Key Insight:

New research reveals that diabetes and prediabetes are linked to accelerated brain aging, with those affected experiencing brain age gaps of 2.29 and 0.50 years, respectively. This effect is more pronounced in men and individuals with poor cardiometabolic health. However, a healthy lifestyle may help slow down this aging process.

Study Overview:

Diabetes is well known for increasing the risk of cognitive decline, dementia, and brain shrinkage, but there has been uncertainty about the effects of prediabetes. Moreover, it hasn’t been clear whether a healthy lifestyle could counteract these risks. A large-scale study of 31,229 dementia-free adults (average age: 54.8, 53% women) from the UK Biobank sought to address this, including 13,518 individuals with prediabetes and 1,149 with diabetes.

Participants’ blood sugar levels were assessed through their medical history, medication usage, and A1c levels. Brain aging was measured using MRI scans, and brain age gaps were determined by comparing a person’s chronological age to their estimated brain age. Additionally, the researchers explored how factors like sex, cardiometabolic health, and lifestyle choices influence brain aging. A “healthy lifestyle” was defined as avoiding smoking, drinking alcohol in moderation, and maintaining high levels of physical activity.

Major Findings:

The study found that both prediabetes and diabetes were associated with an older brain compared to those with normal blood sugar levels. Specifically:

• Prediabetes led to a brain age gap of 0.50 years, while diabetes resulted in a gap of 2.29 years.
• The effects of diabetes were more severe in men and those with higher cardiometabolic risk factors.

In a smaller group of 2,414 participants who had two brain MRI scans over time, diabetes was linked to an annual increase in brain age of 0.27 years. Elevated A1c levels also contributed to a greater brain age gap, though prediabetes did not show this effect.

Crucially, living a healthy lifestyle significantly reduced the brain aging effect of diabetes, cutting the brain age gap by 1.68 years. This finding underscores the importance of lifestyle interventions for individuals with diabetes or prediabetes.

Practical Implications:

“Our study underscores diabetes and prediabetes as key areas for lifestyle interventions to protect brain health,” the authors emphasized. Implementing healthy habits like regular exercise, moderate alcohol consumption, and avoiding smoking may slow brain aging in those with diabetes.

Study Source:

This research, led by Abigail Dove from the Karolinska Institutet’s Aging Research Center, was recently published in Diabetes Care.

Study Limitations:

The findings are based on volunteers from the UK Biobank, potentially limiting their general applicability due to a healthy volunteer bias. Furthermore, the study did not account for diet in its healthy lifestyle definition, and A1c levels were only measured once, preventing a look at changes in blood sugar control over time. There’s also the possibility that brain aging may itself contribute to difficulties in managing diabetes, creating a feedback loop.

Disclosures:

The study was funded by several Swedish institutions, including the Swedish Research Council and Marianne and Marcus Wallenberg Foundation. No conflicts of interest were reported by the authors.

Source: https://www.medscape.com/viewarticle/healthy-lifestyle-mitigates-brain-aging-diabetes-2024a1000h58