Assessment of Coronary Artery Calcium in Active Duty Enlisted Military Members With 10 or More Years of Service

While the military is making strides towards improving the health and habits of service
members, there are many aspects of the military culture that negatively affect the
cardiovascular health of military members. Smoking/tobacco use, poor eating habits with Meals
Ready-to-eat (MRE) and ready access to fast food establishments on base, inconsistent
exercise, the socioeconomic status of enlisted members and the stress of deployment are all
factors that contribute to increased risk of cardiovascular disease during military service.
Currently the calculation of a patient's Framingham risk score is the most commonly used
method of calculating a patient's cardiovascular risk, and this calculation is based on age,
smoking history, blood pressure, and lab values and compares it to a general population's
risk. By the use of a cardiac CT scan, a Coronary Artery Calcium (CAC) score can be
calculated and used to estimate the degree of atherosclerosis already present in each
patient's coronary arteries, and thus establishing their risk of future cardiovascular
events. CAC scoring is a more patient-specific way of identifying cardiovascular risk. The
purpose of this study is to assess the prevalence of atherosclerosis in enlisted military
members with at least 10 years of service and one or more cardiovascular risk factor and to
determine if their risk of a cardiovascular event is higher than predicted by the Framingham
score. If CAC scoring is demonstrated to be more accurate, particularly if it is more likely
to detect risk, it may be used in the future to better risk stratify this population of the
military. The CAC results in patients could also be a motivating factor to create changes in
the military culture to attempt to mitigate these risks and create a healthier fighting
force.

Inclusion Criteria:

- Active Duty Military Members with at least 10 years of service

- Enlisted Rank

- Males 35 years and older OR Females 45 years and older (please note the age difference
is due to the fact that female plaque formation with calcification has been shown to
lag that of males by about 10 years)

- One or More of the Following Risk Factors:

- Smoker - at least 5 pack years in the past 5 years (pack year = number of packs
per day * number of years of smoking)

- Diabetic (Fasting glucose of >125 mg/dL on two or more blood draws, or Random
Blood Glucose of >200 mg/dL on a single blood draw, or Hemoglobin A1C >6.5%, or
previous diagnosis of diabetes listed in the subject's medical record) or
Pre-diabetic (Fasting glucose >100 on two or more blood draws or Hgb A1C 5.7-6.4)

- Hypertension (Systolic BP > 140 or Diastolic BP >90 or on blood pressure
medications or diagnosis of hypertension in medical record)

- Waist Circumference > 40 inches for males or >35 inches for females

- Hyperlipidemia (LDL>130, HDL<40 for males, HDL <50 for females, Triglycerides
>200, on lipid lowering medications and/or diagnosis of hyperlipidemia in medical
record)

Exclusion Criteria:

- Males <35 years old

- Women <45 years old (please note the age difference is due to the fact that female
plaque formation with calcification has been shown to lag that of males by about 10
years)

- Officer Rank - officers are excluded as we are looking at the enlisted culture in the
military.

- History of any of the following:

Coronary Artery Disease (CAD) Coronary Artery Bypass Grafting (CABG) Myocardial Infarction
(MI) Percutaneous Intervention/Stent Placement (PCI) Angina

- Recent significant radiation exposure - PET scan, Nuclear Bone Scan or Nuclear Study,
or repeated imaging over the past 12 months for a condition (ex. repeated x-rays for
ankle fracture/surgery or repeated abdominal CTs for obstruction, etc.)

- Females who think they may be pregnant

- Pregnant females