The Incidence and Prevalence of Inflammatory Bowel Disease Continues to Increase in the Faroe Islands - A Cohort Study from 1960 to 2020.

BACKGROUND AND AIMS: The highest reported incidence rate of inflammatory bowel disease [IBD], and especially of ulcerative colitis [UC], is found in the Faroe Islands. This study aimed to assess the incidence rate and temporal trends in prevalence over six decades. METHODS: All incident and prevalent patients diagnosed with IBD between 1960 and 2020 from the nationwide and population-based Faroese IBD cohort were included in this study. All patients fulfilled the Copenhagen Diagnostic Criteria. RESULTS: Overall, 873 individuals were diagnosed with IBD during the study period, 559 [64%] with UC, 151 [17%] with Crohn's disease, and 163 [19%] with IBD unclassified. A total of 59 patients had paediatric-onset IBD. The incidence of IBD continued to increase throughout the study period, as the age-standardized incidence rate started at 8 per 100 000 person-years [py] [European Standard Population, ESP] in 1960-79 and reached 70 by 2010-20. In 2021, the age-standardized period prevalence was 1414 per 100 000 persons. The IBD incidence was unevenly distributed among the islands with Sandoy having the highest rate of 106 per 100 000 py in 2010-2020. CONCLUSIONS: The incidence of IBD continues to increase in the Faroe Islands, mainly driven by UC. The incidence shows an uneven geographical distribution, which suggests an adverse interaction between unknown environmental factors and genetic traits. The prevalence in 2021 corresponded to 1.3% of the Faroese population. Environmental risk factors are suspected to impact this homogeneous high-risk population; however, the reason for this is unclear.

Temporal trends in cause-specific mortality in a rural-provincial area of Denmark, Lolland-Falster, 1970-2018.

AIM: In Denmark, rural-provincial Lolland-Falster currently has the highest mortality, caused mainly by the high mortality of in-migrating people. To identify possible preventive measures to combat this excess mortality insight into the underlying diseases is needed. METHODS: We used data from Danish registers to calculate cause-specific mortality for 1970-1979, 1980-1989, 1990-1999, 2000-2009 and 2010-2018 divided into cancer, cardiovascular diseases, respiratory diseases, external causes and other causes (all remaining causes). We calculated age-standardised mortality rates for Lolland-Falster and the rest of Denmark: mortality rate ratios and excess number of deaths per 100,000 person-years for Lolland-Falster distinguishing between long-term residents (10+ years) and in-migrants. RESULTS: In 1970-1979, the age-standardised mortality rates for Lolland-Falster resembled those for rest of Denmark. Over time, age-standardised mortality rates for cardiovascular diseases decreased but more so for the rest of Denmark than for Lolland-Falster. Age-standardised mortality rates for other diseases increased but more so for Lolland-Falster than for the rest of Denmark. The excess mortality in Lolland-Falster derived in particular from in-migrants: in 2010-2018 the mortality rate ratios for this population reached 2.29 (95% confidence interval 1.96-2.69) for external causes and 2.12 (95% confidence interval 1.97-2.29) for other diseases. In-migrants had in total 411 excess deaths per 100,000 person-years. Of these 27% came from tobacco smoking-related causes of death. However, another 25% came from ill-defined, unspecified and a broad range of other, minor causes of deaths. CONCLUSIONS: The excess mortality of in-migrants to Lolland-Falster was attributable to all main causes of deaths, which stresses the complexity in combatting geographical disparities in mortality.