Development of a protocol for estimating blood glucose range index by CGM mathematical analysis

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K16341
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 54040:Metabolism and endocrinology-related
• Research Institution: Kobe University
• Principal Investigator: Matsuoka Atsuko 神戸大学, 医学研究科, 医学研究員 (80879966)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: CGM / time in range / 血糖変動

Outline of Final Research Achievements

We examined the relationship between TBR and TIR, and HbA1c and CV, and found that the combination of HbA1c and CV changed TBR and TIR, using CGM data of 300 patients with type 2 diabetes mellitus taking oral SU. In addition, CGM data and clinical data of subjects were examined using the gamlss package in R, and it was clarified that gamma, lognormal, and inverse Gaussian models fit the blood glucose distribution of actual patients. We show that TBR can be calculated as a cumulative distribution function at 70 mg/dL and that estimated TBR can be expressed as a function of mean blood glucose and CV. Through analysis of CGM data applying these mathematical models, we clarified the relationship between CGM indices and HbA1c.

Free Research Field

糖尿病内分泌内科

Academic Significance and Societal Importance of the Research Achievements

近年、持続血糖モニタリング(continuous glucose monitoring; CGM)の普及により低血糖や血糖変動性の評価が可能となり、より安全な治療を目指すことが可能となった。しかし常時CGMを行える環境ではない患者も多い。本研究では国際的コンセンサスで目標値とされる70-180mg/dlの血糖域;TIR (Time In Range)及び低血糖域TBR (Time Below Range)が血糖と血糖変動性の関数で表せることを明らかにした。すなわち、一度得られたCGM指標と日常診療の検査データを用いて、頻回にCGMを実施せずとも安全かつ効果的な治療を目指せるようになった。