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

Background Obesity is a well-known risk factor for early glycaemic dysregulation. In contrast, among non-obese patients (normal weight or overweight), glycaemic disturbances may remain under-recognised. This study aimed to evaluate the association between anthropometric measures and glycaemic control indicators in newly diagnosed, untreated obese and non-obese patients with type 2 diabetes mellitus (T2DM) in Uzbekistan. Methods A cross-sectional study was conducted among 104 untreated, newly diagnosed T2DM patients at the Samarkand branch of the Republican Specialised Endocrinology Hospital, Uzbekistan. Body mass index (BMI), waist circumference (WC), fasting plasma glucose (FPG), oral glucose tolerance test (OGTT), and glycated haemoglobin (HbA1c) were recorded. Patients were categorised as obese (BMI ≥ 30 kg/m²) or non-obese (BMI < 30 kg/m²). Independent Student’s t -tests and Mann–Whitney U tests were used to compare variables between groups. Age-adjusted partial Spearman correlations were applied to evaluate associations between anthropometric parameters and glycaemic markers. 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 (≥ 30.0 kg/m²) patients (n = 30) were significantly younger (47.7 ± 9.32 years) than non-obese patients (n = 74; 53.85 ± 12.05 years; p = 0.014), and FPG levels were significantly higher in obese patients (13.4 ± 2.97 mmol/L) than in non-obese patients (11.89 ± 2.94 mmol/L; p = 0.02). Age-adjusted partial Spearman correlation analysis in all patients showed positive associations between BMI and FPG (ρ = 0.212, p < 0.05), and between WC and both FPG and OGTT, with weak-to-moderate correlations (ρ = 0.251 and 0.23, respectively; p < 0.05). In non-obese patients, WC was weakly to moderately positively correlated with FPG and OGTT (ρ = 0.236 and ρ = 0.297, respectively; p < 0.05), whereas no significant correlations were observed in obese patients. Conclusion Although waist circumference was elevated among non-obese (< 30.0 kg/m²) patients (97.39 ± 5.58 cm), it showed only a weak positive correlation with glycaemic indicators. These findings suggest that central obesity may play a modest but clinically relevant role in the early identification of glycaemic dysregulation among non-obese individuals.