Rhinitis/sinusitis and asthma relationship is a "two-way street"

The upper and lower airways do not exist as separate units both neither anatomically nor functionally.


Nose and nasal cavities. Image source: Wikipedia, public domain.

There is a 2-way relationship between the nose/sinuses and lower airway:

1. Allergic rhinitis and rhinosinusitis may impact asthma and those patients should be monitored for development of asthma.

2. Patients with asthma should be considered to have either rhinitis or rhinosinusitis.


Left-sided maxillar sinusitis (absence of the air transparency of left maxillar sinus). Image source: Wikipedia, public domain.

The 1999 WHO workshop ‘Allergic Rhinitis and its Impact on Asthma’ recommended:

- patients with persistent allergic rhinitis should be evaluated for asthma by history, chest examination, and possibly assessment of airflow obstruction before and after bronchodilator

- history and examination of the upper respiratory tract for allergic rhinitis should be performed in patients with asthma

References:

The upper and lower airways: The epidemiological and pathophysiological connection. Slavin, Raymond G. Allergy and Asthma Proceedings, Volume 29, Number 6, 11/12 2008 , pp. 553-556(4).
More than a "runny nose" - allergic rhinitis and asthma
Poor asthma control? – then look up the nose. The importance of co-morbid rhinitis in patients with asthma http://goo.gl/0nNZg

Adult Sinusitis: A Short Review
United airways again: high prevalence of rhinosinusitis and nasal polyps in bronchiectasis. Guilemany JM, Angrill J, Alobid I, Centellas S, Pujols L, Bartra J, Bernal-Sprekelsen M, Valero A, Picado C, Mullol J. Allergy. 2009 Feb 6.

Multi-symptom Asthma is Closely Related to Nasal Blockage, Rhinorrhea and Symptoms of Chronic Rhinosinusitis http://goo.gl/sU4AU
Staphylococcus aureus biofilm and and superantigens are associated with chronic sinusitis, cause T-helper 2 skewing http://bit.ly/ngnxBe
Rhinitis is common in asthma and impairs asthma control. Allergy. 2011.