Characteristics of individuals who developed type 2 diabetes from prediabetes despite undergoing interventions, and evaluation of the performance of urinary myo-inositol as a risk factor for developing diabetes.

AIMS/INTRODUCTION: The aim of this study was to clarify the characteristics of individuals with prediabetes who developed type 2 diabetes despite undergoing interventions, and to evaluate the performance of urinary myo-inositol (UMI) as a noninvasive indicator for the risk of developing diabetes. MATERIALS AND METHODS: A total of 51 individuals with prediabetes who underwent a 75-g oral glucose tolerance test, ΔUMI (the difference in the UMI : creatinine ratio between before and 120 min after 75-g glucose loading), fasting plasma glucose, insulin, hemoglobin A1c, noninvasive testing (age, body mass index, blood pressure) and general blood tests were measured at baseline, and underwent dietary/exercise guidance for 8 years were studied. RESULTS: A total of 31 participants developed diabetes in 8 years. At baseline, the group that developed diabetes was characterized by high ΔUMI, hemoglobin A1c, fasting plasma glucose and low high-density lipoprotein cholesterol, and insulinogenic index (I.I.). I.I and ΔUMI showed a higher correlation than fasting plasma glucose and hemoglobin A1c. Regarding diabetes onset within 8 years, Cox regression analysis of diabetes onset showed the baseline ΔUMI is an independent predictor, adjusted for the result of not only noninvasive markers, but also that of noninvasive and general blood markers. The log-rank test showed that all glycemic indicators were significantly associated with diabetes onset. CONCLUSION: Participants who developed type 2 diabetes from prediabetes despite undergoing interventions were characterized by high glycemic control markers and low I.I. As noninvasive measurement of ΔUMI is associated with I.I. and diabetes onset, it could be a useful indicator for identifying individuals with a high risk of diabetes onset.

Simple and non-invasive screening method for diabetes based on myoinositol levels in urine samples collected at home.

OBJECTIVE: To establish a simple screening method for diabetes based on myoinositol (MI) in urine samples collected at home. RESEARCH DESIGN AND METHODS: Initially, we evaluated the stability of urinary MI (UMI) at room temperature (RT; 25°C) and 37°C in 10 outpatients with type 2 diabetes. We then enrolled 115 volunteers without a current or history of diabetes. In all subjects, glucose intolerance was diagnosed by 75 g oral glucose tolerance test (75gOGTT). To assess the association between UMI or urine glucose (UG) and plasma glucose (PG), urine samples were also collected at 0 and 2 hours during 75gOGTT. All the subjects collected urine samples at home before and 2 hours after consuming the commercially available test meal. UMI levels at wake-up time (UMIwake-up), before (UMIpremeal) and 2 hours after the test meal (UMI2h-postprandial) were measured using an enzymatic method. ΔUMI was defined as UMI2h-postprandial minus UMIpremeal. RESULTS: Differing from UG, UMI was stable at RT and 37°C. UMI was increased linearly along with an increase in PG, and no threshold for UMI was observed. UMI was closely associated with blood glucose parameters obtained from a 75gOGTT and hemoglobin A1c (HbA1c) at hospital after adjustment for age, sex, body mass index and serum creatinine. UMIwake-up, UMIpremeal, UMI2h-postprandial and ΔUMI at home were higher in diabetic subjects than non-diabetic subjects even after the above adjustment. Receiver operating characteristics curve (ROC) analyses revealed that for the screening of diabetes, the area under the curve for ROC for UMI2h-postprandial and ΔUMI (0.83 and 0.82, respectively) were not inferior to that for HbA1c ≥48 mmol/mol, which is the American Diabetes Association (ADA) criteria for diabetes. CONCLUSIONS: MI measurement in urine samples collected at home before and after the meal would be a simple, non-invasive and valuable screening method for diabetes.

Professional dietary coaching within a group chat using a smartphone application for weight loss: a randomized controlled trial.

PURPOSE: To test the effectiveness of professional dietary coaching via group chat using a smartphone application (app) for weight loss. METHODS: This study was a 12-week, assessor-blind, parallel-group, waitlist-controlled randomized trial that included a 4-week follow-up period (trial registration, UMIN000025340). Data were collected between October 2016 and May 2017 and were analyzed between July 2017 and January 2018. Participants were 112 overweight, obese, or abdominally obese Japanese adults, aged 20 to 64 years, with at least one cardiometabolic risk factor. Participants were randomized to the coaching group (n=75) or control group (n=37), with a ratio of 2:1. The coaching group received a commercial weight loss program characterizing dietary coaching by a certified nutrition professional via group chat delivered on a smartphone app. Participants posted photos of every meal into the group chat, and the certified professional gave immediate direct feedback and encouragement. The primary outcome was an 8-week weight change. Secondary outcomes included 8-week changes in cardiometabolic risk factors. The frequency of meal photo uploads was recorded as a measure of adherence. RESULTS: Of the 112 randomized participants, 93 (83.0%) and 81 (72.3%) completed 8-week and 12-week visits, respectively. Intention-to-treat analysis demonstrated significantly larger 8-week weight loss in the coaching group (-1.4 kg; 95% confidence interval [CI]: -2.0, -0.8 kg) than that in the control group (-0.1 kg; 95% CI: -0.6, 0.4 kg). Significantly larger improvements in triglyceride and glycated hemoglobin A1c levels were also obtained in the coaching group. These benefits, except for the triglyceride level, were maintained until week 12. The frequent upload of meal photos was associated with a larger 8-week weight loss in a dose-response fashion (P-value for trend <0.001). CONCLUSION: This smartphone-delivered commercial weight loss program characterized as dietary coaching via group chat resulted in modest but significant weight loss. Facilitating participants' active involvement in the program is necessary to achieve greater health benefits.

A study of urinary myo-inositol as a sensitive marker of glucose intolerance.

BACKGROUND: We assessed the possibility of using myo-inositol as a marker of glucose intolerance. METHODS: We measured urinary myo-inositol enzymatically before and 2 h after a 75-g oral glucose tolerance test in 564 volunteers, who were divided into four groups [normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and diabetes mellitus (DM)]. Furthermore, we classified NGT into NGT-A (2-h blood glucose <120 mg/dl and 2-h glucosuria <50 mg/dl) and NGT-B (remaining NGT subjects). We then compared deltamyo-inositol (myo-inositol/creatinine ratio: 2-h after glucose load--before load) of each group to investigate the relationship between glucose intolerance and deltamyo-inositol. RESULTS: The glucose tolerance of NGT-B appeared to have deteriorated compared with NGT-A as determined by blood glucose, insulin, and glucosuria. There was very little effect of gender or age on deltamyo-inositol in NGT-A. deltamyo-inositol was significantly higher than that in NGT-A (0.5+/-7.1 mg/g Cr) not only in IFG (8.7+/-19.5 mg/g Cr, P<0.0001), IGT (14.8+/-22.9 mg/g Cr, P<0.0001) and DM (79.5+/-37.1 mg/g Cr, P<0.0001), but in NGT-B (7.4+/-12.7 mg/g Cr, P<0.0001). With 2 mg/g Cr as a tentative cut-off for deltamyo-inositol to detect NGT-A, sensitivity and specificity were 68% and 72%, respectively. CONCLUSIONS: The deltamyo-inositol can be use of a non-invasive and sensitive marker for glucose intolerance.

Determination of urinary myo-inositol concentration by an improved enzymatic cycling method using myo-inositol dehydrogenase from Flavobacterium sp.

BACKGROUND: To determine myo-inositol more accurately, we improved the enzymatic cycling method. METHODS: We screened myo-inositol dehydrogenase (MIDH; EC.1.1.1.18) from Flavobacterium sp., which was highly specific to myo-inositol. We measured urinary myo-inositol/creatinine ratio 2 h after 75-g oral glucose tolerance test (2 h MI) of 71 volunteers, and investigated the relationship between diabetes and urinary myo-inositol concentration. RESULTS: The calibration curve was linear (r = 1.00) up to 2000 micromol/l, and the detection limit was 10 micromol/l. Within-run and between-run CVs were 0.5-1.1% and 0.4-1.3%, respectively. The 2 h MI of impaired fasting glycemia (IFG; 65.1 +/- 46.6 mg/g Cr, P < 0.005), impaired glucose tolerance (IGT; 85.0 +/- 73.7 mg/g Cr, P < 0.001) and diabetes (163.4 +/- 73.7 mg/g Cr, P < 0.0001) increased significantly compared with that of normal glucose tolerance (NGT; 24.0 +/- 14.4 mg/g Cr). From receiver operating characteristic analyses on 2 h MI, with 50 mg/g Cr as a tentative cutoff value to detect diabetes, the sensitivity and specificity were 100% and 77%, respectively. With 40 mg/g Cr as a tentative cutoff value to detect NGT, the sensitivity and specificity were 74% and 85%, respectively. CONCLUSIONS: The myo-inositol measurement method demonstrated high specificity and yielded accurate results. The results of clinical trials suggested that 2 h MI could not only determine diabetes but also distinguish IFG and IGT from NGT.