‘Good’ cholesterol not always so good

Good cholesterol‚ or HDL‚ is seen to protect people against cardiac risks like stroke or heart attacks.

But the new research has uncovered a link between extremely high levels of HDL in the blood and higher rates of death.

Compared to people with normal levels of HDL‚ extremely high levels of good cholesterol were correlated with:

- 106% higher mortality rate for men; and

- 68% higher for women.

Study co-author‚ Professor Børge Nordestgaard from the University of Copenhagen‚ said: “The results of a new study seriously contradict the assumption that high levels of HDL in the blood are only a good thing.

“These results radically change the way we understand 'good' cholesterol‚” said Nordestgaard.

“Doctors like myself have been used to congratulating patients who had a very high level of HDL in their blood. But we should no longer do so.”

Very low HDL in the blood is also a risk.

The researchers found “excessive mortality” associated with people with extremely low levels of HDL.

They analysed data from more than 100‚000 people for an average of six years and their results were based on about 10‚000 deaths.

Nevertheless further investigation was needed to reach any conclusions about very high HDL and mortality‚ the authors noted.

Vitality clinical specialist Dr Deepak Patel said this observational study did not show how very high HDL could cause increase mortality.

But moderately high HDL was proven with overwhelming evidence to reduce the risk of cardiovascular disease‚ he said.

However‚ treatments elevating HDL had not generally improved cardiovascular health‚ he reported.

Patel said: “HDL continues to be used in cardiovascular risk analysis such as the Framingham Risk score.”

Doctors’ decisions about whether patients with high cholesterol should go on statins‚ are partly informed by this score.