News Review From Harvard Medical School -- LDL Particle Test Gains Support
Some doctors are using an extra blood test to help assess who needs treatment for cholesterol problems. The Associated Press (AP) wrote about the test October 25. The test counts the particles that carry LDL -- the so-called bad cholesterol -- in the blood. LDL can be contained in many small particles or fewer large ones. The small ones are more likely to build up inside artery walls. The National Lipid Association, a group of doctors who treat cholesterol problems, has looked at use of the particle tests. This month, a committee of this group said the tests would be reasonable to use for some patients. They could help doctors to decide who should start drug treatment or increase it to lower LDL. But some experts say current tests are enough, AP said. They say that particle levels usually reflect overall LDL levels. Doctors also can look at non-HDL cholesterol. This can help decide who is at risk, one expert told AP. The number can be calculated from standard cholesterol tests. It's equal to total cholesterol minus HDL, the so-called good cholesterol.
By Howard LeWine, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Cholesterol has a bad name. But we actually couldn't live without cholesterol. It is the foundation of many substances we need to live.
It's the cholesterol in our blood that gives it the bad name.
Cholesterol doesn't float around on its own in our blood stream. It attaches to proteins. Proteins containing cholesterol are called lipoproteins.
Some lipoproteins have the potential to be dangerous. Low-density lipoprotein (LDL), the so-called bad cholesterol, is the one we worry about the most. LDL has lots of fat ready to be deposited in arteries. People with a high blood level of LDL have a higher risk of heart attacks and blood vessel diseases.
On the other hand, high levels of cholesterol packaged as high-density lipoprotein (HDL) are linked with a reduced risk of heart attack. HDL is the so-called good cholesterol. HDL contains lots of protein. But, unlike LDL, it contains little fat. HDL sponges up excess cholesterol from the lining of blood vessels.
LDL is the foundation on which the current cholesterol guidelines were built. It's the main test used to determine if you need a drug, such as a statin, to lower cholesterol.
However, LDL cholesterol level is far from a perfect predictor. Not everyone with high LDL has a heart attack. Up to half of all heart attacks happen to people with normal LDL.
That's why researchers continue to study other tests. They are always looking for one that might offer a clearer picture of heart disease risk. These extra blood tests include:
Lipoprotein particle tests -- Not all LDL cholesterol carries the same risk. Smaller, more tightly packed LDL has an easier time getting into arteries. Fluffier particles are less dangerous. Special blood tests can determine your levels of the different particles.
C-reactive protein (CRP) -- CRP is a measure of inflammation. People with long-lasting inflammation have a higher risk of heart and blood vessel diseases.
Non-HDL cholesterol -- This is not really a new test. It's a different way to use the numbers on a standard cholesterol test to gauge heart disease risk. You simply subtract the level of HDL from total cholesterol. A non-HDL level of less than 160 milligrams per deciliter (mg/dL) is good. Less than 130 mg/dL is great. If you already have heart disease, your doctor may set an even lower goal.
What Changes Can I Make Now?
It's unlikely you will need any special tests beyond a standard fasting cholesterol test. It measures:
Total cholesterol
LDL cholesterol
HDL cholesterol
Triglycerides
Determining who should take a statin or other drug to lower cholesterol depends upon your overall risk of heart disease. Other factors that increase risk include:
Family history of coronary heart disease, especially under age 60
Smoking
Diabetes
High blood pressure
If you have two or more of these risk factors, you should consider taking a statin if your LDL cholesterol is greater than 100 mg/dL.
Many doctors would suggest taking a statin if:
You have an LDL level of 130 mg/dL and one other risk factor
You have an LDL level between 160 mg/dL and 189 mg/dL and no other risk factors
In either of these two cases, you might wonder if you really need to take a statin. Other tests, such as CRP or particle tests, might help you decide.
What Can I Expect Looking to the Future?
Through genetics research, scientists keep making new discoveries about prevention of heart disease and other long-term conditions. As a result, choosing treatments should become less confusing in the future.
Last updated October 26, 2011
From Wikipedia, the free encyclopedia
Harvard Medical School (HMS) is the graduate medical school of Harvard University. It is located in the Longwood Medical Area of the Mission Hill neighborhood of Boston, Massachusetts.
HMS is home (as of Fall 2006) to 616 students in the M.D. program, 435 in the Ph.D. program, and 155 in the M.D.-Ph.D program.[1] HMS' M.D.-Ph.D program allows a student to receive an M.D. from HMS and a Ph.D from either Harvard or the Massachusetts Institute of Technology (see Medical Scientist Training Program). Prospective students apply to one of two tracks to the M.D. degree. New Pathway, the larger of the two programs, emphasizes problem-based learning. HST, operated by the Harvard-MIT Division of Health Sciences and Technology, emphasizes medical research.
The school has a large and distinguished faculty to support its missions of education, research, and clinical care. These faculty hold appointments in the basic science departments on the HMS Quadrangle, and in the clinical departments located in multiple Harvard-affiliated hospitals and institutions in Boston. There are approximately 2,900 full- and part-time voting faculty members consisting of assistant, associate, and full professors, and over 5,000 full or part-time non-voting instructors. HMS is currently ranked first among American research medical schools by U.S. News and World Report, and ranked 21st among research medical schools in the amount of competitive grants received from the NIH.[2][3]
The current dean of the medical school is Dr. Jeffrey S. Flier, an endocrinologist and the former Chief Academic Officer of the Beth Israel Deaconess Medical Center, who succeeded neurologist Joseph B. Martin, M.D., Ph.D on September 1, 2007.[4] Sanjiv Chopra, M.B.B.S, MACP is the Faculty Dean for the Continuing Education Department.
Medpedia:
Harvard Medical School is one of the world's preeminent institutions in medical education and research. The student body comprises more than 700 men and women in the M.D. program, more than 600 students in the Ph.D. program, and of those many are in the joint M.D.-Ph.D. programs, part of which is sponsored in collaboration with Massachusetts Institute of Technology. They are taught by a faculty of more than 9,000, the largest graduate faculty at Harvard and the largest medical faculty in the world.
The research carried out by Harvard Medical School faculty is at the forefront of basic biomedical science and clinical research. In the school's distinguished 224-year history, 15 faculty members have been recognized for their work with the Nobel Prize.
Harvard Medical School has, since 1975, published information about health for the general public, through books, newsletters, magazines, a syndicated weekly newspaper column, and content licensed to Web sites (www.health.harvard.edu). Over 300 members of the faculty are engaged in writing and editing health information for the general public.
For its medical students, Harvard has inaugurated the New Pathway curriculum, a problem-solving, case-method approach to learning, which offers students the opportunity to come in contact with patient cases early in their studies. Students work and learn in 18 affiliated facilities:
