Higher BMI and Low Insulin Sensitivity Significantly Raise Stroke Risk: Study

Stroke is a major cause of disability and mortality globally and is the focus here of consideration and treatment to modifiable risk factors. Though BMI is a well-established marker of adiposity, eGDR is a significant marker of insulin sensitivity. The evidence from previous studies has shown that both of these factors are associated with stroke risk, but this study sheds light on new information by examining their combined effect.

The research used information from 7,212 adults over the age of 45 years who were involved in the China Health and Retirement Longitudinal Study (CHARLS). The participants were followed for 7 years, and their BMI and eGDR values were measured.

BMI Measurement:

• Computation as weight in kilograms divided by height in meters squared (kg/m²).

• Obesity was classified as BMI greater than 28 kg/m².

eGDR Calculation:

• Estimated via a standard formula that mirrors insulin sensitivity.

• Lower eGDR values indicate reduced insulin sensitivity.

Stroke Assessment:

• New-onset stroke was determined based on self-reported diagnosis confirmed by medical professionals.

Analysis Techniques:

• Cox proportional hazards models were used to assess the association between BMI, eGDR, and stroke risk.

• Mediation analysis evaluated BMI’s role in the relationship between eGDR and stroke.

• Subgroup analyses were performed based on age, sex, and BMI categories.

Key Findings

Stroke Incidence:

• During the 7-year follow-up, 587 participants (8.14%) experienced new-onset stroke.

Independent Associations:

• Greater BMI was significantly correlated with greater risk of stroke.

• Increased stroke risk was also found for lower eGDR, further establishing the involvement of lower insulin sensitivity.

Effects of Interaction:

• Subjects who were both obese (BMI >28 kg/m²) and of low eGDR experienced highest stroke risk with an hazard ratio (HR) of 2.63 (95% CI: 1.78–3.89).

Mediation Analysis:

• The association of new-onset stroke with lower eGDR was significantly mediated by BMI, for 16.78%.

Subgroup Analysis

• The relationship between BMI, eGDR, and stroke risk held across various categories of age, sex, and BMI.

The CHARLS study has confirmed that greater BMI and lesser eGDR highly enhance the threat of new-onset stroke among middle-aged and older adults, with greatest danger in those having both obesity and reduced insulin sensitivity. Reducing both adiposity and insulin resistance by targeted interventions may be a practical approach for lowering stroke threat, providing an appealing method to enhance cardiovascular outcome in high-risk individuals.

Reference:

Yu T, Shao D-M, Lv T and Xiong Y-J (2025) Joint association of estimated glucose disposal rate and body mass index with new-onset stroke. Front. Neurol. 16:1529752. doi: 10.3389/fneur.2025.1529752