Total insulin output is low in type-2 diabetic Nigerians

ABSTRACT

Plasma insulin levels among type 2 diabetic patients are modulated by racial and ethnic factors. In contrast to the plethora of reported studies on plasma insulin levels among type 2 diabetic patients in technically advanced regions of the world, there is paucity of such information in Africa in general. To study insulin output among type 2 diabetic Nigerians. Forty type-2 diabetic and 36 healthy subjects underwent a standard oral glucose tolerance test [OGTT]. Fasting and post OGTT plasma insulin levels were measured using an ELISA technique. Integrated insulin responses were calculated using trapezoidal estimation to compute total insulin output. Student's t test was used to compare means; the level of statistical significance in each case was taken as p < 0.05. The age and sex distribution of diabetic patients and control subjects were similar [p >0.5]. Average duration of diabetes was 5.6 +/- 4.3 years [range 1 -20 years] Total insulin output was significantly lower among type 2 diabetic patients than in control subjects [360 +/- 82.1 microunits per ml and 745.1 +/- 109.0 micro-units per ml respectively P<0.00 1]. Type-2 diabetic patients in this study exhibit hypoinsulinaemia; this could be the explanation for the pattern of diabetic complications among type 2 diabetic Nigerians observed in previous studies