The Association of Urinary Sodium Excretion with Glaucoma and Related Traits in a Large United Kingdom Population.
Stuart KV., Biradar MI., Luben RN., Dhaun N., Wagner SK., Warwick AN., Sun Z., Madjedi KM., Pasquale LR., Wiggs JL., Kang JH., Lentjes MAH., Aschard H., Kim J., Foster PJ., Khawaja AP., Modifiable Risk Factors for Glaucoma Collaboration None., UK Biobank Eye and Vision Consortium None., International Glaucoma Genetics Consortium None.
PurposeExcessive dietary sodium intake has known adverse effects on intravascular fluid volume and systemic blood pressure, which may influence intraocular pressure (IOP) and glaucoma risk. This study aimed to assess the association of urinary sodium excretion, a biomarker of dietary intake, with glaucoma and related traits, and determine whether this relationship is modified by genetic susceptibility to disease.DesignCross-sectional observational and gene-environment interaction analyses in the population-based UK Biobank study.ParticipantsUp to 103 634 individuals (mean age: 57 years; 51% women) with complete urinary, ocular, and covariable data.MethodsUrine sodium:creatinine ratio (UNa:Cr; mmol:mmol) was calculated from a midstream urine sample. Ocular parameters were measured as part of a comprehensive eye examination, and glaucoma case ascertainment was through a combination of self-report and linked national hospital records. Genetic susceptibility to glaucoma was calculated based on a glaucoma polygenic risk score comprising 2673 common genetic variants. Multivariable linear and logistic regression, adjusted for key sociodemographic, medical, anthropometric, and lifestyle factors, were used to model associations and gene-environment interactions.Main outcome measuresCorneal-compensated IOP, OCT derived macular retinal nerve fiber layer and ganglion cell-inner plexiform layer (GCIPL) thickness, and prevalent glaucoma.ResultsIn maximally adjusted regression models, a 1 standard deviation increase in UNa:Cr was associated with higher IOP (0.14 mmHg; 95% confidence interval [CI], 0.12-0.17; P ConclusionsUrinary sodium excretion, a biomarker of dietary intake, may represent an important modifiable risk factor for glaucoma, especially in individuals at high underlying genetic risk. These findings warrant further investigation because they may have important clinical and public health implications.Financial disclosure(s)Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.