Biomedical Engineering Reference
In-Depth Information
17
Mechanisms of Exacerbations
of Chronic Obstructive Pulmonary
Disease
Jadwiga A. Wedzicha
Academic Respiratory Medicine, St. Bartholomew's and Royal London
School of Medicine and Dentistry, Dominion House, St. Bartholomew's
Hospital, West Smithfield, London, U.K.
I.
INTRODUCTION
There is an increasing interest in the causes and mechanisms of exacerba-
tions of chronic obstructive pulmonary disease (COPD), as exacerbations
are an important cause of the considerable morbidity and mortality that
occur in COPD (1). Exacerbations are defined by a worsening symptom
from the usual stable state, especially the symptoms of dyspnoea, increased
sputum amount, and purulence. COPD exacerbations are associated
with increased airway inflammation, with a particular
increase
in
neutrophils.
Some patients are prone to frequent exacerbations that are an impor-
tant cause of hospital admission and readmission, and these frequent exacer-
bations may have considerable impact on quality of life, activities of daily
living, and disease progression (1,2). An understanding of the mechanisms
of exacerbations is important as therapies need to be developed that
can reduce exacerbation frequency. Exacerbations are also associated with
a number of triggers e.g., respiratory viruses or bacteria and these are
important factors in modulating the airway inflammation that occurs at
exacerbation.
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