Metabolic and lifestyle factors in relation to senile cataract: a Mendelian randomization study

Abstract

We conducted a Mendelian randomization study to determine the associations of body mass index (BMI), type 2 diabetes (T2D), systolic blood pressure (SBP), coffee and alcohol consumption and smoking initiation with senile cataract. Independent single nucleotide polymorphisms associated with the metabolic and lifestyle factors at the p < 5 × 10–8 were selected as instrument variables. Summary-level data for senile cataract were obtained from the FinnGen consortium (20,157 cases and 154,905 non-cases) and UK Biobank study (6332 cases and 354,862 non-cases). Higher genetically predicted BMI and SBP and genetic predisposition to T2D and smoking initiation were associated with an increased risk of senile cataract. The combined odds ratios were 1.19 (95% confidence interval (CI) 1.09–1.29; p < 0.001) per one standard deviation increase in BMI (~ 4.8 kg/m2), 1.13 (95% CI 1.04–1.23; p = 0.004) per 10 mmHg increase in SBP, 1.06 (95% CI 1.03–1.09; p < 0.001) per one unit increase in log-transformed odds ratio of T2D, and 1.19 (95% CI 1.10–1.29; p < 0.001) per one standard deviation increase in prevalence of smoking initiation. Genetically predicted coffee consumption showed a suggestive association with senile cataract (odds ratio per 50% increase, 1.18, 95% CI 1.00–1.40; p = 0.050). This study suggests causal roles of obesity, T2D, SBP and smoking in senile cataract.

Appraising the causal role of smoking in multiple diseases: A systematic review and meta-analysis of Mendelian randomization studies

“…After exclusion of studies using overlapping or same outcome data, 29 articles based on non-overlapping populations were eligible for inclusion in one or more meta-analyses. The number of studies included in each outcome category was seven for circulatory system diseases, 4 , 5 , 6 , 7 , 8 , 9 , 10 six for digestive system diseases, 11 , 12 , 13 , 14 , 15 , 16 six for nervous system diseases, 17 , 18 , 19 , 20 , 21 three for musculoskeletal system outcomes, 22 , 23 , 24 two for endocrine and metabolic diseases, 25 , 26 two for eye diseases, 27 , 28 and four for neoplasms. 29 , 30 , 31 , 32 In addition to the included studies, 123 de novo MR analyses ( n =51 for smoking initiation, n = 72 for lifetime smoking) were conducted.…”

“…During the last few years, the potential causal association between smoking and risk of different diseases has been investigated using the Mendelian randomization (MR) approach. 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 MR is a method that utilizes genetic variants associated with a difference in the exposure (e.g., smoking liability) as instrumental variable for the exposure to determine the causal role of the exposure in the development of disease. 33 The MR design mitigates confounding because genetic alleles are randomly allocated when passed from parents to offspring and therefore usually not related to other risk factors.…”

Health effects of milk consumption: phenome-wide Mendelian randomization study

“…Notably, the participants in this study were in high cardiovascular risk (e.g., with a high prevalence of diabetes, hypercholesterolemia, and hypertension) [38], which is different from the UK Biobank individuals with a generally good health status. Our recent MR study found causal associations of several cardiovascular risk factors with an increased risk of cataract [39]. In the PREvención con DIeta MEDiterránea Study, participants with at least one cardiovascular risk factor were at a high risk of cataract.…”

The Epigenetic Effects of Coffee

“…In 2022, it was genetically predicted that coffee consumption showed a suggestive association with senile cataract [ 38 ]. In two studies, it was found that higher coffee consumption was associated with a higher risk of primary open-angle glaucoma (POAG) and open-angle glaucoma (OAG) compared with those who did not drink coffee [ 39 , 40 ].…”