Regional Variations of Insulin Secretion and Insulin Sensitivity in Japanese Participants With Normal Glucose Tolerance

Abstract

Purpose: Regional differences in dietary patterns in Asian countries might affect the balance of insulin response and sensitivity. However, this notion is yet to be validated. To clarify the regional differences in the insulin response and sensitivity and their relationship to nutrients, we compared the insulin secretory response during an oral glucose tolerance test in Japanese participants.Methods: This observational retrospective cohort study analyzed the data from participants with normal glucose tolerance (NGT) from four distinct areas of Japan with regard to the food environment: Fukushima, Nagano, Tokushima, and Okinawa based on data available in the Japanese National Health Insurance database.Results: Although the glucose levels were comparable among the four regions, the insulin responses were significantly different among the regions. This difference was observed even within the same BMI category. The plot between the insulin sensitivity index (Matsuda index) and insulinAUC/glucoseAUC or the insulinogenic index showed hyperbolic relationships with variations in regions. The indices of insulin secretion correlated positively with fat intake and negatively with the intake of fish, carbohydrate calories, and dietary fiber.Conclusions: We found that significant regional differences in insulin response and insulin sensitivity in Japanese participants and that nutritional factors may be linked to these differences independently of body size/adiposity. Insulin response and insulin sensitivity can vary among adult individuals, even within the same race and the same country, and are likely affected by environmental/lifestyle factors as well as genetic traits.

Differences in imeglimin response in subgroups of patients with type 2 diabetes stratified by data‐driven cluster analysis: A post‐hoc analysis of imeglimin clinical trial data

“…Furthermore, it should be noted that a cluster‐based subgroup analysis of a retrospective cohort study in Japanese patients with diabetes also identified five distinct subgroups of adult‐onset diabetes similar to Ahlquist et al, 4 although severe autoimmune diabetes (SAID), severe insulin‐deficient diabetes (SIDD) and severe insulin‐resistant diabetes (SIRD) subgroups were less frequent 18 . It has been previously reported that East Asians, including Japanese people, have lower insulin secretory capacity and insulin resistance than Caucasians 19,20 . This may partly explain the differences in frequency of the SAID, SIDD and SIRD subgroups observed between Japanese and Caucasians.…”

“…18 It has been previously reported that East Asians, including Japanese people, have lower insulin secretory capacity and insulin resistance than Caucasians. 19,20 This may partly explain the differences in frequency of the SAID, SIDD and SIRD subgroups observed between Japanese and Caucasians. HOMA2-IR and age at diagnosis were also significantly lower in the SIRD subgroup compared with Caucasians.…”