Mr. Meijer is manager of scientific services for Bio-Imaging Technologies in Leiden, the Netherlands. Prof. Bots is an associated professor of epidemiology at the Julius Center for Health Sciences and Primary Care of the University Medical Center Utrecht, also in the Netherlands.
Several population studies have shown that a relatively simple measurement of carotid vessel wall thickness (carotid intima media thickness, or CIMT) made by carotid B-mode ultrasound (Figure 1) could detect atherosclerosis at an early stage. The test can also identify individuals at increased risk for atherosclerotic events, such as acute myocardial infarction or ischemic stroke.1-10 Clinics worldwide have begun to offer this noninvasive, low-cost risk-assessment service.
Data from long-running population studies can also be used to estimate an individual's "vascular age," that is, age based on the state of a person's blood vessels rather than that person's chronological age.11-13 Evidence suggests that when carotid artery vessel walls show signs of aging (thickening, plaques) before an individual's chronological age would warrant, that person has a higher risk of experiencing cardiovascular events sooner than an age-matched control.
The market for cardiovascular risk screening is evolving rapidly. Major players in the ultrasound industry have identified this opportunity and implemented CIMT measurement and reporting software into the vascular calculation packages of their ultrasound systems (Figure 2).
The growing interest in this area should be no surprise. Programs designed to prevent illness and to identify the presence of modifiable disease are becoming popular. More responsibility for well-being is being shifted from the state to individuals and employers with the intention of keeping the aging population fit and well, thereby reducing healthcare costs.
Cardiovascular disease is the number one killer in the Western world. CIMT screening of underlying atherosclerosis has the potential to create a new market for ultrasound manufacturers and prevention clinics. Screening followed by adequate, appropriate risk management could help prevent future vascular events. Several studies have shown that development of atherosclerosis can be slowed or even reversed by medication, change of lifestyle, change of diet, or a combination of all these approaches.9,14-18
The real challenge is to not only identify individuals at risk, but also engender changes in lifestyle and diet that will lower those individuals' risk of a cardiovascular event. CIMT may be a way to do this. Individuals who undergo screening can be shown signs of vascular damage directly, which should encourage them to comply with appropriate advice. The psychological impact of telling an apparently healthy person that significant plaque is present in his or her carotid artery—and probably elsewhere—endangering future health, should not be ignored. Professional guidance will be necessary to handle this type of communication.
