Ambient relative humidity-dependent obstructive sleep apnea severity in cold season: A case-control study

Kuan-Jen Bai; Wen-Te Liu; Yuan-Chien Lin; Yansu He; Yueh-Lun Lee; Dean Wu; Ta-Yuan Chang; Li-Te Chang; Chun-Yeh Lai; Cheng-Yu Tsai; Kian Fan Chung; Kin-Fai Ho; Kai-Jen Chuang; Hsiao-Chi Chuang

doi:10.1016/j.scitotenv.2022.160586

Ambient relative humidity-dependent obstructive sleep apnea severity in cold season: A case-control study

Sci Total Environ. 2023 Feb 25:861:160586. doi: 10.1016/j.scitotenv.2022.160586. Epub 2022 Nov 28.

Authors

Kuan-Jen Bai¹, Wen-Te Liu², Yuan-Chien Lin³, Yansu He⁴, Yueh-Lun Lee⁵, Dean Wu⁶, Ta-Yuan Chang⁷, Li-Te Chang⁸, Chun-Yeh Lai⁹, Cheng-Yu Tsai¹⁰, Kian Fan Chung¹¹, Kin-Fai Ho¹², Kai-Jen Chuang¹³, Hsiao-Chi Chuang¹⁴

Affiliations

¹ School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Pulmonary Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan. Electronic address: bkj@tmu.edu.tw.
² School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan; Sleep Center, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan; Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.
³ Department of Civil Engineering, National Central University, Taoyuan City, Taiwan. Electronic address: yclin@ncu.edu.tw.
⁴ Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: yansuhe@link.cuhk.edu.hk.
⁵ Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: yllee@tmu.edu.tw.
⁶ Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Neurology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan. Electronic address: d102095020@tmu.edu.tw.
⁷ Department of Occupational Safety and Health, College of Public Health, China Medical University, Taichung, Taiwan. Electronic address: tychang@mail.cmu.edu.tw.
⁸ Department of Environmental Engineering and Science, Feng Chia University, Taichung, Taiwan. Electronic address: ltechang@fcu.edu.tw.
⁹ Department of Civil Engineering, National Central University, Taoyuan City, Taiwan.
¹⁰ Department of Civil and Environmental Engineering, Imperial College London, London, UK.
¹¹ National Heart and Lung Institute, Imperial College London, London, UK. Electronic address: f.chung@imperial.ac.uk.
¹² Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Key Laboratory of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China. Electronic address: kfho@cuhk.edu.hk.
¹³ School of Public Health, College of Public Health, Taipei Medical University, Taipei, Taiwan; Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: kjc@tmu.edu.tw.
¹⁴ School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Cell Physiology and Molecular Image Research Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan. Electronic address: chuanghc@tmu.edu.tw.

PMID: 36455744
DOI: 10.1016/j.scitotenv.2022.160586

Abstract

Background: The objective of this study was to examine associations of daily averages and daily variations in ambient relative humidity (RH), temperature, and PM_2.5 on the obstructive sleep apnea (OSA) severity.

Methods: A case-control study was conducted to retrospectively recruit 8628 subjects in a sleep center between January 2015 and December 2021, including 1307 control (apnea-hypopnea index (AHI) < 5 events/h), 3661 mild-to-moderate OSA (AHI of 5-30 events/h), and 3597 severe OSA subjects (AHI > 30 events/h). A logistic regression was used to examine the odds ratio (OR) of outcome variables (daily mean or difference in RH, temperature, and PM_2.5 for 1, 7, and 30 days) with OSA severity (by the groups). Two-factor logistic regression models were conducted to examine the OR of RH with the daily mean or difference in temperature or PM_2.5 with OSA severity. An exposure-response relationship analysis was conducted to examine the outcome variables with OSA severity in all, cold and warm seasons.

Results: We observed associations of mean PM_2.5 and RH with respective increases of 0.04-0.08 and 0.01-0.03 events/h for the AHI in OSA patients. An increase in the daily difference of 1 % RH increased the AHI by 0.02-0.03 events/h in OSA patients. A daily PM_2.5 decrease of 1 μg/m³ reduced the AHI by 0.03 events/h, whereas a daily decrease in the RH of 1 % reduced the AHI by 0.03-0.04 events/h. The two-factor model confirmed the most robust associations of ambient RH with AHI in OSA patients. The exposure-response relationship in temperature and RH showed obviously seasonal patterns with OSA severity.

Conclusion: Short-term ambient variations in RH and PM_2.5 were associated with changes in the AHI in OSA patients, especially RH in cold season. Reducing exposure to high ambient RH and PM_2.5 levels may have protective effects on the AHI in OSA patients.

Keywords: AHI; Air pollution; PM(2.5); Sleep; Temperature.

MeSH terms

Case-Control Studies
Humans
Humidity
Particulate Matter
Retrospective Studies
Seasons
Sleep Apnea, Obstructive* / epidemiology

Substances

Particulate Matter