Familial hypercholesterolemia 1 (FHCL1) is an autosomal dominant disorder characterized by markedly elevated levels of serum cholesterol bound to low density lipoprotein (LDL), resulting in hypercholesterolemia, xanthomas, and atherosclerosis of coronary arteries. FHCL1 is associated with mutations in the low density lipoprotein receptor gene, LDLR, which is a cell surface receptor that plays an important role in cholesterol homeostasis. Single nucleotide polymorphisms in other genes such as the APOA2 gene, EPHX2 gene, and GHR gene are known to act as modifiers of the FHCL1 phenotype.
Al-Mahroos and McKeigue (1998) studied the prevalence of diabetes and associated risk factors in the population of Bahrain. in 2,128 Bahrainis aged 40-69 years. Age-standardized prevalence of diabetes was 25% in Jaafari Arabs, 48% in Sunni Arabs, and 23% in Iranians. Mean plasma cholesterol was 0.5 mmol/l higher in diabetic than in normoglycemic participants, 0.5 mmol/l higher in Sunni than in Jaafari Arabs, and, excluding diabetic individuals, 0.2 mmol/l higher in those with a positive family history of diabetes than in those with a negative family history. The authors concluded that the high rates of diabetes in Bahrain and other Arabian Peninsula populations appear to be part of a familial syndrome that includes raised plasma cholesterol levels. Risk is related to ethnic origin but not to parental consanguinity.
Shawar et al. (2012b) studied the prevalence of hypercholesterolemia among 166 apparently healthy non-smoker university students (aged between 16-30 years) in Bahrain. The population consisted of 85 Saudis and 81 Bahrainis. A total of 44 students (19 males, 25 females) were found to have hypercholesterolemia. Eight of these students reported a family history of cardiac events, while five of them were obese with a BMI >30.
Olusi et al. (1997) carried out a study on a hospital outpatient population of 1076 subjects with a mean age of 38.9 years and a male to female ratio close to one, to determine the prevalence of hypercholesterolemia in Kuwait. The prevalence of hypercholesterolemia was found to constitute 15.8% of the cohort, 16% in males, and 15.7% in females. Moreover, the prevalence of hypercholesterolemia in middle-aged (40-49 years) Kuwaiti males was found to comprise 22.2% of the cohort proposing an increased risk of coronary heart disease in one of every five Kuwaiti middle-aged males. Furthermore, Olusi et al. found an extremely high prevalence rate (43.2%) of hypercholesterolemia in females aged 50-59 years and 31.2% in females aged 60-69 years.
Selvan et al. (2007) described the clinical features and family history of an 11-year old Kuwaiti boy with homozygous familial hypercholesterolemia. The patient presented with a history of recurrent episodes of chest pain and multiple xanthomas. Upon examination, he was found to have clinical features of moderate aortic stenosis and aortic regurgitation. ECG showed ST depression in the anterior and inferior leads, and thickened aortic valve with moderate regurgitation. Angiogram showed 70% stenosis of the left main coronary artery and ostial stenosis of the right coronary artery. Lipid profile was grossly abnormal. Pedigree analysis of his family revealed an interesting history. Both this father and paternal grandmother, who died at the age of 50-years following a myocardial infarction, were hypercholesterolemic. Of his siblings, two of either sex, had died after suffering from recurrent chest pain and multiple xanthomas, while three others had multiple xanthomas and hypercholesterolemia and were under treatment. Two other siblings were normal. The patient was managed with beta-receptor agonists, vasodilators, anti-thrombotics, cholesterol lowering drugs, and analgesics. However, he succumbed on the fourth day to severe coronary heart disease, emphasizing the need for early diagnosis of familial cases of hypercholesterolemia.
Edwards et al. (1978) studied fasting serum cholesterol and triglyceride levels in 131 randomly selected adult members of a Lebanese Community of Western New York. Mean cholesterol levels (males, 217 mg%; females 234 mg%) were higher than those reported from the Lebanon but similar to those reported in most other populations. Mean triglyceride levels (males, 153 mg%; females, 115 mg%) were higher than those reported in most other populations. Twenty-three subjects were hyperlipidemic on the basis of age and frequency distribution adjusted serum lipid levels above the 90th percentile. Clinical and family studies carried out on 13 of these 23 hyperlipidemic subjects suggested that 77% had monogenic hyperlipidemia and 23% primary non-monogenic hyperlipidemia. A high frequency of familial hypercholesterolemia (minimum estimate 0.7%) was found, in keeping with the high frequency of the disorder in Lebanon.
Agarwal et al. (1995) conducted a study to determine if elevated cholesterol is a problem in the United Arab Emirates in order to be able to evaluate the contribution of cholesterol as a risk factor for atherosclerosis in this environment. In 834 patients, there were 19 nationalities represented which were pooled into 7 groups (5 Arab and 2 non Arab) according to their ethnic origins. The prevalence of hypercholesterolemia varied from 47.2-53% in the Arab Nationals. The mean cholesterol levels of the Arab subgroups were similar and showed no difference, statistically. Similarly, within the Arab subgroups, the median cholesterol levels were no different.