Sildenafil for Chronic Obstructive Pulmonary Disease: A Randomized Crossover Trial COPD: Journal of Chronic Obstructive Pulmonary Disease, 05/25/2012

Lederer DJ et al. – Routine sildenafil administration did not have a beneficial effect on exercise capacity in patients with chronic obstructive pulmonary disease (COPD) and emphysema without pulmonary hypertension. Sildenafil significantly worsened gas exchange at rest and quality of life.

• The authors performed a randomized, double–blind, placebo–controlled 2–period crossover trial of sildenafil thrice daily in ten adults with COPD and emphysema on CT scan without pulmonary hypertension.
• The authors randomized study participants to 4 weeks of sildenafil (or placebo) followed by a 1–week washout and then 4 weeks of placebo (or sildenafil).
• The 2 primary outcomes were the 6–minute walk distance and oxygen consumption at peak exercise.

• Sildenafil had no effect on 6–minute walk distance (placebo–corrected difference = –7.8 m, 95% confidence interval, –23.2 to 7.5 m, p = 0.35) or oxygen consumption at peak exercise (placebo–corrected difference = –0.1 ml/kg/min, 95% confidence interval –2.1 to 1.8 ml/kg/min, p = 0.89).
• Sildenafil increased the alveolar–arterial oxygen gradient (p = 0.02), worsened symptoms (p = 0.04), and decreased quality–of–life (p = 0.03).
• Adverse events were more frequent while receiving sildenafil (p = 0.005).