Nitrogen dioxide and hospital length of stay and cost for systemic lupus erythematosus in Hunan, China

Peng Chen; Jundong Huang; Shenxin Li; Yan Tang; Yi Xiao; Bin Zou; Xiang Chen; Ji Li; Zhixiang Zhao; Minxue Shen

doi:10.1016/j.scitotenv.2022.159013

Nitrogen dioxide and hospital length of stay and cost for systemic lupus erythematosus in Hunan, China

Sci Total Environ. 2023 Jan 15;856(Pt 1):159013. doi: 10.1016/j.scitotenv.2022.159013. Epub 2022 Sep 23.

Authors

Peng Chen¹, Jundong Huang¹, Shenxin Li², Yan Tang¹, Yi Xiao¹, Bin Zou², Xiang Chen³, Ji Li⁴, Zhixiang Zhao⁴, Minxue Shen⁵

Affiliations

¹ Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.
² Department of Surveying and Remote Sensing Science, School of Geosciences and Info-physics, Central South University, Changsha, China.
³ Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China; Hunan Engineering Research Center of Skin Health and Disease, Xiangya Hospital, Central South University, Changsha, China.
⁴ Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China; Hunan Key Laboratory of Aging Biology, Xiangya Hospital, Central South University, Changsha, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.
⁵ Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China; Department of Social Medicine and Health Management, Xiangya School of Public Health, Central South University, Changsha, China. Electronic address: shenmx1988@csu.edu.cn.

PMID: 36162573
DOI: 10.1016/j.scitotenv.2022.159013

Abstract

Background: Evidence of both epidemiological and clinical studies exploring the impact of nitrogen dioxide (NO₂) on the systemic lupus erythematosus (SLE) disease activity have been contradictory.

Objectives: To evaluate the association between short-term NO₂ exposure and length of hospital stay (LOS) and hospital cost of SLE and estimate the burden of disease attributable to NO₂ exposure.

Methods: We collected health data of SLE inpatients who were hospitalized at secondary and tertiary hospitals in Hunan province of China during 2017-2019. Daily ambient concentrations of air pollutants (O₃, CO, NO₂, SO₂, PM_2.5 and PM₁₀) and other environmental factors were obtained from public repositories by linking to individual addresses and date of hospitalization. Mixed effect models were employed to assess the associations between LOS and hospital cost for SLE inpatients and NO₂ exposures during the previous 1 to 21 days (lag₁-lag₂₁) before hospitalization. We further estimated excess LOS and hospital cost attributable to NO₂ exposure according to China's and World Health Organization's air quality guideline (AQG) respectively.

Results: A total of 11,447 records from 221 hospitals were finally included in our study. After full adjustments, 1 μg/m³ increment of NO₂ was significantly associated with 0.038 day increase in LOS (95%CI: 0.0159-0.0601, P = 0.0008) and 0.0384 thousand yuan increase in hospital cost (95%CI: 0.0017-0.0679, P = 0.0395) with a lagged effect of 7 days prior to admission. Based on the adjusted effects of lag₇, controlling for short-term NO₂ exposure according to AQG could avoid up to 1.47 thousand days of hospitalization and 1.35 million yuan of cost for SLE in Hunan province during 2017 to 2019.

Conclusions: Excess LOS and substantial economic burden among SLE inpatients attributable to NO₂ could be avoid if policies were implemented to reduce the exposure.

Keywords: China; Length of hospital stay; Nitrogen dioxide; Systemic lupus erythematosus; Time-series study.

MeSH terms

Air Pollutants* / analysis
Air Pollution* / analysis
China / epidemiology
Hospitals
Humans
Length of Stay
Lupus Erythematosus, Systemic* / epidemiology
Nitrogen Dioxide / analysis
Particulate Matter / analysis

Substances

Nitrogen Dioxide
Air Pollutants
Particulate Matter