E. Hamo-Tchatchouang

A large proportion of prediabetes and diabetes goes undiagnosed when only fasting plasma glucose and/or HbA1c are measured in overweight or obese patients

AIMS The purposes of the study were to determine the prevalence of unrecognized dysglycaemia in overweight (body mass index [BMI] 25-29.9 kg/m(2)) and obese (BMI ≥30 kg/m(2)) patients, to assess the extent to which measures of fasting plasma glucose (FPG) and/or HbA(1c), compared with oral glucose tolerance tests (OGTTs), misdiagnose dysglycaemia, and to determine the factors associated with an isolated abnormal post-OGTT glucose value. METHODS OGTT was performed and HbA(1c) was measured in 1283 inpatients with BMI scores ≥ 25 kg/m(2) and no history of dysglycaemia. RESULTS Prediabetes was found in 257 (20.0%) subjects (197 with impaired glucose tolerance, 29 with impaired fasting glucose, 31 with both) and diabetes in 77 (6.0%), including 22 with FPG ≥ 7 mmol/L (WHO definition). The sensitivity of FPG >6 mmol/L, FPG >5.5 mmol/L, HbA(1c) ≥ 6% and the recommendations of the French National Agency of Accreditation and Evaluation in Health Care (ANAES) to identify patients with abnormal OGTTs was 29.9, 41.3, 36.8 and 15.6%, respectively. The factors that were independently associated with diabetes in obese women with FPG <7 mmol/L were age (per 10 years: OR 1.54 [1.00-2.11]; P=0.049) and FPG (OR 6.1 [1.4-30.0]; P=0.014), whereas age (OR 1.26 [1.09-1.44]; P<0.01) and waist circumference (per 10 cm: OR 1.17 [1.01-1.33]; P<0.05) were independently associated with dysglycaemia in obese women with FPG <6.1 mmol/L. CONCLUSION In overweight and obese patients: dysglycaemia is commonly seen; FPG alone, compared with OGTT, failed to diagnose 70% of dysglycaemia cases; FPG >5.5 mmol/L and HbA(1c) ≥ 6.0% are not necessarily substitutes for OGTT; and older age and larger waist circumference should be used to select those obese women with normal FPG who might further benefit from OGTTs to diagnose dysglycaemia.

Use of clinical scores to detect dysglycaemia in overweight or obese women

AIMS To test if the use of either HbA(1c) level or calculated clinical scores including two published scores and a new score (the Bondy score) could help in selecting overweight or obese women who should benefit from oral glucose tolerance test (OGTT) to detect dysglycaemia. METHODS The French Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) score and the Finnish Diabetes risk score (Findrisk) were calculated, whereas the Bondy score was built in a development sample of 698 women, BMI 37±7 kg/m(2), without known diabetes. External validation was performed in a validation sample of 212 women. RESULTS A dysglycaemia (according to OGTT results, WHO criteria) was diagnosed in 161 (23.1%) patients. Sensitivity of fasting plasma glucose (FPG)≥6.1 mmol/l and HbA(1c)≥6% to identify dysglycaemia were respectively 27 and 41%. Areas under Receiver Operator Curve (AROC) of HbA(1c), DESIR score and Findrisk to detect dysglycaemia were 0.630 [95% confidence interval 0.580-0.680], 0.606 [0.561-0.652] and 0.635 [0.588-0.683], respectively. The Bondy score, based on age and waist circumference, had a better AROC (0.674 [0.626-0.721]) than the DESIR score (P<0.05). These performances were confirmed in the validation sample. Performing OGTT only in subjects with a Bondy score≥4 (41% of the sample) had a sensitivity of 61% and a better net benefit (0.128) than measuring FPG in all subjects (0.069). CONCLUSION Performing OGTT in obese women selected on a simple clinical score is more sensitive to identify dysglycaemia than measuring FPG in all of them and may be cost-effective.

O92 HbA1c, seuil de glycémie à jeun moindre et recommandations de l’Agence Nationale d’Accréditation et d’Évaluation des Soins (ANAES) ne peuvent pas se substituer à la charge en glucose pour le diagnostic des dysglycémies

Introduction La charge orale en glucose (COG) n’est actuellement pas recommandee en France pour le diagnostic des dysglycemies. Des methodes de substitution ont ete proposees, comme diminuer le seuil de glycemie a jeun (GAJ), doser l’HbA1c et selectionner la population a depister. L’objectif de l’etude etait de determiner la prevalence des dysglycemies meconnues, incluant le diabete, l’hyperglycemie a jeun (HAJ) et l’intolerance au glucose (IG) dans une cohorte importante de patients en surpoids ou obeses ; l’efficacite de ces methodes de substitution ; et les principaux facteurs predictifs de dysglycemie dans cette population. Patients et Methodes Une COG a ete realisee chez 1 283 patients sans dysglycemie connue hospitalises pour surpoids ou obesite. Resultats Un etat pre-diabetique a ete diagnostique chez 257 (20 %) patients (197 IG, 29 HAJ et 31 IG+HAJ) et un diabete chez 77 (6 %) patients, dont 22 avec une GAJ = 7 mmol/l. Une GAJ = 6 mmol/l, une GAJ = 5,5 mmol/l, une HbA1c = 6 % et suivre les recommandations de l’ANAES auraient respectivement identifie 29,9 ; 41,3 ; 36,8 et 15,6 % des patients avec une COG anormale. Les facteurs predictifs independants de dysglycemie en analyse multivariee etaient l’âge (odds ratio 1,031 [intervalle de confiance a 95 % : 1,018–1,044], p Conclusion Chez les patients en surpoids ou obeses, a- la prevalence des dysglycemies est elevee ; b- la GAJseule comparee a la COGne diagnostique que 31 % des diabetes ou prediabetes ; c- une GAJ > 5,5 mmol/L et une HbA1c = 6,0 % ne peuvent pas se substituer a la COG ; d- les facteurs predictifs principaux de dysglycemie sont l’âge, le tour de taille et l’hypertension et pourraient etre utilises en priorite pour la selection des sujets a depister.