This study shows a relatively high percentage of hypercholesterolemia among young university students. A higher frequency of PHC was observed in males than in females, a consensus accepted in the scientific community.31
Using the formula provided by the National Institutes of Health (NIH, USA),32
the data from the current study may be used to calculate the risk factor of developing a CHD event in the next ten years among the study participants. The presence of family history of CHD in students with high risk indicates the possibility of having a genetic element in CHD. Obesity also contributed to the risk of CHD in five students (3%). Although controversial, factors causing PHC can be controlled by lifestyle modifications, genetic counseling and administration of drugs such as statins.1,33
For adolescents and young adults at low risk, lipid profile testing is not ordered routinely. Also, there is no consensus among experts in the field for the definition of hypercholesterolemia. However, the American National Heart, Lung, and Blood Institute and the National Cholesterol Education Program define HC according to CHD risk factors score of each of individual.7
Thus, for individuals with 0-1 risk factors (as with the current study participants), normal LDLC would be ≤4.2 mmol/L; TC would be ≤5.1 mmol/L and TC/HDLC ≤4. The three guidelines are combined in a Venn diagram as shown in . Ten students (nine females and one male) among the studied group exhibited high or very high levels in all three critria.
Figure 4 Venn diagram summarizing the three criteria used to define hypercholesterolemia in individuals with no CHD risk factors. The red circle represents students with total cholesterol TC ≥5.1 mmol/L, the black circle represents students with LDL ≥3.4 (more ...)
According to WHO, HC is a global health problem that has to be monitored and controlled. However, very few studies address this issue in our area.1
The Bahrain Ministry of Health reported that more than 60% of Bahrainis over 19 years of age are either obese or overweight, and CHD is the main cause of death (40%) among Bahrainis.34
Additionally, the Clinical Chemistry Laboratory at Salmaniya Medical Complex receives around 5000 lipid profile samples monthly from all satellite centers in the country, 25% of which are hypercholesterolemic (Dr. Das, personal communications).
Hypercholesterolemia by itself is not a disease, but it is a metabolic imbalance that contributes to several diseases mainly CHD. Excess circulating cholesterol and low density lipoprotein (LDL) damage the endothelium of the coronary artery and promote inflammation culminating in restriction of the coronary artery and plaque rupture. On the other hand, substantial evidence supports the role of inflammation in atherogenesis where more than 50% of heart attacks and strokes occur among individuals with normal or low blood cholesterol. Thus, inflammation markers such as hsCRP, proinflammatory cytokines, acute phase reactants and others should be considered in determining the risk of CHD.22,35
Young people with a high cholesterol levels are more likely to be unaware of this elevation because they have not been tested and are more likely to ignore it since they are not experiencing symptoms. Acquired HC due to high fat diet, primarily saturated fats, coupled with inactive lifestyle can be reversed by modifying both. Indeed, several studies consider HDL an atheroprotective molecule due to its anti-inflammatory effects.35
The majority of PHC is due to inactivity and unhealthy diet. Though generally, the contribution of defective genes involved in the metabolism of lipids plays a minor role in causing acquired HC.36
However, sometimes the contribution of genetics in PHC could be significant where founder mutations are present.37
Recently, we discovered a founder mutation in the gene coding for low density lipoprotein receptor (LDLR) in two unrelated Arab families that descended from Adnan and Qahtan, the fathers of Arabs.38
Alternatively, elevated blood lipid levels could be associated with genetic variations (SNPs) in different loci.39,40
Pletcher et al. 2010, reported that non-optimal levels of LDL (high) and HDL (low) cholesterol during young adulthood are independently associated with CHD two decades later. Thus, cholesterol screening is recommended by the age of 20 for overweight young adults and those with family history of CHD.41,42
The greatest challenge for the public health workers is to assess the prevalence of PHC and reduce the cost of this asymptomatic disorder through signaling on modifiable and non-modifiable risk factors. The burden of these diseases is not limited to claiming lives, but also to escalating costs of health care. About 17% of American adults have high blood cholesterol. The associated direct and indirect costs of CHD in the United States are between $300-$500 billion annually (AHA, 2010).26
Among the limitations of this study is the sample gender composition; however, this is close to the institution’s student composition, where female students represent 70%. However, the number of students (166) was statistically significant for 95% confidence coefficient and a precision value of 0.03. Irrespective of the interpretations, more studies are needed in the area of epidemiology to establish the prevalence of HC among the entire population and not only young healthy individuals.