Effect of Seasonal Alterations of Air Quality Including Asian Sand Dust on Health‐related Quality of Life and Respiratory Symptoms in Korea

Abstract

BackgroundThe burden of chronic obstructive pulmonary disease (COPD) is expected to increase in the coming decades. In Korea, air pollution, which has been suggested to correlate with COPD, is a growing concern because of transboundary air pollution and Asian Sand Dust (ASD) event.MethodsSubjects were 165 patients who visited the hospital in Hwaseong city (25 mile south of Seoul) in February from 2013 to 2015. Patients with COPD aged 40 – 79 years were classified as “Patients”, whereas hospital patients without any respiratory diseases were recruited as “Controls”. These subjects filled out the questionnaire, which is a self‐completed booklet containing questions on the age, sex, smoking history, occupation, respiratory symptoms, and questionnaires on the subjects' health‐related quality of life (HR‐QoL) in February, May and July. Generalized estimation equation analysis was carried out to predict the factors affecting the patients' health and HR‐QoL. Odds ratios were adjusted for age, sex, body mass index, smoking status, COPD severity, air cleaner, time spent outdoors, temperature, humidity and concentrations of air pollutants (PM10, PM2.5, NO2, ozone or carbon monoxide), rate of the day exceeding Korean National Ambient Air Quality Standard (NAAQS) or ASD event. Air quality data were obtained from regional monitoring station.ResultMost of the aspects of HR‐QoL and respiratory symptoms were significantly worse in the COPD patients in each season. COPD severity was affected all aspects of HR‐QoL except for items regarding feelings, daily activities and change of health. Aside from COPD, physical fitness was affected significantly by rate of the day exceeding NAAQS of PM10, PM2.5 and NO2, and by ASD event. ASD event also worsened HR‐QoL regarding role limitation due to physical health problems. HR‐QoL regarding daily activities was worsened significantly by PM10 concentration and rate of the day exceeding NAAQS of PM10. Social function subscale was worsened by increasing concentration of PM2.5 and NO2. The effect of weather on cough was affected by PM10 and ozone concentrations regardless of COPD severity. PM2.5 concentration worsened wheezing especially in the COPD patients. The rate of the day exceeding NAAQS of any pollutants and ASD event did not affect any respiratory symptoms assessed in this study.ConclusionsPhysical aspects of HR‐QoL was susceptible to air pollution and some of these items or subscales were further exacerbated in association with COPD severity. This result suggests that HR‐QoL should be considered as adverse health effect of air pollution. With respect to the symptoms, coarse particles and gaseous pollutant affected cough regardless of COPD, and fine particulate matter worsened wheezing particularly in the COPD patients. Therefore, tailored intervention depending on the type of air pollution may be required to the prevention of adverse health effect of air pollution.Support or Funding InformationThis study was supported in part by Grants‐in‐Aid for Scientific Research (B) 20406001, 23406001 and (C) 26340053, and a “MEXT‐Supported Program for the Strategic Research Foundation at Private Universities” from the Ministry of Education, Culture, Sports, Science and Technology, Japan.