Identification of exacerbations in obstructive lung disease through biomarkers

Abstract

Inflammation has been identified as an important factor for disease exacerbation in obstructive lung disease. In this study, we used neutrophil and eosinophil counts as biomarkers for exacerbation in obstructive lung disease. We conducted a case–control study within a cohort of patients frequenting an outpatient clinic of Respiratory Medicine using data from the Utrecht Patient Oriented Database (UPOD). Cases were patients with a hospital admission for obstructive lung disease in 2005. For each case, one control patient was sampled from the same study base. We identified 143 cases (118 patients with chronic obstructive pulmonary disease and 25 asthma patients) and 143 controls. Admission was associated with both neutrophilia (adjusted odds ratio (OR) 4.3; 95% confidence interval (CI) 2.2–8.5), and eosinophilia (adjusted OR 2.6; 95% CI 1.1–6.2). The association with eosinophilia was only seen in asthma patients. In conclusion, neutrophil and eosinophil counts seem to be useful biomarkers for identifying exacerbations in pharmacoepidemiological studies on obstructive lung disease.

Keywords::

• Eosinophil
• exacerbation
• hospital admission
• molecular epidemiology
• neutrophil
• obstructive lung disease

Acknowledgements

The authors are grateful to Pieter Zanen, for providing the data on the lung function measurements.

Declaration of interest: None of the authors report a personal conflict of interest. The division of Pharmacoepidemiology & Pharmacotherapy employing authors K.J.V., P.C.S., M.J.B., H.G.M.L. and W.W.S. has received unrestricted funding for pharmacoepidemiological research from GlaxoSmithKline, Novo Nordisk, the private–public funded Top Institute Pharma (www.tipharma.nl; includes co-funding from universities, government, and industry), the Dutch Medicines Evaluation Board, and the Dutch Ministry of Health.