Impaired glucose metabolism in patients with Turner syndrome

Abstract

Objective To investigate the glucose metabolism disorder status and clinical features in patients with Turner syndrome (TS). Methods A total of 61 patients with TS was included in this study. Oral glucose tolerance test (OGTT), glycated hemoglobin A1c (HbA1c) and autoimmune antibodies, including glutamic acid decarboxylase antibody (GADA), islet cell antibodies (ICA) and islet cell antigen 2 antibody (IA-2A) were measured in these patients. The t test and Logistic regression were used for statistical analysis. Results (1) The mean age of all the patients was (15.2±4.9) years, and mean body mass index (BMI) was (20.5±3.5) kg/m2. (2) HbA1c was 5.4%±1.4%. About 31.5% (17/54) of the patients had abnormal glucose metabolism: 4 patients were diagnosed as diabetes, 4 cases were isolated impaired fasting glucose (IFG), 6 cases were impaired glucose tolerance (IGT), and 3 cases were combined IFG and IGT. Compared to healthy female adolescents (n=40), patients with TS had higher homeostasis model assessment of insulin resistance (HOMA-IR) (3.4±2.7 vs 2.0±0.7, t=3.321, P=0.001), larger areas under glucose curve [(22.3±8.8) vs (17.7±2.4) mmol·h/L, t=2.339, P=0.022] and insulin curve [(284±178) vs (175±86) mU·h/L, t=3.533, P=0.001] during OGTT. Only one patient had one test positive for IA-2A while her glucose tolerance test was normal. (3) Patients were classified into three subgroups according to their karyotypes: 45, XO group (n=23); isoXq group (n=17), including patients with 46X, i(X)(q) and 45, XO/46X, i(X)(q); and other karyotype type group (n=14). The percentage of abnormal glucose metabolism was 47.8% (11/23), 23.5% (4/17), and 14.3% (2/14) in three groups, respectively. There was no statistical significance among the three groups (χ2=3.764, P>0.05). Conclusion Compared to healthy female adolescents, young patients with TS have more severe insulin resistance and higher risks for abnormal glucose metabolism. Patients with 45, XO karyotype have higher inclination for abnormal glucose metabolism than patients with other karyotypes. Key words: Turner syndrome; Karyotyping; Glucose metabolism