African immigrants with type 2 diabetes present with three physiologic subtypes: implications for screening, diagnosis and treatment

INTRODUCTION: As type 2 diabetes (T2D) prevalence increases in the USA and Africa, factors from both regions affect African immigrants. OBJECTIVE: T2D in African immigrants was characterized by examining: (a) insulin deficiency and insulin resistance; (b) phenotypic presentation; (c) sociodemographic factors. METHODS: ), weight gain information was collected, BMI and waist circumference (WC) measured and OGTT performed. Insulin resistance was defined by the lowest quartile of the Matsuda Index (≤2.80); insulin secretion by the Insulin Secretion Index (ISI). Insulin deficiency was defined as less than the maximum ISI in participants with T2D without IR (0.430). WC thresholds defined central obesity (men: WC ≥94 cm; women ≥80 cm). RESULTS: Normal glucose tolerance, pre-diabetes and T2D occurred in 61%, 32% and 7%, respectively. Three subtypes of T2D were identified: insulin-deficient-T2D (ID-T2D) in 45%, insulin-resistant-T2D (IR-T2D) in 30%, insulin-deficient+insulin-resistant (ID+IR-T2D) in 25%. ID+IR-T2D had the highest glucose concentrations (all p