Diverticular disease and migration – the influence of acculturation to a Western lifestyle on diverticular disease

BACKGROUND: Diverticular disease of the colon is more common in the Western world, compared with non-Western countries. AIM: To investigate the risk of diverticular disease in immigrants of diverse ethnicity and in different phases of acculturation. METHODS: Socio-demographic indicators and the risk of diverticular disease were investigated. The study population was a prospectively followed national cohort of 4 million residents born between 1925 and 1965. Risk ratios (RRs) of hospital admissions and deaths because of diverticular disease and acute diverticulitis from 1991 through 2000 were calculated. RESULTS: The risk of hospital admission because of diverticular disease, after adjustment for age, sex and socio-economic indicators, was lower in non-Western immigrants (RRs = 0.5-0.7) compared with natives and the risk increased with time after the settlement. Women of all origins had a higher risk compared with men (RR = 1.5). This sex-difference increased with age (P < 0.001). Socio-economic status, residency or housing situation were not risk factors. CONCLUSION: This population-based study found that immigrants from non-Westernized countries had lower relative risks for hospitalization because of diverticular disease than natives, but the risk increased during a relatively short period of time after settlement. Diverticular disease of the colon appears to be an acquired disorder and acculturation to a Western lifestyle has an impact on the risk.