New simpler rules for cholesterol testingPosted on November 18, 2009
I had an interesting conversation with a patient this week, who strenuously asserted that the link between cholesterol levels and heart disease remains “unproven”. As it happens, this month’s issue of the Journal of the American Medical Association (JAMA) has a major new study reviewing the link between cholesterol, heart disease and stroke, so I was able to show him the data.
The study group came up with some new findings, and re-confirmed some older findings:
1. HDL levels (high density lipoprotein) – aka “the good cholesterol” – is clearly protective for heart disease. Higher levels are strongly correlated with a reduced rate of coronary heart disease. We knew this already.
2. Everything else (other than HDL) in the cholesterol family is “bad”, with the risk of cardiac disease increasing significantly for non-HDL levels above 135 mg/ml. “Non-HDL cholesterol” is certainly simpler to remember than LDL’s, VLDL’s, chylomicrons and all the rest.
3. Triglyceride levels had no relation to heart disease risk in this study. Before you start celebrating, remember that excess triglyceride levels have been linked to pancreatitis.
4. Interestingly, there was no significant linkage between non-HDL (bad) cholesterol and stroke rates. That finding was unexpected.
5. Also new, Cholesterol levels did not vary significantly from the fasting and non-fasting states. Therefore, next time you go to have your cholesterol blood test, you will no longer need to skip breakfast.
Essentially, this study simplifies assessment of the lipid risk profile for cardio-vascular disease. Measure your total cholesterol and your HDL cholesterol, and don’t worry too much about the other cholesterol groups. And don’t worry about getting fasting lab work, unless the fasting state is needed for some other lab test, like glucose levels.