The mind/body connection in health and illness has been the subject of a tremendous amount of research and public interest. Studies and articles receive considerable attention in the medical, psychology and lay press because of the popular belief in such a connection, and in mind/body interventions as a means to prevent or cure conditions such as hypertension.
Over decades, thousands of studies funded by hundreds of millions of National Institutes of Health dollars have been performed. It is long past time to ask: What has this enormous body of research taught us regarding the understanding or treatment of hypertension? Should further money be poured into mind/body research in hypertension? In this two-part blog, I will address these questions, based on what research tells us, and based on my own research and clinical experience.
It is clear that in most cases, genetic factors and health habits (diet, weight, salt intake, lack of exercise) are the major contributors to hypertension. In my professional estimation, about 40 percent of hypertension is attributable to genetic factors, and another 40-50 percent to health habits. Healthy diet and exercise have been consistently shown to lower blood pressure. In some they normalize blood pressure, but in many they don't, either because of genetic factors that don't respond to these measures, or because of inadequate adherence to healthy habits. Here, medications will usually do the job, and, in fact, 50 of the 75 million Americans with hypertension are taking medication.
What, then, is the role of psychological factors? Psychological studies in hypertension focus on identifying psychological causes, but not on the proportion of hypertension that is attributable to psychological factors. My research and experience suggest that psychological factors do not play a major role in most cases, but are very relevant in about 10-15 percent, and that research attention should be focused on that 10-15 percent and not on everyone with hypertension.
A key question is: What is the nature of the mind/body connection? Many believe, and thousands of studies have been performed to prove, that factors such as anxiety, anger and day-to-day stress lead to development of hypertension. The psychosomatic paradigm was straightforward: These factors elevate our blood pressure again and again, leading ultimately to sustained vascular effects and hypertension. The corollary to this is that relaxation and stress-reduction techniques could prevent the development of hypertension.
However, a half-century of research has failed to prove that any of this is true! Yes, there are occasional studies that find a link, but most don't. More importantly, as I summarize in my book Hypertension and You, reviews and meta-analyses conclude that decades of studies have failed to prove that anger or anxiety or day-to-day stress cause, or lead to, hypertension, or that stress-reduction techniques are helpful in treating hypertension. It is long past time to finally accept that this paradigm is wrong, instead of throwing more money to keep on trying to prove that it is right. Yes, depression, hostility and anxiety have been shown to contribute to coronary heart disease, and to make us miserable, but they have not been shown to cause hypertension.
If day-to-day stress were a major cause of hypertension, job stress would be a prime candidate. But here also, in a review of studies of job stress that I published several years ago, most studies did not find job stress to be linked to development of hypertension. Indirectly, it can; if someone abuses alcohol or overeats and gains weight as a result of stress, yes, that could lead to hypertension. But stress per se is not a direct cause.
If day-to-day stress, anger and anxiety don't cause hypertension, why do so many people believe that they do? Two important reasons: First, there is no doubt that, in the moment, they do transiently raise our blood pressure. Not only in people with hypertension, but in all of us. If we feel anxious, our blood pressure goes up in the moment, but that is not hypertension, and does not lead to hypertension. And relaxation techniques, biofeedback, etc. absolutely do lower blood pressure in the moment, but don't have lingering effects. (Yes, if you could practice biofeedback all day, it would!) Second, if you are anxious when a doctor checks your blood pressure, the reading will be elevated in that moment, leading to a false diagnosis of hypertension, and a false impression that anxiety is causing the hypertension. Anxiety is causing the temporary increase in blood pressure, but you might not have hypertension.
My experience treating thousands of patients with hypertension is consistent with this. I see many patients whose blood pressure is elevated in my office, and who were told that they have hypertension and are on medication for it. They assume that anxiety is the cause of their hypertension when in fact many of them don't have hypertension, and shouldn't be on medication. In them, monitoring the blood pressure at home is crucial in ascertaining what their blood pressure really is.
So if day-to-day stress and anger and anxiety are not causes of hypertension, do I believe that there is a mind/body connection in hypertension? Yes, I absolutely do. But the connection is very different from what most people think. And determining whether your hypertension is driven by emotion is important because if it is, your hypertension might require different treatment and blood pressure medication than in the usual case. In the next blog I'll discuss what my work tells me about the mind/body connection in hypertension, discuss research that supports that view, and convey how you can determine whether psychological factors might be relevant to your hypertension, and to choosing the blood pressure medication that is right for you.
For more by Samuel J. Mann, M.D., click here.
For more on personal health, click here.