What's the latest news in the medical journals this month? Find out what your doctor is reading.
- Americans' Sugary Diets Lead to Heart-Related Deaths
- Stroke Prevention Guidelines Issued for Women
- More News in Brief: Pesticide Use Linked to Parkinson's; Home Stool Test Can Find Most Colon Cancers; Newer Drug is Helpful for Restless Legs; This Year's Flu Shot Works Moderately Well
A study published online February 3 by JAMA Internal Medicine says eating too much added sugar dramatically increases the risk for heart-related death. Added sugars include corn syrup, cane sugar, brown sugar and honey. They are found in processed foods and drinks. The sugar you stir into coffee or use in baking also is added sugar.
Research in the past several years has linked added sugars in the American diet to changes in our metabolism — the rate at which our bodies expend energy or burn calories. Sugar has been linked to obesity, diabetes, cholesterol problems and high blood pressure. But this new study used valid statistical methods to show how too much sugar, by itself, increased heart-related deaths. The information may sour you on sugar.
Scientists at the U.S. Centers for Disease Control and Prevention did the study. They took into account many other health factors known to contribute to heart problems (age, smoking, cholesterol levels, blood pressure, lack of exercise and excess weight). Death rates were still higher for those who ate more sugar. Added sugar increased the risk for heart-related death, even for normal-weight people with good blood pressure and cholesterol levels. An average American eats 14.9% of calories in the form of added sugar. This increased the risk for heart-related death by 18%.
The risk of heart-related death was twice as high for people who ate more than 20% of their calories as added sugar, compared with people who consumed 8% of calories as added sugar. According to information collected by the American Heart Association (AHA) between 2001 to 2004, Americans ate the following amounts of added sugars a day:
- Average child or teenager – 21 to 34 teaspoons
- Average woman – 18 teaspoons
- Average man – over 25 teaspoons
For men and women, this is roughly 3 times the amount of added sugar that we should be eating daily. The AHA recommends:
- No more than 25 grams (6 teaspoons or 100 calories) of added sugar for women
- No more than 38 grams (9 teaspoons or 150 calories) for men
- No more than 12 grams (3 teaspoons or 50 calories) for children ages 4 to 8 years
A single 12-ounce soda has about 8 teaspoons of sugar. One-third of the sugar Americans get in their diets comes from soft drinks. Between 1970 and 2005, Americans increased their daily average intake of added sweeteners by 19%. Half of the increase came from sweetened beverages like sodas.
Women face a higher lifetime risk of stroke than men. And they have unique health issues that can increase their risk of stroke. The American Heart Association and American Stroke Association jointly published the first set of stroke prevention guidelines just for women. The guidelines were released online February 6 by the journal Stroke.
Many health conditions increase stroke risk for both women and men. Both need to control high blood pressure, cholesterol and weight. Both can decrease their risk by avoiding smoking and diabetes. But the guidelines note that women's risk of stroke also is affected by pregnancy and hormones.
These risk factors are unique to women, or more strongly predict stroke for women than men:
- Preeclampsia (high blood pressure, leg swelling from edema and protein in the urine during pregnancy)
- Gestational diabetes (new diabetes during pregnancy)
- Birth control pills
- Hormone replacement after menopause
- Migraine with aura (seeing flashing lights or having other neurological symptoms just before the headache)
- Atrial fibrillation (irregular heart beat)
- High blood pressure
The guidelines focus on four areas for women:
- Be aware of your blood pressure even when you are young. Women should pay attention to their blood pressure before starting birth control pills or getting pregnant. Birth control pills can increase the risk of stroke, especially for women with high blood pressure. And pregnant women with high blood pressure may need treatment to prevent preeclampsia. This dangerous problem in pregnancy also doubles the risk of stroke later in life.
- Smoking multiplies your risk. Smoking particularly increases stroke risk for women who have migraine with aura, take birth control pills or have high blood pressure.
- Atrial fibrillation is important to catch. Older women (especially women over age 75) should have their pulse checked to see if it is irregular. This can help diagnose atrial fibrillation. Both women and men with atrial fibrillation have an increased stroke risk, but it is higher for women. So they must either have their heart rhythm restored to normal or take a blood thinner medicine to help prevent stroke.
- Aspirin helps prevent stroke. Women ages 65 through 79 should consider taking a daily baby aspirin (81 milligrams). Aspirin has a small risk of internal bleeding. Always talk to your doctor first before starting regular aspirin therapy.
- Pesticide Use Linked to Parkinson's. Parkinson's disease is a common disease of the central nervous system. The cause is a mystery. We know that Parkinson's is partly related to genes. The risk for Parkinson's is about 2% for someone who has a parent or sibling with the disease, and only 1% for the population at large. But genes alone are not enough to explain who gets the disease.
In the last 5 to 10 years, a handful of studies have suggested that exposure to pesticides might increase the lifetime risk for Parkinson's. On February 5, the journal Neurology released a study online of about 1,100 people. It showed that having a certain gene variant could make some people more vulnerable to Parkinson's. The research is very exciting, because it may help us to understand Parkinson's more clearly than ever before.
Roughly one third of the Parkinson's patients have gene variations that were interesting to the researchers. These gene variations cause a problem in the making of an enzyme called aldehyde dehydrogenase (ALDH). ALDH breaks down byproducts of dopamine, a brain hormone. If ALDH does not function, this can lead to the kind of nerve damage that is seen in Parkinson's disease — a shut-down of dopamine-producing brain cells. Before enrolling people in the study, the researchers used lab experiments to show that some pesticides blocked ALDH. Several of these pesticides are used in farming.
These researchers then studied 360 people in California with Parkinson's, and 816 people who did not have the disease. Pesticide exposure was estimated based on their work and home address, and the timing and location of pesticide spray events. (Researchers used pesticide exposure maps from the California Department of Pesticide Regulation.) The researchers also did genetic testing on most of the subjects to look for genes that they carried. For people without any variation in genes relating to the ALDH enzyme, there was no obvious connection between pesticide exposure and Parkinson's. But for people who did have one of several variations in this gene, pesticide exposure was strongly related to Parkinson's. Mathematical analysis showed that when both the gene variation and pesticide exposure were present, the chance of a person developing Parkinson's was 2 to 5 times higher than the population average. This study does not give us a new way to treat Parkinson's, but it might eventually lead us to treatments that could slow its progression, or to ways to prevent the disease.
- Home Stool Test Can Find Most Colon Cancers. Colon cancer screening is a good idea. Tests such as a colonoscopy can find cancer before it has spread to lymph nodes. When colon cancer is detected early, surgery and chemotherapy can cure about 9 out of 10 people.
The most common test used to screen for colon cancer is a colonoscopy. It's considered an invasive test. It requires the bowels to be cleaned out or "prepped." And a person is almost always sedated. Is there another way to detect colon cancer? A test called the "fecal immunochemical test" (FIT) may be the answer. For this test, you collect three stool samples at home. They are mailed in to your medical provider and tested for "human hemoglobin," which is present in fresh blood. A positive test indicates bleeding from the colon; if you are bleeding from the stomach or esophagus, the test is usually negative. If the test is positive, a colonoscopy is needed to find the bleeding source in case it is a cancer. This test does not lead to a colonoscopy as often as the older "guaiac" stool test, because it does not detect blood from irritation in the stomach or esophagus.
The Annals of Internal Medicine released a review about the accuracy of the FIT test for colon cancer on February 4. If the test is done yearly, and if a colonoscopy occurs after a positive test, the test will detect about 79% of colorectal cancers, according to the study. Some, but not all, physician offices offer this test. It is a reasonable way to do your colon cancer screening, as long as you do the test yearly and follow up with a colon examination for any positive test.
- Newer Medicine is Helpful for Restless Legs. People with restless legs syndrome are kept awake by an uncontrollable urge to move their legs. For some people, iron supplementation can relieve the symptoms completely. But some people with restless leg syndrome need medication to suppress their symptoms. A new study published February 13 in the New England Journal of Medicine finds that the drug pregabalin (Lyrica) may be an effective treatment. It included 720 people with restless legs syndrome. They were randomly divided into groups. One group took the commonly prescribed drug pramipexole (Mirapex), another group took pregabalin (Lyrica) and the third group took a placebo (fake pills). After 12 weeks of treatment, pregabalin improved symptoms as well as pramipexole (both were better than placebo). One bothersome side effect with pramipexole is "augmentation." This is a rebounding of symptoms—after long-term use, a small number of patients have found that the medicine actually seems to make things worse. This might be less likely with pregabalin. Pramipexole will continue to be an excellent option for treating restless legs. But it is nice to add pregabalin to that list.
- This Year's Flu Shot Works Moderately Well. This year a lot of people have been walloped by the flu. But according to the Centers for Disease Control and Prevention (CDC), this year's flu shot is 61% — or "moderately" — effective. This means it is possible to get the shot and still get the flu, but the vaccine does make flu less likely. This is not a bad result. Reducing flu even "moderately" means less flu spreads through our homes, schools and communities. This cuts down on antibiotic use, time lost from work and hospital stays and deaths, even for people who do get the flu.
How does 61% compare? It is about the same as last year. In our best years, the flu shot protects against 70% to 90% of circulating flu virus infections. Six years ago in 2007-2008, it was only 44% protective. Even when it isn't perfect, vaccination is still our best prevention.
One specific flu virus-- influenza A (H1N1) -- accounted for 98% of the flu cases that were detected this year. Surprisingly, flu has hit young and middle-aged people particularly hard. People age 18-64 made up 61% of all people who were hospitalized with flu—almost double what is usual. More influenza deaths than usual also occurred in this younger age group.
The CDC based the 61% effectiveness on 2,319 people who had severe enough cough and cold symptoms to see a doctor. All of the patients had nasal swab tests to check for influenza (flu). Twenty-nine percent of people who tested positive for flu reported that they had the flu vaccine earlier in the year. Fifty percent who tested negative for flu said they had received the vaccine. By doing some math, researchers got the 61% effectiveness number. The statistic was published February 21 in the Morbidity and Mortality Weekly Report.
Mary Pickett, M.D., is an associate professor at Oregon Health Science University where she is a primary care doctor for adults. She supervises and educates residents in the field of Internal Medicine, for outpatient and hospital care. She is a lecturer for Harvard Medical School and a senior medical editor for Harvard Health Publications.