Pulmonary function among rural residents in high air pollution area in northern Thailand

Abstract

Background: Air pollution has become a serious environmental and health issue in several countries. This condition leads to respiratory diseases, particularly asthma and chronic obstructive pulmonary disease (COPD). This study aimed to determine pulmonary functions and prevalence of respiratory diseases among rural residents in an area in northern Thailand with a high concentration of air pollution. Methods: A cross-sectional study was conducted in people aged 18 years or older, living in Lamphun, Thailand in December 2021. Demographics, pre-existing diseases, respiratory symptoms, and pulmonary functions by spirometry including forced vital capacity (FVC), forced expiratory volume in one second (FEV 1 ), peak expiration flow (PEF), forced expiration flow rate at 25-75% of FVC ( FEF 25-75 ), and bronchodilator responsiveness (BDR; FEV 1 improvement after BDR test >12% and 200 mL) were collected. Results: A total of 127 people (78.7%male) were included. Mean age was 43.76±11.32 years. Smoking was 52.0% and 4.44±5.45 pack-years. Self-reported respiratory diseases were allergic rhinitis (7.1%), asthma (0.8%), and COPD (0.8%). Respiratory symptoms were presented in 33.1% (14.2% runny nose, 10.2% nasal obstruction, 9.4% cough, 7.9% sputum production, and 6.3% breathlessness). Lung functions showed FVC in 96.74±12.91%, FEV 1 in 97.52±12.99%, PEF in 102.46±19.18%, and FEF 25-75 in 96.77±29.88%. Abnormal lung functions were found in 15.7%. Small airway disease (FEF 25-75 <65%) was 7.1%. Restrictive defect (FVC<80%) was 6.3%. Airway obstruction (FEV 1 /FVC<70%) was 2.4%. There was no BDR. Compared to people with normal lung functions, the abnormal lung function group was older (48.00±8.68 years vs 42.96±11.61 years, P=0.036), and had a higher proportion of breathlessness (20.0% vs 3.7%, P=0.021). Conclusions: Abnormal pulmonary functions, especially small airway disease , were relatively common in rural residents in a polluted air area in northern Thailand. These abnormal pulmonary functions were associated with more respiratory symptoms.

Comprehensive review of the annual haze episode in Northern Thailand

“…More recent assessments have observed a potential decrease in morbidity in the last few years (Chi Htwe et al, 2023) and have concluded that 33.1% of individuals report a respiratory symptom when the PM2.5 average value is 35 μg/m 3 (2 to 128 μg/m 3 ). These individuals described their symptoms as 14.2% of runny nose; 10.2% of nasal obstruction; 9.4% of cough; 7.9% of sputum production 7.1% of allergic rhinitis and 6.3% of breathlessness and an additional 15.7% of abnormal lung function reported (Ruchiwit et al, 2022). Another earlier study found that the 5 main symptoms were 34.8% of blocked nose, 33.7% of tiredness, 32.9% of body itch, 30.7% of burning & itchy eyes and 28.7% of running nose (Wiwatanadate, 2014).…”