Prebaseline Selection Bias in the Estimated Effect of T2D on Cognitive Decline: Cross-National Simulations
2024

Impact of Type-2 Diabetes on Cognitive Decline

Sample size: 2000 publication Evidence: moderate

Author Information

Author(s): Zhang Pengyuan (Kelvin), Mani Sneha, Kobayashi Lindsay, Gross Alden, Weuve Jennifer, Andrews Ryan

Hypothesis

How does pre-baseline survival bias affect the estimated impact of type-2 diabetes on cognitive decline across different countries?

Conclusion

Pre-baseline survival bias can significantly underestimate the effect of type-2 diabetes on cognitive decline by up to 34% in cross-national studies.

Supporting Evidence

  • Selection bias can arise from differential mortality in study populations.
  • Individuals who survive to study enrollment may differ significantly from those who do not.
  • The study simulated cohorts to quantify the impact of pre-baseline survival bias.

Takeaway

If people who are sick don't make it into studies, we might think that diabetes doesn't affect brain health as much as it really does.

Methodology

Simulations of large country-specific cohorts were conducted to assess the impact of type-2 diabetes on cognitive decline.

Potential Biases

Selection bias due to differential mortality prior to study enrollment.

Limitations

The study relies on simulations, which may not capture all real-world complexities.

Participant Demographics

Simulated cohorts from the US, India, and China.

Digital Object Identifier (DOI)

10.1093/geroni/igae098.2081

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication