Allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa, typified by symptoms of nasal itch, sneeze,…
Allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa, typified by symptoms of nasal itch, sneeze, anterior nasal secretions and nasal blockage. Asthma, on the other hand, is a chronic, inflammatory pulmonary disorder characterised by reversible obstruction of the airways, causing recurrent episodes of wheezing, breathlessness, chest tightness and cough.
Asthma and perennial allergic rhinitis frequently co-exist (Leynaert et al, 1999). Both diseases share similar triggers and similar pathophysiology (Gaga et al, 2000). Corren et al (1992) showed that allergen challenge in the nose led to hyper-responsiveness in the lungs, while another study (Braunstahl et al, 2000), showed that allergen challenge in the lung led to inflammation in the nose.
Evidence supporting an asthma and allergic rhinitis link
A study completed after a 23-year follow-up in 690 college students suggested that patients with AR are three times more likely than those who do not have it to develop asthma (Settipane et al, 1994). Poorly controlled AR has been associated with sub-optimally controlled asthma.
In a survey carried out between 2001 and 2002 of 7,129 patients with asthma, 76% reported symptoms of rhinitis and 49% reported that nasal symptoms worsened their asthma (Walker and Sheikh, 2005). Retrospective studies show that the presence of allergic rhinitis increased the risk of asthma attacks and the risk of emergency hospitalisation in patients with asthma (Price et al, 2005; Thomas et al 2005).
In children, the presence of significant, co-morbid allergic rhinitis more than doubled the chances of hospitalisation compared with children with asthma alone (Thomas et al, 2005). In a study of 7,643 children who had asthma alone compared to 1,879 with asthma and allergic rhinitis, the rates of hospitalisation were 0.5% and 1.4%, respectively (Thomas et al, 2005).
Although the relationship between asthma and AR has long been observed in epidemiological studies (Leynaert et al, 1999), recent data suggests these amount to a clinically important association in terms of asthma control (Price et al, 2005; Thomas et al, 2005).
Asthma guidelines from the British Thoracic Society and the Scottish Intercollegiate Guidelines Network (BTS, SIGN, 2004) have referred minimally to the importance of rhinitis in patients with asthma. However, new international guidelines published in 2006 written by primary care health professionals (Price et al 2006), suggest that optimal management of rhinitis may improve co-existing asthma and that failure to treat rhinitis adequately in those with asthma may make the asthma more difficult to control. In this context, a ‘one disease, one airway’ approach may provide a logical treatment strategy in patients with co-existing asthma and AR.
Classification of allergic rhinitis
AR can be classified as intermittent or persistent. Intermittent AR is often caused by allergens present at certain times of the year and may also be referred to as seasonal allergic rhinitis (SAR).
The most common time for SAR in Britain is from the end of May to July, when grass pollen peaks. SAR is referred to colloquially as ‘hay fever’. Tree pollens are the usual trigger for AR earlier in the year, while spores released from moulds in the autumn are the trigger for symptoms later in the year.
Indoor triggers, such as pets and house-dust mites, are more likely to be responsible for persistent rhinitis, as they are present all the time. Persistent and intermittent AR is further divided into mild or moderate-severe, depending on symptoms and quality of life.
Diagnosis of allergic rhinitis
History AR is defined clinically as a symptomatic disorder of the nose induced by an IgE-mediated inflammation after exposure of the membranes of the nose to an allergen (BTS, SIGN, 2004).
Taking a detailed history of past and current symptoms is the cornerstone of making a diagnosis of AR.
Questions should be asked regarding smoking, occupation, hobbies, known allergies or family history of atopy and any relevant past or current medications, including those bought over the counter.
Typical symptoms of AR include:
- Watery nasal discharge (rhinorrhoea);
- Nasal itching;
- Nasal blockage.
Patients who have two or more of these symptoms lasting for at least one hour on most days are considered to have AR. Diagnosis is usually based on a typical history of these allergic symptoms (BTS, SIGN, 2004). Examination Examination of the nose using an auriscope is recommended to exclude any structural problems. In AR, the nasal mucosa will typically look inflamed and swollen. Symptoms should be bilateral. Although more serious problems, such as carcinoma, are rare they may present as a unilateral blockage or discharge and must be excluded.
Allergy testing This is not essential in the diagnosis and management of AR and may not be available. However, positive skin prick tests may help to reinforce advice on avoidance of triggers and the use of medication (BTS, SIGN, 2004).
Management of allergic rhinitis
Wherever possible, the triggers of AR should be avoided. In reality, this is not always possible and many patients need drug treatment to help control their symptoms.
Antihistamines - These are commonly used as first-line treatment in the management of AR. They have a rapid onset of action and work by blocking H1 receptors (BTS, SIGN, 2004). The second generation antihistamines are preferred by the WHO 1999 guideline, Allergic Rhinitis and its Impact on Asthma (ARIA) (2001), as most of them generally have an improved safety profile, a faster onset of action and are less sedating. Some antihistamines are also available as topical nasal sprays and eye drops.
Antihistamines are especially effective in patients whose main symptoms are palatal itch, sneeze, rhinorrhoea or eye symptoms. They have little effect on nasal blockage.
Nasal corticosteroids - Topical corticosteroids, such as beclometasone, budesonide, fluticasone and mometasone are the most effective pharmacological agents of AR (BTS, SIGN, 2004). They give relief from all its nasal symptoms, including nasal congestion. Patients should be taught how to administer the nasal spray correctly and advised to use it on a regular basis - usually twice daily - although some preparations can be used once daily.
Ideally, nasal steroids should be started two weeks before exposure to a known allergen or trigger and continued on a regular basis. Poor technique and intermittent use are common causes for treatment failure.
Although systemic absorption is thought to be minimal in adults, extra care should be taken with children, and especially in patients using other corticosteroid preparations such as high-dose inhalers for asthma and those who apply heavily potent steroid creams or ointments for eczema. Nasal irritation and sometimes bleeding are possible minor side-effects.
Chromones - The mechanism of these preparations is not fully understood, but they are useful as an alternative for some patients, especially as they have an excellent safety profile. Their disadvantage is that they have a slow onset and short duration of action.
Oral corticosteroids - These, prednisolone, for example, are not usually recommended unless other therapies have been tried and symptoms are still severe.
Immunotherapy - This is not usually considered unless all other treatments have been tried. Commonly known as ‘de-sensitisation’, immunotherapy involves repeated injection, usually given subcutaneously, of a specific allergen. It is important that the procedure is performed only in specialist centres under very careful supervision.
Management of AR and asthma
The aim of the ARIA guidelines (ARIA, 2001) was to create evidence-based approaches to optimise the management of allergic rhinitis and asthma. They recommend that patients with asthma be evaluated for allergic rhinitis and vice-versa, and support a combined approach to treating both conditions.
These guidelines, together with others from the International Primary Care Airways Group (IPCAG, 2005), give evidence-based advice on how best to treat asthma and allergic rhinitis, and are currently the best resource for nurses looking to improve the management of patients who have co-morbid disease.
The British Society for Allergy and Clinical Immunology (BSACI) is updating its guidelines on rhinitis. These are due to be published on its website some time later this year (www.bsaci.org).
The General Practice Airways Group (GPIAG) and Allergy UK have developed a simple allergic rhinitis and asthma status measure to provide support for primary care health professionals conducting asthma reviews. This is a six-point checklist that asks questions about asthma and nasal symptoms (Box 1). A section on interpreting the result guides healthcare professionals as to whether or not asthma is well controlled and if allergic rhinitis is present.
If asthma is poorly controlled in the presence of allergic rhinitis, healthcare professionals are advised to check the use of prescribed medication, inhaler technique and asthma triggers, then to review preventer medication, and consider management of both asthma and allergic rhinitis. The tool is available via the GPIAG website: www.gpiag.org.
Some medications, for example, glucocortico- steroids and leukotriene antagonists, are effective against both allergic rhinitis and asthma symptoms (Price et al, 2006). Patients with both conditions may be prescribed intranasal and inhaled glucocorticosteroids if symptoms warrant, but care should be paid to the total dose they are prescribed.
Patients who have worsening asthma symptoms as well as AR may benefit from a trial of leukotriene antagonist preparations. Currently, the established oral treatment for asthma - montelukast - is licensed in the UK for the control of both mild to moderate asthma and for the relief of seasonal allergic rhinitis in adult asthma patients inadequately controlled on inhaled corticosteroids and short-acting beta-agonists.
Allergic rhinitis and asthma are respiratory diseases that, if poorly managed, result in significant morbidity and lowered quality of life. Allergic rhinitis is sometimes viewed as being a trivial disease, but it has been associated as a predisposing factor for asthma development and the worsening of asthma symptoms. Indeed, around three-quarters of asthma patients also have rhinitis.
Allergic rhinitis increases morbidity, therapeutic needs and the use of healthcare resources in patients with asthma. Optimal management of rhinitis and asthma - if there is co-morbidity in a patient - should focus on unified management strategies.