Standardized 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 Britain. RESEARCH DESIGN AND METHODS: Subjects studied were from rural and urban Cameroon or from Jamaica, or were Caribbean migrants, mainly Jamaican, living in Manchester, England. Sampling bases included a local census of adults aged 25-74 years in Cameroon, districts statistically representative in Jamaica, and population registers in Manchester. African-Caribbean ethnicity required three grandparents of this ethnicity. Diabetes was defined by the World Health Organization (WHO) 1985 criteria using a 75-g oral glucose tolerance test (2-h > or = 11.1 mmol/l or hypoglycemic treatment) and by the new American Diabetes Association criteria (fasting glucose > or = 7.0 mmol/l or hypoglycemic treatment). RESULTS: For men, mean BMIs were greatest in urban Cameroon and Manchester (25-27 kg/m2); in women, these were similarly high in urban Cameroon and Jamaica and highest in Manchester (27-28 kg/m2). The age-standardized diabetes prevalence using WHO criteria was 0.8 percent in rural Cameroon, 2.0 percent in urban Cameroon, 8.5 percent in Jamaica, and 14.6 percent in Manchester, with no difference between sexes (men: 1.1 percent, 1.0 percent, 6.5 percent, 15.3 percent, women: 0.5 percent, 2.8 percent, 10.6 percent, 14.0 percent), all tests for trend P < 0.001. Impaired glucose tolerance was more frequent in Jamaica. CONCLUSIONS: The transition in glucose intolerance from Cameroon to Jamaica and Britain suggests that environment determines diabetes prevalence in these populations of similar genetic origin.(Au)

Standardised comparison of glucose tolerance and diabetes prevalence in four African/African-Caribbean populations in Britain, Jamaica and Cameroon

To study factors promoting the emergence of diabetes in African-Caribbean (AfC) as the second largest ethnic minority in Britain and how these compare with genetically similar populations in Jamaica (origin of 80 percent AfC) and Cameroon, using the same protocol we carried out 75g glucose tolerance tests in representative community samples aged 25-74 years, by WHO criteria. As results were similar by gender, sexes are combined here. [See table] Diabetes prevalence (age-standardised) increased from Africa to the Caribbean to Europe and was highest in Manchester men. Body mass index showed a striking increase from rural to younger urban Cameroonians. Increasing NIDDM prevalence is paralleled across site by changes in nutritional and lifestyle factors, also measured using standardised methods. Even in Cameroon, prevalence approaches rates in whites in Europe.(AU)