Association between exposure to air pollutants and the risk of inflammatory bowel diseases visits

Abstract

BackgroundThe topic of in ammatory bowel disease (IBD) has attracted more and more attentions. Accumulating evidence suggests that exposure to air pollutants is associated with IBD, yet the results are inconsistent and study about daily exposure is few. This study evaluated the association between daily air pollution and IBD in Hefei, China. MethodsDaily IBD admission data were obtained from two hospitals in Hefei from January 1, 2019 to December 31, 2019. Daily concentrations of major air pollutants were provided by the Hefei Environmental Protection Bureau. Meteorological data were collected from China Meteorological Data Network.Distributed lag nonlinear model (DLNM) considering both the lag effects of exposure factors and nonlinear relationship of exposure-reaction was used to assess the effect of daily air pollutants exposure on IBD admission. ResultsDuring the study period, totally 886 cases of IBD were recruited, including 313 cases of ulcerative colitis (UC) and 573 cases of Crohn's disease (CD). The ndings showed PM 2.5 , O 3 and CO exposure signi cantly increased the risk of IBD. Mean concentrations of PM 2.5 , O 3 and CO in Hefei were 43.85ug/m³, 100.78ug/m³, and 0.76mg/m³, respectively. Each increase of 10mg/m³ in PM 2.5 / O 3 and 0.1mg/m³ in CO increased the risk of IBD. The strongest effects of these three pollutants on IBD were observed in lag2-lag3 (RR = 1.037, 95% CI: 1.005-1.070%), lag3 (RR = 1.020, 95% CI: 1.002-1.038%) and lag2 (RR = 1.036, 95% CI: 1.003-1.071%), respectively. In warm seasons, PM 2.5 , O 3 and CO had a stronger effect increased the risk of IBD, which were observed in lag2 (RR = 1.

Treatment patterns of anti‐tumour necrosis factor‐alpha and prognosis of paediatric and adult‐onset inflammatory bowel disease in Korea: a nationwide population‐based study

“…2 To date, the change in the trend of IBD prevalence in paediatric patients has been reported in observational studies; however, it has not been clearly demonstrated for Asian countries, which are facing issues such as consumption of processed meat, pollution, extreme heat and climate changes. [3][4][5] In South Korea, equitable access to healthcare is uniformly provided across the nation through its characteristic universal health coverage. 6 The contextual background of Korea provides a unique opportunity to observe trends in IBD epidemiology, including treatment patterns and prognostic differences at a population level.…”

“…The aetiology of IBD is multifactorial and includes genetic and environmental factors 2 . To date, the change in the trend of IBD prevalence in paediatric patients has been reported in observational studies; however, it has not been clearly demonstrated for Asian countries, which are facing issues such as consumption of processed meat, pollution, extreme heat and climate changes 3–5 …”

Effects of temperature, weather, seasons, atmosphere, and climate on the exacerbation of inflammatory bowel diseases: A systematic review and meta-analysis

“…There was a low level of heterogeneity between the studies in both overall and subgroup analyses. Although the meta-analysis of three studies on air pollution was not performed [ 27 , 51 , 52 ], all three of the studies reported a significant positive correlation between air pollutants and exacerbation of IBD.…”

“…Furthermore, only 6 out of 20 studies reported information on the duration of IBD morbidity, location of lesions, or medications administered [ 20 – 24 , 50 ]. Moreover, 7 out of 20 studies did not report the number of patients who experienced IBD exacerbations [ 18 , 20 , 26 , 27 , 49 , 51 , 52 ], and 6 of the 11 studies reported different numbers of patients and cases of exacerbations [ 19 , 21 , 22 , 25 , 48 , 50 ]. The abovementioned factors might have resulted in the underestimation or overestimation of the pooled estimate results of the meta-analysis.…”

“…In addition, the method used for defining IBD exacerbation varied across studies; specifically, 7 out of 20 studies did not use a standard definition (i.e., cutoff for IBD activity measurements or inclusion criteria) ( S4 Table ). Among the included studies, there was one study in which the outpatient visit was defined as exacerbation [ 52 ]. There is a possibility that the outpatient visit may be different from the actual exacerbation time, so if other indicators such as disease activity are not considered together, the risk of misclassification may increase, and interpretation should be careful.…”