Triglycerides

Hypertriglyceridemia refers to an elevated triglyceride content of the blood serum. Naturally occurring fats consist predominantly of triacylglycerols, which are also called triglycerides (TG) or neutral fats. In addition, there are small amounts of mono- and diacylglycerols. Triglycerides serve as energy stores. The nearly 12 kg of triglycerides that a normal-weight person stores in adipose tissue correspond to an energy supply of about 112,800 kcal. The triglycerides are esters of glycerol with 3 fatty acid residues, with oleic acid and palmitic acid being the main ones present in the human fat store. Triglycerides are thus a mixture of different triacylglycerols.Like cholesterol, triglycerides are bound to apolipoproteins in the plasma because of their difficult solubility in the aqueous environment and are thus transported. In this context, the so-called chylomicrons – exogenous triglycerides, that is, triglycerides taken in from outside with food – and the “Very Low Density Lipoproteins” (VLDL) – are rich in triglycerides.

The process

Triglyceride concentrations can be determined from your blood serum or plasma using a laboratory diagnostic test. Material needed

  • Blood serum, taken fasting in the morning [now only required in special cases]Note! Experience from Denmark, where laboratories have been accepting blood samples from postprandial (“after eating”) patients for lipid profile determination since 2009, confirms that patients no longer need to be fasting before blood sampling.Fasting values are now only indicated when
    • Triglycerides at baseline > 440 mg/dl (5 mmol/l).
    • Hypertriglyceridemia is known
    • Hypertriglyceridemia-associated pancreatitis (i.e., when patients have recovered from pancreatitis (inflammation of the pancreas))
      • Patients should receive medications,
        • Intended to lower triglyceride levels (determined before starting medication).
        • That may induce severe hypertriglyceridemia (determination before initiation of medication)

Preparation of the patient [special case, see above].

  • For blood collection, you must appear fasting – without having eaten anything for 12 hours.
  • You should not drink alcohol the night before the blood draw.
  • You must strictly adhere to these requirements, otherwise you will not get usable results through this examination.

Interfering factors

  • Extremely high triglyceride levels are measured when blood is drawn in a non-fasted state.
  • If alcohol is consumed the evening before the blood sample is taken, triglyceride levels may be greatly elevated.
  • Values may be distorted in the presence of existing fractures (broken bones).

Normal values for triglycerides

Adults 50 to 200 mg/dl (0.6 to 2.3 mmol/l)
Children up to 10 years 30 to 100 mg/dl (0.3 to 1.1 mmol/l)
Children up to 14 years 30 to 130 mg/dl (0.3 to 1.5 mmol/l)
Children up to 18 years 40 to 150 mg/dl (0.5 to 1.7 mmol/l)
Infants 40-200 mg/dl (0.5 to 2.3 mmol/l)
Newborn 10-230 mg/dl (0.1 to 2.7 mmol/l)

A different classification is shown in the National Cholesterol Education Program report.

Normal triglycerides Less than 150 mg/dl (< 1.7 mmol/l)
Borderline high triglycerides 150 to 199 mg/dl (1.7 to 2.3 mmol/l)
High triglycerides 200 to 499 mg/dl (2.3 to 5.7 mmol/l)
Very high triglycerides More than 500 mg/dl (> 5.7 mmol/l)

Indications

Triglyceride determination is required for the following health risks or diseases:

  • As a routine parameter to determine the risk of atherosclerosis, e.g., during regular blood level checks by your attending physician
  • For classification of an existing hyperlipoproteinemia – increased content of lipoproteins in the blood.
  • Therapy control during treatment with lipid-lowering drugs.
  • In acute pancreatitis (inflammation of the pancreas).

Interpretation

Elevated triglyceride levels are found in the following conditions or diseases:

1. isolated hypertriglyceridemia.

  • Familial hypertriglyceridemia, type IVa – elevation of VLDL, symptomatic, may be associated with increased risk of vascular disease.
  • Familial lipoprotein lipase deficiency, types I and V – elevation of chylomicrons, may be asymptomatic as well as associated with pancreatitis (inflammation of the pancreas), abdominal pain, and hepatosplenomegaly (enlargement of the liver and spleen).
  • Familial apo-CII deficiency, types I and V – like lipoprotein lipase deficiency.

2. combined hypertriglyceridemia and hypercholesterolemia.

  • Familial combined hyperlipidemia, type IIb – elevation of VLDL and LDL, usually without symptoms until vascular disease occurs; in the familial form, isolated high triglycerides or high LDL may occur.
  • Dysbetalipoproteinemia, type III – elevation of VLDL and IDL, LDL normal, usually without symptoms until vascular disease occurs; palmar (on the palm) or tuberoeruptive xanthomas (benign, to plum-sized growths) may occur

3. secondary hypertriglyceridemia.

  • Diet – increased intake of calories, saturated fat, carbohydrates.
  • Alcohol (woman: > 20 g/day; man > 30 g/day); esp. alcohol abuse.
  • Smoking
  • Obesity (obesity)
  • Lack of exercise
  • Pregnancy
  • Diabetes mellitus → dyslipidemia (dyslipidemia; triglycerides ↑, HDL ↓; diabetic dyslipidemia), even if glucose serum levels are well adjusted
  • Gout
  • Glycogenosis 1a – Congenital metabolic disorder with a deficiency of glucose-6 phosphatase.
  • Hypothyroidism (underactive thyroid gland).
  • Consumptive diseases, for example, AIDS
  • Monoclonal gammopathies – the appearance of monoclonal immunoglobulins in the blood.
  • Cushing’s disease – group of disorders leading to hypercortisolism (hypercortisolism; excess of cortisol).
  • Gaucher’s disease – storage disease with storage of cerebrosides in the cells.
  • Kidney disease – for example, chronic renal failure and nephrotic syndrome – clinical symptom complex accompanied by 1. proteinuria – protein excretion in the urine; 2. hypo- and dysproteinemia (deviations in the ratio of protein bodies of the blood plasma); 3. hyperlipidemia (lipid metabolism disorder); 4. hypocalcemia (calcium deficiency); 5. accelerated ESR (blood sedimentation rate); 6. edema formation (water retention).
  • Systemic lupus erythematosus – autoimmune disease with formation of autoantibodies v.a. against antigens of the cell nuclei (so-called antinuclear antibodies = ANA), possibly also against blood cells and other body tissues.
  • Drugs – for example:

Other notes

  • Isolated hypertriglyceridemias may be due to elevated VLDL levels (type IV) or the combination of VLDL and chylomicrons (type V). Rarely, chylomicron levels are elevated in isolation – type I.
  • Extreme hypertriglyceridemia occurs primarily in chylomicronemias – type I and type V according to Fredrickson. In these cases, blood levels of more than 1,000 mg/dl – 11.4 mmol/l – can be measured.
  • Lower triglyceride levels, usually of 200-500 mg/dl (2.3-5.7 mmol/l), are achieved in hypertriglyceridemia type IV according to Fredrickson. This condition occurs in adulthood and is often associated with diabetes mellitus, insulin resistance, obesity (obesity), and hyperinsulinemia (elevated blood levels of insulin).
  • It is generally known that elevated blood triglycerides are an independent risk factor for cardiovascular disease, such as coronary heart disease (CHD).
  • Caution. Very high triglyceride levels (> 1,000 mg/dl) can cause acute pancreatitis (inflammation of the pancreas).
  • Triglycerides, when not determined fasting, vary by approximately 20% (compared to a collective with fasting blood sampling).

Further diagnostics

  • In patients with triglyceride levels >200 mg/dl and metabolic dyslipoproteinemias (eg.B. Diabetes mellitus type 2, metabolic syndrome, android body fat distribution, that is, abdominal/visceral, truncal, central body fat (apple type), etc.), the calculation of non-HDL cholesterol (see below cholesterol) is also recommended.