Occupational asthma: Treatment, symptoms, advice and help
About occupational asthma
Asthma is an obstructive lung disease characterised by recurrent episodes of cough and breathlessness. It results from the inflammation and swelling of oversensitive airways on exposure to allergens and irritants. Occupational asthma is a term used for occurrence of asthma for the first time in adulthood or re-appearance of childhood asthma. This kind of asthma is generally seen in response to allergens or irritants at the workplace.
Occupational asthma: Incidence, age and sex
Occupational asthma is not an uncommon occurrence in the general population. It is more prevalent in industrialized nations as compared with developing countries.
Signs and symptoms of occupational asthma: Diagnosis
Occupational asthma can be of two types, namely ‘hypersensitivity induced’ or ‘acute irritant induced’. The majority of affected individuals fall into the category of ‘hypersensitivity induced asthma’ in which the individual develops asthma after a prolonged time period of exposure to the allergen. On the other hand, ‘acute irritant induced asthma’ is seldom encountered and characterised by appearance of asthma within a short time period of exposure of allergens.
The clinical features of asthma may vary from mild to severe to acute exacerbations. Clinical features include recurring cough, shortness of breath and chest tightness. Some individuals may also have wheezing which is a whistle-like sound produced on exhaling air. These symptoms may be more pronounced at night or early morning.
The typical clinical features help in detecting this condition. Disappearance of asthmatic features when away from work for a substantial period of time and their subsequent reappearance on returning to workplace corroborates the diagnosis of occupational asthma. Certain investigations like PEF (peak expiratory flow) and bronchial provocation test may also be considered.
Causes and prevention of occupational asthma
The chief basis contributing to asthma is increased sensitivity of the airways to certain triggering factors which leads to increased mucus secretions and swelling of the airways, resulting in constricting them. Occupational asthma can be caused by exposure to various allergens including chemicals, plant and animal products. Following workers are more susceptible to development of occupational asthma:
Poultry farmers from feathers and animal droppings
Bakers from flour
Health care providers including veterinarians from latex, dander, formalin
Refinery workers from platinum salts
Workers in automobile industry from dissocyanates
Workers in plastic industry, rubber industry and silk industry.
Cessation of smoking or patient awareness regarding occupational asthma may help in preventing worsening of asthmatic symptoms.
Occupational asthma: Complications
Poor control of asthma may increase chances of acute exacerbations which may be potentially fatal. Moreover switching jobs due to occurrence of occupational asthma may have financial and social implications for the individual.
Occupational asthma: Treatment
Asthma is a treatable disease but unfortunately it cannot be cured. Asthmatic patients are required to take controller medications (slow acting drugs) regularly. Reliever medications (fast acting drugs) are needed for immediate relief of asthmatic symptoms. They are short acting and their function is to dilate the constricted air passages. These asthmatic medications are given by inhaler devices called nebuliser or inhaler. In resistant cases, where asthma remains uncontrolled, oral steroids may be prescribed for better control. A recent advancement in treatment, called immunotherapy, may also be considered in individuals whose asthma is not controlled with medications. However, the best treatment in occupational asthma is to switch jobs and work in a place where there may be lesser or no exposure to the offending allergen.