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.
Sarashina
Gen
G
Fifth Department of Internal Medicine, Tokyo Medical University (Kasumigaura Hospital), 3-20-1 Chuou Ami, Inashiki Ibaraki 300-0395, Japan.
Yamakoshi
Masaru
M
Noritake
Masayuki
M
Takahashi
Mamoru
M
Kure
Masahiko
M
Katsura
Yoshiya
Y
Shiomi
Hiroshi
H
Tsuboi
Isami
I
Kawazu
Shoji
S
Yamagata
Fumio
F
Tominaga
Makoto
M
Matsuoka
Takeshi
T
D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000652:urine; D016022:Case-Control Studies; D005260:Female; D018149:Glucose Intolerance / Q000175:diagnosis* / Q000652:urine; D006801:Humans; D007294:Inositol / Q000652:urine*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012737:Sex Factors
D015415:Biomarkers; D007294:Inositol