The increased HF risk associated with reduced FEV1 in this study was not explained by established HF risk factors known to be associated with lung function, including LVH and AF,29–31 which is consistent with findings from the Cardiovascular Health Study.12 The association between FEV1 and HF was independent of inflammatory markers CRP and interleukin-6 and adjustment for incident CHD did not alter the findings as shown in other studies.12, 14, 15 Shortness of breath and low lung function is a symptom of both COPD and HF. Here, IL6 is linked to atrial fibrillation.