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Three Tai Chi instructors auditioned and were selected by one of the investigators (FL) to teach the classes. All instructors had a minimum of 10 years prior Tai Chi teaching experience and came from different ethnic and cultural backgrounds. The Tai Chi intervention was the classical 24-Form Yang style incorporating elements of balance, postural alignment, and concentration (China National Sports Commission, 1983; Yan & Downing, 1998).
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Participants in the intervention group attended a 60-minute Tai Chi practice session twice a week for 6 months. The sessions consisted of a 15-minute warm-up, 30-minutes of Tai Chi, and a 15-minute cool-down period. During the practice, participants were led by an instructor and replicated the motions, postures, and speed of movement of the instructor.
Participants in the control group were instructed to maintain their routine daily activities and not to begin any new exercise programs. These participants were promised a 4-week Tai Chi program at the end of the 26-week intervention study period.

Measures
Background information. A short inventory was administered at baseline to assess demographic characteristics such as age, gender, education, income, and race/ethnicity.
Health-Related Quality of Life. HRQL was assessed with the Short-Form General Health Survey (Stewart et al., 1988) measured at baseline (Week 1), middle (Week 12), and termination (Week 24) of the study. The SF-20 was designed for use in clinical practice, research, health policy evaluation, and general population surveys. The SF 20 has proven useful in monitoring general and specific populations, comparing the burden of different diseases, differentiating the health benefits produced by different treatments, and in screening individual patients. The instrument comprises twenty items representing six domains of HRQL: physical functioning, role functioning, social functioning, bodily pain, mental health, and health perceptions. Each is defined below.
Physical function was assessed by six items assessing the extent to which health interferes with a variety of activities (e.g., carrying groceries, climbing stairs, and walking). Each item was measured on 3-point scale ranging from 1 (= limited for more than 3 months) to 3 (= not limited at all). Higher scores indicate better physical functioning.
Role functioning was assessed by two items assessing the extent to which health interferes with usual daily activity such as work or housework. Each item was measured on a 3-point scale ranging from 1 (= yes, for more than 3 months) to 3 (= no). Higher scores indicate better role functioning.

A single item determined participants levels of social functioning and measured the extent to which health interferes with normal social activities such as visiting with friends during past month. This item scale was measured on a 6-point scale ranging from 1 (= none of the time) to 6 (= all of the time) with higher scores indicating better social functioning.
Mental health was assessed by five items assessing general mood or affect, including depression, anxiety, and psychological well-being during the past month. Each item was measured on a 6-point scale ranging from 1 (= all of the time) to 6 (= none of the time) with higher scores representing better mental health.

The health perceptions dimension used five items designed to provide overall ratings of current health in general. Each item was measured on a 5-point scale from 1 (= definitely true) to 5 (= definitely false). Higher scores represent better health perceptions.

The scale of bodily pain was measured by a single item assessing the extent of bodily pain in previous four weeks. This item was measured on a 5-point scale from 1 (= none) to 5 (= severe). The bodily pain subscale was recoded so that a high score represents less pain.

Research to date has indicated health-related benefits of Tai Chi for older adults including improved balance control (Tse & Bailey, 1991) and reduction in the incidence of falling (Wolf et al., 1996; Li, Fisher & Harmer, in press), improved cardiovascular fitness (Lan et al., 1998; Lan et al., 1999; Young et al., 1999), enhanced psychological well-being (Li et al., 2001a) and increased perceptions of self-efficacy (Li et al., 2001b; Li et al., in press), and physical function (Li et al., 2001c). Less is known, however, about the effects of Tai Chi on overall health-related quality of life (HRQL). Given that the most important long-term endpoint for any practical and therapeutic intervention is not just improved physical and psychological benefits for its participants but enhanced HRQL, research is needed to establish the quantitative relationships between Tai Chi exercise and HRQL in older adults.

However, only one study to date (Kutner et al., 1997) has examined the relationship between Tai Chi and HRQL measures defined by the generic Health Status Battery (Ware & Sherbourne, 1992. Also known as MOS SF-36). In a 15-week intervention program, Kutner et al. (1997) compared Tai Chi practice group with balance training and education groups and reported no significant differences between intervention groups or any differences over time in perceived health status assessed by the Health Status Battery. Given the relatively short training period (15 weeks) employed, these findings may not be surprising. Determining the long-term effects of Tai Chi interventions on HRQL is warranted.
The purpose of this study was to extend our knowledge of Tai Chi’s effects on HRQL by examining its influence on multidimensional health status using a well-established medical outcome measure: the General Health Survey (Stewart et al., 1988). These self-report health survey data, which have not been previously reported, reflect participants’ perceptions of their function and well-being. Specifically, we examined the effects of a 6-month Tai Chi intervention on physical-, role-, and social-functioning, bodily pain, mental health, and change in health perceptions. It was hypothesized that Tai Chi practice would enhance these HRQL measures and that these changes would be characterized by mean changes that differed between the experimental and control groups.
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Participants were community-dwelling older adults recruited from a rural city in the Willamette valley, Oregon. Full details of recruitment and randomization are described elsewhere (i.e., Li et al., 2001a; Li et al., 2001c). Briefly, a total of 148 individuals responded to local newspaper advertisements and flyers at senior centers seeking volunteer participation in a longitudinal physical activity study. Inclusion criteria were: (a) aged 65 years or above, (b) low active, defined as non-involvement in a regular exercise program in the month prior to participation in the study, (c) healthy to the degree that participation in an exercise program would not exacerbate any existing health condition, and (d) willingness to be randomly assigned to a treatment condition. To screen for prior physical activity level, each respondent was interviewed by telephone using the Physical Activity Scale for the Elderly (Washburn et al., 1993).
Ninety-eight respondents (ranging from 65 to 96 years old (M age = 73.2 years, SD = 4.9), who met the inclusion/exclusion criteria and provided written informed consent before entry into the study, were randomized into the experimental conditions using a list of random numbers. Four individuals withdrew prior to the intervention. Of the remaining 94 qualified participants, 49 were assigned to the intervention group of Tai Chi practice (M age = 72.8, SD = 4.7) and 45 were assigned to a wait-list control group (M age = 72.7, SD = 5.7).

This study examined the effects of a 6-month Tai Chi exercise program on health-related quality of life (HRQL) in older individuals. Using a randomized controlled trial, ninety-four local community-residing volunteers aged 65-96 (M age = 72.8 years, SD = 5.1) were randomly assigned to a 6-month, twice a week, Tai Chi condition or a wait-list control condition. The Short-Form General Health Survey (SF-20) was used to assess change in multiple dimensions of health status involving physical-, social-, and role-functioning, bodily pain, mental health, and health perceptions. Results showed that, compared to the control group, participants in the Tai Chi group reported significant improvements in all functional domains of HRQL over the course of the 6-month intervention. It was concluded that a 6-month Tai Chi exercise program is effective for improving HRQL among older adults. Tai Chi, a self-paced and low intensity activity appears to be an effective, low-cost approach for promoting health in older persons.

Accumulating research suggests that physical exercise may be an effective strategy for optimizing health-related quality of life (HRQL) (McAuley & Katula, 1998). Several studies have demonstrated a positive relationship between physical activity and HRQL in the elderly (McMurdo & Burnett, 1992; Ruuskanen & Ruoppila, 1995; Wood et al., 1999) (for a review see King et al., 1999; McAuley & Rudolph, 1995). Whereas higher-intensity exercise programs offer significant health benefits (Fiatarone et al., 1990; King, Rejeski, & Buchner, 1998), in the later years of life such programs are more likely to be associated with increased rates of injury (Pollock et al., 1991). Additionally, many training programs require expensive and technically sophisticated equipment and highly qualified staff (Blair & Garcia, 1996). Therefore, a cost-effective and low-to-moderate intensity exercise program aimed at slowing age-related physiological and psychological decline and preventing disability should be considered for maximizing HRQL for older persons and improving long-term adherence to healthy behaviors (Centers for Disease Control & Prevention, 2001 – National Blueprint).

Tai Chi is a traditional form of Chinese exercise that can promote health and fitness, prevent disability, and maintain physical performance in later life. It is particularly suitable for older adults because it entails whole body weight-bearing conducted in a slow, controlled fashion. Its movements reflect physical skills required for useful independent locomotion including weight shifting with changing center of gravity and turning (Li, Fisher, Harmer & Shirai, 2003; Wolf et al., 1997). In addition, Tai Chi emphasizes the importance of psychosomatic integration for optimal health by integrating meditation and concentration components with the physical. Finally, from a pragmatic standpoint of cost and convenience, Tai Chi is an attractive activity because it does not require any special equipment and can be practiced any time or anywhere, once the basics have been learned (Li et al., 2003). Given the transportation and other barriers often encountered by older individuals, these features should enhance involvement and adherence.

Eligible entries were received from 76 students at 14 schools in the Arlington, VA and Washington, DC school districts. Almost all of the posters showed a good knowledge of nutrition by the students. The posters displayed a variety of themes around healthy eating, and the level of creativity and artistic talent was very high. It is not known whether any of the schools requested the Dole Foods educational aterials. Some of the teachers who gained the participation of their students were art or physical education teachers.

The poster entries were displayed in the main entryway of the national SOPHE conference, and an awards ceremony was held for the winners on November 6, 2004 (see Slideshow 1 .EXE or .ZIP). Many of the children enjoyed the ceremony with their family members and/or teachers joining them.

Discussion
It was encouraging to see that almost all of the posters developed by the children displayed a great knowledge of which foods are healthy for them. It is not known how much educational assistance was provided by the teachers. It could be that these students learned about healthy eating in conjunction with this contest, or the students who chose to enter may have already been aware of which foods were healthy for them. It would be interesting in a future project to be able to track the awareness of healthy foods and eating habits of children before and after a similar contest to determine if participation would influence knowledge and/or eating patterns.

The children seemed motivated by the monetary reward and the awards ceremony. They also enjoyed showing off their works of art to their family members and teachers before and after the ceremony.
The schools proved to be a good method of publicizing the contest. However, it is recommended to contact the schools more than six weeks prior to the deadline to allow for more time to reach the most appropriate people in the school districts to help promote the contest.

Summary
National Health Education Week themes that are specific to children should encourage participation among schools, teachers and parents. The partnership between SOPHE, NCHE, SNP-SOPHE, NCA-SOPHE and Charter Health Plan offers possibilities for dissemination of other public health education campaigns. Furthermore, a children’s poster contest about healthy eating in schools in the Washington, DC area was successful in gaining 76 entries from 14 schools. Children in 3rd through 5th grades displayed a high level of knowledge of which foods were healthy for them and a high level of creativity and artistic talent. The children with the winning posters received cash prizes and were honored at an awards ceremony in their honor.

Since 1995, National Health Education Week (NHEW) has been recognized as a federal health observance and is solely sponsored by the National Center for Health Education (NCHE). NHEW is celebrated during the third week of October. Since 1998, SOPHE has partnered with the National Center for Health Education to focus national attention on a major public health problem, provide public education on the issue and improve consumer’s understanding of the role of health education in promoting the public’s health. Each year a theme is selected for the week, materials and resources related to the theme, and program planning activities are developed, and disseminated to health education professionals and other stakeholders. Past themes have included healthy living, pediatric diabetes, asthma, medicine education, physical activity related to reducing obesity, and healthy eating related to reducing obesity.

A poster contest for children was conducted through schools in the Washington, DC metro area in conjunction with the 2004 National Health Education Week’s campaign, “Healthy Eating – Every Bite Counts!”. The contest encouraged children in 3rd, 4th, and 5th grades to learn about good nutrition and display their knowledge in an attractive poster. Six winners were chosen for each grade, and they were honored with their prizes at the Society for Public Health Education (SOPHE) annual meeting on November 6, 2004.

The contest was co-sponsored and developed jointly by the Student and New Professional Caucus of SOPHE (SNP-SOPHE) and the National Capital Area chapter of SOPHE (NCA-SOPHE). Financial assistance was provided by Chartered Health Plan, a Washington, DC-based managed health care company for Medicaid beneficiaries receiving Temporary Assistance for Needy Families (TANF). Educational assistance came from the Dole Food Company.

The contest was open to children in 3rd, 4th, and 5th grades in the Washington, DC area. Children were requested to develop a poster on 8-1/2 x 11 paper that depicted the theme of “Healthy Eating – Every Bite Counts!”. The contest was publicized to the schools by contacting the major school district offices in the Washington, DC area approximately 6 weeks before the deadline with a phone call, an official letter, and a flyer that they could distribute to their teachers and students. In addition, participating schools could receive nutrition and educational materials from Dole Foods, including Dole’s “5 A Day Adventures” CD-ROM. The popular “5 A Day Adventures” engages students in fun, action-packed adventures in “5 A Day Land” as they learn about nutrition, physical activity, and the importance of eating 5 to 9 servings of fruits and vegetables a day.
In addition to the primary National Health Education Week theme, interested students could develop their own slogans around healthy eating. Some suggestions were given in the letter to the schools, such as:
• Put a Rainbow on Your Plate (Dole 5-A Day Campaign)
• Eat enough fiber to prevent certain kinds of cancers.
• Healthy eating helps you get up and go!
• Healthy eating puts a tiger in your tank
• Fish is a good way to get lean protein

The posters were collected from the students and judged by grade level. Judging was performed individually by members of SNP-SOPHE and NCA-SOPHE. Each poster received at least four scores, and all grade levels were judged separately by the same set of judges. All identifying information such as name of the child and school was removed for judging.

Triglycerides are a primary source of energy and their levels in the periphery vary significantly. Historically, it has been understood that high VLDL and triglyceride levels were the result of elevated total cholesterol and lower levels of HDL cholesterol (Ginsberg, 1999; Tulenk & Sumner, 2002), but recent studies have shifted elevated triglyceride levels from an association with CAD to an independent predictor of the disease (Cullen 2000; Ginsberg, 1999; NIH, 2002; Malloy & Kane, 2001;). Furthermore, this independent relationship suggests some triglyceride-rich lipoproteins are atherogenic (Cullen 2000; NIH, 2002), meaning VLDL levels may prove to be a significant risk factor in the future. With hypertriglyceridemia, triglycerides are transferred from VLDL and chylomicrons (cholesterol molecules formed from dietary substrates) to LDL, leading primarily to small dense LDL particles and more CAD (Tulenko & Sumner, 2002).

Triglycerides should be measured after fasting as non-fasting triglyceride and other postprandial measurements are difficult to homogenize and arduous to perform (Sullivan, 2002). Finally, the authors of the ATP-III report set the classification of triglyceride in the following categories: Normal (<150 mg/dL), borderline high (150-199 mg/dL), high (200-499mg/dL), and very high (≥500mg/dL). Chylomicrons are very similar in their structure to VLDL, but are released by the intestinal mucosa cells directly after consuming fat (Tulenka & Sumner, 2002). They are less dense due to their large size (100-500nm) and the amount of triglyceride that is transported in them. Chylomicrons are found in the blood and lymphatic fluid where they serve to transport fat from its port of entry in the intestine to the liver and to adipose tissue. They travel via the lymphatic system and their large size renders penetration of the endothelium improbable. Though chylomicrons are large and rich in triglyceride, they contain only a relatively small amount of protein (Hertz, 1999; Schumaker &, Lambertas, 1992). Once chylomicrons enter the blood. they acquire ApoE and ApoC-II. They gradually reduce in size by lipoprotein lipase which removes free-fatty acids from the triglyceride pool in the cell. Chylomicron remnants are reassembled with endogenous triglyceride and cholesterol esters to form VLDLs (Tulenka & Sumner, 2002). Partially degraded chylomicrons, called chylomicron remnants, probably carry some atherogenic potential (NIH, 2002). The ATP-III does not report guidelines for chylomicron levels. Recently, investigators from the INTERHEART study have demonstrated abnormal lipid levels, when combined with smoking, provide over 90% of the risk associated with CAD (Yusef et al., 2004) and can be generalized globally. The authors of the study suggest that the ApoB/ApoA1 ratio was the most important risk factor for CAD. Previous research suggests that ApoB/ApoA1 has not warranted as much attention of other subfractions of cholesterol and therefore needs further study (Sullivan, 2002). The relative lack of familiarity among professionals regarding the importance of ApoB and ApoA1 levels has been a primary cause of ApoB measurement not prevailing over cholesterol levels as the basis for treatment guidelines. Finally, Sullivan (2002) suggests the stage has not been reached where ApoA1 levels can supersede HDL levels as the basis for treatment guidelines (Sullivan, 2002). INTERHEART is a landmark study that will likely reveal a greater role of the ApoB/ApoA1 ratio in the progression of CAD.

Research scientists have also demonstrated that HDL has at least three distinct subclasses based on particle size. Different subclasses include nascent HDL, HDL2, and HDL3 with nascent HDL being the smaller and more dense followed by HDL3 and HDL2. One study found gender differences were most pronounced for large HDL, with women having a twofold higher (8 vs. 4 micromole/L) concentration of large HDL particles than men. Additionally, the observed differences in males and females large HDL particle size also decreased with age (Freedman et al., 2004). The authors of a similar study found that the antioxidative activity of large HDL was significantly higher than that of small HDL (Kontush, Chantepie, & Chapman, 2003). Numerous small studies suggest greater predictive power for each of the HDL components including the observation that large HDL particles are more cardioprotective. All subclasses of HDL have been demonstrated to have a role in reverse cholesterol transport, but HDL2 seems to have the most protective effect, with recent evidence suggesting that HDL3 may play a role in LDL oxidation that is just as vital (Yoshikawa, Sakuma, Hibino, Sato, & Fujinami, 1997). Finally HDL seems to have an antioxidant, anti-inflammatory, anti-adhesive, anti-aggregatory, and profibinolytic effect that aids in the control of CAD beyond reverse cholesterol transport mechanisms (Tulenko & Sumner, 2002).

The ATP-III recommended ranges for HDL are low (<40 mg/dL) and high (>60 mg/dL). This is a significant change as previous reports also set recommended levels for HDL, but the low designation was set at less than 35 mg/dL (NIH, 2002). Additionally, the third report has removed specific HDL levels for men and women, and made one recommendation of greater than 50 mg/dL.

Another subclass of lipoprotein is VLDL which can be divided into VLDL1 (large and less dense), VLDL2 (smaller and more dense), and VLDL3 (smallest and most dense). Hypertriglyceridemia is associated with an excess of VLDL1 while hypercholesterolemia is associated with excess VLDL2. VLDL is triglyceride rich and contains C-II, ApoE, and ApoB-100. Lipoprotein lipase reduces the size of VLDL through the release of triglyceride creating a smaller, dense and more cholesterol rich lipoprotein. About two-thirds of VLDL passes down the lipoprotein metabolism cascade terminating as LDL (Tulenka & Sumner, 2002). VLDL1 is a key component is what has been called the atherogenic lipoprotein profile, which when combined with small dense LDL, and low HDL, it is theorized to be a significant lipid risk factor for CAD (Austin et al., 1988). Most triglycerides are consumed from food, but during times of decreased caloric intake, the liver produces triglyceride endogenously (Kwiterovich, 1989). The ATP-III reports that VLDL levels should be less than 31 mg/dL.

Previous studies have identified a LDL cholesterol “disconnect” between LDL concentration and the number or size of LDL particles among patients with low levels of LDL cholesterol (Otvos, Jeyarajah, & Cromwell, 2002). The term disconnect suggests a differing risk profile depending on the type of LDL cholesterol measure that is used. Typically many individuals who are considered to have normal levels of LDL cholesterol will screen abnormal using phenotype designation. This difference, or disconnect, may help to explain why myocardial infarction can occur in some people who have normal cholesterol and/or LDL levels. Furthermore, since cholesterol is carried via lipoproteins within the blood in spherical particles, between any two individuals there can be tremendous differences in both the number, size and composition of these particles (Garvey 2003; Tulenko & Sumner, 2002). The implication of this disconnect is that CAD risk between two patients with identical LDL particle number and particle size would be the same, despite differing LDL concentration values (Garvey, 2003; Otvos et al., 2002; Tulenko & Sumner, 2002).

The ATP-III (NCEP) report establishes the following ranges for LDL cholesterol levels: optimal (<100mg/dL), near optimal/above optimal (100-129 mg/dL), borderline high (130-159 mg/dL), high (160-189 mg/dL), and very high (≥190 mg/dL) (NIH, 2002). When risk is very high (two or more additional risk factors of existing heart disease), an LDL goal of <70 mg/dL is a therapeutic option, but lifestyle changes should still be pursued. This therapeutic option extends also to patients at very high risk who have a baseline LDL <100 mg/dL (Grundy et al., 2004). The metabolic balance of lipoproteins which is both vital and dangerous also uses reverse cholesterol transport to lower cholesterol in the periphery (Trigatti, 2005). HDL is synthesized by intestinal mucosal cells and the liver. It contains a small amount of phospholipids and ApoA1 (Tulenko & Sumner, 2002). Research has consistently identified an inverse relationship between HDL levels and CAD incidence. The mechanism for this relationship is still unclear, leading some researchers to suggest that low HDL levels are simply a marker for other lipid abnormalities. While the role of decreased HDL levels in atherosclerosis is still vague, it is considered an independent risk factor for CAD (NIH, 2002). It also has been identified as the greatest predictor, along with ApoA1 as the most important risk factor in patients with existing CAD (Bolibar, von Eckardstein, Assman, &Thompson, 2000; Devroey, 2004). HDL absorbs cholesterol in peripheral cells which enter the core of the cell through the action of lecithin-cholesterol acyltransferase. Inclusion of HDL in risk assessment can greatly enhance risk stratification (Kannel & Wilson, 1992).

LDL ranges in size from the largest and least dense (LDL1), intermediate density and size (LDL2) to the smallest and most dense (LDL3). The ATP-III report states that small LDL particles are formed in large part, although not exclusively, as a response to elevation of triglycerides via the production of very-low density lipoproteins (VLDL) and specifically VLDL1 (Malloy & Kane, 2001; NIH, 2002).

The presence of small, dense LDL particles is associated with more than a three-fold increase in the risk of CAD and is independent of LDL levels (Austin, Breslow, Hennekens, Buring, Willett, & Kraus, 1988). Tulenka & Sumner (2002) further suggest that not all LDL particles are the same and that variations in disease outcomes may by attributable to differences in particle size and number even when LDL levels are the same between patients. The authors of the Physicians Health Study demonstrated that each decrease of eight angstroms in LDL peak particle size was associated with a significant 38% increase in the seven-year risk of myocardial infarction after adjustment for age and smoking status (Lemarche, Lemieux, & Depres, 1999).

The correlation between particle size and CAD may exist because of the physiological properties of smaller particles. Researchers suggests smaller and denser LDL particles are more susceptible to in vitro oxidation and have been shown to be degraded less rapidly (Hsueh & Law, 1998). In addition, smaller particles diffuse more easily into the sub-endothelial space in the periphery. A stronger diffusion gradient would push more particles into the arterial wall, attract more macrophages, and develop more foam cells.

Using gel electrophoresis, previous studies have computed and investigated both LDL peak particle size and the mean LDL particle size (Hsueh & Law, 1998). Mean LDL particle size is determined by computing the relative abundance of each of the LDL subclasses within one individual through a densitometric scan (Hsueh & Law, 1998; Lemarche et al., 1999). The results of these studies have led to the development of two different categories of LDL classification that rely on both peak particle size and LDL subclass distribution (Tulenko & Sumner, 2002). These two designations are Phenotype A and Phenotype B. Phenotype A consists of a predominance of LDL particles of >25.5 nanometers and Phenotype B is defined as the predominance of small LDL particles with diameters However, Cromwell and Otvos (2004) believe it is not clear that small LDL particles are more atherogenic than large ones simply because individuals with small LDL particles also have a higher LDL particle number. The authors further state that LDL particle number measured by nuclear magnetic resonance has consistently been shown to be a strong, independent predictor of CAD. In other words, small dense particles may have been found to be more atherogenic due to a higher number of particles that are typically associated with small dense particles. Also, the combination of the two (high particle number, and small dense particles) may place individuals at more risk than either risk factor alone.

Historically, total cholesterol concentration was used to assess an individual’s risk of CAD (Bowden & Kingery, 2004). Because cholesterol contributes to the buildup of atherosclerotic plaques, an individual’s blood cholesterol concentration could be a way to measure risk for heart disease. Clinical studies are consistent in supporting the projection that for serum cholesterol levels in the 250-300 mg/dl range, each 1% reduction in serum cholesterol level reduces CAD rates by approximately 2% (NIH, 1989a). However, the degree of stenosis and CAD varies between individuals with the same total cholesterol and other lipid levels (Bowden, Kingery, Rust, 2004, Kmietowicz, 1998; Telenko & Sumner, 2002).

Total cholesterol tends to reflect average dietary habits that affect LDL, and can reasonably provide an assessment of CVD risk between participants. Yet, the differences in risk between individuals can be strongly influenced by many additional factors. Therefore the measurement of total cholesterol alone cannot adequately reflect individual risk of CAD (NIH, 2002) and should rarely be used as the sole lipid measure in cholesterol screenings. Other studies have also demonstrated the process of heart disease to consist of many factors that are independent of total cholesterol (Katerndahl & Lawler, 1999). These other risk factors fall into two three broad categories, consisting of blood markers, behavior, and biology. New blood tests that identify increased cardiovascular risk include various subfractions of cholesterol. Many of these new markers relate to the physiological functions of cholesterol and the interaction between these markers and the cholesterol in the periphery.

The generally accepted ranges for total cholesterol levels (NIH, 2002) consist of desirable (<200mg/dL), borderline high (200-239mg/dL), and high (≥240mg/dL). If a patient’s cholesterol level is in the high category, a LDL cholesterol measure should be performed. If the patient is in the borderline high range, another total cholesterol measurement should be taken within eight weeks and the average of the two readings used to guide future decisions (NIH, 2002).

Cholesterol Subfractions
LDL cholesterol accounts for 60-75% of the total serum cholesterol and is the terminal end of in the pathway of lipoprotein metabolism called cholesterol transport. Numerous epidemio-logical, physiological, and animal models have linked high LDL levels to CAD (American Heart Association, 2004; Assman, Cullen & Schulte, 1998; NIH, 1989a; Smith et al., 2004; Stone, 2005). High levels of LDL cholesterol are able to penetrate the porous endothelium of arteries and begin to accumulate if plasma concentrations are abnormal. This natural plaque is eventually converted to unstable plaque increasing the likelihood of rupture and possible thrombosis (NIH, 2002). Accordingly, the greatest absolute diminution of risk can be achieved by the reduction of LDL which may directly lower platelet aggregation, vascular reactivity, and lower cytokine release leading to a further reduction in risk for myocardial infarction (Sullivan, 2002). In fact, when elevated LDL levels are combined with comorbidity factors of smoking and hypertension, this complex explains over 90% of myocardial infarction cases occurring in middle age (Wilhelmsen, 1997). The landmark INTERHEART data suggests that 90% of risk comes from combination of abnormal levels of apolipoproteins found in LDL and smoking. LDL contains ApoB-100 which has been linked to atherogenesis (Yusef, Hawken, Ounpuu, Dans, Avesum, Lanas et al., 2004).

Finally, it should be noted that although LDL lowering therapy is believe to offer the greatest benefit for CAD risk reduction, LDL alone is insufficient to predict CAD incidence and risk stratification. The best risk prediction strategy requires measurement of other cholesterol components and particle size and concentration (Wald, Law, Watt, Wu et al., 1994).