Aims/Background: To prevent diabetic complications, strict glucose control and frequent monitoring of blood glucose levels with invasive methods are necessary. We considered monitoring of diabetes-related biomarkers in tears may be the possible methods for diabetes monitoring methods. Many studies about tear glucose levels have been reported and tear glucose levels correlate with blood glucose levels. This time, we focused on glycoalbumin (GA) levels, which reflect an average of blood glucose levels over the preceding 2 weeks, and studied the correlation between GA levels in blood and tears.
Methods: We recruited 100 diabetic subjects and collected blood and tear samples. GA levels in blood were measured by an enzymatic method, and GA levels in tears were measured by Liquid Chromatography/Mass Spectrometry (LC-MS/MS).
Results: The GA levels in tears of 99 out of 100 samples were appropriately measured by LC-MS/MS. GA levels in blood and tears were significantly correlated (P < 0.001). Multiple regression analysis revealed that this correlation was maintained even after adjustment for age, gender, nephropathy stage, and obesity (P < 0.001).
Conclusions: GA in tears was the first measured diabetes-related biomarker. GA levels in tears were strongly correlated with those in blood, considering various factors. As GA value is a ratio, GA levels in tears were not thought to be influenced by dilution or concentration of tears and showed strong correlation with those in blood. From the above, GA in tears could be a diabetes-related biomarker that can be measured noninvasively. In the future, we plan to optimize measurement conditions, develop measurement equipment and verify the effectiveness and usefulness of this diabetes monitoring method.
M. Aihara: None. N. Kubota: None. T. Kadowaki: Research Support; Self; Astellas Pharma Inc., Daiichi Sankyo, Mitsubishi Tanabe Pharma Corporation, MSD Corporation, Novartis Pharma K.K., Novo Nordisk Pharma Ltd., Ono Pharmaceutical Co., Ltd., Sanofi, Sumitomo Dainippon Pharma Co., Ltd., Takeda Pharmaceutical Company Limited. Speaker’s Bureau; Self; Abbott, Astellas Pharma Inc., AstraZeneca K.K., Boehringer Ingelheim Pharmaceuticals, Inc., Cosmic Corporation, Daiichi Sankyo, Eli Lilly Japan K.K., FUJIFILM, Kowa Company, Ltd., Kyowa Hakko Kirin Co., Ltd., Medscape Education, Medtronic, Mitsubishi Tanabe Pharma Corporation, MSD Corporation, NIPRO Medical Corporation, Novartis Pharma K.K., Novo Nordisk Pharma Ltd., Ono Pharmaceutical Co., Ltd., Sanofi, Sanwa Kagaku Kenkyusho, Sumitomo Dainippon Pharma Co., Ltd., Taisho Pharmaceutical Co., Ltd., Takeda Pharmaceutical Company Limited, Terumo Medical Corporation. Other Relationship; Self; Asahi Mutual Life Insurance.