Birth-cohort patterns indicate that the development of Crohn’s disease and multiple sclerosis (MS) is influenced by exposure to environmental risk factors during an early period of life, according to a recent study. These environmental risk factors may be similar or even identical in Crohn’s disease and MS. Researchers analyzed mortality data of Crohn’s disease and MS from the US, Canada, England, Italy, the Netherlands, and Switzerland during the past 60 years. Age–period–cohort (APC) analyses based on logit models served to disentangle the separate influences of age, period, and cohort effects on the overall time trends. They found:
- The long-term time trends of Crohn’s disease and MS have been shaped by strikingly similar birth-cohort patterns.
- In both diseases alike, mortality increased in all generations born prior to 1910.
- It peaked among generations born between 1910 and 1930 and then declined in all subsequent generations.
- Similar birth-cohort patterns of Crohn’s disease and MS were found in each country analyzed separately.
Sonnenberg A, Ajdacic-Gross V. Similar birth-cohort patterns in Crohn’s disease and multiple sclerosis. Mult Scler. 2018;24(2):140-149. doi:10.1177/1352458517691620.