No genetic causality between obesity and benign paroxysmal vertigo: A two-sample Mendelian randomization study

Area of Science:

• Genetics
• Epidemiology
• Otolaryngology

Background:

• Obesity is a growing global health concern with numerous comorbidities.
• Benign paroxysmal vertigo (BPV) is a common vestibular disorder affecting quality of life.

Purpose of the Study:

• To investigate the potential causal relationship between obesity and benign paroxysmal vertigo (BPV) using a Mendelian randomization approach.
• To analyze genetic associations for two distinct obesity classifications: obesity due to excessive calories and other or unspecified obesity.

Main Methods:

• Utilized genome-wide association study (GWAS) data from the FinnGen database for obesity and BPV.
• Selected independent single nucleotide polymorphisms (SNPs) as instrumental variables based on genomic significance (p < 5 × 10⁻⁸).
• Employed random-effects inverse variance weighting (IVW) as the primary statistical analysis method, assessing heterogeneity and pleiotropy.

Main Results:

• An outlier SNP (rs12956821) was identified and removed from the analysis for obesity due to excessive calories.
• Post-outlier removal, analyses showed no significant heterogeneity or horizontal pleiotropy.
• Results indicated no statistically significant causal effect of obesity due to excessive calories (p = 0.481; OR = 0.941) or other/unspecified obesity (p = 0.640; OR = 0.964) on BPV.

Conclusions:

• This genetic analysis did not establish a causal link between the investigated obesity types and benign paroxysmal vertigo.
• The findings suggest that genetic predisposition to obesity is unlikely to be a direct cause of BPV.