Frequency of Polycythemia in Chronic Obstructive Pulmonary Disease (COPD) PatientsPresenting to Tertiary Care Hospital

Abstract

Objective: To determine the frequency of polycythemia among chronic obstructive pulmonary disease (COPD) patients and explore its clinical associations.

Study Design: Cross-sectional Study
Place and Duration of Study: This study was conducted at the Department of Medicine, Combined Military Hospital, Abbotabad, Pakistan from September 2025 to April 2026.

Methods: All patients of either gender, age 40 - 80 years, with confirmed diagnosis of COPD based on post- bronchodilator spirometry were included. Spirometry was performed to determine FEV1 % predicted and classify disease severity according to GOLD stages (1–4) and classified patients into GOLD treatment groups (ABE) according to COPD Assessment Test (CAT). Polycythemia frequency was calculated and logistic regression analysis was performed to identify independent predictors of polycythemia in COPD patients.

Results: Two hundred COPD patients with mean age of 49.97 ± 8.20 years including 148 (74.0%) males and 52 (26.0%) females. The frequency of polycythemia was 18.0% with mean resting SpO2 of 89.28 ± 2.53% in
polycythemia group and 90.38 ± 2.71% in non-polycythemia group (p=0.027). The mean partial pressure of carbon dioxide (PaCO2) was 47.36 ± 14.04 mmHg and 47.79 ± 14.00 mmHg in the polycythemia and non-polycythemia group respectively (p=0.866). In contrast, the mean partial pressure of oxygen (PaO2) was higher in patients with polycythemia (72.94 ± 10.11 mmHg) compared to without polycythemia (68.50 ± 10.26 mmHg) (p=0.019).

Conclusion: Polycythemia is common hematological finding in COPD patients having resting hypoxemia with no significant association with age, gender, BMI or smoking duration. However, active smoking and lower resting SpO2 had somewhat influence in patients being polycythemic.