Host transcriptomic signature for viral and bacterial infection at exacerbation of COPD–The longitudinal PAX-I study

Despite being both treatable and preventable, COPD represents one of the major burdens on health-care systems worldwide. Exacerbation are key features in the management of COPD due to their negative impact on hospitalization rates and disease progression. We prospectively explored the association between clinical diagnosis exacerbation and a blood-based 29 mRNA host-response test in patients prior diagnosed with COPD. The PAX-study is a prospective, longitudinal, single-center study involving patients with physician diagnosed COPD confirmed by spirometry. Participants were assessed at stable state and for exacerbation by a respiratory medicine specialist on multiple patient visits. Next to a full clinical characterization including molecular diagnostic for viral agents, blood was analyzed for 29 mRNA host-response using InSep™(Inflammatix,California,USA) at every patient visit. A predicted probability score was calculated using IMX-BVN-2 neural network classifier, higher score depicting higher risk of infection. 123 patients were included for a total of 510 visits. In an interim analysis, the average age of the subjects was 66 ± 8 years and 66.6% were male. The mean FEV1 was 57% ± 13% of predicted value. There was a transitional increase in the combined mRNA host-response score (bacterial and viral) during COPD exacerbation compared to steady state measurements and follow up(0.34vs0.54 vs0.35,p=0.049). As compared to the stable state, there is a significant increase in the mRNA inflammatory host response for infection(bacterial and viral) at COPD exacerbation. Novel serological markers could complement current algorithms of diagnosis and treatment of COPD exacerbations