Asthma: statistics and definitions

Asthma statistics

Typical asthma attack

Asthma is a chronic inflammatory disease of the bronchi which includes several processes:
  • Hyper-reactivity of the bronchi
  • A localised inflammation and thickening of the bronchial wall accompanied by mucus.
  • A narrowing of the bronchi, called broncho-constriction.

During a typical asthma attack the bronchi contract and produces a swelling, which narrows the airway opening. This constriction can prevent effective breathing and oxygen exchange.

This inflammation of the bronchi prevents the passage of air and causes the symptoms of an asthma attack.
The feelings of unease felt during an asthma attack is caused by the restricted air circulation in the respiratory tract.

Bronchial inflammation may still be present even in the absence of symptoms, which is why some asthmatics stop taking their treatment too early.
This chronic inflammation causes a remodelling of the bronchi, which in turn worsens the asthmatic disease if no proper treatment is implemented.
  • During uncontrolled asthma episodes, asthmatics may struggle with breathing in and out.
  • Coughing and a characteristic wheezing usually accompany this breathing difficulty.

Other asthmatic symptoms which are less typical and for some can delay diagnosis

Characteristic asthma attacks are straightforward to diagnose and treat. However, many asthmatics do not present this way and live with underlying symptoms for many years, therefore without diagnosis.
  • Episodes of a dry cough develops over several weeks, months or years, which generally occur in the evenings, during the night and or are caused by effort.
  • Repetitive bronchitis can also be hiding an asthmatic condition
  • Breathlessness may also be a symptom of asthmatic disease.
  • Some adults and children are often very tired which may be symptomatic of this disease.
  • A frequent cough, persisting for several weeks after a cold.

Many people present these symptoms for years, but none of the symptoms are ever linked to asthma. The disease, when left untreated, worsens gradually and can, years later, develop into respiratory failure with consequences which can be both severe and beyond control.

Some asthmatic people never suffer from asthma attacks

  • Asthma is an insidious disease, which can develop slowly without a patient being aware of it.
  • Many people live for years with a shortness of breath, which worsens very gradually without any other symptoms.
  • These people who feel constricted in their daily lives for years do not think for a moment that they are asthmatic.
  • GP's can miss the diagnosis as mild symptoms can be accounted for other problems.

Asthma can be compared to an iceberg of which the visible part corresponds to the typical attack with its wheezing and the hidden part, invisible, with more insidious symptoms, less easy to connect to asthma, like breathlessness or coughing episodes.

Identifying the symptoms of asthma

Identifying the signs of a possible asthmatic condition is probably the most important thing patients should know.
Detecting the symptoms of this disease could help thousands of people who would then consult a doctor who knows the disease well, and can both diagnose it and treat it properly.
Simple questions should be systematically asked to all asthmatics during a consultation.
The answers obtained make it possible to evaluate the patient's unease and to adapt the treatment accordingly.
  • Having a family history or `atopic' background can increase you chance of developing asthma.
  • Unease during certain activities such as sports or running after a bus for example, at home or at work
  • Breathlessness: when climbing stairs, up two or three floors, when walking or at rest
  • Waking in the night - feeling of chest tightness, cough, breathlessness, wheezing, or chest pain
  • Persistent dry cough especially at night time
  • Frequent use of a bronchodilator inhaler
  • Frequent tiredness from little effort
  • Unease over the telephone, a situation which often intrigues interlocutors: "it's funny, you sound out of breath".
  • One or more episodes of bronchitis followed by a cough for several weeks.

To diagnose asthma some simple tests can be performed by your GP. Lung function tests are carried out by the nurse in the asthma clinic and are accurate in making a diagnosis. Do not hesitate to discuss this with your GP if you feel you have asthma symptoms..

A newborn which presents at least three episodes of respiratory wheezing, a shortness of breath, several episodes of wheezing bronchitis or "asthmatic" bronchitis before the age of two must be regarded as an asthmatic child.

Tiredness is sometimes the only symptom of asthma

The only symptom of discomfort that describes certain asthmatic people is a fatigue that worsens during periods of physical exertion, sometimes tiny daily efforts.
  • To walk, climb stairs, shopping sometimes represents an insurmountable effort that patients don't realise is caused by asthma.
  • Some asthmatics can live for decades with a fatigue caused by an obstruction of their bronchi, and usually a severe one.
  • When a doctor carries out this diagnosis, sometimes by chance or in the wake of a secondary infection or aggravation of the disease, these patients are surprised to note the dramatic improvement of their "fitness" and their tiredness after following the suggested treatment.
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