Plasma insulin response to oral glucose tolerance test in type-2 Nigerian diabetics.

摘要

OBJECTIVE: To study the plasma insulin pattern in type 2 diabetic Nigerians both in the fasting state and in response to a standard oral glucose tolerance test. DESIGN: A cross sectional study. SETTING: Diabetic clinic, Ahmadu Bello University Teaching Hospital, Zaria Nigeria. SUBJECTS: Forty type 2 diabetic patients and thirty six healthy age and sex matched control subjects was undertaken. INTERVENTIONS: Eligible patients and control subjects underwent a standard oral glucose tolerance test (OGTT). Plasma levels of glucose and insulin levels determined by a glucose oxidase method and ELISA techniques respectively. Student's t-test was used to compare continuous variables, Chi-square test for categorical variable and Pearson's correlation coefficient to define correlation between variables. The level of statistical significance in each case was taken as P < 0.05. RESULTS: Type 2 diabetic patients demonstrated significantly lower fasting plasma insulin levels, when compared to control subjects (4.20+/-1.78 micro- units/ml vs 5.72+/-2.16 micro - units/ml respectively p<0.05). Similarly, plasma insulin levels following oral glucose challenge were significantly lower in the type 2 diabetic population. CONCLUSION: Type 2 diabetic patients in this study demonstrate both fasting post OGTT hypoinsulinaemia. These findings are discussed in the light of the available knowledge on the aetiopathogenesis of type-2 diabetes mellitus in Africans.