Pre-diabetes may contribute to stroke risk but that depends largely on how prediabetes is defined, the authors of a new meta-analysis pointed out in the British Medical Journal. Since definitions of prediabetes vary, it’s difficult to determine the exact degree of risk prediabetes presents.

To clarify this, researchers analyzed 15 studies that assess the association of prediabetes and stroke. When defined as a fasting glucose of 100-125 mg/dL, prediabetes did not increase stroke risk. But when the defining numbers shifted to 110-125 mg/dL, prediabetes increased stroke risk by 21%. That risk grew significantly when the threshold for prediabetes included impaired glucose tolerance or a combination of impaired glucose tolerance and fasting glucose.

Using the categories of prediabetes, diabetes or no diabetes may be too simplistic argued John Treadwell, senior research analyst at the ECRI institute. Instead diabetes may fall into a continuum of insulin resistance, Treadwell observed.

Regardless of the definitions, researchers concluded that “the risk of stroke seems to rise progressively across the spectrum of insulin resistance.”

Reference

Lee M, et al. Effect of pre-diabetes on future risk of stroke: meta-analysis. British Medical Journal 2012; 344: doi 10.1136/bmj.e3564.