Respiratory diseases

Respiratory Diseases

The PHARMO Respiratory Cohort includes all patients with asthma and/or COPD from the PHARMO Database Network. Patients from both the GP Database and the Out-patient Pharmacy Database are included, resulting in over 300.000 patients with asthma, over 160.000 patients with COPD and almost 34.000 patients with the double diagnosis asthma and COPD.

Patients from the GP Database are included based on GP recorded information (ICPC code, a diagnosis recorded as free text or a GP examination) and patients from the Outpatient Pharmacy Database are included based on a validated algorithm developed by the PHARMO Institute (taking age, gender, use of R01 medication, use of R03 medication, duration of use, prescriber and number of prescriptions into account). An algorithm is developed, because patients with COPD and asthma use the same medication and the indication of use is not reported in the Out-patient Pharmacy Database. Please contact us for more information on this algorithm.

Information is available regarding respiratory medication use, socioeconomic status, lifestyle factors (e.g. smoking status, body mass index), exacerbations, disease severity, and disease symptoms.

Exacerbations can be divided in moderate and severe exacerbations. Moderate exacerbations are based on medication use and usually defined as a prescription/dispensing for a systemic antibiotic and/or OCS. Severe exacerbations are usually based on hospitalisations. Furthermore, GPs also record the number of exacerbations in the last year with a standard test.

Disease severity is based on lung function tests (FEV1% predicted) and on information as recorded by the GP (intermittent or persistent asthma , GOLD scale for COPD).

Information regarding disease symptoms is available in the GP Database and includes the validated Asthma Control Questionnaire (ACQ)1 or childhood ACQ (c-ACQ)2, the Clinical COPD Questionnaire (CCQ)3 and the Medical Research Council (MRC)4 breathlessness scale.

As is well known, diagnostic confusion between COPD and asthma is common. Therefore, results regarding the PHARMO Respiratory Cohort should always be interpreted by our database experts with extensive knowledge of the field and context of the results.  For more information on the expertise of our researchers, please click here.

Overall, the PHARMO Respiratory Cohort is a large cohort with long follow-up period. Because this cohort can be updated yearly, the data will become more enriched as more patients will be included, patients can be followed for a longer period and more information will be available. The PHARMO Respiratory Cohort is suitable for several kinds of pharmaco-epidemiological study questions regarding asthma and/or COPD.


  1. 1. Juniper EF, O’Byrne PM, Guyatt GH, et al. Development and validation of a questionnaire to measure asthma control. Eur Respir J, 1999: 14; 902-907
  2. 2. Juniper EF, Gruffydd-Jones K, Ward S, et al. Asthma Control Questionnaire in children: validation, measurement properties, interpretation. Eur Respir J, 2010: 36; 1410-1416
  3. 3. Ställberg B, Nokela M, Ehrs PO, et al. Validation of the clinical COPD Questionnaire (CCQ) in primary care. Health Qual Life Outcomes, 2009: 7; 26
  4. 4. Stenton C. The MRC breathlessness scale. Occup Med, 2008: 58; 226-227