Effect of pulmonary hypertension on exercise tolerance in patients with COPD: a prognostic systematic review and meta-analysis.

Torres-Castro R; Gimeno-Santos E; Vilaró J; Roqué-Figuls M; Moisés J; Vasconcello-Castillo L; Orizaga T; Barberà JA; Blanco I;

European respiratory review : an official journal of the European Respiratory Society [Eur Respir Rev] 2021 Apr 29; Vol. 30 (160). Date of Electronic Publication: 2021 Apr 29 (Print Publication: 2021).

Background: Pulmonary hypertension (PH) is a frequent complication in patients with COPD.
Objective: To determine if, in patients with COPD, the presence of PH decreases exercise tolerance.
Methods: We included studies that analysed exercise tolerance using a cardiopulmonary exercise test (CPET) in patients with COPD with PH (COPD-PH) and without PH (COPD-nonPH). Two independent reviewers analysed the studies, extracted the data and assessed the quality of the evidence.
Results: Of the 4915 articles initially identified, seven reported 257 patients with COPD-PH and 404 patients with COPD-nonPH. The COPD-PH group showed differences in peak oxygen consumption ( VO 2peak ), -3.09 mL·kg -1 ·min -1 (95% CI -4.74 to -1.43, p=0.0003); maximum workload (W max ), -20.5 W (95% CI -34.4 to -6.5, p=0.004); and oxygen pulse (O 2 pulse), -1.24 mL·beat -1 (95% CI -2.40 to -0.09, p=0.03), in comparison to the group with COPD-nonPH. If we excluded studies with lung transplant candidates, the sensitivity analyses showed even bigger differences: VO 2 , -4.26 mL·min -1 ·kg -1 (95% CI -5.50 to -3.02 mL·kg -1 ·min -1 , p<0.00001); W max , -26.6 W (95% CI -32.1 to -21.1 W, p<0.00001); and O 2 pulse, -2.04 mL·beat -1 (95% CI -2.92 to -1.15 mL·beat -1 , p<0.0001).
Conclusion: Exercise tolerance was significantly lower in patients with COPD-PH than in patients with COPD-nonPH, particularly in nontransplant candidates.