Dyslipidemia

Metabolic syndrome has been proposed to indicate individuals in whom the coexistence of three or more factors with obesity or insulin resistance precipitates ischemic cardiac disease, although each individual risk factor is not severe when taken into consideration separately. Reaven used the term 'syndrome X' to indicate cases in whom hyperinsulinemia, IGT, low blood HDL(high-density lipoprotein)-cholesterol level, high blood VLDL(very low density lipoprotein) triglyceride level, and hypertension are all present. Visceral fat syndrome caused by accumulation of visceral fat has also been proposed. These conditions are accompanied by certain concomitant risk factors such as obesity, hypenutrition, insufficient exercise, and genetic predisposition, and are related to insulin resistance. A decrease in triglyceride degradation by lipoprotein lipase due to insulin resistance leads to an increase in remnant particles and a decrease in HDL.     

Dyslipidemia and atherosclerosis

Dyslipidemia is the most important risk factor for atherosclerosis. LDL, VLDL remnants, chylomicron remnants, small dense LDL(sdLDL), Lp(a), and oxidized LDL are pro-atherogenic and HDLs are anti-atherogenic lipoproteins. Not native LDL but modified LDL causes to the formation of foam cells. Among LDL particles, smaller denser LDLs are more susceptible to oxidation, and have longer residence time and higher affinity to the extracellular matrix. Delayed clearance of triglyceride-rich lipoproteins results in the formation of sdLDL which is associated with insulin resistance and postprandial hyperlipidemia. HDL plays an important role in the reverse cholesterol transport as well as having antiinflammatory and antioxidative effects. Dysfunction of HDL is an independent pro-atherogenic factor. In addition, decreased HDL-cholesterol is a feature of the metabolic dyslipidemia.     

Dyslipidemia in HIV patients

Thanks to antiretroviral therapy, people with human immunodeficiency virus (HIV) infection are living longer, but as they do, non-HIV medical problems become more relevant. In particular, dyslipidemia, an important reversible risk factor for cardiovascular disease, has been linked to HIV infection and its treatment. Although controversy remains as to whether people with HIV infections will develop premature coronary heart disease, it seems prudent to manage dyslipidemia in these patients just as we do in our HIV-negative patients. Interactions between lipid-lowering drugs and antiretroviral drugs require special attention.     

Dyslipidemia in metabolic syndrome

The prevalence of obesity has become increasingly common worldwide, in particular western countries. Obesity, together with insulin resistance, leads to metabolic syndrome in which other coronary risk factors including hyperlipidemia and hypertension cluster in one individual. Hyperlipidemia in metabolic syndrome is characterized increased triglyceride(TG), decreased HDL-C, and small dense LDL, called dyslipidemic triad. Dyslipidemia is attributable to increased flux of free fatty acids to the liver, which promotes TG synthesis, thus VLDL production. Increased VLDL, together with decreased lipoprotein lipase activity due to insulin resistance, causes accumulation of TG-rich lipoproteins, including proatherogenic remnants. Further, increased activities of cholesteryl ester transfer protein and hepatic triglyceride lipase results in low HDL-C and small dense LDL. Initial treatment should be directed to modify life style(weight loss and increased physical activity). Then, pharmacological intervention should be considered when the initial treatment is not fully successful. Fibrate derivatives are considered to be ideal to correct dyslipidemic triad. In addition, potent statins(HMG-CoA reductase inhibitor) can be alternative in metabolic syndrome subjects with elevated LDL-C levels.     

Dyslipidemia in the critically ill

Total and HDL cholesterol levels fall at the onset of acute illness and the cholesterol levels normalize as the patient recovers. Hypocholesterolemia may predispose the critically ill patient to sepsis and adrenal failure. Early enteral nutrition and tight glycemic control accelerate the recovery of the cholesterol levels.     

Pediatric Dyslipidemia and Screening Recommendations

Pediatric dyslipidemia affects approximately 20% of children ages 6 to 19 years. This disease is impacted by and contributes to many factors, including obesity, metabolic syndrome, diabetes, and hypothyroidism. Obesity doubles the risk of dyslipidemia, but 26% to 63% of normal-weight children have lipid abnormalities. Dyslipidemia contributes to pediatric onset of atherosclerotic changes, and early adult cardiovascular complications. Sedentary lifestyle and poor food choices are the primary causes, but familial hypercholesterolemia affects 1 in 200 to 500 individuals. Evidence-based guidelines and screening recommendations are inconsistent among disciplines, there is poor compliance with utilization, and treatment options lack long-term outcome data.     

New Directions in Managing Dyslipidemia

Statin therapy has long been the mainstay of dyslipidemia management due to superior reduction in morbidity and mortality from cardiovascular disease. However, many patients who take statins fail to meet low-density lipoprotein-cholesterol targets, have recurrent atherosclerotic cardiovascular disease, or are statin intolerant. Recent updates give guidance on prevention of atherosclerotic cardiovascular disease in all patients, including those for whom statin therapy is contraindicated or insufficient. Other classes of medications, such as ezetimibe and proprotein convertase subtilisin/kexin type 9 inhibitors, can lower low-density lipoprotein cholesterol and may also improve cardiovascular outcomes. This report explores dyslipidemia management guidelines, reviews the use of ezetimibe and proprotein convertase subtilisin/kexin type 9 inhibitors, and provides recommendations for nurse practitioners.     

Dyslipidemia in type 2 diabetes

Type 2 diabetes mellitus is associated with a cluster of lipid abnormalities:elevated plasma triglycerides, reduced high-density lipoprotein cholesterol, and smaller and denser low-density lipoproteins,which have been associated with an increased risk of cardiovascular disease. Insulin resistance may contribute to dyslipidemia associated with type 2 diabetes by increasing hepatic secretion of large,triglyceride-rich very low-density lipoprotein particles and by impairing the clearance of lipoprotein particles from plasma. Lifestyle interventions may be effective in improving the diabetic dyslipidemia syndrome. For patients who do not respond to lifestyle changes, pharmacologic therapies (lipid-lowering medications and anti-diabetic agents) are available. Clinical trials demonstrate that the use of such pharmaceutics to treat diabetic dyslipidemia concomitantly reduces the risk of coronary artery disease.     

从脾论治甲状腺功能减退症合并血脂异常

甲状腺功能减退症的患者因自身TSH水平升高,会影响机体的脂代谢,从而并发血脂异常.在影响患者日常生活的同时,也增加了心脑血管疾病的患病风险.人体在维持水液代谢和气血运行功能正常时,肝、脾、肾三脏的协同作用起关键作用.在整个疾病过程中,脾的功能失常贯穿始终,从脾论治是治疗甲状腺功能减退症合并血脂异常的重点.     

Dyslipidemia and oxidative stress in sarcoidosis patients

ObjectivesSarcoidosis is an inflammatory disease characterised by enhanced production of reactive oxygen species and alterations in the circulating lipid profile. Both attributes are thought to play a role in its pathogenesis. However, current knowledge regarding the significance of blood oxidative stress/anti-oxidant defence as well as alterations in lipid status parameters in sarcoidosis is scarce. The aim of our study was to assess these parameters and their inter-relationships, as well as their potential for patient-control discrimination.Design and methodsOxidative stress status and anti-oxidant defence parameters were determined in serum and erythrocytes and lipid status parameters were assessed in the serum of 213 treated sarcoidosis patients and 90 controls.ResultsMalondialdehyde, superoxide anion, total oxidant status, prooxidant–antioxidant balance and triglycerides were significantly higher whereas total anti-oxidant status, superoxide dismutase activity and HDL-cholesterol were significantly lower in sarcoidosis patients compared with controls. Total sulfhydryl group content was higher in patients compared with controls. Serum and erythrocyte malondialdehyde exhibited the strongest ability to predict disease presence. Elevated oxidative stress was characterised by higher clinical accuracy compared with lipid status abnormality. Some oxidative stress and lipid status markers were significantly associated in sarcoidosis.ConclusionsSarcoidosis is characterised by increased oxidative stress, diminished overall anti-oxidative protection and alterations in the circulating lipid profile. Both oxidative stress and lipid status parameters demonstrated the potential to discriminate sarcoidosis from controls which was particularly evident from the point of view of oxidative stress status parameters. Association between these parameters may indicate an increased risk for atherosclerosis development.     

血脂异常的运动疗法

临床研究和动物实验均证明，运动对血脂异常患者的血脂水平有肯定的改善作用，其机制与其直接调节脂质代谢、载脂蛋白、脂蛋白酶有关，也和调节胰岛素、黏附因子、细胞因子等发挥间接作用有关。血脂异常患者采用运动疗法应该注意选择合适的运动方式，持之以恒。运动强度对降脂效果无明显影响。     

Dyslipidemia and lipid-lowering therapy in the elderly

According to the current evidence, the fastest growing proportion of patient populations seeking healthcare is those over 65 years of age. Coronary artery disease and subclinical atherosclerosis are highly prevalent in this group of patients and are strongly linked to dyslipidemia, a well-established risk factor for atherosclerosis. Treating dyslipidemia in this group of patients requires specific knowledge and understanding of common dyslipidemias and the relative safety of various pharmacologic agents in the presence of possible multiple comorbidities. Lifestyle modification remains the first step in the treatment of dyslipidemia; however, it can be difficult to sustain and achieve acceptable compliance in the elderly and it is best used in combination with drug therapy. Statins are widely accepted as the first-line therapy. Several recent studies have demonstrated that statins are safe and effective in the elderly. However, it is important to note that there is very limited data regarding the effects of dyslipidemia treatment on morbidity and mortality in patients over 85 years of age. In summary, the clinicians must recognize that the presence of dyslipidemia in the elderly poses substantial risk of coronary events and stroke. The available evidence has demonstrated that in most elderly patients who are at increased risk for cardiovascular morbidity and mortality, treatment of dyslipidemia with appropriate therapy reduces the risk, and when used carefully with close monitoring for safety, the treatment is generally well tolerated. With increasing life expectancy, it is critical for physicians to recognize the importance of detection and treatment of dyslipidemia in the elderly.