Metabolic syndrome is a common and complex disorder combining obesity, dyslipidemia, hypertension, and insulin resistance. People with metabolic syndrome are at considerable increased risk of developing coronary artery disease and type 2 diabetes. It affects one in five people, and increases with age. Several studies estimate the prevalence in the United States to be approximately 25% of the population.
Coronary artery disease is the leading cause of death in diabetic patients and circulating levels of oxidized LDL are usually elevated in untreated diabetic patients with documented coronary artery disease. Most important, diabetic patients with coronary artery disease and elevated oxidized LDL levels are usually able to significantly lower their oxidized LDL levels with statin therapy, and, at the same time, can often ameliorate their signs/symptoms of coronary artery disease. It is especially noteworthy that oxidized LDL levels have greater diagnostic accuracy than native LDL levels in identifying patients with clinical coronary artery disease (2006 American Journal of Cardiology paper of Nina Johnston). Interestingly, lowering elevated oxidized LDL levels in diabetic patients is not an option but a necessity, according to many physicians who have been ordering oxidized LDL levels on their patients at Shiel Medical Laboratories.
The following highlights are presented in the attached articles:
Holvoet et al (1) measured oxidized LDL in 1,899 generally healthy people aged 35-45 in a prospective study of “Coronary Artery Risk Development In Young Adults (CARDIA)”. After five years of follow up evaluation, patients with elevated levels of oxidized LDL had 3.5 times the risk of developing metabolic syndrome. Co-author Dr. David Jacobs stated that these findings are especially important for the prevention of heart disease and diabetes since the participants are relatively young and free of symptoms.
Clinically identified type 2 diabetes is preceded by a long period of insulin resistance, during which blood glucose is maintained at normal levels by compensatory hyperinsulinemia. It is noteworthy that increased levels of oxidized LDL appear to be a deleterious factor leading to beta cell damage, insulin resistance, impaired glucose tolerance, and ultimately to type 2 diabetes.
Kelly et al (2) found that oxidized LDL is significantly associated with adiposity and with insulin resistance in children indicating that oxidative stress may be independently related to the development of insulin resistance early in life, especially in obese youth.
Park et al (3) show a strong association of increased oxidized LDL levels with insulin resistance, independent of obesity. It is noteworthy that more and more articles are referencing the affects of oxidative stress to damaged DNA, lipids, proteins, and other molecules which may contribute to the development and progression of chronic disease, including cardiovascular disease, kidney failure, physical activity, aging, and cancer.
Holvoet et al (4) define the association between metabolic syndrome and oxidized LDL, and the mechanisms underlying the relationship of key elements.
1. Holvoet et al, Association Between Circulating Low Density Lipoprotein and Incidence of Metabolic Syndrome. JAMA, May 21, 2008:299. 2287 – 2293
2. Kelly et al, Relation of circulating Oxidized LDL to Obesity and Insulin in Children. Pediatric Diabetes, 2010: 10.1111
3. Park et al, Oxidative Stress and Insulin Resistance. 2009
4. Holvoet et al, oxidized LDL and the Metabolic Syndrome. Future Lipidol, 2008: 3(6) 637-649