Background COPD ranks third in the leading causes of morbidity and mortality worldwide. Despite this fact, a significant underdiagnosis of the disease remains either due to low awareness on the need for a diagnostic spirometry or no access to spirometry because it is unavailable or expensive. Affordable options utilizing peak expiratory flow rate (PEFR) as a case finding tool for COPD warrants investigation. This study aims to determine the prevalence of participants enrolled in CPASS who have peak flow rate:height ratio of <2.2 L/s/m2.

Methods This is a cross sectional analytical study of COPD patients currently enrolled in the Philippine College of Chest Physician COPD Clinical Profile and Survival Study (CPASS) involving 1982 participants. After determining the prevalence of spirometry-diagnosed COPD patients who have PEFR of <2.2 L/s/m2, post-hoc analyses were made to determine the difference in age, height, weight, body mass index (BMI), GOLD airflow limitation classification and GOLD group classification among those who have and do not have PEFR of < 2.2 L/s/m2.

Results The prevalence of CPASS participants who have PEFR of < 2.2 L/s/m2 is 94.2%. On post-hoc analysis, higher percentage of participants who had low PEFR belong to the older age group, have lower BMI, and have more severe airflow limitation. Greater percentage of participants who have PEFR of < 2.2 L/s/m2 belong to GOLD Groups B and D.

Conclusion With a high sensitivity that is comparable to a multinational study, use of PEFR measurement shows promise as an affordable and efficient case-finding tool for Filipino COPD patients. Accuracy of this parameter will be pursued in another study.