At present, there is some evidence that HRQoL has predictive value for risk of exacerbations, use of health care resources, and mortality in COPD [ 49, 50].
Anthonisen's classification never intended to establish the severity of exacerbation using type of exacerbations (type 1, 2 and 3) but rather which patient could benefit from being treated with antibiotics.
Future developments are likely to include the identification of better biomarkers to predict exacerbations or the cause of exacerbations, augmentation of the immunological response to viruses at the time of the exacerbation, the use of telemonitoring in patients with severe asthma and the development of improved therapies targeted at reducing exacerbations.
ED visits and hospitalizations have each been widely explored in response to short-term changes in air pollution exposures, but each captures a slightly different aspect of asthma exacerbation and use of medical services across sub-populations [ 34].
Finally, associations between asthma (initiation and/or exacerbation) and use of indoor pools by children may be related to the combined influence of chemical irritants and infectious agents (Sattar et al. 2007).
Various outcomes are assessed quarterly and at exacerbation using a series of questionnaires and patient-reported outcome instruments, such as the COPD Assessment Test (CAT), 31 the Nottingham Extended Activities of Daily Living (NEADL) Scale, 32 the Council on Nutrition Appetite Questionnaire (CNAQ) 33 and the EQ-5D.
Irrespective of the definition of exacerbation used, the clinical diagnosis points to an acute clinical worsening that may necessitate a change in regular treatment[ 9].
Our results and methodology will be of immediate interest to those employing domiciliary oximetry to monitor COPD and, with further validation, have the potential to facilitate objective confirmation of exacerbation using simple technology, enabling access to prompt therapy and verification of events in clinical trials.
To be consistent with the Sin et al report of a 50% decrease in acute exacerbations through use of inhaled corticosteroids [ 100, 101], we used a monthly probability of acute exacerbations of.27 for those taking medications and.53 for those not taking medications.
Participants are asked about exacerbations and use of antibiotics or steroids for these.
