Patterns of insulin resistance in the general population of southeast Spain

Abstract 

The aim of this study was to evaluate patterns of insulin resistance in the general population. The study was cross sectional. Clinical, anthropometric, and lipid measurements were made in 1226 persons aged 18–65 years. An oral glucose tolerance test (OGTT) was performed in 1020 subjects, with insulin levels determined at baseline and after 2h. The homeostasis model assessment insulin resistance index (HOMA IR) and HOMA β-cell function were calculated. Compared with subjects with normal glucose tolerance, the groups with abnormal OGTT had different baseline insulinemia, 2h post OGTT insulinemia, HOMA IR and HOMA β-cell indices. Serum insulin levels at baseline and 2h after OGTT showed a characteristic pattern for each category of glucose tolerance, resulting from the different insulin responses. In the subjects with normal glucose tolerance, the pattern of the relationships between both types of serum insulin levels was exactly the same, so that it was possible to determine risk groups according to the ratio of baseline serum insulin/2h insulin. HOMA IR and HOMA β-cell were significantly associated with the risk of impaired fasting glucose, previously unknown diabetes mellitus, and known diabetes mellitus. These results support the rationale for introducing preventive measures against insulin resistance in the general population.

Keywords:  Insulin resistance, HOMA, Impaired fasting glucose, Impaired glucose tolerance, Diabetes mellitus