Disease and exposure variable characteristics in 20 studies.

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Forest plot of seasonal variation and IBD exacerbation of temperate climate studies (seven studies).

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Fig 2 -

Risk of acute exacerbation of IBD due to ambient temperature change in NHIS cohort for each temperature quartile (a. cold quartile [-19.4°C–4.3°C], b. cool quartile [4.3–13.7], c. warm quartile [13.7–21.3], d. hot quartile [21.3–33.5]). The risk is described via ORs (dot) with 95% CIs (bar) through single lags (0 to 6) and moving averages (0–1 to 0–6). ORs are estimated with adjustment for daily relative humidity, PM10, NO2, SO2, CO and O3, per 1 °C decrease in daily average temperature for a; per 1 °C increase in daily average temperature for b, c and d. *Abbreviations: IBD, inflammatory bowel disease; NHIS, National Health Insurance Service; OR, odds ratio; CI, confidence interval.</p

Fig 4 -

Risk of acute exacerbation of IBD due to ambient temperature change across temperature deciles in two large cohorts (a. NHIS cohort, b. UK Biobank cohort). The risk is described via ORs (dot) with 95% CIs (bar) when assuming no lag effect (lag 0). ORs are estimated with adjustment for daily relative humidity, PM10, NO2, SO2, CO and O3 in a; with no adjustment in b. The ambient temperature changes are considered per 1 °C decrease in daily average temperature for the first two deciles; per 1 °C increase in daily average temperature for the last eight deciles. *Abbreviations: IBD, inflammatory bowel disease; NHIS, National Health Insurance Service; OR, odds ratio; CI, confidence interval.</p