Two reports published this week in the journal BMJ weren’t exactly an April Fool’s Day message about vitamin D, but they came close.
For the past few years, vitamin D has been gaining a reputation—not entirely earned—as a wonder vitamin that offers protection against some cancers, bone-weakening osteoporosis, heart attack, Alzheimer’s disease, and other chronic conditions. Not so fast, caution the two reports.
In one of the BMJ studies, led by Evropi Theodoratou, a research fellow at the University of Edinburgh, researchers evaluated the results of 268 previous studies of vitamin D. Their conclusion: “highly convincing evidence of a clear role of vitamin D does not exist for any outcome, but associations with a selection of outcomes are probable.” In other words, there’s no solid proof that taking vitamin D helps.
The other BMJ study, led by Rajiv Chowdhury, a cardiovascular epidemiologist at the University of Cambridge, showed that low blood levels of vitamin D are linked to increased risks of dying prematurely from cardiovascular disease, cancer, and other causes. But whether supplementation with vitamin D can help people live longer and healthier requires more study.
One big unknown is whether low vitamin D causes chronic conditions, or whether chronic conditions cause low vitamin D levels. Another area of mystery is what type of vitamin D supplement would be best for health, and how much to take.
Testing for vitamin D
Some doctors routinely check their patients’ vitamin D levels. The authors of one of the studies question this practice. They say the evidence so far doesn’t show significant differences in health between young and middle-aged people with lower blood levels of vitamin D. The authors acknowledge that it might be different for older people, in whom improving the blood level of vitamin D may be beneficial.
If not everyone should be tested for vitamin D, who should have a blood test for it? Like so much else about vitamin D, there’s no clear answer. I advise the test for people who have bone-thinning osteopenia or osteoporosis or who are at high risk of developing it, such as
Caucasian and Asian women just before and any time after menopause, especially if they smoke or are thin women and older men with a family history of osteoporosis individuals who have had a hip, wrist, spine, or other fracture after age 50 individuals who take a medicine that thins bones, such as a corticosteroid
Should you take vitamin D?
I plan to keep advising my patients to get the amount of vitamin D recommended by the Institute of Medicine:
600 IU of vitamin D a day for everyone ages 1 to 70 800 IU of vitamin D a day for those 71 and older
Food is usually the best way to get vitamins. But not vitamin D. Only a few foods—salmon, tuna, sardines, milk, fortified cereals, and some types of mushroom—can give you more than 100 IU per serving.
What about the way humans have gotten vitamin D for millions of years—from the sun? It’s a hot-button issue—and a balancing act. Getting 10 to 15 minutes of sunlight on your face, arms, back, or legs without sunscreen a few times a week is enough to generate your body’s vitamin D needs for a week. But too much exposure to the sun causes skin cancer.
If you rarely get out in the sun, or just aren’t certain you are getting 600 to 800 IU of vitamin D a day, taking a supplement containing 400 to 1,000 IU is safe, inexpensive insurance.
Severe headaches are a misery, whether they cause a dull ache or a steady, stabbing, or blinding pain. Writer and migraine sufferer Stephen King described a character’s migraine attacks this way in the novel Firestarter: “The headache would get worse until it was a smashing weight, sending red pain through his head and neck with every pulse beat. Bright lights would make his eyes water helplessly and send darts of agony into the flesh just behind his eyes. Small noises magnified, ordinary noises insupportable.”
The pain of even a severe headache rarely comes from something catastrophic like a tumor or a bleeding in the brain. But fear of such cerebral catastrophes often drives people to get brain scans. According to a report published this week in JAMA Internal Medicine, about one in 10 people who seek outpatient care for severe headaches ultimately end up having a brain scan with computed tomography (CT) or magnetic resonance imaging (MRI). Most of them find nothing wrong.
People struck with agonizing headaches from migraines and other causes often turn to brain scanning when they don’t get what they really want from doctors. “Actually, they want effective treatment, not scanning,” says Dr. Egilius Spierings, a neurologist at Harvard-affiliated Brigham and Women’s Hospital.
Some primary care doctors don’t know enough about the most effective treatments for migraine and other headaches, says Dr. Spierings. That means some people who have migraines don’t get the medications they need, or aren’t given enough information about how best to use them.
“The focus should be on getting effective relief when you have a headache,” says Dr. Spierings, medical editor of Headaches: Relieving and preventing migraine and other headaches, a Harvard Medical School Special Health Report. “If people get the right treatment, meaning the one that works for them, doctors don’t feel the need to do any neuroimaging.”
Scans for headaches
To get a handle on how many people with severe headaches get CTs and MRIs, Michigan researchers scrutinized data from the National Ambulatory Medical Care Survey on physician office visits. They tallied more than 50 million headache visits made from 2007 to 2010, about half of them for migraine. Brain scans were done about 12% of the time. The cost of these scans to the healthcare system was $3.9 billion ($1.5 billion for migraine-related scans).
Excessive brain scanning costs more than just dollars. Repeated CT scans expose you to enough x-rays to raise the risk of cancer down the road. Scans also tend to lead to more scanning if the test turns up something strange, even though many of these incidental findings turn out to be nothing especially dangerous. Out of all the brains scans done for headache, perhaps 1% to 3% will reveal something abnormal. And most of these “abnormalities” aren’t something to worry about, like a tumor or a bleeding artery in the brain.
Overuse of brain imaging for headaches is not exactly a news flash in the medical profession. In fact, the American Board of Internal Medicine’s Choosing Wisely campaign discourages neuroimaging for “uncomplicated” headaches. To do its part, the American College of Radiology included “Don’t do imaging for uncomplicated headache” on its list of five procedures that doctors and their patients should think twice about.
Yet the use of headache-related brain scans is on the rise. In their JAMA Internal Medicine paper, the researchers reported that headache-related brains scans increased from 5% of headache visits in 1995 to 14.7% in 2010.
What drives the continued overuse of brain imaging, despite experts’ urgings? In part, it comes from a need to rule out rare but dangerous causes of headache when the usual tools fail to do that.
“If you go to the doctor with a bad headache a couple of times, and the doctor has given you a few drugs but the headache doesn’t get any better, you and the doctor will start worrying that this headache is from something else,” Dr. Spierings says. “If it’s not possible to rule out structural problem in the brain, then it’s an easy step to order an MRI.” Insurers usually pay for these scans, too—even though the vast majority of headaches aren’t caused by a tumor or other serious brain problem.
Migraine standard of care
Many people who consult their primary care doctors because of severe and recurrent migraine headaches don’t actually get what they need—no pain, says Dr. Spierings.
Drugs called triptans can stop the headache within two hours, provided the drug is taken when the headache is still mild. If it doesn’t stop within two hours, you may need to take more medication. Later on, other medications can be taken to help prevent future attacks.
It’s important to take migraine medicine as directed. “With migraine treatment you always need to treat right away, you have to make sure the dose is high enough, and you always have to repeat two hours later if the headache is not fully gone,” says Dr. Spierings.
You can live free of headache pain!
Check out Harvard Medical School ‘s guide to relieving and preventing migraines and other headaches
Of course, all of these drugs have potential side effects, and the pros and cons should be weighed carefully. But they work for many people if they are used properly, Dr. Spierings emphasizes.
When to see a doctor
Headaches come in three varieties: Tension, sinus, and migraine. More than 95% of headaches aren’t caused by an underlying disease or structural abnormality. Instead, they spring from common conditions such as stress, fatigue, lack of sleep, hunger, changes in estrogen level, weather changes, or caffeine withdrawal. Most people don’t need a doctor visit or a brain scan. Instead, they need over-the-counter pain relievers (such as aspirin, acetaminophen, ibuprofen, and naproxen) or prescription medications, rest, and relaxation.
If you find yourself taking painkillers for headaches more than a couple of times a week, see your doctor. Red flags that signal the need for medical evaluation include:
I’ve spent the past three days at the 65th annual meeting of the American College of Cardiology in Washington, DC. Cardiologists from around the world are gathered here to present new research on heart disease. During the opening lecture, Dr. Gary Gibbons, director of the National Heart, Lung, and Blood Institute, described a phenomenon I’ve heard a lot about recently from physicians I’ve interviewed in my role as executive editor of the Harvard Heart Letter: the challenge of success.
What does that mean? Since 1950, death rates from cardiovascular disease have plummeted by 70%, thanks to two major trends. One is the decline in smoking and improvements in cholesterol and blood pressure. The other is the boom in new therapies, including better medications, surgeries, and high-tech procedures to repair an array of heart problems.
The challenge today is finding a new drug or procedure that raises this already high bar. “If you want to test a new drug and show that it makes a difference, you have to compare it to the standard of care,” says Dr. Jorge Plutzky, director of the Lipid/Prevention Clinic and co-director of preventive cardiology at Brigham and Women’s Hospital and a faculty member at Harvard Medical School. The standard of care might include up to five different medications, all of which already lower heart attack rates. This high standard may help explain why several major trials presented at the conference failed to show a benefit.
Following is a brief summary of two such studies — and two with positive results — that generated buzz among experts at the meeting. All were published online today in The New England Journal of Medicine.
Procedure for stubborn high blood pressure loses luster
A procedure that doctors hoped might help people with hard-to-control high blood pressure failed to live up to its earlier promise. Called renal denervation, it involves threading a thin wire (catheter) into the arteries that supply the kidneys. A tiny device at the catheter’s tip delivers bursts of energy that damage some of the nerves supplying the kidney, which is involved in blood pressure regulation. But in a carefully controlled trial, whose participants were taking at least three drugs to control their blood pressure, renal denervation proved no more effective than a sham procedure. Still, study leader Dr. Deepak Bhatt of Harvard-affiliated Brigham and Women’s Hospital (and medical editor of the Heart Letter) says he remains cautiously optimistic about renal denervation, which remains an investigational procedure in the United States.
No benefit from a targeted treatment to lower heart attacks
Another trial tested a novel drug called darapladib, which was designed to lower blood levels of a fat and protein particle known as LP-PLA2. Higher blood levels of LP-PLA2 have been linked to a higher risk of heart attacks and related problems. For the trial, more than 15,000 people with stable heart disease took either darapladib or a placebo — along with a statin to lower cholesterol and other heart disease medications.
During the follow-up, which lasted just over three and a half years, roughly the same number of people in both the placebo and treatment groups had a heart attack or stroke, or died from cardiovascular disease. In other words, darapladip didn’t do much.
Lowering cholesterol with a once-a-month injection?
In the “promising-but-still-preliminary” realm is an injectable drug called evolocumab that slashes levels of harmful LDL cholesterol by more than half. It belongs to a class of drugs called PCKS9 inhibitors that work by boosting the liver’s ability to clear LDL from the blood. In a year-long trial, participants used a pen-like device to inject evolocumab once a month. Some took the drug alone, with changes in diet. Others took it in addition to a statin or other cholesterol-lowering drug. In all groups, evolocumab dramatically lowered LDL. A separate study of evolocumab showed similar LDL reductions in people unable to take a statin due to intolerable side effects.
But just because evolucumab lowers LDL doesn’t mean it prevents heart attacks or lowers the risk of dying of heart disease. “The proof of the pudding is long-term outcome studies to show safety and efficacy,” said Harvard professor Dr. Peter Libby, chief of cardiovascular medicine at Brigham and Women’s Hospital, during a press briefing about the research. Those studies are underway, with results expected in several years. Also worth noting: while generic statin medications cost very little, the newer drugs are likely to be very expensive.
Replacing faulty aortic valves without surgery
For older adults with a stiff, failing aortic valve, a procedure known as transcatheter aortic valve replacement (TAVR) offers a less-invasive option than open-heart surgery to replace the valve. TAVR delivers the new valve to the heart through a catheter threaded into an artery in the groin and then carefully maneuvered into the heart. TAVR is currently approved only for people considered too sick or frail for valve replacement surgery. Early tests of TAVR had found that people who underwent the procedure recovered faster but faced a slightly higher risk of stroke than those undergoing open-heart surgery. The new study presented at the ACC meeting found a lower risk of stroke in the TAVR group than in the surgery group. People who received TAVR were also more likely than people who had open-heart surgery to be alive one year later, adding further support for the technique.