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Rationale: Patients with chronic obstructive pulmonary disease (COPD) have elevated cardiovascular risk, and myocardial injury is common during severe exacerbations. Little is known about the prevalence, magnitude, and underlying mechanisms of cardiovascular risk in community-treated exacerbations. Objectives: To investigate how COPD exacerbations and exacerbation frequency impact cardiovascular risk and myocardial injury, and whether this is related to airway infection and inflammation. Methods: We prospectively measured arterial stiffness (aortic pulse wave velocity [aPWV]) and cardiac biomarkers in 98 patients with stable COPD. Fifty-five patients had paired stable and exacerbation assessments, repeated at Days 3, 7, 14, and 35 during recovery. Airway infection was identified using polymerase chain reaction. Measurements and Main Results: COPD exacerbation frequency was related to stable-state arterial stiffness (rho = 0.209; P = 0.040). Frequent exacerbators had greater aPWV than infrequent exacerbators (mean ± SD aPWV, 11.4 ± 2.1 vs. 10.3 ± 2.0 ms−1; P = 0.025). Arterial stiffness rose by an average of 1.2 ms−1 (11.1%) from stable state to exacerbation (n = 55) and fell slowly during recovery. In those with airway infection at exacerbation (n = 24) this rise was greater (1.4 ± 1.6 vs. 0.7 ± 1.3 ms−1; P = 0.048); prolonged; and related to sputum IL-6 (rho = 0.753; P < 0.001). Increases in cardiac biomarkers at exacerbation were higher in those with ischemic heart disease (n = 12) than those without (n = 43) (mean ± SD increase in troponin T, 0.011 ± 0.009 vs. 0.003 ± 0.006 μg/L, P = 0.003; N-terminal pro–brain natriuretic peptide, 38.1 ± 37.7 vs. 5.9 ± 12.3 pg/ml, P < 0.001). Conclusions: Frequent COPD exacerbators have greater arterial stiffness than infrequent exacerbators. Arterial stiffness rises acutely during COPD exacerbations, particularly with airway infection. Increases in arterial stiffness are related to inflammation, and are slow to recover. Myocardial injury is common and clinically significant during COPD exacerbations, particularly in those with underlying ischemic heart disease.

Background The ability to objectively differentiate exacerbations of chronic obstructive pulmonary disease (COPD) from day-to-day symptom variations would be an important development in clinical practice and research. We assessed the ability of domiciliary pulse oximetry to achieve this. Methods 40 patients with moderate-severe COPD collected daily data on changes in symptoms, heart-rate (HR), oxygen saturation (SpO2) and peak-expiratory flow (PEF) over a total of 2705 days. 31 patients had data suitable for baseline analysis, and 13 patients experienced an exacerbation. Data were expressed as multiples of the standard deviation (SD) observed from each patient when stable. Results In stable COPD, the SD for HR, SpO2 and PEF were approximately 5 min-1, 1% and 10l min-1. There were detectable changes in all three variables just prior to exacerbation onset, greatest 2-3 days following symptom onset. A composite Oximetry Score (mean magnitude of SpO2 fall and HR rise) distinguished exacerbation onset from symptom variation (area under receiver-operating characteristic curve, AUC = 0.832, 95%CI 0.735-0.929, p = 0.003). In the presence of symptoms, a change in Score of ≥1 (average of ≥1SD change in both HR and SpO2) was 71% sensitive and 74% specific for exacerbation onset. Conclusion We have defined normal variation of pulse oximetry variables in a small sample of patients with COPD. A composite HR and SpO2 score distinguished exacerbation onset from symptom variation, potentially facilitating prompt therapy and providing validation of such events in clinical trials.

Background Exacerbations of non-cystic fibrosis bronchiectasis cause significant morbidity but there are few detailed data on their clinical course and associated physiological changes. The biology of an exacerbation has not been previously described. The purpose of this study was to describe changes in lung function, symptoms, health status and inflammation during the development and recovery from community-treated exacerbations. Methods This was a prospective observational cohort study of 32 outpatients with non-cystic fibrosis bronchiectasis conducted between August 2010 and August 2012. Patients completed a symptom diary card and measured their peak expiratory flow rate (PEFR) daily. Exacerbations were defined as oral antibiotic treatment taken for a worsening of respiratory symptoms. Symptoms and peak flow at exacerbation were analysed, and further measurements including the COPD Assessment Test (CAT) and inflammatory markers were also compared to baseline values. Results At baseline, health status was significantly related to lung function, prognostic severity and systemic inflammation. 51 exacerbations occurred in 22 patients. Exacerbation symptoms began a median (interquartile range) of 4 (2, 7) days before treatment started and the median exacerbation duration was 16 (10, 29) days. 16% had not recovered by 35 days. At exacerbation, mean PEFR dropped by 10.6% (95% confidence interval 6.9-14.2, p