Central obesity and glycaemic control in newly diagnosed type 2 diabetes mellitus patients: evidence from Uzbekistan

BACKGROUND: Obesity is a well-established risk factor for impaired glycaemic regulation; however, a substantial proportion of individuals with type 2 diabetes mellitus develop dysglycaemia despite not being obese by body mass index (BMI). Central adiposity may better reflect metabolic risk in such patients. This study aimed to examine the associations between anthropometric measures (BMI and waist circumference) and glycaemic parameters among newly diagnosed, untreated patients with type 2 diabetes mellitus in Uzbekistan. METHODS: A cross-sectional study was conducted among 104 untreated, newly diagnosed T2DM patients at a tertiary endocrinology centre in Samarkand, Uzbekistan. BMI, waist circumference (WC), fasting plasma glucose (FPG), oral glucose tolerance test (OGTT), and glycated haemoglobin (HbA1c) were assessed. Patients were classified as obese (BMI ≥ 30 kg/m²) or non-obese (BMI < 30 kg/m²). Group comparisons were performed using Student's t-test or Mann-Whitney U test, as appropriate. Multivariable linear regression analyses were performed to examine independent associations between anthropometric measures (WC and BMI) and glycaemic parameters, adjusting for age, sex, and smoking status. RESULTS: The study included 104 newly diagnosed T2DM patients (mean age 52.1 ± 11.7 years; 61.5% men), with a median BMI of 28.4 [26.53-30.28] kg/m² and a mean WC of 99.5 ± 6.65 cm. Obese patients (BMI ≥ 30.0 kg/m²; n = 30) were significantly younger than non-obese patients (n = 74; 47.7 ± 9.32 vs. 53.85 ± 12.05 years; p = 0.014) and had higher FPG levels (13.4 ± 2.97 vs. 11.89 ± 2.94 mmol/L; p = 0.02). In fully adjusted models including both BMI and WC, WC and smoking status were independently associated with FPG and OGTT values, whereas BMI was not. No significant associations were observed between anthropometric measures and HbA1c. CONCLUSION: Waist circumference was independently associated with fasting plasma glucose and oral glucose tolerance test values in newly diagnosed T2DM patients, providing information complementary to BMI. These findings highlight the potential value of assessing central adiposity at the time of diabetes diagnosis. Causal relationships cannot be inferred due to the cross-sectional design. CLINICAL TRIAL REGISTRATION: Not applicable.