Asthma

Introduction

Asthma is described commonly as the chronic inflammatory (long standing) disease of your respiratory passages. This inflammation results in the spasm of bronchial passage (respiratory air ways) and the production of excessive mucous from their cells along with swelling. The whole cycle of events may cause a feeling of tightness in your chest with breathing difficulty, repeated cough and a wheezing sound (whistling sound) on auscultation of chest.

The severity of an asthmatic episode can range from a feeling of mild breathing difficulty to an uncontrolled asthmatic attack (status asthmaticus) in which case treatment modalities fail to give response and asthma may become fatal. Although, so far your asthma hasn’t gotten a complete cure but with a wide range of drugs and treatment options available, your symptoms can be controlled well and return to their normal breathing pattern. In maintaining your asthma to good control, it is important to be compliant with your doctor in consultation and managing dosage of medications.

Causes and risk factors

The predilection for having asthma is still to be specifically known. But two major factors, which hold the key as to the provoking or stimulating an attack of asthma, are environmental pollutants and genetic predisposition. When dealing with asthma there will always be either of these or both etiologies playing role as triggers. Although it can effect individuals of either sex or age, asthma is encountered more commonly in children under the age of 18 years. There is no general rule as to what might provoke asthma in you and not in others.

Asthma triggers :

·         Environmental allergens like pollens, house dust mites, cockroaches, pet animals like cat and dogs’ dander, rodents and mould can provoke asthma.

·      Infection: Viral or bacterial upper respiratory tract infection quite often trigger an asthmatic attack. A mild cold is what it appears in beginning progressing to full blown asthma with wheezy chest. Industrial and chemical fumes are easily blamed for asthmatic symptoms termed as occupational asthma.

·      Exercise induced asthma:  Physical exercise specially in cold weather conditions easily provoke mild to severe attack. The triggering factor is dry inhaled air stimulating allergic reaction and bronchospasm.

·       Food consumed: In certain individual specific food can trigger asthma. The likes of shellfish, peanuts are leading food items notified. In some even eating eggs, fish and wheat can elicit asthmatic attack.

Food preservatives can trigger asthma, such as sodium bisulfite, potassium bisulfite and sodium sulfite found in dried fruits or vegetables, pickled food, wine and beer.

·     Drug induced asthma:  Commonly used anti-inflammatory analgesics drugs like aspirin, ibuprofen, and beta blockers result is asthma  in person having history of allergies.

·       Stress and emotion  :   Getting angry at social or work issues, receiving a good or tragic news, can all lead to provoking an asthmatic attack. In women during menstrual phase symptoms of wheezing and cough may progress into full blown asthmatic situation.

·    Gastro-esophageal reflex disease(GERD): With symptoms this can damage respiratory passages and incite asthma.

Risk Factors

 ·       Genetic predisposition, means if a child has either or both parents or any of brothers or sister suffering from asthma ,the chance of  asthma effecting that child will increase.

·        Atopic individual, are those who have greater tendency of having different sorts of allergic condition like hay fever or atopic dermatitis or allergic rhinitis. These individuals are more susceptible to develop asthma at any stage during life.

·     Smokers and those exposed to passive smoking or occupational fumes can easily get triggers for their asthma. The most damaging aspect of this risk factor is irritant to moist respiratory mucosa along with damage to cilia of airways.  Excessive mucous production in one hand and failure to sweep that outside the passages adds to aggravate asthma.

·      Women smoking during pregnancy will deliver premature low birth baby. This in turn puts the child into more risk. A study carried out at division of pediatric pulmonology  (Orlando florida pediatric clinics) have concluded a strong association between low birth weight and asthma risk.

·    Obesity & asthma association is well documented. Asthmatic overweight show improvement in their symptoms when they loose weight. It may have genetic , gastro-esophageal reflex, low physical activity and diet as co-factors.

3.0   complications

Poor asthma control gradually results in permanent lung damage and following complication :

·    Disturbed routine: A persistent cough and wheeze makes life miserable and uncomfortable to the extent, that sleep and day time activity is disturbed. Be it work or recreational, carelessly handled asthmatic becomes breathless with slightest of physical exertion as lung function have been compromised with lack of treatment compliance.

·      Work and study absence : Failure to follow treatment plan results in persistent symptoms and frequent flare ups. Inability to focus at work and study interferes in continuity and absence.

·      Altered airways anatomy/airway remodeling  :     Poor control results in permanent narrowing of respiratory bronchi. Continues inflammation and lack of mucous drainage is the main cause of such change. Narrowed airways result in more frequent attacks , further aggravate the situation.

·       drugs side effects  : whether inhaled or oral steroids their long term use can have deleterious effect on general health.

·        Status asthmaticus  : Most severe form of asthma ,which if not controlled well in time proves fatal. The airways are so much narrowed that breathing in and out becomes minimal. With so much awareness and advancement in treatment option this complication has become rare.

4.0 Pharmaceutical therapies

Like all the other chronic(long standing) illnesses, the pillars on which good asthma control stands are preventive measures and compliant to drugs prescribed. Knowing your asthma triggers , keeping them at bay, watching out your airway status through home peak flow meters are measure playing major role in better control.

Prescribed medication for asthma  :    The main criteria for medical treatment you will be  given are following :

Your age.

Severity of  your symptoms.

Your asthma triggers.

What agent suits you best.

Long term preventive medication are best suited as they keep inflammation in control. And there are drugs available for any acute severe attack.

Medicine for long term management : As we have come to know ,preventing asthma attack will gradually increase lungs capacity and bring improvement in their function, these long term medicine usage is the mainstay of your asthma control. They are to be consumed on daily basis which keeps a check on acute episodes.

·        Inhaled steroids : Before the advent of inhalation steroids ,oral steroids were giving serious systemic side effects. That has been minimized when steroidal anti-inflammatory agents just act locally without significantly getting absorbed to produce much ill effects. They are to be taken daily. Included are: Fluticasone,Budesonide, Ciclesonide,Flunisolide

Beclomethasone and Mometasone.

Generally safe for long term use, some minor side effects have been observed with inhaled steroids. Risk of oral thrush, a fungal infection of mouth,  hoarseness of voice due to effect on vocal cords. In children growth retardation has been noticed but that is well compensated during growth catch up phase. Osteoporosis , a bone demineralization , a side when high doses of inhalations are taken. Cataract and glaucoma are other side effects notified in elderly asthmatic.

·        Leukotriene Modifiers. Included in this class are : Montelukast, Zafirlukast, Zileuton .

Zafirlukast reduces hyper-responsiveness of airways to histamine, Zileuton has its effect in allergic-induced airways response. These agents have long duration of action lasting 24hours. The side effects are, aggression, hallucination, agitation, and suicidal tendencies. Any untoward side effects must be reported to your doctor.

·        Long-acting beta agonist.  They are commonly known as brochodilators. They dilate or open the narrowed airways . They too are to be taken as inhalation. Included in this class : Salmeterol Formotrol, Bambuterol.. There is warning in their usage as they may aggravate an asthmatic attack, hence they are to be taken in combination with inhaled steroid. The duration of their action on respiratory passages last for almost 12 hours. Although they ease breathing effort but when you will be exposed to irritants they fail to control they excessive mucous production and swelling within respiratory airways. Deaths have been reported in LABA’s use as single drug therapy.

·       Combination Inhalers : They are combination of inhalation long-acting beta agonist and steroids. Included are Fluticasone-Salmetrol, Budesonide-Formoterol, and Mometasone-Formoterol combination. They exhibit side effects similar to when used as single agent but higher doses of steroid can avoid more serious side effect of fatality. Only used in case when steroid alone are giving good control of your asthma.

·        Theophyline  : It is bronchodilator, which opens the airways and relaxes labored breathing efforts . But in recent years its used is not so common.  Side effects include irritability, headache , nausea, sleep disturbances, diarrhea, restlessness and increased frequency of urination.

Life saving fast acting drugs : 

They may be needed for short term and rapid relief of symptoms, before indulging in sports activity or work of physical nature and during an acute asthmatic attack, hence termed “rescue medicine” . Following are some effective medicine for purpose mentioned :

·          Short acting beta agonists :  The big advantage they will give you is to act fast and control the troubling symptoms immediately. Best taken just before exercise ,taking showers or going out in cold weather. Albuterol , Levalbuterol, Pirbuterol are used presently with good results. Commonly taken via portable nebulizer as mist vapors, or hand managed inhaler. Side effects include skeletal muscle tremors, tachycardia, nervous and shakiness and sleep disturbances.

·        Ipratropium, is anti-cholinergic agent, which has property of relaxing brochial smooth muscles and easing breathing. But it is not preferred over other quick or rescue medicine before exercise or during an acute asthmatic attack. Side effects are dry mouth and increase in wheezing. Ideally this drug is given with short acting beta agonist.

·       Oral and inject able corticosteroids :  They are used on short term basis due to their strong anti-inflammatory ,anti-allergic effect in asthmatic. But side effects limit their use on long term basis. The commonly use steroids are prednisone and methyl prednisone and inject able triamcinolone. Side effects they exhibit are, increase appetite, weight gain, increase blood sugar in diabetics ,mood changes, rise in blood pressure in hypertensive, worsening of CCF(congestive cardiac failure), osteoporosis and sympathy.

Quick relieving medicine are not to be used when you have satisfactory control with your long term daily medication.

Allergic medication

·        Allergy shots : Also termed immunotherapy, are preparation of substances with whom you are allergic. They are injected in small doses after careful skin testing. Weekly shots are given with gradual increasing dose for 4-6 months. The idea behind such therapy is to make your body less responsive to some particular allergens.

·       Omalizumab(Xoliar) : This substance given as injected form if you have allergic asthma all year round. Suited for individual 12 years and above. If your symptoms are not well controlled by long term asthma drugs then this agent can be effective in reducing frequency of acute asthmatic attack. A prior test dose is give at doctor’s office before full dose. Severe anaphylaxis(extreme to substance) has been reported. You should be observed at doctor’s office for few hours after injection of Xoliar.

·        Allergic medication : cromolyn sodium nasal spray can be used . So are the different anti-histamine available OTC. They prevent and relieve symptoms of rhinitis that can subsequently lead to asthmatic symptoms. Decongestant and corticosteroids nasal are effective in hay fever and common cold. Side effects include, burning and stinging sensation in nose.  Unlikely side effects are headache, dizziness, heart pounding ,sleep trouble, body tremors .