Standardised comparison of glucose intolerance in West African-origin populations of rural and urban Cameroon, Jamaica, and Caribbean migrants to Britain

OBJECTIVE - To compare the prevalence of glucose intolerance in genetically similar African-origin populations within Cameroon and from Jamaica and Br itain. RESEARCH DESIGN AND METHODS - Subjects studied were from rural and urban Ca meroon or from Jamaica, or were Caribbean migrants, mainly Jamaican, living in Manchester, England. Sampling bases included a local census of adults a ged 25-74 years in Cameroon, districts statistically representative in Jama ica, and population registers in Manchester. African-Caribbean ethnicity re quired three grandparents of this ethnicity: Diabetes was defined by the Wo rld Health Organization (WHO) 1985 criteria using a 75-g oral glucose toler ance test (2-h greater than or equal to 11.1 mmol/l or hypoglycemic treatme nt) and by the new American Diabetes Association criteria (fasting glucose greater than or equal to 7.0 mmol/l or hypoglycemic treatment). RESULTS - For men, mean BMIs were greatest in urban Cameroon and Manchester (25-27 kg/m(2)); in women, these were similarly high in urban Cameroon and Jamaica and highest in Manchester (27-28 kg/m(2)). The age-standardized di abetes prevalence using WHO criteria was 0.8% in rural Cameroon, 2.0% in ur ban Cameroon, 8.5% in Jamaica, and 14.6% in Manchester, with no difference between sexes (men: 1.1%, 1.0%, 6.5%, 15.3%, women: 0.5%, 2.8%, 10.6%, 14.0 %). all tests for trend P < 0.001, Impaired glucose tolerance was more freq uent in Jamaica. CONCLUSIONS - The transition in glucose intolerance from Cameroon to Jamaic a and Britain suggests that environment determines diabetes prevalence in t hese populations of similar genetic origin.