Why the placebo effect is rewriting the medical rulebook

Why the placebo effect is rewriting the medical rulebook

New Science Publications Editorial– Editor Jeremy Webb Personal Asst & Office Manager Anita Staff Associate Editors Liz Else, Stephanie Pain News Ed...

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New Science Publications

Editorial–

Editor Jeremy Webb Personal Asst & Office Manager Anita Staff Associate Editors Liz Else, Stephanie Pain News Editor Shaoni Bhattacharya Editors, Helen Knight, Celeste Biever, Richard Fisher, Sumit Paul-Choudhury, Priya Shetty Tel +44 (0) 20 7611 1206 Fax +44 (0) 20 7611 1250 Reporters LONDON Andy Coghlan, Paul Marks, Linda Geddes, David Shiga [email protected] BOSTON US Bureau Chief Ivan Semeniuk SAN FRANCISCO Bureau Chief Peter Aldhous [email protected] Jim Giles [email protected] TORONTO Alison Motluk BRUSSELS Debora MacKenzie MELBOURNE Australasian Editor Rachel Nowak [email protected] Features Editors Ben Crystall, Kate Douglas, Clare Wilson, David Cohen, Graham Lawton, Valerie Jamieson, Michael Le Page, Caroline Williams Features Assistant Celia Guthrie Tel +44 (0) 20 7611 1201 Fax +44 (0) 20 7611 1280 [email protected] Opinion Editor Jo Marchant Editors John Hoyland, Amanda Gefter, Alison George, Eleanor Harris Tel +44 (0) 20 7611 1240 Fax +44 (0) 20 7611 1280 [email protected] Researcher Lucy Dodwell Editorial Assistant Amy Galloway Production Editor Mick O’Hare Asst Production Editor Melanie Green Chief Sub John Liebmann Subeditors Vivienne Greig, Julia Brown, Sean O’Neill Art Director Alison Lawn Design Craig Mackie, Ryan Wills Graphics Nigel Hawtin, Dave Johnston Pictures Adam Goff, Kirstin Jennings Tel +44 (0) 20 7611 1268 Fax +44 (0) 20 7611 1250 Careers Editor Helen Thomson [email protected] Tel +44 (0) 20 7611 1248 Fax +44 (0) 20 7611 1280 Consultants Alun Anderson, Stephen Battersby, Michael Bond, Michael Brooks, Marcus Chown, Rob Edwards, Richard Fifield, Barry Fox, Mick Hamer, Jeff Hecht, Bob Holmes, Justin Mullins, Fred Pearce, Helen Phillips, Ian Stewart, Gail Vines, Gabrielle Walker, Emma Young, Anil Ananthaswamy Press Office and Syndication UK Claire Bowles Tel +44 (0) 20 7611 1210 Fax 7611 1250 US Office Tel +1 617 386 2190 NEWSCIENTIST.COM Online Publisher John MacFarlane Online Editor Will Knight Editors Maggie McKee, Rowan Hooper, Tom Simonite Reporters Catherine Brahic, Colin Barras, Sandrine Ceurstemont, Michael Marshall, Ewen Callaway, Rachel Courtland Online Subeditor Dan Palmer Web team Neela Das, Cathy Tollet, Ruth Turner, Ken Wolf, Edin Hodzic, Vivienne Griffith, Rohan Creasey, Matteo Giaccone

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Patient, heal thyself There’s more to a drug than the chemicals in the pill THE placebo effect has been known about since the beginnings of medicine. Indeed, it used to be just about the only medicine doctors could offer their patients – reassurance that a treatment will work, with the result that it often did. What nobody realised until recently is just how powerful and complex the effect is. It turns out that a patient’s state of mind, awareness of their condition and expectations of the care they are about to receive can influence pretty much every facet of medicine, from consultations with a doctor to clinical trials of a new drug. For example, one set of researchers has found that the anxietyrelieving drug diazepam doesn’t work unless patients know they are taking it. Similarly, morphine is significantly more effective when people are told they are being given it. In both cases the placebo effect is critical to the drug’s effectiveness (see page 36). The potency of the placebo effect can be a boon for doctors, especially when faced with patients whose symptoms do not respond to any known treatment. One survey found that nearly half the physicians in the US consciously use the placebo effect in their prescribing. Fewer than half of these tell the patient what they are doing, fearing that if they did the placebo wouldn’t work. Is this kind of deception acceptable?

Many think it is, so long as it helps the patient. Still, deception may not always be necessary: a study earlier this year showed that a placebo can work even when the patient is aware they are taking it. Children with attention-deficit hyperactivity disorder can manage just as well on a lower dose of medication if they also take what they are explicitly told is a “booster” capsule, which “has no drug in it… but it may help you to help yourself”. Given that many drugs have nasty side effects, this kind of “open label” use has obvious potential. But there is a flip side, as this all has implications for the way clinical trials are done. Given the many and complex ways in which people respond to placebos, the standard idea of discovering the effectiveness of a drug by testing it against a “sugar pill” now looks a little simplistic. Clinical trials may have to become more sophisticated: for example, by disguising when a drug treatment starts or ends, or telling some participants that they received the drug when they actually got the placebo. Again, these methods involve a degree of deception, and the ethics of that will have to be thrashed out. What’s clear is that the usefulness of a drug, for example, depends on a lot more than the chemicals in a pill, and that a deeper understanding of the placebo effect could turn it into an invaluable tool for reducing suffering. ●

Stem cell therapy takes a giant leap IT HAS been 10 frustrating years since human embryonic stem cells were first isolated from spare human embryos and grown in the lab – frustrating, because ESCs have completely failed to live up to their promise of providing an inexhaustible source of transplantable tissues and organs. Instead, they have remained mired in moral and political controversy because they are obtained from embryos that perish in the process. Only one company, Geron of Menlo Park, California, has made significant progress on the medical front, having successfully turned ESCs into cells that could be used to repair spinal cords, hearts, livers, bones and pancreases. Unfortunately its most advanced plans for a clinical trial – to treat damaged spinal cords – keep getting rebuffed by the US

Food and Drug Administration, most recently in May. The FDA is not satisfied that the cells will be safe. Will patients’ immune systems react against them? Will they turn cancerous? Now, at long last, researchers have managed to turn ESCs into something with obvious practical potential: an inexhaustible supply of red blood cells. A supply that, in future, could be transplanted into anyone, irrespective of their blood type (see page 10). Like true red blood cells they don’t have nuclei, so they cannot multiply and cause cancers. There is still work to do to create truly “universal” cells and ensure they work in animals and people. But it is an important breakthrough, and a timely response to those in the US trying to turn the use of cells from embryos into an election issue. ● 23 August 2008 | NewScientist | 5