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== Da Costa’s Syndrome ==
== Da Costa’s Syndrome ==
{{disease|G93.3|Da Costa´s syndrome|''...classification''}}
[[nl:Syndroom van Da Costa]]
[[nl:Syndroom van Da Costa]]
'''Da Costa's Syndrome''' is a disorder of unknown origin<ref name="White">{{cite book | last = White | first = Paul Dudley | authorlink = | coauthors = | title = Heart Disease | publisher = MacMillan | date = 1951 | location = New York, New York | pages = 578-591 | url = | doi = | id = | isbn = }}</ref><ref name="pmid3314950">{{cite journal |author=Paul O |title=Da Costa's syndrome or neurocirculatory asthenia |journal=Br Heart J |volume=58 |issue=4 |pages=306–15 |year=1987 |pmid=3314950 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=3314950}}</ref><ref name="nature"> {{cite journal|title=The Nature of Chronic Fatigue Syndrome (CFS)|journal=J.A.M.A.|date=September 1996|first=David H.P.|last=Streeten|coauthors=|volume=280|issue=12|pages=Editorial|id= |url=http://www.mindfully.org/Health/Chronic-Fatigue-Syndrome-CFS.htm|format=|accessdate=2008-10-04 }}</ref> which involves a set of symptoms that include left-sided chest pains, palpitations, breathlessness, faintness, dizziness and fatigue occurring exclusively in response to physical exertion in some patients,<ref name="Lewis">Lewis T. (1919) The soldier’s heart and the effort syndrome, Paul B. Hoeber, New York.</ref> but in most cases the symptoms occur to a lesser degree at other times. The tendency to excessive tiredness during the day, and a reduced capacity for exertion<ref name="Baker">{{cite book | last = Baker | first = Doris M. | authorlink = | coauthors = | title = Cardiac Symptoms In The Neuroses | publisher = H.K.Lewis & Co.,Ltd. | date = 1955 | location = London | pages = 50 | url = http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=2500672&blobtype=pdf | doi = | id = | isbn = }}</ref><ref name="Wooley3"> {{cite journal|title=Early Hospitals Devoted to Heart Disease: Military Heart Hospital at Hampstead, England: World War 1|journal=American Heart Hospital Journal|date=2004|first=Charles F.|last=Wooley M.D.|coauthors=|volume=2|issue=|pages=175-177|id= |url=http://www3.interscience.wiley.com/journal/118818245/abstract?CRETRY=1&SRETRY=0|format=|accessdate=2008-11-08 }}</ref>, are the most prominent complaints.
'''Da Costa's Syndrome''' is a disorder of unknown origin<ref name="White">{{cite book | last = White | first = Paul Dudley | authorlink = | coauthors = | title = Heart Disease | publisher = MacMillan | date = 1951 | location = New York, New York | pages = 578-591 | url = | doi = | id = | isbn = }}</ref><ref name="pmid3314950">{{cite journal |author=Paul O |title=Da Costa's syndrome or neurocirculatory asthenia |journal=Br Heart J |volume=58 |issue=4 |pages=306–15 |year=1987 |pmid=3314950 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=3314950}}</ref><ref name="nature"> {{cite journal|title=The Nature of Chronic Fatigue Syndrome (CFS)|journal=J.A.M.A.|date=September 1996|first=David H.P.|last=Streeten|coauthors=|volume=280|issue=12|pages=Editorial|id= |url=http://www.mindfully.org/Health/Chronic-Fatigue-Syndrome-CFS.htm|format=|accessdate=2008-10-04 }}</ref> which involves a set of symptoms that include left-sided chest pains, palpitations, breathlessness, faintness, dizziness and fatigue occurring exclusively in response to physical exertion in some patients,<ref name="Lewis">Lewis T. (1919) The soldier’s heart and the effort syndrome, Paul B. Hoeber, New York.</ref> but in most cases the symptoms occur to a lesser degree at other times. The tendency to excessive tiredness during the day, and a reduced capacity for exertion<ref name="Baker">{{cite book | last = Baker | first = Doris M. | authorlink = | coauthors = | title = Cardiac Symptoms In The Neuroses | publisher = H.K.Lewis & Co.,Ltd. | date = 1955 | location = London | pages = 50 | url = http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=2500672&blobtype=pdf | doi = | id = | isbn = }}</ref><ref name="Wooley3"> {{cite journal|title=Early Hospitals Devoted to Heart Disease: Military Heart Hospital at Hampstead, England: World War 1|journal=American Heart Hospital Journal|date=2004|first=Charles F.|last=Wooley M.D.|coauthors=|volume=2|issue=|pages=175-177|id= |url=http://www3.interscience.wiley.com/journal/118818245/abstract?CRETRY=1&SRETRY=0|format=|accessdate=2008-11-08 }}</ref>, are the most prominent complaints.

Revision as of 15:10, 19 July 2015

Da Costa’s Syndrome

Disease classification WHO
G93.3 Da Costa´s syndrome
...classification

Da Costa's Syndrome is a disorder of unknown origin[1][2][3] which involves a set of symptoms that include left-sided chest pains, palpitations, breathlessness, faintness, dizziness and fatigue occurring exclusively in response to physical exertion in some patients,[4] but in most cases the symptoms occur to a lesser degree at other times. The tendency to excessive tiredness during the day, and a reduced capacity for exertion[5][6], are the most prominent complaints.

The condition was first identified by J.M.DaCosta who observed it in soldiers during the American Civil War and later studied 300 patients to distinguish it from heart disease which has similar symptoms.[7] Since then there have been many heated disputes and controversies[1][8][2][9][10] about it being heart disease or not[1], real or imaginary[1][11], genuine or malingering[12], and physical or mental[13], and more than 80 different theories and labels have been proposed and scientifically investigated[14][15]. Da Costa called it “irritable heart” but the most appropriate label according to Harvard professor Paul Dudley White, who studied the subject for more than 50 years, was neurocirculatory asthenia.[1] Other authors have regarded Da Costa’s syndrome as the best name because it does not give any attribution to hypothesised cause and is therefore the most objective term.[11]

The typical patient is a sedentary worker with a long, thin, flat, or narrow chest, and a stooped spine, as depicted in a life sized portrait which was previously displayed in the Museum of the Post-Graduate Medical School of London.[16] Notable medical authority Oglesby Paul summarised many of the Da Costa controversies in a 1987 edition of the British Heart Journal[2] and since then the use of the term has become rare and, although the ailment is still a common and easily diagnosed problem, it has been absorbed into other modern categories of labelling. The abnormal response to effort is consistent with the modern equivalent of effort intolerance which is a symptom of a type of postural orthostatic tachycardia syndrome which is a sub-type of the chronic fatigue syndrome[17] [1] [18]. Other popularly used labels included soldier’s heart, effort syndrome, anxiety neurosis,[1][2] and post-viral fatigue syndrome.[15] All modern ideas about cause and labelling have their strong adherents and opponents, however, none have yet been scientifically proven or universally accepted.

History

1864-1899

Da Costa's syndrome is named after the surgeon Jacob Mendes Da Costa, who first observed it in soldiers during the American Civil War. The typical case was the civilian who enlisted in the army and was sent on long hours of marching, often up to twenty miles in one day, sometimes at double quick pace, with poor food and water, and in bad weather. They developed a viral infection and diarhoea and became exhausted and fell out of line and were hospitalised for treatment. After several months they recovered from the infection but when they returned to marching they were unable to keep up the pace as before and were again hospitalised, and although making a partial recovery they continued to suffer from abnormal palpitations, breathlessness and fatigue in response to mild exertion and were unfit for full military duty. Da Costa also noted that the pulse was always greatly and rapidly influenced by position, such as stooping or reclining.[7]

Another physician, Earl de Grey, had previously presented four reports on British soldiers with these symptoms between 1864 and 1868, and attributed them to the heavy weight of military equipment being carried in knapsacks which were tightly strapped to the chest in a manner which constricted the action of the heart. Also in 1864, Henry Harthorme observed soldiers in the American Civil War who had similar symptoms which were attributed to “long-continued overexertion, with deficiency of rest and often nourishment”, and indefinite heart complaints were attributed to lack of sleep and bad food[19]. In 1870 Arthur Bowen Myers of the Coldstream Guards also regarded the accoutrements as the cause of the trouble, which he called neurocirculatory asthenia and cardiovascular neurosis[20][21][22][23].

1900-1919

In 1916 Sir James MacKenzie chaired a major medical conference aimed at gaining a better understanding of the condition[12]. He attributed the fatigue to the abnormal pooling of blood in the abdominal and peripheral veins during exertion, which reduced blood flow to the brain. He also observed that the soldiers were fit and well at the start of the war, but after becoming severely exhausted by long marching or viral infections they recovered partially but with a reduced capacity for effort. They experienced abnormal palpitations and breathlessness which impaired their capacity to run fast, or to run up and down stairs, or to keep up with their comrades in marches as before.[23]

Between 1916 and 1919 several synonyms were used to describe Da Costa's syndrome in World War 1, including soldier's heart and neurocirculatory asthenia. Sir Thomas Lewis gave it the title of the effort syndrome because he observed that in some cases the symptoms occurred exclusively in response to physical exertion. Many of these patients had poor physiques with narrow or flat chests and a history of minor symptoms of the condition prior to enlisting in the army, and they often came from sedentary occupations which they chose because of difficulties in doing strenuous work. They had also avoided vigorous sports for similar reasons[4]. Some of them enlisted several times and were repeatedly rejected but persisted until they were finally accepted, and then their symptoms were aggravated or caused by strenuous exertion at training camps, or while on long marches where they contracted viral infections, and after recovering from the fever they found that they could not sustain their former levels of activity. Graded exercise testing was used to gauge the severity of their condition, and both Lewis and Osler used it as a treatment[24][4][25] which enabled some of the soldiers to return to full military duty, but others were put on light duties or discharged. After the war they generally changed to lighter occupations than they had before the war, and some were chronically incapacitated by their fatigue[4].

1920-1949

In 1939 J.L. Caughey Jnr. reviewed the literature of internal medicine on the subject of cardiovascular neurosis which referred to cases that involved symptoms similar to those of heart disease occurring where there was no apparent disease of the heart or blood vessels. The typical patient had his tonsils and appendix removed as a child, as well as many infectious illnesses and colds. He had a thin physique, and a weak stomach, and his kidneys had been damaged by Scarlet fever, and there were frequent fluctuations in the color and volume of his urine. His blood pressure was unstable, and his peripheral circulation was poor, with pale fingers and toes in cold weather. He had difficulty with concentrating and thinking clearly and had a poor memory. They had a respiratory infection three years prior to suffering from pain in his heart, shortness of breath, dizziness, faintness and weakness. All of his symptoms were “made worse by exertion or nervous strain”. They often felt breathless and would complain of not being able to expand their chest far enough to get a full breath. Caughey also noted previous exercise tests which indicated "a physiological abnormality in the patient as compared to the normal person”, but he believed that it was due to their fear that exercise would cause a heart attack. In describing the lack of stamina he suggested that there were two groups of patients, the first who never developed the ability to persevere against the challenges and adversities of life, and those who tried but gave up.[26]

In the 1940’s there were several studies aimed at determining the physical basis of these conditions[11][27] and in 1947 S.Wolf studied the "respiratory distress characterized by inability to get a full breath” and found that the thoracic diaphragm function was abnormal, and when the diaphragms contractile state during inspiration was such that adequate inspiration was no longer possible, breathlessness occurred with a feeling of inability to take a full breath. The spasm of the diaphragm was often accompanied by pains in the chest and shoulder, occlusion of the lower end of the esophagus, and difficulty swallowing.[28] Also in 1947 a report by Cohen and White noted that the complete mechanism of Da Costa syndrome symptoms was unknown but when respiration was investigated objective abnormalities were found, "just as when other symptoms of N.C.A. are investigated with objective methods, which demonstrates that the abnormalities are not all in the subjective sphere". The respiratory abnormalities at rest were few but during exercise the abnormalities became more pronounced and the deviations from the normal became greater as the rate and amount of exercise increased.[29]

1950-1979

In 1950 Edmund Wheeler presented the results of a 20-year longitudinal study of 173 patients with "effort syndrome" and found that the condition involved varying degrees of disability but all patients tended to improve with a low-stress lifestyle. He concluded that, although they all had what was called ‘anxiety’, they did not develop a higher frequency of illnesses such as peptic ulcers, diabetes, or asthma etc, “which have recently been said to be caused by anxiety” and that “there is no evidence that anxiety causes these diseases”.[13]


In 1951 the fourth edition of Paul Dudley White’s book “Heart Disease” contained a chapter on “Neurocirculatory Asthenia”, because, as he explains, the symptoms are similar to heart disease, but are not the same, and he adds, that they are also similar to, but can occur in the absence of anxiety, and are not exactly like those produced by effort in a normal healthy person, and therefore need to be discussed separately.

He describes the typical group of symptoms which are precipitated by excitement or effort, and stated that “it constitutes a kind of fatigue syndrome” and in some cases “it is more or less a chronic condition,” and that regardless of it’s pathogenesis it was a real illness. In some patients the neurocirculatory symptoms were most prominent, but for some unknown reason there were other cases where the main symptoms were gastrointestinal or cerebral. The general causes of the condition appear to include such strains as worry over business, social, or family matters, emotional conflicts, physical or nervous fatigue, and exhaustion from acute infections or illnesses. The organic basis was not known although the possibilities which had been considered in the previous 25 years, included thyrotoxicosis, low-grade infection, adrenal hyperactivity, hyperventilation resulting in alkalosis, and lack of salt, but none have been confirmed. Many of the patients had thin physiques with an “unusually vertical position of the heart”, and “abnormality of shape of the capillary loops at the base of the nail”...“It is common to find that close relatives have had similar problems, and recent studies indicated that it was one of the Mendelian dominant group of inherited disorders.” It was common in World War 1, occurred in civilians as well as soldiers, and it is generally seen in young adults, but can occur at any age, and is more common in women than men. The frequent sighing distinguishes the condition from heart disease, and the fatigue sometimes produces more incapacity, and even complete disability. It is a real and not an imaginary incapacity, even though at first glance it may have appeared imaginary in World War 1 (1914-1918) when it was sometimes labelled "malingering", and even though in civilian practice it has frequently been diagnosed as "mere nervousness". It is milder in civilian life than in war and it is so commonly associated with psycho-neurosis of the anxiety type “that the two conditions have sometimes been confused one for the other or considered to be synonymous, the term anxiety neurosis having come to mean for many the same collection of symptoms which identify neurocirculatory asthenia.”

Treatment involves rest for days or months or as long as required, and elaborate psychotherapy is generally not needed. "The condition must be discussed seriously, not lightly as if it was of no importance”, and it is equally wrong to dismiss it as negligible or imaginary, as it is to to regard it as dangerous or serious and a threat to life which demands bed rest. Management of the symptoms involves normal but quiet work and play and the avoidance of long working hours or burdensome tasks. Like most people these patients usually try to keep up with their friends in strenuous living in the business, professional, or social world but with clear medical advice they soon learn the benefits limiting their activities and gradually adjust them to suit their symptoms, and are surprised at recapturing a feeling of well being."[1]

In 1956 Paul Wood’s 2nd edition of Diseases of the Heart and Circulation included a chapter on the effort syndrome. He described how it “is characterised by a group of symptoms which unduly limit the subject's capacity for effort" and recorded that "The cardinal symptoms" of irritable heart, soldier’s heart, disordered action of the heart (D.A.H.), etc. are "breathlessness (93%), palpitations (89%), fatigue (88%), left inframammary pain (78%), and dizziness (78%), or syncope (fainting) (35%)". He also suggested a variety of methods for diagnosing the difference between the symptoms and those of heart disease. For example the chest pain usually involved a sharp stabbing sensation in the lower ribs caused by prolonged poor posture. He noted that the location of the pain was so near the heart that “it seems to convince the patient that his heart is diseased”, especailly because of the palpitations that occur at other times. It was natural to draw that conclusion but some patients developed a morbid fear of heart disease and death, however, although the exact mechanism was not known, it could be “immediately abolished by the intramuscular injection of 2 ml. of novocaine at the site of maximum intensity and tenderness”, indicating that it was in the muscle between the ribs and was related to fibrositis. The breathlessness involved frequent deep sighs brought on by exercise, but were also common at other times, and the patients will say they are not able to obtain a full and satisfying breath. This can also occur at night when it "may be confused with asthma. "A simple test" for the symptom involves forced hyperventilation where "The patient is asked to breath deeply and rapidly for one minute." When a healthy person is asked to stop he feels breathless for about 20 seconds, but a patient with Da Costa's syndrome "continues forced breathing, explaining later that he felt breathless." i.e. there is an abnormal breathing pattern - "Dyspnoea" instead of insufficient breathing - "apnoea". Also "Normal subjects have no difficulty holding the breath for at least 30 seconds, but patients with Da Costa's syndrome usually give up very quickly. With regard to the fatigue the patients often do not feel refreshed when they wake up in the morning, and they may "feel tired and listless during the day. The other type of fatigue which is related to effort involves a delay in the return of pulse rate after exertion.[16]. In considering the influence of psychological factors he noted that the similarity of the symptoms to heart disorders may be the cause of a fear of heart disease (cardiophobia), which contributes to the reluctance to exercise (i.e. resulting in exercise phobia), and that all of the symptoms may have originated from a general anxiety neurosis resulting from genetic or familial factors, or poor health during childhood, and the consequent lack of exercise and the avoidance of sport during childhood.

In 1976 Charles Wooley presented an article about the history of Da Costa’s syndrome in the journal called ‘Circulation’. He reported that Da Costa originally called it ‘irritable heart’ when he noticed the condition amongst soldiers during the American Civil War. However he added that a later study by Thomas Lewis revealed that most of the soldiers who had the problem came from sedentary occupations and “a large percentage” were “affected by the condition in civil life many years before joining the Army” and that it was not particularly a soldiers malady, and that it also affected some athletes. A further study in 1941 by Paul Wood reported that it was commoner in women[11].

The author also noted that possibly several distinct, but similar conditions were causing confusion in diagnosis, and concluded that many of Da Costa’s original patients had been described as having occasional cardiac sounds and murmurs that could now be included in the newly evolving category of mitral valve prolapse syndrome. He then recommended deferred judgement about the nature of the other cases, where advances in technology were likely to provide a more precise understanding of the relationship between the various causes [30].

1980-1999

In 1980 Soviet researcher V.S.Volkov studied the physical fitness levels of patients with angina heart disease, and compared them to those with neurocirculatory dystony (Da Costa’s syndrome). He divided heart disease patients into three groups with heart pain at rest, heart pain every day, and heart pain occasionally. He also divided NCD patients into three stages of mild, moderate, and severe. 80% of Da Costa’s syndrome patients were fitter than heart disease patients, but 20% were not, and had to stop the exercise because of changes in their heart rate, or overwhelming and radiating chest pain, general fatigue, and fear for their hearts.[31]

In 1987 prominent Harvard researcher Oglesby Paul presented a ten page history of Da Costa’s syndrome in the British Heart Journal, in which he outlined all of the controversies of the previous hundred years. He reported that many theories and labels had been proposed, but for each one which had supporting evidence, there were other studies which contradicted the findings. For example, if one study presents anxiety as a cause, another study will find patients who are not anxious, another study will report hyperventilation as a cause, yet there will also be studies which show patients who don’t hyperventilate, and for each study that shows a relationship to mitral valve prolapse syndrome there will be others that show no evidence of MVP. He concluded that the condition still existed, and was easy to diagnose, effecting 4% of the population, but that there were newer more popular labels, such as ‘anxiety state’, where he added that such labels would do no harm as long as the important history of the subject was not forgotten.[2]

In 1998 David Streeten presented an article in JAMA[3], explaining that the fatigue reported by Da Costa and Lewis were early descriptions of a “newly recognised” delayed form of orthostatic hypotension which is a feature of some types of Chronic Fatigue Syndrome. He stated that “as a working hypothesis”, the fatigue was due to abnormal pooling of blood in the lower limbs which delayed and reduced the flow of blood and oxygen supply to the brain. That effect was compounded by a reduced circulating red blood cell mass. He then emphasised that it is essential to identify these physical abnormalities by repeatedly measuring the patients blood pressure in recumbency and after standing for ten minutes or tilt testing, and that “it is inappropriate to consider that CFS is a manifestation of mental disorder” unless those physical causes are excluded. He added that the expense of these tests was not unreasonable considering that almost every type of work or lifestyle required a person to stand for six hours per day without experiencing the symptoms associated with reduced blood pressure. He then concluded that the instigating cause remains unknown, and that effective and safe treatments for the debilitating symptoms are still not available and that further research is required.[3]

The relevance to modern labelling terminology between 2000-2008

The use of the term Da Costa's syndrome has fallen out of fashion and is rarely used nowadays,[2] however to put it into context with modern labels there are some relevant descriptions from the history of research. In that regard, in 1916 Thomas Lewis noted that in some cases the condition was exclusively related to exertion,[5][4] and in 1956 Paul Wood O.B.E. described it as a syndrome of six clearly identifiable symptoms (which had previously been called "primary"[12] "typical" [32] “characteristic”[33] or "classic"[1] and which he called "cardinal" symptoms[16], and Harvard professor Paul Dudley White described it as a definite malady which was a type of fatigue syndrome that is more or less chronic.[1] Nowadays those typical, distinct, or characteristic features can be seen in conditions which include the symptom with the misnomer of effort intolerance (which should be effort limitations) due to exercise induced postural hypotension.[23][16][34] For example, it is seen in one type of the Postural Orthostatic Tachycardia Syndrome, which is in turn one of the many types of chronic fatigue syndrome[17] [3][34][35][10] [36][18]. However, there are still many different ideas about cause, and the condition has been virtually lost in a sea of other labels[5][2][37] and although there is a vast amount of direct and indirect research evidence for physical cause[28][29][32], none have been universally accepted[14]. The topic remains the subject of ongoing controversy amongst imprecisely defined anxiety disorders, poorly characterised post-war syndromes[38][39][40], and the complex CFS group of ailments[38][41][42][43][35][34], Opinions differ from one medical specialist to another[17][10][18], from one medical authority to another, and from one medical consumer group to another, and change regularly[41][15][18]. Dictionary definitions and label priorities also alter with the changes in opinion, however the Merriam Webster online Medical Dictionary [2] includes a definition of neurocirculatory asthenia, with the typical symptoms occurring in relation to exertion and in the absence of heart disease, and provides the synonyms of "cardiac neurosis, effort syndrome, irritable heart, and soldier's heart" [44], which were the most frequently used synonyms for Da Costa’s syndrome.[1][2] Indeed Dorland's medical dictionary lists Da Costa's syndrome and neurocirculatory asthenia as direct synonyms[45] and the current 2008 edtion of Harrison’s Principles of Internal Medicine describes the symptoms of the modern term chronic fatigue syndrome as being “not new” with the comment that in the past it may have been diagnosed as the “effort syndrome”[17] defined in 1919 by Lewis[24][4].

Symptoms

The typical symptoms of Da Costa’s syndrome are palpitations, breathlessness, chest pains, and or fatigue[16][32][46][12] occurring exclusively in response to physical exertion in some cases[4][16][6], and occasionally to changes in posture[47][12], but in many patients they are also associated with some viral infections or nervous strains.[1][26]

  • The palpitations occur as a more forceful and rapid beating of the heart than usual and are generally associated with stress or exertion.[1]
  • The breathlessness is related to spasm and inefficient function of the thoracic diaphragm[28][11][27][29] which is the primary breathing muscle, and it features occasional slow, forced, deep breaths - abnormal sighs or yawns[26][47][14][29][1][5][11][32].The person often feels as if they cannot get a full breath, and they tend to avoid crowded buses, trains and theatres, and they prefer to sit near open windows to get fresh air, or in aisle seats so that they can leave the room quickly if necessary, and in some cases they avoid open spaces where there are crowds. This was due to an abnormal build up of CO2 exhaled by the crowd in a confined space, which tended to increase the frequency of sighs and ultimately cause all of the physical symptoms of the condition, and sometimes a sense of suffocation and a sense of fear that resembled anxiety attacks[14].
  • The most common chest pain is a dull ache or tenderness in the lower left side of the chest with occasional brief, sharp and stabbing sensations in that area[4][1][5][14][11][16][2][32], and there may sometimes be cramping paiins in the muscles on the far left or right side of the chest brought on by muscualr efforts [11][16][1]such as the strain of “lifting a heavy weight”, especially at awkward angles - “in such actions as cranking an engine” [11][16].
  • The fatigue involves an abnormal pattern of tiredness during the day[33] and an excessive response to physical exertion, and is unlike normal fatigue insofar as it tends to persist despite rest[5]. It is related to abnormal pooling of blood in the abdominal and peripheral veins which reduces blood flow to the heart and brain[4][35] , especially during exertion, which explains why faintness and dizziness are often additional features, and why most patients have a reduced capacity for exertion.[23][16][3][17]

Predisposing factors

The condition may be genetic or familial[11][33][29][16][13][26][32][2] and is more likely to affect individuals who had multiple infectious illnesses and surgical procedures during childhood[4][26], and who had thin[23][48][1][49] and stooped physiques[50][11] [30][1][32], and sedentary workers[4] who avoided or never played sport[4][26][1][16][30], and it is more common in women[14][13][11][1][32][2][36][18], and often occurs or starts during a pregnancy[13][14][51]. Most soldiers who developed the condition were former sedentary workers who had minor indications of the typical symptoms prior to the war.[7][4][14][30]

Onset of symptoms

In some cases the condition appears to have been present since birth, or ever since the patient can remember[26][48] Jones, Maxwell; R.Scarisbrick (1946). "The effect of Exercise on Soldiers with Neuro-circulatory asthenia". Psychosomatic Medicine (8): 188-192. http://www.psychosomaticmedicine.org/cgi/reprint/8/3/188.pdf. Retrieved 2008-12-02. </ref>[29][13][33], but it is often gradual in onset without the patient noticing it or being able to identify an obvious cause[14], or it may start and recur or persist after a viral infection[7][23][4][14][16][2], or after an excessive or prolonged period of physical[7][4][14][38] or emotional stress[19][13][1]. The average age of onset is 25 years[33][14][32].

Causes

According to J.M.Da Costa in his original paper of 1871 the causes were "Fevers" 17%, "Diarrhoea" 30.5%, "Hard field service, particularly excessive marching" 34.5%, and finally, "Wounds, injuries, rheumatism, scurvy, ordinary duties of soldier life, and doubtful causes" 18%.[7][12]

Since Da Costa’s initial report several authors have proposed that anxiety[1][2][45] related to personal or business stress[13][16][1], pregnancy[13][14] and malnutrition[19][1][14][38] can be added to the list of causes.

General Physical Characteristics

Da Costa’s syndrome can affect individuals of any type of physique, but they are generally thin[23][33][48][1][49], with various chest wall deformities and stooped or scoliotic spines[4][30][11][16][32]. They are generally, but have not always been poor athletes and swimmers[29][14], and have an abnormally functioning thoracic diaphragm which results in inefficient breathing and the tendency to sigh more often than usual. They also have a reduced capacity to hold their breath[4], and an intolerance to carbon dioxide which brings on their symptoms[14][2], as does wearing a gas mask[30][11][29] and the infusion of sodium lactate[32]. Other common distinguishing features are abnormalities in the shape of their fingernail capillaries,[1][11][32] and dermatographia where running a finger nail lightly down the chest will leave a trailing red mark and hence the ability to write on the skin.

Physiological Abnormalities related to exertion

Da Costa’s patients have a poor aerobic capacity or low level of fitness which is not related to the lack of exercise[4], and they have breathing patterns and other symptoms which are not the normal response to effort[47][14][29][1][5][11][2]. They have poor diaphragm movement and reduced chest expansion at rest[26][11], and during exercise training such as walking, jogging, or running "they have an easily induced oxygen debt"[1], their breathing become disproportionately shallow, oxygen consumption is lower, and blood lactate levels are higher than normal[14][29][32], in some cases more than double[14], and as the intensity and duration of the exercise increases the physiological abnormalities increase[14][29] which is consistent with the histories and claimed disabilities of these patients[14]. There is also an abnormal pooling of blood in the abdominal and peripheral veins[23][3][35] , and a slow return of pulse rate to normal after exertion[16].

Treatment

The reports of Da Costa, White, Wheeler, and Wood show that patients recovered from the more severe symptoms when removed from strenuous activity, the stressful emotional situations, or the sustained lifestyle that caused them[19][13][1]. In many cases relapses were prevented by determining the limits of exertion and lifestyle and keeping within them[13][1][52][41]. The physical limitations were associated with the abnormalities in respiration and circulation. Other treatments evident from the previous studies were improving nutrition[19], physique and posture,[7] appropriate levels of exercise where possible[23][25][1][2][53], using individually designed graded exercise regimes[24][47][54][38][9][6][32][46] which have been proven to be effective in relieving symptoms and improving exercise tolerance in come cases[12][17]. Some symptoms such as faintness can be prevented or relieved by wearing loose clothing about the neck, chest, and waist[7][20][12], and standing up slowly can prevent the faintness associated with postural or orthostatic hypotension in some cases[16][17], and avoiding postural changes such as stooping, or lying on the left or right side[7][11][12], or the back relieved some of the palpitations and chest pains in some cases. Some of the symptoms can be relieved by laying in a recliiner chair[54], and the chest pain can be temporarily relieved by intramuscular injection of novocaine at the site of tenderness[16]. Also, drinking more fluids, increasing salt intake, and sleeping with the head elevated can reduce the fatigue[55][56][35].

Prevention

In his original paper J.M. Da Costa suggested that the condition tended to become chronic after a prolonged and exhausting viral infection where the person was sent back to full and demanding activity too soon. He therefore recommended that the person should be provided with sufficient rest, nourishment, and gradual physical training to achieve full strength before resuming former duties[7][2]. Various other authors have suggested that the adoption of a moderate lifestyle and avoidance of the extremes can prevent this type of condition from developing[13][1][52], and that this general principle applies regardless of other causes and pathogenesis[57].

Alternative names for Da Costa’s syndrome

The name of Da Costa’s syndrome has changed so often from one specialist[5][14][32], or from one country[31][41][18], or one year to another[14][41][18] that it has created confusion in the study and diagnosis of the condition,[30] as is evident from many research articles which mention four or five in their introduction,[26][47][29][14][1][16][32][30][58][56][6][12][38][42][18] [17] and from a recent website which lists what it claims are more than eighty synonyms.[15] However the title of Da Costa’s syndrome has been regarded as the preferred label by several authors because of its non-attribution and unchallengable aspect.[11] By contrast, the labels such as irritable heart or cardiac asthenia are inappropriate because the ailment is not a form of heart disease[1]. Similarly Soldier’s heart is too specific[2] and so it can be challenged because the vast majority of patients have never been soldiers,[1] and it is inappropriate when the symptoms occur in pregnant civilian women.[59][11] Relating it to Post-viral fatigue syndrome[17] can be disputed because, in many cases the patient could not recall having a viral infection, and the label of Post-traumatic stress disorder (PTSD) can be challenged because many patients have not experienced preceding trauma,[13][2]and the symptoms are not the same as those caused by stress[14] and can have a genetic[33][29] [32][30][2][42], or gradual onset unrelated to stress [29]. Somatoform disorder refers to symptoms occurring in the absence of physical or physiological evidence to account for them [[3]], yet Da Costa’s symptoms have been associated with multiple physical, physiological and biochemical abnormalities[47][48][29][31][2][12][42][18], and the term dysautonomia implies a fault in the autonomic nervous system which, whilst it may be an effect, and has not been proven as a cause[1][11][16][2][36]. There are also discrepancies associated with the label of Hyperventilation syndrome[1][16][2][60], and some patients with MVP have none of the symptoms of Da Costa's syndrome[2][52]. The term anxiety state implies that the patient is in a constant state of anxiety, yet many patients appear calm and are rarely affected by anxiety[29][52][35], and the term anxiety disorder can be disputed because the symptoms are not the same as those produced by anxiety[14][1]and they don’t develop any abnormal incidence of other diseases such as peptic ulcers or asthma which have been previously, and erroneously attributed to anxiety[13][2]and labelled as psychosomatic[32]. Similarly the condition cannot be regarded as an exercise phobia because many patients were capable of strenuous marching prior to developing the condition[7] or were formerly good athletes[48]. However, by referring to the ailment as Da Costa’s syndrome it can be said that it may be related to anxiety, excessive physical or emotional stress, post-viral causes, and unknown causes etc. The symptoms can include orthostatic hypotension and postural tachycardia[35][18] but those terms are not appropriate as labels because they don’t account for the other symptoms. Da Costa’s could be referred to as a type of Chronic fatigue syndrome,[1][57][3][41][42][36][10][18][17] because chronic fatigue is the main symptom, but the other five typical symptoms distinguish it from the general term [4], and from other types of CFS[41].

Differential Diagnosis

The condition needs to be distinguished from angina heart disease (angina pectoris), mitral valve prolapse syndrome[9], hyperventilation syndrome, hyperkinetic heart, cardiophobia[2], normal tiredness[5][33] the normal symptoms of exertion[5][29][1], exercise phobia, panic attacks, anxiety state, and depression, and other similar syndromes such as the the post-traumatic stress disorders and the numerous post-war syndromes.[2]. It also needs to be distinguished from other types of orthostatic hypotension [35][36][18] or chronic fatigue syndromes[10] , which involve separate or different, or additional symptoms. However many patients with Da Costa’s syndrome also have such problems as a coincidence or as a result of the ailment. For example patients who have symptoms similar to heart disease, often develop a fear of heart disease (cardiophobia)[16][2] Also note that Da Costa’s syndrome involves a set of six classic symptoms, and needs to be distinguished from conditions that involve only one or two symptoms[32]. For example hyperkinetic heart may occur on its own as a single symptom, or it may be part of the set of six in a Da Costa’s patient[58][2]. Similarly a person who only has a dual combination of the left-sided chest pain and palpitations does not necessarily have Da Costa's syndrome. Also, characteristically Da Costa’s syndrome involves fatigue which includes both an impaired capacity for exertion[24][25][17], and secondly, an abnormal pattern of tiredness[5]. Therefore, if patients do not have difficulty with exertion they do not have Da Costa’s syndrome,[7] e.g. a person who complains of abnormal tiredness but participates in vigorous sport does not have Da Costa’s syndrome.

Related Conditions

Chronic Fatigue Syndrome
Postural Orthostatic Tachycardia Syndrome [34]
Soldier’s Heart
Chest Wall Syndrome
Costochondritis - left-sided chest pain
Sigh Syndrome
Exercise Intolerance
Mitral Valve Prolapse Syndrome

Portrait of a typical Da Costa’s syndrome patient

[16] Also [5]

References

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