against heart disease is not over; increasing rates of obesity and diabetes signal a need to engage earlier and with greater intensity in a campaign of pre-emption and prevention.
It is important to note that rates of obesity, smoking, hypertension, dyslipidemia, and impaired fasting glucose are markedly lower in USA military service members than in men and women of the same age in the civilian US population–making it possible to understand the high rate of poor general health in USA and high degree of sub clinical disease in “healthy” US individuals. While primary and secondary prevention have likely contributed equally to national declines in heart disease deaths, advances in primary, but not secondary, prevention most likely explain the declines in coronary atherosclerosis across the three autopsy studies.
Some great advances in primordial and primary prevention of atherosclerotic vascular disease have taken place over the past decade. In my next blog I will highlight some of the novel new approaches to prevent and minimise the clinical effects of atherosclerosis.