The Preservation of Insulin Sensitivity in Obese Women without Diabetes
Chardpraorn Ngarmukos MD*, Suwanee Chanprasertyothin MSc**, Gobchai Puavilai MD*, Boonsong Ongphiphadhanakul MD*
Affiliation : * Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok ** Research Center, Ramathibodi Hospital, Mahidol University, Bangkok
Objective : To assess insulin sensitivity, pancreatic beta-cell function, and compare circulating levels of
adiponectin and ghrelin in obese women with and without diabetes.
Material and Method: Ninety-nine obese women with a body mass index (BMI) > 25 kg/m2 and age at least 40
years without previous history of diabetes participated in this study. Oral glucose tolerance test was performed
in all subjects. Serum for insulin, adiponectin, and ghrelin were obtained at baseline. Data were expressed as
mean + SEM.
Results : Oral glucose tolerance test revealed 66 non-diabetic (ND) and 33 diabetic (D) subjects. Despite a
similar degree of obesity, women without diabetes had near normal insulin sensitivity (ND, 105.7 + 6.4%; D,
62.3 + 5.9%; p < 0.001) and beta cell function (ND, 95.4 + 3.0%; D, 79.0 + 6.1%; p < 0.001) as assessed by
the HOMA model. Non-diabetic subjects had higher serum adiponectin levels despite similar BMI (ND, 8.3 +
0.4 mg/ml; D, 6.3 + 0.4 mg/ml; p < 0.01). Obese subjects with diabetes had lower serum ghrelin levels than
obese non-diabetic subjects (ND, 1027.2 + 32.0 pg/ml; D, 875.1 + 34.6 pg/ml; p < 0.05).
Conclusion : Obese women without diabetes have less pancreatic beta cell dysfunction and higher insulin
sensitivity than obese women with diabetes. Higher circulating adiponectin may play protective roles in
obese non-diabetic subjects, but the significance of higher ghrelin level should be further explored.
Keywords : Obesity, Diabetes, Insulin sensitivity, Adiponectin, Ghrelin
