Homeostatic Model Assessment of Insulin Activity and Iron Profile among Regular Blood Donors at a Tertiary Health Centre, South-West Nigeria.

CONTEXT

Iron overload has been established to play a role in the etiopathogenesis of Type 2 diabetes mellitus (DM) as evidenced by its high prevalence among patients with hemochromatosis and transfusion-dependent diseases. This is as a result of iron redox reaction which generates free radicals that cause peroxidation of lipid-rich pancreas, leading to reduced insulin sensitivity.

AIMS

This study therefore evaluated the impact of regular blood donation, an effective method of reducing iron load, on β-islet cell functions and level of glycemic control among regular whole blood donors.

SETTINGS AND DESIGN

This is a cross-sectional, analytical study.

SUBJECTS AND METHODS

Forty-two consenting regular blood donors who had donated whole blood at least twice and not more than thrice in the last 1 year were selected as cases, while 42 age-matched individuals who have never donated blood previously were selected as controls. Samples were obtained and analyzed for fasting plasma glucose, fasting plasma insulin, serum ferritin, transferrin receptor, total iron-binding capacity (TIBC), and serum iron, while Homeostatic Model Assessment (HOMA) of insulin resistance (IR) and beta sensitivity, HOMA-IR, and HOMA-β-cell function (HOMA-β%) were calculated for both groups.

STATISTICAL ANALYSIS USED

Statistical analysis was done using Microsoft Excel package and the Statistical Package for the Social Sciences (SPSS) version 20.0 (SPSS Inc., Chicago, IL, USA).

RESULTS

Iron studies among regular blood donors and nondonors revealed lower serum iron (37.2 ± 7.3 vs. 41.1 ± 7.9 μmol/L, = 0.180) and lower serum ferritin levels (30.2 ± 26.1 vs. 42.9 ± 38.5 ng/mL, = 0.117), which were not statistically significant, while there were higher serum transferrin receptor (155.5 ± 22.6 vs. 112.8 ± 43.4 ng/mL, < 0.001) and higher serum TIBC (42.3 ± 6.4 vs. 37.8 ± 7.4 μmol/L, < 0.05), among cases than controls. The mean HOMA-IR and HOMA-β% were also significantly better among donors than nondonors.

CONCLUSIONS

Regular blood donation may protect the body from the toxic effects of excessive iron store, which includes improved insulin sensitivity and glycemic control.