The use of exhaled nitric oxide monitoring in primary care asthma clinics: a pilot study

Abstract

Aim: Although asthma is defined as a chronic inflammatory disease, inflammation is rarely assessed. The fraction of exhaled nitric oxide (FeNO) is a biomarker of airways inflammation. We assessed the feasibility of FeNO monitoring in general practice.Methods: Prospective observational study of volunteers attending primary care asthma clinics. Consenting subjects were seen at their own surgery for 2-weekly reviews over 12 weeks, with assessment of FeNO, lung function, symptoms and health status.Results: 22 adults and 15 children provided informed consent. Two subjects were unable to perform the FeNO expiratory manoeuvre. In the remaining subjects, measurements conforming to highest ERS/ATS recommendations were made on 211 of 236 occasions, and on 21 further occasions acceptable readings were made. Acceptability was high to subjects and staff. Correlations between FeNO readings and other parameters were weak and non-significant except for statistically significant correlation between longitudinal FeNO changes and changes in lung function (r= -0.33, p<0.001) and health status (r= -0.22, p=0.022).Conclusions: Exhaled nitric oxide monitoring is technically feasible and acceptable to staff and patients within the context of a primary care asthma clinic.

Assessing asthma control in routine clinical practice: use of the Royal College of Physicians ‘3 Questions’

“…As part of a pilot study investigating the feasibility of monitoring exhaled nitric oxide levels in general practice asthma clinics reported in this journal recently, 12 we aimed to assess the use of the RCP 3 questions in a routine primary care asthma clinic setting.…”

Summary of the 2008 BTS/SIGN British Guideline on the Management of Asthma

“…1,5 • Tests of airway hyper-responsiveness, including challenge tests, eosinophilic airway inflammation, induced sputum differential eosinophil count, or the fraction of exhaled nitric oxide (Fe N0 ), are currently outside the domain of primary care, apart from a few specialised general practices. 19 Specialist referral is required if these tests are needed.…”

The ADMIT series — Issues in Inhalation Therapy. 1) The goals of asthma treatment: can they be achieved?

“…At present, these markers are not included in routine clinical assessment of control, although measurement of exhaled NO levels is becoming more feasible. 15 Several questionnaires have been developed to measure asthma control -see Table 5. 4 A frequently used example is the Asthma Control Test (ACT) 16 as shown in Table 6.…”