Saturday, July 1, 2017

The Nervous Theory Of Asthma: A Review

Earlier, I wrote that “Occupational Asthma” was “one of the oldest asthma subgroups.” I would like to make the case here that the oldest of oldest of oldest asthma subgroups is none other than “Nervous Asthma.” To help me make my case I thought a little history of nervous asthma would prove helpful. 

400 B.C. Hippocrates (400 B.C.) referred to asthma as epilepsy of the lungs. This is because he believed it was caused by phlegm draining down from the brain. He, therefore, believed asthma was caused by airway spasms similar to the body spasms of epilepsy. He also alluded to asthma as a nervous disorder when he said, "the asthmatic should guard himself against his own anger." 

1st Century. Galen (120-200 A.D.) is a physician who created theories about medicine that were well respected by physicians all the way up to the 19th century, and even into the 20th century. He performed one experiment (and probably on a stolen body) where he severed the spinal cord to produce asthma symptoms artificially. (1)
2nd Century.
 Maimonides (1138-1204) said nervousness makes one prone to illness and may have been the first to describe how illness can contribute to diseases. He did describe asthma, but he did not link the two.

1550. Felix Platerus (1536-1614) observed asthma symptoms when nothing wrong could be seen with the lungs. He believed asthma was caused by an obstructed pulmonary artery, although he also believed it was caused fluid flowing down from the larger nerves from the brain.

17th century. Jean Baptiste van Helmont (1579-1644) was the first physician to focus on the idea that asthma was caused by airway spasms. However, he believed this was the result of nerve irritation due to stress. He thought this was the case because no scars were observed in the lungs of asthmatic patients. He gave examples of how stress could induce asthma. In one case he described how a woman developed it just by being exposed to flowers, and in a second case, he described how a man developed it and died just after being exposed to stress.

17th century.  Thomas Willis (1621-1675) also described asthma as having occurred despite any observable changes in the person. Paul Ammann (1634-1691) described in a book of law cases how asthmatics should be absolved from crimes because the fear that resulted could result in an asthmatic attack. This meant that all asthmatics must be kept out of stressful situations.

1850’s. Dr. Henry Hyde Salter published a series of articles that were eventually published in 1960 as “On Asthma: Its Pathology and Treatment.” In these articles, later published as chapters, he proved for the medical community that asthma was due to spasms of the air passages caused by irritation of nerves. Salter’s asthma theories are frequently cited in medical texts regarding asthma for the next 50 years. Those physicians who accepted Salter’s theories -- and this consisted of most physicians -- referred to Salter’s nervous theory as the “Nervous Theory of Asthma.”

1900. The discovery of epinephrine created a lot of buzz among the medical community, and it was trialed for a variety of diseases, including asthma. This worked to confirm an old theory, that asthma was due to airway spasms, and a new theory, that asthma was due to dilated blood vessels resulting in pulmonary congestion. These theories spawned from the fact that epinephrine both dilates airways and constricts blood vessels. So, for the first time in many years, the nervous theory becomes less significant among asthma physicians.

1910. This was the year that allergies were linked with asthma. This revelation would have no immediate impact on our history, but it will within the next 20 years.

1920’s. German physicians became infatuated with psychosomatic medicine, and out of this infatuation grew an increasing interest in the idea that asthma was a psychosomatic disorder. Among these physicians was Dr. Franz Alexander, who will make a significant contribution to our history about 30 years later. .

1930’s and 1940’s.Most physicians continued to believe that asthma was triggered by emotions. However, their main emphasis now was attempting to control allergies.Also, as researchers started learning more about allergies, they realized that asthma symptoms were the result of an abnormal immune response to allergens. So, the nervous theory of asthma takes a back seat to this new thinking about asthma.

1951.  By now, Dr. Franz Alexander had migrated to the United States, and here he wrote a paper listing asthma as one of the seven psychosomatic disorders. This, in turn, re-established credibility of the nervous theory of asthma for physicians in the developed world.

1980’s.Nervous disorders, such as anxiety, were thought to have an impact on asthma, but no longer to cause asthma. Poorly controlled anxiety might cause an asthmatic to not stick to a prescribed asthma treatment regimen, resulting in poorly controlled asthma. Treatment for poorly controlled asthma, therefore, might involve counseling to control anxiety.

1990’s. You might hear things like: “While stress and anxiety are no longer thought to cause asthma, both may act as asthma triggers.” This may have acted as a relief, of sorts, for asthmatics, who were tired of hearing about asthma being all in their heads.

Today.Modern evidence has brought upon a resurgence, of sorts, of the nervous theory of asthma. Studies seem to show that asthma might contribute to anxiety and depressive disorders, and that anxiety and depressive disorders might contribute to asthma. This new evidence comes with a modern twist, which includes the idea that not all asthma is nervous in origin. However, knowledge of a possible link should make physicians better armed to both diagnose and treat anxiety and depressive disorders in asthmatics in an effort to help them obtain ideal asthma control.

No comments:

Post a Comment