What does lipaemia index mean?
The lipaemia index is a laboratory value that shows how much a blood sample has been clouded by fat particles. It is measured automatically during many blood tests to assess the quality of the sample and to spot any possible interference with the analysis.
When blood turns milky
Normally, blood serum, which is the liquid part of blood after it has been spun in a centrifuge, looks clear or slightly yellowish. However, if it contains a particularly large number of fat particles, known as lipids, the serum appears cloudy or even milky. This cloudiness is called lipaemia. The lipaemia index describes how pronounced this cloudiness is. The higher the value, the more heavily the sample is affected by fats.
Many laboratories measure the lipaemia index automatically using specialist equipment. The result is usually given as a number or in levels. A low index indicates a clear sample, while a high value points to significant lipaemia.
Why is the lipaemia index measured?
Fats in the blood are completely normal and vary depending on diet and metabolism. However, when too many fat particles are present, laboratory results can be distorted. Certain blood values can no longer be measured reliably because the cloudiness interferes with the analysis. The lipaemia index helps the laboratory to identify such samples and to interpret the results correctly.
The lipaemia index is often measured automatically alongside other so-called interference indices, such as the haemolysis index or the icterus index. This allows the laboratory to quickly see whether a sample is suitable for evaluation or whether a note about possible interference is needed.
What does a raised lipaemia index mean?
A raised lipaemia index means that an unusually large number of fat particles are present in the blood. This can have harmless causes, for example if the person did not fast before the blood test and had eaten fatty food shortly beforehand. Certain medicines or metabolic conditions can also lead to stronger lipaemia.
In rare cases, a disorder of fat metabolism may be the cause, such as a condition called hyperlipidaemia. In this case, there are persistently too many fats in the blood, which can increase the long-term risk of cardiovascular disease. In most cases, however, a one-off raised lipaemia index is not a cause for concern, but rather an indication that the sample may be unsuitable for some measurements.
What happens when a sample is flagged?
If the laboratory detects a high lipaemia index, this is noted in the report. Some laboratory values may then not be measurable, or only to a limited extent. In such cases, certain analyses may need to be repeated, often after a fresh blood sample is taken, ideally while fasting.
A note about lipaemia does not automatically mean that a serious condition is present. It is often enough to avoid fatty foods before the next blood test and to fast for a few hours beforehand. Only if repeatedly high values occur might a more thorough investigation be worthwhile.
When is the lipaemia index important?
The lipaemia index is primarily a technical laboratory value and not a diagnosis of illness. It is used to assess the quality of the blood sample and to identify possible sources of error in the analysis at an early stage. It is only relevant for assessing your own health if unusual results appear alongside other blood values.
In most cases, the lipaemia index simply gives an indication of the condition of the sample. Only if persistently very high values are measured, or if other laboratory values are unusual, should a doctor be consulted about whether further investigations are needed.
