Interrelationship of Platelet Indices, Pulmonary Artery Diameter, and Severity of COPD and Pulmonary Hypertension

Abstract

Objective: The study aimed to evaluate how platelet indices and main pulmonary artery diameter correlate with the severity of chronic obstructive pulmonary disease and pulmonary hypertension.

Methodology: The methodology consisted of a cross-sectional analytical study that included 180 adults with stable COPD. Airflow limitation was graded by post-bronchodilator FEV1 percentage predicted (GOLD 1, 4). Main pulmonary artery diameter was measured on axial chest CT at the level of the pulmonary artery bifurcation; pulmonary artery systolic pressure (PASP) was estimated by transthoracic echocardiography. Platelet count, mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) were recorded. The association with pulmonary hypertension, defined in this study as an estimated pulmonary artery systolic pressure (PASP) of ≥35 mmHg, was assessed using correlation analysis and multivariable logistic regression.

Result: Participants had a mean age of 65.1 ± 7.8 years. Among 180 participants, pulmonary hypertension was identified in 115 (63.9%). Participants with pulmonary hypertension had a greater mean pulmonary artery diameter than those without pulmonary hypertension (31.24 ± 2.57 mm vs. 27.08 ± 2.13 mm, *p* <.001). The pulmonary-hypertension group also exhibited higher values for MPV (8.67 ± 0.78 vs 7.74 ± 0.69 fL, p<.001), PDW, platelet count, and PCT. Pulmonary artery diameter showed a positive correlation with PASP (r=.694, p<.001) and an inverse correlation with FEV1% predicted (r=−.710, p<.001). MPV correlated positively with PASP (r=.625, p<.001) and inversely with FEV1% predicted (r=−.575, p<.001). Multivariable analysis identified higher MPV, larger pulmonary artery diameter, and lower FEV1% predicted as independent predictors of pulmonary hypertension.

Conclusion: Increased severity of COPD was associated with the presence of enlarged pulmonary arteries, high levels of pulmonary pressure estimation, and changes in platelet parameters. MPV and pulmonary artery size were the parameters that showed the most significant relationship to pulmonary hypertension and can be used as additional parameters for the evaluation of pulmonary vessel pathology in COPD. The evaluation of routine platelet parameters, CT pulmonary artery size, severity of COPD, and pulmonary pressure estimation is a practical multimodal approach to assessing pulmonary risk..

Keywords: COPD; pulmonary hypertension; pulmonary artery diameter; mean platelet volume; platelet distribution width; plateletcrit; FEV1.