Screening for Coronary Heart Disease (CHD)
For asymptomatic men and women with no history of CHD or CHD risk equivalents (established forms of atherosclerotic diseases including abdominal artery aneurysm (AAA), peripheral artery disease (PAD), and symptomatic carotid artery disease), the American College of Preventive Medicine (ACPM) recommends the use of a CHD risk assessment tool such as the Framingham Risk Score (FRS) to assess CHD risk and to guide risk-based therapy. Individuals with a high (>20% for 10-year) risk of CHD benefit from intensive risk factor modification (e.g., lipid-lowering, blood pressure–lowering therapies), and appropriate chemoprophylaxis (e.g., aspirin, statin therapy).
ACPM does not recommend routine screening of the general adult population using electrocardiogram (ECG), exercise treadmill testing (ETT), electron-beam computed tomography (EBCT), ankle–brachial index (ABI), carotid intima medial thickness (IMT), or emerging risk factors including high-sensitivity C-reactive protein (hs-CRP). However, ACPM recognizes that hs-CRP appears to contribute to CHD risk assessment independent of traditional risk factors and has the potential to guide intensity of risk-reducing therapies in selected people. Therefore, clinicians who identify patients having an intermediate (10%–20% over 10 years) risk of CHD should consider hs-CRP testing to determine the need for intensification of therapy or pharmacotherapy (e.g., statins). However, the net benefit of such therapy based on this strategy is unclear because of lack of data.
Screening for Carotid Artery Stenosis (CAS)
ACPM does not recommend routine screening of the adult population for asymptomatic CAS. Although stroke is a leading cause of mortality and morbidity, a relatively small proportion of disabling and unheralded strokes is due to CAS. Duplex ultrasonography has moderate sensitivity and specificity for detecting severe CAS but may yield false-positive results that could lead to unnecessary and potentially invasive testing (e.g., angiography) with adverse consequences. Although carotid endarterectomy (CEA) decreases the risk of stroke among study participants with asymptomatic CAS, the effect of treating CAS in populations screened for CAS is uncertain because of lack of studies. Further, the benefits of CEA are expected to be less among asymptomatic individuals in the general population compared to study participants. The authors agree with the United States Preventive Services Task Force (USPSTF) that for individuals with asymptomatic CAS there is moderate certainty that the benefits of screening do not outweigh the harms.
Screening for Peripheral Artery Disease (PAD)
The authors agree with the USPSTF that screening for PAD among asymptomatic adults in the general population is expected to have few or no benefits because of the low prevalence of PAD in this group. There is also little evidence that treatment of PAD at this asymptomatic stage of disease, beyond treatment based on standard cardiovascular risk assessment, improves health outcomes. Most of the literature on PAD pertains to treatment of symptomatic patients, and there is little data directly examining the efficacy of PAD screening among asymptomatic adults in the general population or in higher-risk adults.
Existing evidence supports the use of increased physical activity and smoking cessation to improve outcomes among people with early PAD. However, these interventions should be offered to all patients to encourage healthy lifestyles, and do not necessarily offer additional benefit for people with screen-identified PAD. Finally, screening asymptomatic adults with the ABI could potentially lead to some small degree of harm, including false-positive results and unnecessary workups. Therefore, the potential harms associated with routine PAD screening in asymptomatic adults would exceed the potential benefits.
ACPM does not recommend routine screening for asymptomatic PAD in the general adult population. However, clinicians should be alert to symptoms of PAD in people at increased risk (e.g., people aged >50 years, smokers, and individuals with diabetes) and evaluate patients who have clinical evidence of vascular disease. Therapeutic lifestyle changes including a heart-healthy diet, regular exercise, and smoking cessation should be encouraged in addition to other pharmacologic risk reduction strategies for individuals at risk for PAD.
Screening for Abdominal Aortic Aneurysms (AAA)
AAAs are an important medical issue especially in groups in which the prevalence is high, namely, men aged >65 years who have ever smoked. Ruptured AAAs are often catastrophic events. Ultrasonography is a safe, noninvasive, reliable screening test that can identify AAAs and allow clinicians to take the necessary steps to substantially decrease the morbidity and mortality associated with AAAs.
The ACPM agrees with the recommendations of the USPSTF for one-time screening in men aged 65–75 years who have ever smoked. The College does not currently recommend routine screening in women because it has not been shown to provide any benefit in relation to AAA-related mortality or in decreasing the incidence of ruptured AAAs.