PS-C30-7: THE ASSOCIATION BETWEEN INSULIN RESISTANCE AND DECLINE IN ORGAN FUNCTION IN NON-OBESE JAPANESE INDIVIDUALS

Abstract

Background: Obesity-induced insulin resistance is a critical metabolic abnormality involved in the decline in various organ functions, which likely contributes to the development of serious diseases, such as type 2 diabetes, hypertension, and cardiovascular disease. However, little information is available on the association between insulin resistance and organ function in non-obese people. The major purpose of this study was to investigate the relationship between insulin resistance (estimated by the homeostasis model assessment for insulin resistance, HOMA-IR) and selected indicators of organ-specific functions in non-obese individuals. Materials and Methods: We analyzed data obtained from non-obese (body mass index [BMI], 18.5 to < 25 kg/m2), non-diabetic 3546 Japanese individuals (2034 men and 1512 women) who received health checkups in 2018 at Keio University Hospital. Individuals were divided into quartiles according to their HOMA-IR values. Multiple regression analysis was performed to further investigate the relationship between HOMA-IR values and organ parameters after adjustment for covariates, such as age, gender, and BMI. Results: Those with HOMA-IR in the highest quartile had a higher incidence of metabolic syndrome, hypertension, stroke, and chronic kidney disease. There were significant stepwise (P < 0.05) increases in metabolic syndrome indicators (BMI, visceral adipose tissue area, triglyceride, uric acid), liver enzymes (AST, ALT, γGTP, ChE), systemic inflammatory markers (white blood cell count, CRP), systolic and diastolic blood pressure, and ocular pressure, from the first quartile to fourth quartile of HOMA-IR, whereas there were stepwise decreases in HDL-C and parameters of renal function (eGFR) and pulmonary function (forced expiratory volume, vital capacity). Multiple regression analyses revealed that HOMA-IR values were significantly (P < 0.05) associated with these parameters expect eGFR even after adjusting for covariates. Conclusion: Our results suggest that insulin resistance is associated with decline in the function of multiple organs in non-obese, non-diabetic Japanese individuals. Further studies are required to establish cause and effect in this relationship.