Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Placebos and the Placebo Effects What they are and why we should love them © Heidi Most, M. Ac, L.Ac, Dipl Ac (NCCAOM) Your body’s ability to heal is greater than anyone has permitted you to believe. “Always the purpose of treatment is only to restore nature’s balance against disease. There is no recovery unless it comes from the force and fiber of one’s own tissues.” Dr. Sherwin Nuland, Yale University School of Medicine, Cliinical Professor of Surgery Purpose of this lecture Learn that the context in which treatment is given, and the patient’s and the practitioner’s beliefs, play a major role in the patient’s response to treatment Change the question of concern from “are placebos ethical?” to “how can we make our treatments most effective.” Why is this important? We want to be the best clinicians possible Given the crisis in health care costs, we need to be including all possible methods of increasing effectiveness without increasing cost. Definition of placebo? What is the placebo effect? Working definitions Placebo: “An intervention designed to simulate medical therapy that at the time of use is believed not to be a specific therapy for the condition for which it is offered. Placebo Effect: “A change in a patient’s illness attributable to the symbolic import of a treatment rather than a specific pharmacologic or physiologic property. Brody H. Placebos and the Philosophy of Medicine. Clinical, Conceptual, and Ethical Issues. Chicago: University of Chicago Press, 1980 How does the placebo effect occur? Psychological mechanisms which contribute: Expectations Conditioning Therapeutic and Social Relationships Motivation Neuro-biological mechanisms Endorphin release Brain changes Expectancy Expectancy Research subjects receive experimentally induced pain and are given a topical placebo cream in the context of two different cues: 1) the cream is inert and will have no effect 2) the cream is a powerful pain killer Verbal cues can manipulate expectations and mediate placebo effects: Analgesic effects (both experimentally and clinically) Changes in motor performance in Parkinson’s disease patients Changes in emotions and brain responses “Expectancy” research: Research on post-operative pain divided patients into three sections 1) 2) 3) Received morphine secretly Received morphine and were told they were Received placebo but told it was a powerful pain reliever Results: Patients who were told they received a pain reliever, whether they actually received it or not, had the same experience as those who secretly received between six and 8 milligrams of morphine. The covert dose had to be increased to 12 milligrams to surpass the effect of the placebo Levine JD, Gordon NC Analgesic responses to morphine and placebo in individuals with postoperative pain Pain, Vol 3, 1981 More “Expectancy” research: Diazepam has no discernible effect on anxiety unless a person knows he is taking it. Luana Colloca, Leonardo Lopiano, Michele Lanotte, Fabrizio Benedetti Overt versus covert treatment for pain, anxiety, and Parkinson's disease The Lancet Neurology, Volume 3, Issue 11, November 2004, Pages 679-684 In double blind studies of anti-depressants, patients often figure out if they are getting the “real drug” by side effects. The worse the side effects, the more effective the drug. Classical Conditioning Classical Conditioning Repeated associations between a neutral stimulus and an active drug can result in the ability of the neutral stimulus by itself to elicit a response characteristic of the drug Responses include changes in hormone secretions and immune response How does a conscious or unconscious thought translate into action? Thinking a thought, believing a belief, causes biological reactions The Limbic System Consists of many different sub-areas, with neuronal connections to each other and especially to the hypothalamus Prefrontal cortex has many connections to it The hypothalamus sends messages to the rest of the body through the ANS and the Endocrine system. Therapeutic and Social Relationships Therapeutic and Social Relationships Results of two randomized control trials with asthma patients and with rheumatoid arthritis patients Active group: patients described a significantly difficult conflict or secret about past traumas to the clinician Control group, patients talked about superficial things Smyth, J., Stone, A., Hurewitz, A & Kaell, A. 1999 Effects of writing about stressful experience on symptom reduction…JAMA 281 1304-1309 Result At the 4 month follow-up, asthma patients who were in the active group showed significant improvements in forced expiratory volume, and those with arthritis showed significant improvements in pain, when compared with their control groups. More relationship research Large RCT showed that a positive consultation by a physician produced 2025% greater improvements in functional conditions compared with a negative consultation. Amount of time spent in consultation was equal. Extensive summaries of this research: Chez, R.A & Jonas, W. 2005 Developing healing relationships: J. Altern. Complementary Med. 11, S1-S2 and Safran, D., Miller, W. & Beckman H. 2006 Organizational dimensions of relationship-centered care: …J. Gen. Intern Med. 21, S9-S15. Neuro-biological mechanisms Neurobiological mechanisms Placebo analgesia: The suggestion that a substance will reduce pain increases the release of endorphins, which make patients feel less pain When given Naloxone, which lock up key opioid receptors, the pain comes back Fields HL, Levine JD. Placebo analgesia- a role for endorphins. Trends in Neuroscience 1984; 7:271-73 Other biological effects: Placebo analgesic effects are inhibited by the peptide CCK Several studies have demonstrated highly specific endogenous opioid-mediated placebo analgesic responses, such as increased opioids in cerebrospinal fluid PET and fMRI show placebo induced brain changes mirror those found in opioid drug administration. The effects are not limited to analgesia Increase in respiratory functioning Decreased heart rate Dopamine release and changes in basal ganglia and thalamic neuron firing in Parkinson patients Can see changes in metabolic activity in the brain in depression and expectation manipulation with addiction Albuterol Trial Double-blind crossover study of 46 patients with asthma Wechsler, M, Kelley J, Boyd, OE, Dutile, S, Marigowda G, Kirsch I, Israel E. Kaptchuk, T. “Active Albuterol or Placebo, Sham Acupuncture, or No Intervention in Asthma, N Engl J Med 2011;365:119-26 4 arms Active treatment (albuterol inhaler) Placebo inhaler Sham acupuncture No intervention Methods Administered one each of the four interventions in random order during four sequential visits (3-7 days apart). Procedure repeated in 2 more blocks of visits for total of 12 visits for each patient Spirometry was performed repeatedly over a period of 2 hours, and patients’ self-reported improvement ratings were recorded Results Albuterol resulted in a 20% increase in FEV1, as compared to 7% with each of the other three interventions Patients reported equal and substantial improvement with the inhaled albuterol, inhaled sham and the sham acupuncture. QuickTime™ and a decompressor are needed to see this picture. QuickTime™ and a decompressor are needed to see this picture. Discussion Findings consistent with meta-analysis involving multiple conditions, where placebos, as compared with nointervention controls had no significant effect on objective measures but did have significant effects on subjective outcomes. Hrobjartsson A, Gotzshe PC. Is the Placebo powerless? An analysis of clinical trials comparing placebo with no treatment. N.Engl J Med 2001;344;1594-602 Discussion cont’d Findings do not contradict recent lab studies showing that placebo treatment elicits quantifiable changes in neurotransmitters and regionally specific brain activity that influence symptoms. Bifurcation of effects may represent difference between treating disease and treating illness. When is there no placebo effect? Loss of placebo mechanisms reduce therapeutic efficacy In an open-hidden design in Alzheimer’s disease, the placebo component was correlated with cognitive status and functional connectivity between brain regions. The lower the cognition and connectivity the less the analgesic effect, to the point where an increase in dose was required for same level of analgesia. Benedetti F, Arduino C, Costa S, Vighetti S, Tarenzi L, Rainero I, et al. Loss of expectation-related mechanisms in Alzheimer’s disease makes analgesic therapies less effective. Pain 2006 Mar So far, what do we know? Limitations in current research Most have involved lab experiments over short durations with healthy subjects Longer term placebo response has been studied in RCTs; but these rarely include no treatment groups to control for natural history and regression to the mean More research is needed from a basic science, clinical trial and ethical perspectives Some specific placebo research 3 week single blind RCT with IBS patients (n=262)looked at sham acupuncture, sham acupuncture plus supportive patient-practitioner relationship compared to no treatment control. 62% adequate relief (AR) with acu + support 44% AR acu alone 28% AR no treatment Kaptchuk Tj, Kelley JM, Conboy,LA, Davis RB, Kerr CE, Jacobson EE, et al. Components of placebo effect; randomised controlled trial in patients with IBS. BMJ 2008 May 3 Different vehicles of placebo ritual produce different effects Sham acu more effective than pills in ability to function Depending on complaint and length of time administered, different placebos had different effects Different nocebo effects also observed Alternative therapies with elaborate rituals have clinically significant placebo effects Large acu trials in Germany compared acu, sham acu, usual care, and no treatment for migraine, tension HA, chronic LBP, and OA of the knee Verum and sham acu resulted in substantially greater symptom improvement than no treatment and usual care. More on the German studies Positive expectations influenced analgesic responses, doubling the likelihood of positive outcomes. Results lasted one year. Other interesting findings: The larger the pill, the stronger the placebo effect Two pills are better than one Brand name pills are better than generics Capsules are more effective than pills Injections produce more pronounced effect that capsules or pills More interesting findings: Colored pills are more likely to relieve pain than white pills Blue pills help people sleep better than red pills Green capsules work best for anxiety medication Surgery is an extremely powerful placebo Treatment for coronary artery disease in the 1950s (bilateral internal mammary artery ligation BIMAL) was found to be no better than placebo surgery (relief from angina was significant in 7080% of patients in both active and sham treatment At same time as this research, heart lung bypass machine was developed, allowing for coronary artery bypass surgery. Results: Coronary artery bypass surgery has never been tested in a placebo-controlled trial Its effectiveness in treating angina is approximately the same as the old treatment: 70-80% More placebo surgery research Placebo-controlled study of 298 patients with class III or IV heart failure underwent high-dose laser treatment, low-dose laser treatment or placebo (catheter inserted but the laser was never turned on) Equally significant improvement in all groups which lasted over 6 months. Johnson A. 1994 Surgery as placebo. Lancet 344, 1140-1142 More placebo surgery research The placebo “debridement” of osteoarthritis with arthroscopic surgery showed just as good pain relief as actual debridement for the same procedure. Two control conditions: Only laparoscopic lavage was used Skin incision made without insertion of laparoscope Results: Pain relief lasted over 2 years and was equal in all groups. Moseley, J., O’Malley, K., Petersen, N., Menke, T., Brody, B., Kykendall, D., Hollingsworth, J., Ashton, C., and Wray, N. 2002 A controlled trial of arthroscopic surgery for OA of the knee. N. England J. Med 347, 81-88 Placebo effects are inherent in clinical practice, even w/o placebo Hidden administration of 5 commonly used painkillers were markedly less effective than open administration Colloca L, Lopiano L, Lnotte M, Benedetti F. Overt versus covert treatment for pain, anxiety, and Parkinson’s disease. La cet Neurology 2004; 3; Amanzio M, Pollo A, Maggi G, Benedetti F. Response variability to analgesics: a role for non-specific activation of endogenous opiods. Pain 2001; Similar results have been reproduced for drug admin for anxiety and deep brain stimulation for Parkinson’s Disease Another open-hidden paradigm study CCK antagonist proglumide was shown to be better than placebo, which was in turn better than no-treatment for post-operative pain. However, a hidden injection of proglumide was completely ineffective, showing the drug achieved a response by interacting with and enhancing the expectancy pathways. Its effectiveness was dependent on the placebo mechanisms inherent in the clinical encounter. Benedetti F, Amanzio M, Maggi G. Potentiation of placebo analgesia by proglumide. Lancet 1995d The placebo effect is not always present Placebos are not magic They have not been proven to be effective in reducing tumors, changing the course of fatal diseases, reducing extremely high levels of pain… AND we can improve many therapies through using the placebo effect. A short term experiment in 2001, postoperative pain patients took 33% less active analgesic if they believed they were also receiving intravenous analgesia. Pollo A, Amanzio M, Arslanian A, Casadio C, Maggi G, Benedetti F. Response expectancies in placebo analgesia and their clinical relevance. Ain 2001; 93 (1) In IBS study, patients exposed to a painful stimulus under two conditions: local anesthetic and placebo. In one study they were told that they “may receive an active or a placebo agent” and in the second they were told that “the agent you have been given is known to significantly reduce pain in some patients”. Placebo responses were larger in the second study. We have seen expectation and belief strongly influence therapeutic outcomes. In what other unconscious ways is our behavior influenced? Other ways our behavior is unconsciously influenced: Marketing (wine labeled from CA tastes better than wine labeled from IN, even though it is the same wine) Embodied cognition: our rationality is influenced by our bodies (women who wore bikinis did worse on math tests) Enclothed cognition (the clothes we wear influence how we experience the world) How can we maximize the therapeutic effects of our treatments? The definition of treatment needs to be broadened Drugs Surgery What we say How we conduct ourselves The environment in which we work and see patients Therapeutic relationships Reminder: Placebo is an intervention designed to simulate medical therapy that at the time of use is believed not to be a specific therapy for the condition for which it is offered. Important to recognize what we don’t know We do not know the limits of our knowledge, of our own minds “The scientist knows that in the history of ideas, magic always precedes science, that the intuition of phenomena anticipates their objective knowledge.” “Advance in detail is permitted: fundamental novelty is barred. This dogmatic common sense is the death of philosophical adventure.” Gauguelin 1974 Alfred North Whitehead (1948) What we think of as placebos might in fact be proven in the future to have specific therapeutic effects. Acupuncture Reiki Therapeutic touch Bio-feedback What else do we know of that strongly influences therapeutic outcomes? Mindfulness-based Stress Reduction Conscious relaxation reduces the cascade of stress responses, reducing our heart rate, blood pressure, relaxing our bowels, improving digestion, reducing pain in chronic disease, makes learning easier Our immune system responses are improved, we get less colds, miss fewer days of work What are the ethical considerations? If treatments have not been successful, or as successful as you would like, is it ethical to: Recommend acupuncture? meditation? herbal preparations? Bio-feedback? Crystal therapy? What level of information do you need to make a recommendation? Double blind RCTs? How many? Other forms of research? Good friends, family members who have benefited? What level of information is enough? Summary A patient’s expectations, beliefs, conditioning and anxiety can strongly effect treatment efficacy As practitioners, we can strongly affect those expectations through our words, and behavior. We can use the evidence from placebo research in a way that is ethically acceptable and effective. Recommendations Wayne Jonas Replace the term Placebo Effect with concepts such as “meaning and context’ response components in research Create optimal healing environments for all of our clinical care Acknowledgements: “Placebo Effects: Biological, Clinical and Ethical Advances” Damien G Finniss, Ted J. Kaptchuk, Franlin Miller and Fabrizio Benedetti, Lancet. 2010 February 20; “Reframing Placebo in Research and Practice” Wayne B. Jonas, Philosophical Transactions of the Royal Society 2011