Asthma | December 15, 2015 | Author: The Super Pharmacist
Brief: Detail the risk factors and possible causes of adult onset asthma. What lifestyle modifications are recommended? What treatments are appropriate? Are these medications taken for the rest of life? Asthma is a disease characterised by increased responsiveness of the airways to various stimuli including allergens and irritants that cause obstruction. The constriction of muscles around the airway, and its inflammation, results in a higher than average secretion of mucous which results in difficulty breathing and increased coughing. Typical causes of asthma include infection, allergens, exercise and air pollution. People who have asthma may experience wheezing, coughing, shortness of breath, and chest tightness. Asthma typically begins early in life, although it can occur at any stage. Asthma that occurs later in life is known as adult onset asthma. Adult onset asthma, or late onset asthma, is asthma that first manifests in adulthood. Prevalence in Australia varies by region and area, but the national asthma prevalence rate stands at two million – 10% of the total population (1). The data also reveals that there were almost 450 asthma related deaths in Australia in 2010, with the majority of deaths occurring in patients over the age of 65. The risk of dying has been evidenced to increase with age (2), and it is significantly more prevalent in areas of socioeconomic deprivation (3). Women are much likelier to develop asthma after the age of 20 than men, although the reasons for this remain contested and unclear (4). Adult onset asthma is not the same as asthma that returns in adulthood having seemingly disappeared in adolescence – this is also common and affects around 35-40% of adults who have experienced asthma as a child, returning in varying degrees of severity.
Unlike most childhood asthma, adult onset asthma is significantly less likely to be triggered by allergies such as animals, pollen and dust mites (5). It is much more likely to be triggered by a range of other factors such as flu, viral infections, heightened emotions (such as laughing or feeling stressed), cigarette smoke or air pollution, hormonal changes, working conditions, exercise and hormonal changes. A large majority of adult onset asthma is attributed to, or worsened by, workplace conditions. This is commonly referred to as workplace asthma. An estimated 5-35% of adult onset asthma/asthma exacerbations in adults are attributed to the workplace (5), and a wide range of professions contain agents or triggers that increase the risk of asthma. Activities that involve exposure to a number of chemicals or ingredients such as soldering flux or latex, spray painting, working with animals, welding and handling timber can all significantly increase the chance of developing asthma. (6) Smoking doesn’t strictly cause adult onset asthma, although individuals who do smoke or are regularly exposed to cigarette smoke may have their asthma provoked as a result.
The symptoms are typical of asthma symptoms in the wider population – tightness or pressure in the chest, a shortness of breath after physical exercise, difficulty breathing, a dry cough (especially at night), prolonged chesty colds and wheezing when exhaling. Because of the similarity of it symptoms with other conditions, adult onset asthma can mimic a range of other health conditions such as Chronic Obstructive Pulmonary Disease (COPD). COPD, including emphysema and chronic bronchitis, is particularly common in older adults (especially those that have smoked). Asthma like symptoms are also present in heart failure, hiatal hernia, stomach problems and rheumatic arthritis, so a thorough examination is undertaken in adults who prevent with late onset asthma.
As there is no cure, effective management of adult onset asthma is required to improve symptoms (7). The evidence shows that patients who design an asthma management action plan are four times less likely to be admitted to hospital with an asthma-related condition than individuals with no plan (8). A typical plan will have three separate components: testing to assess the severity of symptoms, reducing unnecessary exposure to allergens, and the use of appropriate medications. However, a recent survey revealed that only 21% of Australian patients living with asthma had a care plan (9). Eliminating exposure to triggers such as cigarette smoke, aspirin or pet dander is the most effective treatment for asthma. Medication for adult onset asthma is divided into symptom relief (to treat acute symptoms) and long term control (to prevent further exacerbation). Short-acting beta2-adrenoceptor agonists (commonly referred to as SABA) are the accepted first line treatments for asthma symptoms. Some medications that were previously more commonly prescribed such as inhaled adrenaline are no longer recommended due to concerns regarding their role in excessive cardiac stimulation (10). These medications are not usually taken over a longer period of time, with corticosteroids generally considered to be the most effective treatment option available for the long term control and management of asthma and its symptoms. Patients with adult onset asthma who are unable to control their asthma effectively through the use of inhaled corticosteroids alone have the option of taking them with long-acting beta-adrenoceptor agnoists (LABAs) such as formoterol. A systematic review of combined therapies has evidenced that they are generally more effective in adults with severe asthma (11), although taken without corticosteroids they can increase the risk of severe side effects (12). The length of time that individuals need to take medication will often depend on the severity of their asthma and how well they respond to particular treatments.