ESPEYB15 14 Science and Medicine The ‘nocebo’ effect: psychogenic but truly harmful (1 abstracts)
National Heart and Lung Institute, Imperial College London, London, UK
To read the full abstract: Lancet 2017;389:2473-2481
We are all familiar with the ‘placebo’ effect, when the psychological anticipation of a ‘benefit’ of treatment is so strong that it adds to or even outweighs the actual physical benefits. Many doctors have even admitted to prescribing placebo tablets, or “sugar pills” to their patients, for example for pain relief in irritable bowel syndrome. Such practice is not illegal, but it does raise ethical concerns issues regarding lack of openness between doctor and patient.
Here, Gupta et al. provide convincing evidence for the ‘nocebo’ effect. This occurs when the psychological anticipation of ‘harm’ related to a treatment is so strong that it augments the actual physical harm. Statins cause myopathy in ~1:10,000 patients per year, including one reported case of non-fatal rhabdomyolysis. However, the authors describe “the widespread media coverage that has arisen from claims that statin therapy causes side-effects in up to one fifth of patients” has caused patients to overestimate the harms of statin treatment. This was robustly shown by this large study, which found an excess of muscle-related statin adverse effects only during the open (non-blinded) phase of the trial (hazard ratio = 1.41; p=0.006), but not while the treatments were blinded (hazard ratio 1.03; p=0.72). The authors discuss that such nocebo effects can cause real harm, by dissuading many patients from continuing on effective treatments, resulting in thousands of otherwise avoidable cardiovascular disease events. We need to be aware of, and make efforts to dispel, untrue lay beliefs about our treatments.