Update From the Medical Journals: January 2013
January 30, 2013
By Mary Pickett, M.D.
What's the latest news in the medical journals this month? Find out what your doctor is reading.
The U.S. Food and Drug Administration (FDA) says sleeping pills lead to unsafe driving even when the driving occurs the day after use.
The FDA held a press conference and issued an online alert January 10 to announce that it cut in half the maximum dose for women taking certain sleeping pills. Medications that are affected contain zolpidem. They include Ambien, Edluar, Zolpimist, generic zolpidem and Ambien CR.
The maximum dose for Ambien CR for women will be 6.25 milligrams. The maximum dose for other sleeping pills with zolpidem will be 5 milligrams. Intermezzo, a zolpidem drug designed for middle-of-the-night use, already has a lower dose than other pills. For Intermezzo, the FDA says it should never be used if a person does not have at least four additional hours of sleep time left in the night. People should not use Ambien, Ambien CR and other brands unless they have at least 7 to 8 hours of available sleep time.
The dose changes were based on driving simulation studies. They showed that 15% of women and 3% of men had an unsafe level of drug in their bloodstream the morning after use, if they took the short-acting version of the drug. Thirty-three percent of women and 25% of men had unsafe drug levels 8 hours after use, if they took the long-acting version of the drug (Ambien CR). The medication caused poor coordination and a lack of alertness in driving tests, even for drivers who did not feel "drowsy."
In the press conference, the FDA experts recommended that men use a lower maximum dose of the drug just as women, but they are formally requiring the change only for women. The FDA has hinted it will put other sleep drugs through similar testing. The FDA has received more than 700 reports of unsafe driving or road accidents that have occurred after use of Ambien. Most of these reports have been submitted in the last 5 years.
The Centers for Disease Control and Prevention (CDC) released early estimates on January 11 about how well this year's flu shot is doing its job. They are based on 1,155 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).
Thirty-two percent of people who tested positive for flu reported that they had the flu vaccine earlier in the year. Fifty-six percent who tested negative for flu said they had received the vaccine. By doing some math, researchers were able to report that the flu vaccine is 62% or "moderately" effective this year. This means it is possible to get the shot and still get the flu, even though the vaccine does make flu less likely.
When the flu shot is "moderately" effective, it also means less antibiotic use, less time lost from work and fewer hospitalizations and deaths.
A flu shot is strongly recommended for all people older than 6 months. It's not too late to get one.
So far this year, flu has been severe and widespread. By January 12, CDC had reported 29 deaths in children. On January 9, Boston declared a public health state of emergency due to flu. On January 12, a state of emergency was also declared for the state of New York.
Most lung cancer is already in an advanced stage when it is diagnosed, so it can't be cured with surgery. Yearly chest X-rays are not a useful screening test, because they can miss many cancers that are small enough to treat. But yearly computed tomography (CT) scans can reduce your chance of dying from lung cancer by a small amount, if you are a heavy smoker.
The American Cancer Society (ACS) now recommends that heavy smokers consider screening with CT to find early lung cancers. The guidelines were published online January 11 in CA: A Cancer Journal for Clinicians. The ACS limits this recommendation to people who:
The ACS also says that each patient should know that the test only has a small benefit. They should be aware of the problems testing raises before deciding whether to have the yearly test. These include costs, convenience factors, repeated exposure to radiation and a risk of having a false-positive result with potential for medical harm.
Our best view of how well CT works for smokers came from the National Lung Screening Trial, which published its results in 2010. This study monitored smokers who had a "spiral" computed tomography (CT) scan once a year. The spiral CT shows the lungs in detail, so it can find small cancers. People who got the CT scans were 20% less likely to die of lung cancer in the 5 years after beginning screening, compared with smokers who got X-rays.
A 20% difference sounds like a lot. However, it's important to consider how many people need to be tested to potentially save one life. According to the same 5-year study, in order to save 1 smoker or former smoker from dying of lung cancer, 303 people needed to get a yearly CT scan.
The scans were not a perfect test. One out of four people had a false-positive test. That is, the scans showed possible lung cancer, but additional testing showed there was no cancer after all. A false-positive test can lead to unnecessary surgery.
The best way to prevent lung cancer is to stop smoking. If you have been a heavy smoker, you can consider having a yearly CT scan to look for lung cancer. This test may find a lung cancer while it is small and most easily treated.
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.