Allergic Rhinitis & Its Impact on Asthma

Both asthma and allergic rhinitis are systemic inflammatory conditions that affect both the lower and upper airways. When an individual has both allergic rhinitis and asthma, asthma can be worsened. According to the new "Allergic Rhinitis And Its Impact On Asthma (ARIA)" guidelines, it has been reported that nearly 80 percent of those with asthma are also suffering from rhinitis. However, there have been questions regarding allergic rhinitis and the impact it has on asthma. To answer these questions, many studies have been conducted.

Studies

• The studies that have been conducted have been done in an attempt to show how common allergic rhinitis is in those with asthma and how it affects asthma. For instance, a study conducted in Rochester, Minnesota, showed that allergic rhinitis had a prevalence of 59 percent in those with an asthma diagnoses before the age of 25. In those diagnosed with asthma after the age of 40, only 15 percent had allergic rhinitis.

  Studies have also shown that a geographical difference may exist. For example, the prevalence of allergic rhinitis in residents of rural China was below 6 percent. The medical community is working to understand this, but factors such as pollen, animal and mite sensitivity may have an impact on why allergic rhinitis affects individuals in some geographical areas more than others. An understanding of this may help in the treatment and the prevention of rhinitis in asthma patients.

Impact

• The diagnosis of allergic rhinitis frequently comes before a diagnosis of asthma. Rhinitis usually causes bronchial hyperresponsiveness, even if no asthma is present, but is associated with an increased risk of developing asthma within four to five years. In those asthma patients who experience nasal symptoms with allergic rhinitis, there is an increased risk of asthma worsening versus those who do not have nasal symptoms.

  Furthermore, cost of illness studies have shown an increase in health care costs for patients with both asthma and allergic rhinitis. UK Medi-Plus general practice database studies have also shown a 50 percent increase in hospitalizations for asthma amongst adults. This percentage increases to 250 percent for children, and it is proven that both age groups have shown an increase in the prescribing frequency of asthma medications.

Outcome

• In all controlled trial settings studying the impact of allergic rhinitis on asthma, the outcome for asthma patients is worse than those who do not have rhinitis. More health care resources are required and health care costs are increased. This is because asthma symptoms are more severe when allergic rhinitis is present.