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Stroke and frailty index: a two-sample Mendelian randomisation study.

Jiangnan Wei1, Jiaxian Wang1, Jiayin Chen1

  • 1Department of Nursing, Zhuhai Campus of Zunyi Medical University, No. 368 Jinwan Road, Zhuhai, Guangdong, China.

Aging Clinical and Experimental Research
|May 22, 2024
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Summary

This study found a causal link between stroke and frailty index (FI), suggesting genetic factors contribute to frailty in stroke patients. The findings support a genetic connection between stroke and frailty.

Keywords:
FrailtyGenetic analysesMendelian randomizationStroke

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Area of Science:

  • Genetics
  • Neurology
  • Gerontology

Background:

  • Observational studies indicate an increased risk of frailty in stroke patients.
  • Evidence for a causal relationship between stroke and frailty remains limited.
  • This study aimed to establish a causal link between stroke and the frailty index (FI).

Purpose of the Study:

  • To investigate the potential causal relationship between stroke and frailty index (FI) using genetic data.
  • To leverage Mendelian randomization to infer causality between stroke and frailty.

Main Methods:

  • Genome-wide association studies (GWAS) data for stroke (MEGASTROKE Consortium) and frailty index (UK BioBank, Swedish TwinGene) were pooled.
  • Two-sample Mendelian randomization (MR) analyses were conducted using inverse variance weighting (IVW), weighted median, and other methods.
  • Heterogeneity and horizontal pleiotropy were assessed using Cochran's Q test and MR-Egger regression.

Main Results:

  • A significant causal correlation was observed between stroke genetic prediction and FI (OR 1.104, P < 0.001).
  • Significant causal links were found for ischemic stroke (IS) (OR 1.037, P = 0.005) and large-vessel atherosclerotic stroke (LAS) (OR 1.081, P < 0.001).
  • No causal relationship was detected between cardioembolic stroke (CES) and FI; no significant heterogeneity or pleiotropy was found.

Conclusions:

  • This Mendelian randomization study provides robust evidence for a causal relationship between stroke and frailty index.
  • The findings offer novel insights into the genetic underpinnings of frailty in the context of stroke.
  • Genetic predisposition to stroke may contribute to the development of frailty.