Metabolic syndrome

The metabolic syndrome ( sometimes referred to as deadly quartet, Reavan syndrome or syndrome X) is now regarded as the key risk factor for coronary heart disease. It is characterized by these four factors: abdominal obesity, high blood pressure ( hypertension), abnormal blood lipid levels ( dyslipidemia ) and insulin resistance. The disease develops from a lifestyle that is characterized by constant overeating and lack of exercise, and affects a high proportion of people living in industrialized countries population.

The definition of the metabolic syndrome is repeatedly changed in the last years. A generally accepted definition does not yet exist. The classification is based mostly on either the insulin resistance ( insulin resistance syndrome, WHO classification 1999) or lifestyle ( NCEP - ATP III). There is a globally valid ICD -10 code does not, in Germany the DIMDI Thesaurus enables the collection with the code E.88.9 " metabolic disorder, unspecified ". Since under the German Kodierrichtlinie (DKR ) D004d no specific code within the ICD-10 catalog is available, the individual manifestations are to encrypt within the G -DRG system.

Usually the treatment is directed to the treatment of insulin resistance or obesity.

Pathophysiology

The metabolic syndrome is primarily a disease of developed countries and developed from a Western lifestyle, characterized by hypercaloric nutrition and lack of physical exercise. By doing so the obesity leads to insulin resistance. The pancreas is not able to produce enough insulin to the body. This hormone is mainly responsible for blood sugar levels and ensures that both muscle and adipose tissue can absorb the glucose present means of GLUT -4 transporters. An oversupply of glucose in the blood the pancreas temporarily by an increased insulin production to compensate ( hyperinsulinemia ) with the aim to maintain a euglycemic metabolic state. The high insulin levels lead but with time to a loss of efficacy of the hormone and it develops a resistance to insulin, which may progress to type 2 diabetes.

Significant influence on the development of the metabolic syndrome has the visceral adipose tissue. There is adipocyte (fat cells), which are located between the organs of the abdominal cavity ( intra-abdominal ). Those adipocytes are hormonally active and are subjected to increased lipolysis, which is no longer responsive to the inhibitory effect of insulin. Substances secreted include TNF- α and interleukin -6 ( inflammatory mediators which inter alia promote insulin resistance). At the same time the concentration of adiponectin, a hormone produced by adipocytes that acts insulin sensitive, anti - atherogenic and anti -inflammatory drops. The increased release of nonesterified fatty acids by these adipocytes inhibit the action of insulin on the liver, as well as the muscles. This glycogenolysis and gluconeogenesis in the liver will be facilitated and there is increased release of glucose from the liver.

At the same time it comes to atherogenic dyslipidemia, a specific change in blood lipid levels characterized by low HDL levels and high levels of triglycerides and small, dense LDL particles. By the effect of free fatty acids increases in the liver, the VLDL production. These lipoproteins are characterized by a high concentration of triglycerides, which thus reach the periphery. VLDL particles are metabolized within the lipid metabolism with the elimination of fatty acids by lipoprotein lipase to IDL and LDL. In this case, these lipoproteins interact with HDL particles and exchange over the cholesterol ester transfer protein ( CETP) triglycerides, cholesterol esters from against. Thus, the Cholesterolanteil decreases in HDL molecules and their concentration decreases. The LDL particle composition also changed due to a decrease in the Cholesterolanteile within the lipoproteins. The resulting small dense LDL molecules are atherogenic.

Diagnostics

WHO criteria

According to the WHO criteria of 1998, metabolic syndrome is present if the following risk factors:

And two of the following parameters:

• Arterial hypertension, ie blood pressure ≥ 140/90 mmHg
• Dyslipidemia: triglycerides > 1.695 mmol / l and HDL ≤ 0.9 mmol / l ( men) or ≤ 1.0 mmol / l (women )
• Visceral obesity: waist - to-hip ratio of > 0.9 ( men) or> 0.85 ( for women) and / or a BMI > 30 kg / m²

The criteria for the metabolic syndrome have evolved since the original definition by WHO through better clinical evidence and the analysis by various consensus conferences and professional organizations:

Criteria of the IDF (2005)

Frequently used and recognized internationally is the definition of " International Diabetes Foundation " (IDF ).

Requirement for the presence of metabolic syndrome is the presence of a belly stressed ( so-called central ) obesity: waist circumference ≥ In men, a 94 cm, ≥ 80 cm in women ( people of European descent, Asians other values ​​apply ).

Come to this guiding factor at least two of the risk factors

• Fasting blood glucose levels of> 100 mg / dl or diagnosed diabetes mellitus,
• Elevated triglycerides > 150 mg / dl or already initiated therapy for lowering triglycerides,
• Low HDL cholesterol: <40 mg / dl in men and < 50 mg / dl in women or already initiated therapy to increase HDL
• High blood pressure ( from> 130 mmHg systolic or> 85 mmHg diastolic) or already treated hypertension

Addition, there is a significantly higher risk of suffering a cardiovascular disease later in life. In this case, the so-called " metabolic syndrome " before. The risk factors of obesity, diabetes, dyslipidemia and hypertension are for this reason called in professional circles cardiometabolic risk factors.

Criteria according to NCEP - ATP III (2001)

According to the " National Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults " ( NCEP - ATP III) metabolic syndrome, the diagnosis is made if at least three of the following five criteria are met:

• Abdominal fat distribution, determined by a waist circumference of more than 102 cm in men or 88 cm in women,
• Serum triglycerides above 150 mg / dl,
• HDL cholesterol below 40 mg / dl in men and < 50 mg / dl in women,
• Blood pressure of 130/ 85 mmHg or more,
• Fasting blood sugar of over 110 mg / dl ( or presence of type 2 diabetes ).

Waist circumference as a criterion

Plays a major role in the definition of metabolic syndrome, as already indicated above, an increased waist circumference. Because cardiovascular risk is less the extent of excess weight rather than the fat distribution pattern crucial: especially disadvantageous effect here fat deposits from the abdomen and the internal organs. This deep abdominal fat - Experts call it " intra-abdominal fat " or " visceral fat " - is very metabolically active. It affects the fat and carbohydrate metabolism ( glucose metabolism ) so that lipid disorders and diabetes can be the result.

A measurement of the waist circumference at the waist is considered to be easier and faster way to make an initial risk assessment. An increased risk is, according to ATP III before for women over 88 cm. In men, the risk area of 102 cm begins. In Germany, about 30-40 % exceed this risk threshold. By the reduction of the abdominal girth, for example by sport, the risk of cardiovascular disease can be greatly reduced.

Importance of symptoms

Insulin resistance, obesity, hypertension and dyslipidemia also occur independently of each other and each represents for increased risk for the later occurrence of coronary heart disease and atherosclerosis

Therapy

After diagnosis a change of lifestyle should be performed. The aim is to reduce the body weight or waist circumference, reduce blood fat and postpone the possible occurrence of diabetes mellitus as far as possible. Recommended this, especially regular physical activity ( eg 30 minutes per day, at least three times a week, but at least daily noticeable increase in activity).

To normalize the body weight on the diet, there are several recommendations: DGE recommends slowly digestible carbohydrates as largest nutritional ingredient and a reduction in the levels of fat (carbohydrates 50 to 60 % of the total diet / fat: 20-25 % / protein = rest about 15 to 20 % ). However, there are also studies that look at a greater effectiveness in symptom improvement of the metabolic syndrome with the reduction of carbohydrate moieties in the diet.

If a diabetes mellitus before, he should be treated medically with insufficient effect of diet and exercise therapy. The same applies to the setting of hypertension.

An increase in the vitamin D levels could possibly be helpful. A meta-analysis of 100,000 patients showed that the metabolic syndrome is only half as often as in participants occurred in subjects with high vitamin D levels with low levels of vitamin D in the blood.