Causal Association Between Lifestyle Behavior and Potential Risk Factors With Blepharoptosis

Background Blepharoptosis is among the most common disorders of eyelid malposition that may influence appearance and damage visual function, and both of these can have negative effects on the quality of life. Various types of blepharoptosis have been reported, including neurogenic, traumatic, congenital, mechanical, psychogenic, and myogenic, while about 15%–25% remain uncertain. Method To determine the targets for preventing blepharoptosis and its associated disease burden, we employed a two‐sample Mendelian randomization approach to explore the causal relationships between reported potential risk factors and lifestyle behaviors and blepharoptosis. We chose genetic variants ( p < 5 × 10 −8 ) related to prediabetic status, obesity parameters, smoking, alcohol and coffee consumption, hypertension, education level, physical activity, and sleep duration from European‐descent genome‐wide association studies. The genetic associations with blepharoptosis were derived from the FinnGen Study, included 1349 cases and 203,231 controls. Inverse‐variance weighted was mainly used for statistical analyses. Results Genetically predicted leisure screen time (odds ratio per 1 standard deviation [95% confidence interval], 1.79 [1.23–2.60]) was associated with higher odds of blepharoptosis. There is indicative evidence that a higher body mass index (BMI) and current smoking are associated with higher blepharoptosis odds, whereas physical activity and smoking cessation are associated with lower blepharoptosis odds. No association with other genetically predicted factors was observed. Conclusion The Mendelian randomization study identified current smoking status and BMI as causal risk factors, and smoking cessation as protective factor for blepharoptosis. This suggests that these modifiable risk factors are crucial targets for preventing blepharoptosis.