Healthoughts
the rise and fall of cholesterol
In spite of what you may have heard, not all cholesterol is created equal.
In fact, having a lot of the right kind of cholesterol may offer significant protection from heart attacks, strokes and other cardiovascular diseases.
Howard Hodis, M.D., professor of medicine and preventive medicine at the Keck School, says that high-density lipoproteins (HDLs), or "good cholesterol,' patrol the circulatory system, helping remove the plaques of low-density lipoproteins (LDLs), or "bad cholesterol" that can clog arteries.
The American Heart Association considers HDL levels lower
than 40 milligrams per deciliter to be a major risk factor for
heart disease, while levels of 60 and higher are considered protective
against heart disease. Total 
cholesterol
should be kept under 200 milligrams per deciliter and LDLs should
be ideally kept under 100 for individuals with cardiovascular
disease and diabetes and under 130 for everyone else.
Hodis says that people may be able to raise their good cholesterol levels and lower their bad cholesterol levels-significantly decreasing their heart disease risk-by changing their behavior.
"The biggest offender in depressing HDL levels is smoking, but once a person quits, their HDL is bound to come up,' Hodis says.
The next most important thing is to engage in aerobic exercise at least three days each week for at least 30 minutes each day. Any activity that gets a person's heart rate to about 80 percent of its maximum will suffice. A person's maximum heart rate is generally calculated by subtracting their age in years from 220.
Another form of fat called triglyceride is found in the blood, usually in inverse proportion to the amount of HDL. So essentially, anything that lowers the levels of triglycerides-such as losing weight or reducing excessive carbohydrate intake tends to increase HDLs.
Triglycerides may also come down and HDL may rise when a person replaces the saturated fats found in milk, butter and cheese in their diets with monounsaturated fats found in olive, canola and peanut oils.
Hodis stresses: "The key word here is 'replaces? It does no good if people add monounsaturated fats to a diet that already has too much fat."
nothing to cough at
British scientists recently suggested that over-the-counter cough medications are no more effective than placebos, but a USC pharmacy expert says you shouldn't throw out your cough syrup just yet.
James Adams, Ph.D., associate professor of molecular pharmacology and toxicology, says the analysis of studies performed by University of Bristol researchers had several flaws.
For example, it included tests of antihistamines, which have never been touted as having cough-inhibiting properties. It also focused on the number of coughs people reported instead of also examining the characteristics of their coughing.
"You don't know whether people were so uncomfortable as a result of the coughing that they couldn't sleep, or whether it was something fairly minor;' Adams says.
The British researchers examined data from 15 different studies involving a total of 2,166 adults with acute coughs. In most of the studies, participants kept diaries of their cough symptoms. The studies tested not only cough-suppressants but also expectorants, antihistamines and other combinations of medications.
But Adams strongly doubts the conclusion that cough medications are worthless.
"Frankly, the study really isn't telling us anything useful. Medications such as dextromethorphan and codeine have been tested in clinical trials and scientific studies and have been shown to inhibit coughing,' he says. "Does that mean if you take them, you won't cough at all? No. But the cough will probably bother you less?'
bacterial back door
A root canal can relieve the pain of a cracked tooth-but it also may give germs a back door into the bloodstream.
For most people, the mouth's bacteria cause little more harm than tooth decay. But for those with certain heart conditions, such as murmurs, letting these bacteria into the blood maybe potentially dangerous.
Because bacteria can settle on heart valves and cause infective endocarditis, dentists and cardiologists ask that patients with heart murmurs take preventive antibiotics before dental procedures that might cause significant bleeding. These can include extractions, gain surgeries and even deep cleaning, says Tom Pallasch, D.D.S,, M.S.,USC professor emeritus of dentistry.
But before over-medicating with antibiotics or avoiding the dentist chair altogether, it is best to understand the facts, says Pallasch.
First, he says, endocarditis is extremely rare, occurring in only about 10,000 people a year, with infections also coming from surgeries and unknown sources. Risks of developing the disease depend on the degree of heart problems. People with prosthetic heart valves, those with previous endocarditis and children with complex heart disease are at highest risk.
Physicians determine the extent of heart valve problems by listening to the heart with a stethoscope and performing echocardiograms. A diagnosis of a damaged aortic or mitral valve usually prompts doctors to recommend antibiotics before dental visits.
Because many bacteria are growing resistant to antibiotics due to their wide use, health experts must reweigh the risks and benefits of administering them, Pallasch says.
"With antibiotic prophylaxis, most who get antibiotics wouldn't have gotten endocarditis," he says, but health experts have favored being on the safe side.
For now, Pallasch recommends that patients get a full description of their heart condition from their doctor, share it with their dentist and make sure to take antibiotics when asked.
diabetes direct
Blood sugar meters for people with diabetes have gone high-tech, according to Anne Louise Peters Harmel, M.D., director of the USC Westside Center for Diabetes and the Comprehensive Diabetes Center at Roybal Community Medical Center in East Los Angeles.
Traditionally, patients have had to prick a finger and squeeze a large drop of blood onto a chemically treated strip, and a meter measured the resulting chemical reaction to determine how much glucose is in the blood. Old meters took two minutes to give an answer. But new meters require only a tiny puncture, with results given in five seconds.
Moreover, meters also now help patients keep track of sugar levels. Instead of requiring patients to write down numbers on a sheet that must be taken to the doctor's office, computerized meters themselves store the information. Patients in USC'S Westside and Roybal clinics take the meters with them to appointments, where the information is downloaded and reviewed.
Harmel is excited about the potential of several new compact, consumer-friendly meters to record even more information, such as diet, exercise and amount of insulin used. Such information will help physicians and patients better customize patients' glucose control.
Still, there is a danger that patients' attentiveness to sugar levels will wane if the information simply goes into computer memory "I make patients look at the numbers," she says. "Diabetes is an interactive disease, and these new tools help the interaction, but they don't mean you stop paying attention,"
Some new meters also can check blood sugar levels by testing blood from the arm or leg, though most of Harmel's patients still prefer fingertip testing. And though meters have improved, no one has yet done away with finger-sticking entirely.
"Lots of people are researching ways to noninvasively measure glucose;' she says. "Anyone who creates a less-invasive way of measuring blood sugar dependably will make a big stride in the diabetes war?'
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