Andrea Evers leads an innovative, groundbreaking research programme into the influence of psychological factors on physical symptoms and disorders. Evers is a world expert in the area of placebo effects and translates new scientific insights into self-help tools, which enable people to better deal with a disorder or to live a healthier life. She is Professor of Health Psychology at Leiden University. In 2019, she received the Stevin Prize of 2.5 million euros.
You were born in Germany. How did you end up in the Netherlands?
‘I was visiting Amsterdam and entered the beautiful Felix Meritis building. I instantly felt that it would be a fantastic place to study; a place where old knowledge and traditions were combined with an innovative learning environment. I was also really impressed by the approach and international orientation of Dutch research. Funnily enough, my great grandmother moved from Amsterdam to Germany, but I only discovered that later.’
Why do you find health psychology so fascinating?
‘I've always been fascinated by the interaction between psychology and medicine. Our thoughts, feelings and behaviour constantly influence our body. Conversely, our body exerts a large influence on how we feel. At first, I did not know whether I wanted to study medicine or psychology because it was that interaction that interested me so much. So I asked myself: which is worse, losing a leg or not being able to cope with a lost leg? With that in mind, I chose psychology, but always with the approach of unravelling the interactions between the mind and the human body.’
‘A second important motivation was the desire to implement my insights in practice. So it is really helpful that everybody finds my discipline about the relationship between mind and body so interesting. Every journalist and person who visits our department starts talking about their own experiences or those of somebody in their family within ten minutes, and there is so much recognition for what we do. I also get many reactions at the lectures I give to professionals. But having said that, many challenges remain. Psychology and medicine often still work independently of each other.’
So there is still a lot of ground to gain?
‘Yes, there is. Simply looking beyond the boundaries of one’s own discipline can have a considerable impact. Within medicine, there is all too often still an overemphasis on prescribing pills. A treatment's success is frequently put down entirely to the drug, even though research has revealed that for many drugs, such as antidepressants, that is only true for a limited part of the drug effects. A patient's expectations and the trust in his or her doctor play a crucial role in this.’
How do placebos influence the body?
‘A placebo effect can elicit a wide range of physical changes. We now know far more about the underlying neurobiological mechanisms. In the professional literature, placebos appear to play a role in nearly all treatments, and some placebo operations have been described too, for example, for people with knee osteoarthritis. In half of the study subjects, no intervention took place. Nevertheless, these patients recovered just as well as people who had undergone the operation. Conversely, people who receive information about the possible side effects of chemotherapy or other medicines can actually experience physical symptoms from only being informed about these side effects. We refer to that as the nocebo effect.’
‘In 2017, in my capacity as chair of the Society in Placebo Studies (SIPS), I organised a world conference in Leiden about placebo treatments, and in July of this year, we will hold the next conference on this subject. Together with the best international researchers in this field, we held an expert meeting during which guidelines were developed for how medical practitioners can best deal with placebo and nocebo effects in practice. This year we will continue on this process in a second expert meeting.‘
What will the guidelines look like?
‘We must ensure that health practitioners are better informed about the existence of these effects and about how these can best be used. It should be investigated whether patients actually support the treatment prescribed. Do they really understand the purpose of the treatment, how it works and why something has been prescribed? What are their long-term expectations? Can the practitioner optimise those expectations in an ethical way? Are they scared of risks and side effects, and can the health practitioner remove those anxieties by providing a more detailed explanation? Optimising placebo and decreasing nocebo effects can make a huge difference to the treatment outcome.’
‘We now know that the patient does not remember most of the conversation in the consultation room. Communication training courses could help doctors and other care providers. Why does someone want to undergo this treatment? Not because their doctor tells them to, but because they want to be able to play with their grandchildren later in life! If there is not enough time during the consultation to properly motivate people, then perhaps nurses could play an additional role in this. For a small group of particularly worried patients, we could always call upon the services of a medical psychologist. Making optimal use of placebo effects yields a health benefit.’
‘Furthermore, I see highly promising opportunities to optimise treatments with drugs. The most important principle for placebo effects is conditioning. That conditioning principle can be applied to the drug dosage. Research has revealed that various physiological systems in the body, such as the immune system or the production of certain hormones, can be conditioned so that the body produces the substances administered. That could eventually lead to a lower dosage being administered. Several studies provide cautious indications that this approach could be highly promising.’
You develop apps and E-health applications. Do you expect a lot from these?
‘Yes, I do. I am not just a researcher, but also a clinical psychologist, and I have developed many treatments that we offer at our Leiden University Treatment Centre (LUBEC). Besides cognitive behavioural therapies to teach patients how to cope with physical disorders, I have focused on digital methods. E-health fits in our current culture and has also proven to be effective at influencing conscious and subconscious behaviour. It also appeals to younger people. We use e-coaching and serious gaming to enable people to deal with the symptoms of disorders as well as possible, especially in the case of chronic illnesses, but also to encourage a healthy lifestyle. Oddly enough, standard healthcare is not particularly focused on empowerment and prevention, even though people really want this. That is what makes this research so fantastic and gratifying: it puts people first.’
You took the initiative to realise a large consortium in which care providers, civil society partners and researchers jointly work for a healthy lifestyle. How do you tackle that?
‘In our national consortium “Benefit for all”, people are rewarded for healthy behaviour. In our society, but also in how we are raised as children, we are strongly trained and conditioned to find unhealthy things pleasant. There is an incredible supply of unhealthy food, and from a biological and evolutionary perspective, our bodies are also designed to eat as much as possible. Merely looking at tasty food stimulates the reward systems in our brain. So whoever wants to live healthily could do with a bit of support. That is why we developed tools. Until recently, encouraging a healthy lifestyle was mainly about discipline. But in the long-term, particularly in stressful situations, this approach is not in the slightest bit appealing. A far better approach is to make healthy living fun. We must literally reward people for every type of healthy behaviour. Not just the outcome but simply for the fact that they are acting healthily and doing their best. Feedback by a coach or earning points for keeping a food diary or using a activity meter are just some of the many possibilities how people can be motivated.’
‘In the consortium, we are working together with organisations in the field of cardiovascular diseases, but we want to roll out the programme in far more areas. A lot of research is still needed into what works for whom. What works for an academic might not work for people with fewer qualifications. As a researcher, you can best consult the users: what do they experience as a reward? Behavioural changes are complex, but the interest in this has increased considerably in a short space of time, and my research fits perfectly within this.’
What do you plan to do with the Stevin Prize?
‘I've always wondered how you can make a real difference with your research by making new connections. And that is precisely what the Stevin Prize is about. So I will use the prize to make new connections. For example, I would like to encourage interdisciplinary research with a clear emphasis on connecting fundamental research with clinical applications. I'm also convinced that we can mainly generate impact by collaborating with other parties outside of science, which is what our consortium for healthy living does. I hope that receiving the Stevin Prize will make a real difference in this regard. I find it enormously encouraging that I can now continue to work at twice the pace on making new connections between science disciplines but also with society and arts. I think that I am a genuine lifelong bridge builder.’
Text: Marion de Boo, photography: Studio Oostrum/Hollandse Hoogte