A new research has suggested the caution on medication to raise high-density lipoprotein (HDL) or 'good' cholesterol, which is believed to reduce the risk of heart attacks and related cardiovascular problems.
The research has found that only modest evidence supports the use of most medications to raise levels of HDL and some are even harmful.
The study was conducted by a team of researchers including author Mehdi Shishehbor at the Cleveland Clinic.
There are many types of HDL, not all of which nurtured the heart and blood vessels. The good kinds seemed to carry fat out of arteries to the liver and perform functions in cell membranes and elsewhere. However, HDLs vary considerably in size, density and other chemical properties that change their ability to sustain health.
Certain kinds of HDL could even increase inflammation, clogging arteries rather than clearing them, and doctors currently do not have a simple way to tell this 'bad' type of 'good' cholesterol from the genuinely beneficial kind in their patients.
As part of the study researchers conducted 31 randomized controlled trials to see the effect of HDL.
The evidences suggested that not everything that raised HDL was beneficial. Trials of one drug, torcetrapib, ended abruptly because the drug increased mortality risk and raised blood pressure. The class of diabetes drugs called thiazolidinediones (which include Avandia and Actos) increased HDL, but also seemed to raise the risk of cardiovascular problems.
As for pharmacological approaches, the study found that the most effective currently available drug to raise HDL is the vitamin niacin, taken in high doses.
Shishehbor noted that while efforts to lower low-density lipoprotein (LDL or 'bad cholesterol') "have consistently reduced cardiovascular disease risk, HDL-based approaches are much more complex and sometimes disappointing." As a result, "the primary focus should be on LDL."
The findings of the study were published in Journal of the American Medical Association (JAMA).