Prognostic Value of Impaired Spirometry in Patients with Myocardial Infarction: A Longitudinal Study of Two European Cohorts

Purpose: The study aimed to investigate the associations between impaired spirometry such as obstructive pattern and preserved ratio impaired spirometry (PRISm) and occurrent cardiovascular events and deaths in patients with acute myocardial infarction. Patients and Methods: Cohort study of 517 patients with age ≥ 40 years and ≥ 10 pack-years of smoking, hospitalized for myocardial infarction at eight sites in Sweden and the United Kingdom. The Vitalograph ® COPD-6 device was used to assess the ratio of forced expiratory volume in 1 and 6 seconds (FEV 1 /FEV 6 ) and FEV 1 as a percentage of the predicted value (FEV 1 %pred). Obstructive pattern was defined as FEV 1 /FEV 6 < 0.7, PRISm as FEV 1 /FEV 6 > 0.7 and FEV 1 %pred < 80, and normal findings as FEV 1 /FEV 6 ≥ 0.7 and FEV 1 %pred ≥ 80. Follow-up data were obtained from national registers or follow-up visits. Multivariable Cox regression was used to analyze the associations of obstructive pattern and PRISm with the incidence of acute ischemic cardiovascular events or major adverse cardiovascular events (MACE), respectively, within one year. Results: Obstructive pattern was found in 95 (18%), PRISm in 192 (37%) and normal spirometry in 230 (45%) patients. A cardiovascular event occurred in 21 (4%) and MACE in 28 (5%). Compared with normal spirometry, PRISm was independently associated with both new cardiovascular events (HR (95% CI) 3.44 (1.07– 11.0)) and MACE (4.94 (1.63 to 15.0)), and obstructive pattern with MACE (3.87 (1.08– 13.8)). Further adjustment for cardiac or COPD treatment did not substantially change the results. Conclusion: About half of patients with acute myocardial infarction and a ≥ 10 pack-year smoking history have abnormal spirometry findings. Both obstructive pattern and PRISm are independently associated with increased risk for MACE within one year. We suggest that spirometry should be considered as a routine assessment in patients with smoking history and recent myocardial infarction. Plain Language Summary: Impaired spirometry such as obstructive pattern as in chronic obstructive pulmonary disease (COPD) and preserved ratio impaired spirometry (PRISm) are associated with increased risk of mortality in the general populationThe present study investigated the prevalence and associations of obstructive pattern and PRISm with and occurrent cardiovascular events and deaths in patients with acute myocardial infarction, in cohorts from Sweden and the United KingdomWe found that about half of patients with acute myocardial infarction and a ≥ 10 pack-year smoking history have abnormal spirometry findingsIn patients with acute myocardial infarction and a ≥ 10 pack-year smoking history, obstructive pattern and PRISm are both associated with increased one-year risk of occurrent acute ischemic cardiovascular events and cardiovascular deaths Keywords: chronic obstructive pulmonary disease, COPD, obstructive pattern, preserved ratio impaired spirometry, PRISm, acute ischemic cardiovascular events, major adverse cardiovascular events, MACE