Antidepressants Not Very Effective for Mild Depression
A new study shows that sugar pills work about as well, except in people with very severe depression.
By Deborah Kotz, U.S. News & World Report
If you think you need an antidepressant because "things just don't feel like they used to,"―as a TV ad for the antidepressant Zoloft describes it―you might want to think again. A new study published in the Journal of the American Medical Association finds that the medications work no better than a placebo in those with mild or even moderate symptoms of depression. The drugs are, however, very effective at lifting depression in people with very severe symptoms. "Consumers may not be aware that the efficacy of [these] medications largely has been established on the basis of studies that have included only those individuals with more severe forms of depression," the study authors write.
Unfortunately, primary care physicians who prescribe antidepressants often don't take the time to tease out the very severe cases from the milder ones, says study co-author Robert DeRubeis, a professor of psychology at University of Pennsylvania. "Those with severe symptoms typically wake up every morning one to three hours before they want to," he explains, "often wish they were dead, have a marked increase or decrease in their food intake, and a major decrease in their productivity at work if they can get to work at all." Those with milder symptoms, on the other hand, may have some noticeable sleep difficulties (but not every night), have feelings of dread (but not thoughts of suicide), and can still get their work done even when feeling down. Sure, these folks may feel better after taking an antidepressant, but they might have also felt better just going to the doctor to discuss their symptoms, hitting the gym for regular workouts or making time to socialize with friends.
"A longer life or better life is what you hope for when you take a medication," says Lisa Schwartz, an associate professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice. Before filling that new prescription, she advises, "find out whether this premise is really true or based on a set of assumptions." Most antidepressant trials, DeRubeis says, only included patients with severe or very severe depression, and the beneficial results measured don't apply to those with mild cases. Clearly, medications can be lifesaving for some (the heart-disease patient taking a statin to prevent another heart attack) and life-altering for others (that severely depressed person finally able to get out of bed). But you may not need a statin if your cholesterol is just a tad high or an antidepressant if you're feeling down over a bad breakup. Here are the five questions to ask your doctor to help you determine whether to take that oh-so-promising pill.
1. Why am I getting this drug?
Place the emphasis on the "I" when asking this question. Your doctor should consider your personal risk factors when prescribing a drug―not the last patient he treated who may have been helped enormously by the drug but also may have been far sicker to begin with. If you're considering a cholesterol-lowering drug, for instance, ask, "Has this drug been shown to prevent real clinical events like heart attacks or strokes in patients my age and gender with a cholesterol profile like mine?" says Jerry Avorn, a professor of medicine at Harvard Medical School and author of Powerful Medicines. Ditto for bone-building drugs, which are being given more and more frequently to those with some bone loss, called osteopenia, but not full-blown osteoporosis. Ask, Avorn says, "Will this drug prevent fractures in those with bone measurements like I have?"
2. What are the risks versus the benefits?
Your doctor should be able to tick off the side effects of any drug she's prescribing as well as serious adverse events associated with them and how commonly those occur, says Schwartz. You should also have a clear understanding of the benefits. Even in severe cases of depression, antidepressants significantly help one-third of patients who take them, mildly help another third and don't do much good for an additional third―information that's become known in research studies but isn't featured prominently on manufacturer's Web sites. Schwartz and her colleagues at Dartmouth/VA Outcomes Group would like the FDA to begin offering consumer-friendly information on the risks and benefits of every drug they approve and are working with the agency to develop drug graphics like this one for Lunesta.
3. Is there an older drug or lifestyle alteration that works just as well?
Every time your doctor accepts a free lunch, fruit basket, heck, even ballpoint pen from a drug maker, you can bet that it's for a drug that's new, expensive and still on patent (which means there's no cheap generic available). "There's no question that doctors are more likely to prescribe drugs that they're being lobbied on," says Avorn, "new ones being heavily marketed by pharmaceutical firms." The trouble with a new medication? "We might not know its long-term benefits or its track record for risks," explains Schwartz. "It's one thing if there's no other treatment available for your condition, but it's quite another if there are a lot of other treatments that have stood the test of time." She says if your doctor can't make a strong case for why a new treatment may be better, take the older one. Ditto for lifestyle changes. For those with mild depression, exercise can work just as well as an antidepressant. Salt-sensitive folks with high blood pressure may be able to reduce hypertension simply by lowering their sodium intake. And many of those with type 2 diabetes can reverse their condition by losing weight, increasing their activity and cutting back on carbohydrates.
4. Will it interfere with other medications I'm taking?
While one-fifth of Americans have taken three or more chronic drugs in the past year, many of them get their prescriptions from different specialists who are supposed to check for medication interactions but often do not. Pharmacies also alert you to dangerous drug-drug interactions, but this may not happen if you don't get all your medications from the same place. Also, it's important to factor in all those over-the-counter medications you may be on like acid blockers, allergy medications or pain relievers.
5. Has this drug been shown to prevent real clinical events?
You might think that any drug approved by the FDA would have to meet that criteria. But that's not the case. The diabetes drugs Avandia and Actos, for example, were approved "to help improve blood sugar control in adults with type 2 diabetes." These drugs don't, though, actually prevent heart disease, the leading killer of diabetics. "It's not enough to show that a drug lowers blood sugar; does it in fact improve clinical outcomes and not cause harm?" says Steven Nissen, head of cardiovascular medicine at the Cleveland Clinic, who published a study two years ago showing that Avandia was associated with an increased risk of heart attacks and deaths from heart disease. He and the other experts who spoke with US News would like to see the FDA only approve new drugs that clearly show a benefit to the patient, rather than just improving lab test measurements like cholesterol, blood sugar and bone density scores. Schwartz sums it up this way: "Your doctor should be able to explain why you're taking this drug right now. Will it make you feel better? If not, will it prevent something bad from happening in the future? How big is the chance that you'll actually experience that bad outcome if you don't take this drug?"
More on Depression on MSN Health & Fitness:
* Why Do Antidepressants Make Me Nervous?
* Can Antidepressants Lose Effectiveness Over Time?
* Jogging: Antidepressant Substitute?
* Bing: Antidepressants That Cause Weight Gain
Antidepressant Drug Effects and Depression Severity
A Patient-Level Meta-analysis
Jay C. Fournier, MA; Robert J. DeRubeis, PhD; Steven D. Hollon, PhD; Sona Dimidjian, PhD; Jay D. Amsterdam, MD; Richard C. Shelton, MD; Jan Fawcett, MD
Context Antidepressant medications represent the best established treatment for major depressive disorder, but there is little evidence that they have a specific pharmacological effect relative to pill placebo for patients with less severe depression.
Objective To estimate the relative benefit of medication vs placebo across a wide range of initial symptom severity in patients diagnosed with depression.
Data Sources PubMed, PsycINFO, and the Cochrane Library databases were searched from January 1980 through March 2009, along with references from meta-analyses and reviews.
Study Selection Randomized placebo-controlled trials of antidepressants approved by the Food and Drug Administration in the treatment of major or minor depressive disorder were selected. Studies were included if their authors provided the requisite original data, they comprised adult outpatients, they included a medication vs placebo comparison for at least 6 weeks, they did not exclude patients on the basis of a placebo washout period, and they used the Hamilton Depression Rating Scale (HDRS). Data from 6 studies (718 patients) were included.
Data Extraction Individual patient-level data were obtained from study authors.
Results Medication vs placebo differences varied substantially as a function of baseline severity. Among patients with HDRS scores below 23, Cohen d effect sizes for the difference between medication and placebo were estimated to be less than 0.20 (a standard definition of a small effect). Estimates of the magnitude of the superiority of medication over placebo increased with increases in baseline depression severity and crossed the threshold defined by the National Institute for Clinical Excellence for a clinically significant difference at a baseline HDRS score of 25.
Conclusions The magnitude of benefit of antidepressant medication compared with placebo increases with severity of depression symptoms and may be minimal or nonexistent, on average, in patients with mild or moderate symptoms. For patients with very severe depression, the benefit of medications over placebo is substantial.
Author Affiliations: Departments of Psychology (Mr Fournier and Dr DeRubeis) and Psychiatry (Dr Amsterdam), University of Pennsylvania, Philadelphia; Departments of Psychology (Dr Hollon) and Psychiatry (Dr Shelton), Vanderbilt University, Nashville, Tennessee; Department of Psychology, University of Colorado at Boulder (Dr Dimidjian); and Department of Psychiatry, University of New Mexico School of Medicine, Albuquerque (Dr Fawcett).
|<< 前記事(2010/01/06)||ブログのトップへ||後記事(2010/01/08) >>|
|<< 前記事(2010/01/06)||ブログのトップへ||後記事(2010/01/08) >>|