ArticleBMC public health2013
Can temperature explain the latitudinal gradient of ulcerative colitis? Cohort of Norway.
Article in BMC public health, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
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Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it, 24 citations in OpenAlex.
- Prevalence of autoimmune diseases is strongly associated with average annual temperatures: systematic review and linear regression analysis.BMC rheumatology · 2025Pooled it
- The exposome and inflammatory bowel disease: a framework for primary and primordial prevention.Nature reviews. Gastroenterology & hepatology · 2026Review
- The Inflammatory Bowel Disease in South-Eastern Norway study: three decades of advancements in clinical understanding and scientific partnerships.Therapeutic advances in gastroenterology · 2026Review
- High-Fat/High-Sugar Diet and High-Temperature/High-Humidity Exposure Aggravates Ulcerative Colitis in an Experimental Mouse Model.Current issues in molecular biology · 2025Article
- Article
- Prevention of ulcerative colitis by Huangqin decoction: reducing the intestinal epithelial cell apoptosis rate through the IFN-γ/JAK/ETS signalling pathway.Pharmaceutical biology · 2022Article
- Incidence and Prevalence of Inflammatory Bowel Disease across Asia.Yonsei medical journal · 2021Review
- Long-term effects of latitude, ambient temperature, and ultraviolet radiation on the incidence of multiple sclerosis in two cohorts of US women.Environmental epidemiology (Philadelphia, Pa.) · 2020Article
- Relationship(s) between obesity and inflammatory bowel diseases: possible intertwined pathogenic mechanisms.Clinical journal of gastroenterology · 2020Review
- Changing Patterns of Relationships Between Geographic Markers and IBD: Possible Intrusion of Obesity.Crohn's & colitis 360 · 2020Article
- Epidemiology and hospital resources use in the treatment of ulcerative colitis at gastroenterology units in Spain (EPICURE study).Drugs in context · 2018Article
- Influence of environmental factors on the onset and course of inflammatory bowel disease.World journal of gastroenterology · 2016Review
- Latitude, sunshine, and human lactase phenotype distributions may contribute to geographic patterns of modern disease: the inflammatory bowel disease model.Clinical epidemiology · 2014Article
Corrections and comments
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Authors and funding
3 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundIncidence and prevalence of ulcerative colitis follow a north-south (latitudinal) gradient and increases northwards at the northern hemisphere or southwards at the southern hemisphere. The disease has increased during the last decades. The temporal trend has been explained by the hygiene hypothesis, but few parallel explanations exist for the spatial variability. Many factors are linked to latitude such as climate. Our purpose was to investigate the association between variables governing the climate and prospectively identified patients.
methodsIn this study, we used a subset of the population-based Cohort of Norway (n = 80412) where 370 prevalent cases of ulcerative colitis were identified through self-reported medication. The meteorological and climatic variables temperature, precipitation, and altitude were recorded from weather stations of the Norwegian Meteorological Institute. Summer temperature was used to capture environmental temperature.
resultsSummer temperature was significantly related to the prevalence of ulcerative colitis. For each one-degree increase in temperature the odds for ulcerative colitis decreased with about 9% (95% CI: 3%-15%). None of the other climatic factors were significantly associated to the risk of ulcerative colitis. Contextual variables did not change the association to the prevalence of ulcerative colitis.
conclusionsThe present results show that the prevalence of ulcerative colitis is associated to summer temperature. Our speculation is that summer temperature works as an instrumental variable for the effect of microbial species richness on the development of ulcerative colitis. Environmental temperature is one of the main forces governing microbial species richness and the microbial composition of the commensal gut flora is known to be an important part in the process leading to ulcerative colitis.
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