September 30, 2013
By Mary Pickett M.D.
Harvard Medical School
What's the latest news in the medical journals this month? Find out what your doctor is reading.
New Flu Shot Options For 2013
This year, you will find several new options when you go to get your flu shot. (The flu shot is recommended for everyone except infants younger than 6 months.) A review of available options was released by the Centers for Disease Control (CDC) September 20 in the Morbidity and Mortality Weekly Report (MMWR). Here are some of the new developments for 2013:
- "Quadrivalent" vaccines: Epidemiologists work hard to predict which flu strains will be the most important players during flu season. This helps vaccine makers develop vaccines with the right strains. Traditionally, flu shots have included proteins from three distinct strains of flu. This year, the World Health Organization and the U.S. Food and Drug Administration (FDA) asked vaccine makers to add a fourth strain to the vaccines. There was not enough time for every vaccine maker to convert to including four strains. So not all vaccines produced for the 2013-2014 flu season have this fourth strain included.
All nasal flu vaccines will be quadrivalent vaccines this year. Some injectable flu shots will be quadrivalent vaccines. You are more likely to receive a quadrivalent flu vaccine if you get your flu shot early in the season. Most injectable flu shots this year will continue to protect against three strains, not four.
- Nasal vaccine (FluMist): The nasal flu spray will continue to be available for children and adults under age 50 who do not have chronic illnesses and who are not pregnant. This vaccine contains live flu virus particles, but the flu virus in the vaccine has been weakened so that it does not cause illness. Although the nose spray creates a great immune response in kids and young adults, injectable flu shots seem to give more reliable response in adults over age 50.
- High-dose shots: Seniors over age 65 have a milder immune system boost from flu shots, compared with younger people. For this reason, a high-dose form of the vaccine was developed recently. It has four times the amount of flu protein. In studies, it does appear to trigger more antibody production in seniors. However, it also causes a higher rate of local reactions at the injection site, such as arm pain and skin redness.
Studies to test whether the high dose vaccine truly lowers flu infection rates are not yet complete. We should know this information in the fall of 2014.
All of the high-dose flu shots this year are "trivalent. "There is no high-dose version of the quadrivalent form yet. The CDC's Advisory Committee on Immunization Practices (ACIP) says any one of the injectable vaccines (high or standard dose, quadrivalent or trivalent) are appropriate for people over age 65.
- "Micro-needle" vaccine: For adults under age 65, one brand of flu shot (Fluzone Intradermal) has a needle that is less than a tenth of an inch long. This may be helpful for some adults who are fearful of needles. However, it has a lower dose of virus protein in the injection, so it might not provide the same immune system boost as standard flu shot vaccines. It also has a higher risk for local reactions, because it leaves the vaccine very close to the skin. The micro-needle vaccine is not available in quadrivalent vaccine form this year.
- Egg-free vaccine: Adults younger than age 50 who are allergic to eggs can get the "RIV3" (recombinant influenza vaccine) this year. The brand name is Flublok.
Even with all of these options, the best way to protect yourself against flu is probably to get whatever vaccine becomes available to you first. Flu shots give peak protection for 6 to 8 months after they are given.
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Migraines Linked to Brain Changes on MRI
Migraine headaches are common. The cause is unknown. Fortunately, most people with migraines have no long-term problems related to them. The headache is temporary, and once it's over the brain and body function normally. Stroke and other complications have been reported, but they are very rare.
But a new study raises the possibility that migraines may permanently change the structure of a person's brain.
The journal Neurology published the study August 28. Researchers reviewed information that had been collected in 19 previous studies. They compared brain MRI scans of people with migraines to those of people without migraines.
They found that people with migraines were more likely to have abnormalities in the "white matter" of the brain. They were also more likely to have smaller brain volume than normal. These variations were more obvious in people who had migraine with aura. (An aura is a symptom that happens around the time of a headache. Sometimes an aura is a visual symptom, such as flashing lights or blank areas in vision). The risk for having an abnormal brain MRI was 34% higher for people with migraine than it was for people who had no migraines. With migraine and aura, the likelihood of having an abnormal MRI was 68% higher than for people with no migraine.
The importance of these findings is uncertain. We don't know if migraines can cause the changes, or if the changes may have caused migraines.
We also don't know whether the abnormal areas of the brain cause the brain to function abnormally. Abnormal findings on MRIs are very common, and healthy people can have minor abnormalities with no impact on their health or brain function.
Still, this is the sort of finding that could change the way we think about migraine headaches.
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More News In Brief
- Statins May Increase Risk for Cataracts. A large study has its eye on cataracts as a possible side effect from cholesterol-lowering drugs called statins. The study was published online by JAMA Ophthalmology September 19. Nearly 14,000 veterans were included in the study. When the study began, 6,972 of the participants were taking statin drugs. An equal number were not taking statin drugs. Otherwise, the groups were pretty similar. Patients in the study were tracked for nearly 10 years. The group that took statins had a 27% higher risk for cataracts compared with the group that did not take statins. Researchers did not find an obvious way to explain this difference, aside from the exposure to statins.
Statins are trusted medicines. They are the most widely prescribed drugs in the United States. Even if statins may contribute to cataracts, it is hard to argue with the proven benefits of these drugs. Statins are recommended for anyone who has had a prior heart attack or stroke. They are also recommended for people at very high risk of having a heart attack. Still, serious side effects deserve our respect. For people who are at average or low risk for heart disease and have acceptable cholesterol levels, statin drugs probably do more harm than good.
- Diet and Exercise Help Knee Arthritis Pain. The Journal of the American Medical Association released a study September 25 that is encouraging to people with knee arthritis. According to this 18-month study, intensive dietary changes along with regular exercise led to better function, faster walking speed and less knee pain. In this study, 454 overweight and obese adults with osteoarthritis of the knee were treated with a gym-based exercise program and a diet program that promoted weight loss of 10% of body weight. This study is a good reminder that these practical steps are a wonderful first step in treatment of knee arthritis.
- E-Cigarettes May Help Some to Quit Smoking. Electronic cigarettes, commonly known as e-cigarettes, are battery-operated devices that are shaped like cigarettes. They give off a flavored vapor. Sometimes that vapor contains nicotine. They give the illusion and feel of smoking a cigarette. E-cigarettes are not regulated and their safety has not been proven. However, a study published September 7 by the Lancet does suggest that they might help smokers to cut down or quit, if they are used as an aid to stopping smoking.
Researchers enrolled 657 smokers who were interested in quitting. Of these patients, 292 were given e-cigarettes with nicotine to use during their quit attempt. Another 292 patients were given nicotine patches, which have proven benefit as an aid to smoking cessation. A third group--the remaining patients--were given a placebo e-cigarette, which did not release any nicotine.
Over the next 13 weeks, 7.3% of people in the e-cigarettes group quit smoking. This was similar to the quit rates of people who used nicotine patches. People who got the placebo e-cigarettes had a quit rate of 4.1%. Fifty-seven percent of the e-cigarette group were able to cut down their (regular) cigarette smoking by at least half in the 6 months after starting e-cigarette use. It is remarkable in studies like this to see how hard it is for most people to quit smoking in one attempt. Usually, multiple attempts at quitting are needed. E-cigarettes may provide some help to people who are trying to quit smoking. However, until these devices are regulated and their safety can monitored, doctors are more likely to recommend other quitting aids.
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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.