Does body mass index and height influence the incident risk of ischemic stroke in newly diagnosed type 2 diabetes subjects?

Objective: To estimate the incident risk of ischemic stroke (IS) in newly diagnosed type 2 diabetes (T2D) subjects according to different body mass index (BMI) and height categories.

Methods: A total of 25,130 newly diagnosed T2D subjects were included in this study. All T2D subjects were enrolled consecutively from the Chronic Disease Surveillance System (CDSS) of Ningbo. Standardized incidence ratio (SIR) and its 95% confidence interval (95% CI) stratified by BMI categories and height quartiles were used to estimate the incident risk of IS in T2D subjects.

Results: In total, 22,795 subjects completed the follow-up. Among them, 1268 newly diagnosed IS cases were identified, with 149,675 person-years. The SIRs of normal BMI (18.5-24.0 kg/m2), overweight (24.0-28.0 kg/m2), and obese (≥28.0 kg/m2) in overall subjects were 2.56 (95% CI 1.90-3.13), 2.13 (95% CI 1.90-3.13), and 1.87 (95% CI 1.29-2.43), respectively (Ptrend < 0.01), comparing to the general population of Ningbo. For each 1 kg/m2 increment in BMI, the SIR was 0.948 (95% CI 0.903-0.999). For height quartiles, the SIRs of male subjects in quartile 1 (<160 cm), quartile 2 (161-165 cm), quartile 3 (165-170 cm), and quartile 4 (≥171 cm) were 2.27 (95% CI 1.99-2.56), 2.01 (95% CI 1.67-2.45), 1.37 (95% CI 1.05-1.68), and 0.91 (95% CI 0.40-1.32), respectively (Ptrend < 0.01). While for female subjects, the SIRs in quartile 1 (<155 cm), quartile 2 (156-160 cm), quartile 3 (161-165 cm), and quartile 4 (≥166 cm) were 3.57 (95% CI 3.11-3.49), 2.96 (95% CI 2.61-3.31), 1.94 (95% CI 1.51-2.36), and 1.71 (95% CI 0.95-2.47), respectively (Ptrend < 0.01).

Conclusion: Compared to the general population of Ningbo, T2D subjects had a higher incident risk of IS. Furthermore, the IS incident risk was not only higher in newly diagnosed T2D subjects with normal BMI but also lower in taller newly diagnosed T2D subjects.