Comprehensive assessments of exercise capacity and quality of life (QoL) can be used to predict 2-year mortality in patients with pulmonary arterial hypertension (PAH), according to study results published in the Taiwanese journal Acta Cardiologica Sinica, the official journal of the Taiwan Society of Cardiology.
Investigators sought to evaluate correlations in exercise capacity, QoL, and disease functional classification, as well as to examine the value of comprehensive assessments in predicting mortality in patients with PAH. A total of 54 patients with PAH (51 women and 3 men) were enrolled in the study. The participants were all classified with group 1 PAH according to the World Health Organization (WHO) classification of PH. Of the total study population, 25 patients were classified with WHO functional class (FC) II, 24 were classified with WHO FC III, and 5 were classified with WHO FC IV.
All participants were evaluated for exercise capacity by using the 6-minute walk test (6MWT) and the cardiopulmonary exercise test. These tests are known to be associated with physical function, QoL, and hemodynamic data in patients with PAH. Health-related QoL was assessed using the Chinese version of the Short Form 36 (SF-36) questionnaire. All of the participants were followed for 2 years, with an end point of mortality.
Survivors with PAH had a significantly lower WHO FC (P <.001), lower systolic pulmonary arterial pressure (P =.001), longer 6MWT distance (P =.042), higher peak oxygen uptake (VO2; P <.001), higher oxygen uptake at anaerobic threshold (P =.0001), and higher physical component score (PCS) on the SF-36 (P =.038), compared with those who died.
Moreover, exercise capacity combined with the SF-36 predicted 2-year mortality in patients with PAH. Participants with lower peak VO2 (ie, <11.03 mL/kg/min) and lower PCS (<44.54) had a significantly higher rate of mortality compared with those with a higher peak VO2 and a higher PCS (adjusted hazard ratio, 19.95; P =.011).
Major limitations of the study included the small sample size and predominance of female participants. Moreover, other underlying diseases that might contribute to disease-related mortality in this study population were not recorded.
The investigators concluded that exercise capacity and the physical component of the SF-36 differed in the survivors and the nonsurvivors with PAH. Such comprehensive evaluations using exercise capacity and QoL can be used to predict 2-year mortality in patients with PAH.
Chen Y-J, Tu H-P, Lee C-L, et al. Comprehensive exercise capacity and quality of life assessments predict mortality in patients with pulmonary arterial hypertension.Acta Cardiol Sin. 2019;35(1):55-64.