Blood pressure, heart rate, and mortality in chronic obstructive pulmonary disease: the SUMMIT trial

Aims: To characterize the relationship between blood pressure (BP) or heart rate and mortality and morbidity in chronic obstructive pulmonary disease (COPD). Methods and results: We performed post hoc analysis of baseline BP or heart rate and all-cause mortality and cardiovascular events in the SUMMIT trial. SUMMIT was a randomized double-blind outcome trial of 16 485 participants (65 ± 8 years, 75% male, and 47% active smokers) enrolled at 1368 sites in 43 countries. Participants with moderate COPD with or at risk for cardiovascular disease (CVD) were randomized to placebo, long-acting beta agonist, inhaled corticosteroid, or their combination. All-cause mortality increased in relation to high systolic [≥140 mmHg; hazard ratio (HR) 1.27, 95% confidence interval (CI) 1.12-1.45] or diastolic (≥90 mmHg; HR 1.35, 95% CI 1.14-1.59) BP and low systolic (<120 mmHg; HR 1.36, 95% CI 1.13-1.63) or diastolic (<80 mmHg; HR 1.15, 95% CI 1.00-1.32) BP. Higher heart rates (≥80 per minute; HR 1.39, 95% CI 1.21-1.60) and pulse pressures (≥80 mmHg; HR 1.39, 95% CI 1.07-1.80) were more linearly related to increases in all-cause mortality. The risks of cardiovascular events followed similar patterns to all-cause mortality. Similar findings were observed in subgroups of patients without established CVD. Conclusion: A 'U-shaped' relationship between BP and all-cause mortality and cardiovascular events exists in patients with COPD and heightened cardiovascular risk. A linear relationship exists between heart rate and all-cause mortality and cardiovascular events in this population. These findings extend the prognostic importance of BP to this growing group of patients and raise concerns that both high and low BP may pose health risks.