Causal relationship between the duration of mobile phone use and risk of stroke: A Mendelian randomization study

Abstract

Overview

This study investigates the causal relationship between the duration of mobile phone use (DMPU) and the risk of stroke using a Mendelian randomization (MR) approach. Independent single nucleotide polymorphisms (SNPs) from genome-wide association study (GWAS) datasets were used as instrumental variables to determine the effects of DMPU on various stroke types, including intracerebral hemorrhage, ischemic stroke, and its subtypes—cardioembolic infarction, small-vessel disease, and large artery atherosclerosis (LAAS). The primary MR method utilized was inverse-variance weighting, with additional sensitivity analyses performed.

Findings

• Ninety SNPs associated with stroke from GWAS datasets were selected as instrumental variables.
• Inverse-variance weighted analysis demonstrated a significant causal link between DMPU and an increased risk of LAAS (odds ratio [OR] = 1.120; 95% confidence interval [CI] = 1.005-1.248; P = .040).
• No significant genetic associations were observed for overall stroke, intracerebral hemorrhage, ischemic stroke, cardioembolic infarction, or small-vessel disease.
• MR-Egger regression suggested that multidimensionality was unlikely to bias the results, and tests for heterogeneity or asymmetry indicated robust findings.

Conclusion

The investigation confirmed a causal relationship between longer durations of mobile phone use and increased risk of LAAS—a subtype of stroke. These findings suggest implications for public health strategies and policy development addressing electromagnetic field (EMF) exposure from mobile devices. Importantly, this highlights a direct connection between environmental EMF exposure and specific cerebrovascular risks.