Chronic Kidney Disease and Intraocular Pressure The Singapore Malay Eye Study Monisha E. Nongpiur, MD, 1 Tien Y. Wong, FRCSE, PhD, 1,2,3 Charumathi Sabanayagam, MD, 1,2 Su-Chi Lim, MRCP, 4 E-Shyong Tai, MRCP, 5 Tin Aung, FRCSE, PhD 1,2 Purpose: To examine the relationship of chronic kidney disease (CKD) with intraocular pressure (IOP) and glaucoma in Malay adults in Singapore. Design: Population-based, cross-sectional study. Participants: We included 3280 (78.8% response rate) Malay adults aged 40 to 79 years living in Singapore. Methods: Participants underwent a standardized interview, ocular examination, imaging, and laboratory investigations. Goldmann applanation tonometry was used to measure IOP. Glaucoma was diagnosed using the International Society of Geographic and Epidemiological Ophthalmology classification. Non-fasting serum glu- cose, glycosylated hemoglobin, and creatinine were obtained from all participants. Estimated glomerular filtration rate (eGFR) and microalbuminuria were also determined. We defined CKD as eGFR  60 ml/min/1.73 m 2 or presence of micro/macroalbuminuria, defined as urinary albumin-to-creatinine ratio 17 mg/g for men and 25 mg/g for women. Main Outcome Measures: We assessed CKD, IOP, and glaucoma. Results: The overall prevalence of CKD was 27.92% and glaucoma 4.5%. The mean (standard deviation [SD]) IOP was 15.41 (3.7) mmHg. After adjustments for age and gender, IOP was significantly higher in participants with CKD compared with those without CKD (15.8 vs 15.3 mmHg; P0.0001). The IOP was also higher with lower levels of eGFR (P0.001). These associations remained significant in separate stratified analyses of persons with and without diabetes, glaucoma, or both. In multiple linear regression models, persons with CKD had on average IOP that was 0.305 mmHg higher than that of persons without CKD. No association between CKD and glaucoma (age and gender adjusted odds ratio [OR], 0.82; 95% confidence interval [CI], 0.56 –1.20; and multivariate adjusted OR, 0.87; 95% CI, 0.58 –1.29) was found. Conclusions: Our population-based study in Malay adults showed that CKD is associated with higher IOP, independent of age, diabetes, and glaucoma status. Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article. Ophthalmology 2010;117:477– 483 © 2010 by the American Academy of Ophthalmology. With epidemiologic data from Western 1,2 and Asian 3,4 pop- ulations showing a rapid increase in the prevalence of chronic kidney disease (CKD; defined as a glomerular fil- tration rate [GFR] of 60 ml/min per 1.73 m 2 ), it is now recognized as a serious health problem worldwide. It is estimated that there are approximately 470 000 patients with end-stage renal disease in the United States as of 2004, 5 and based on earlier data, an estimated additional 8 million US adults have CKD. 1,6 Singapore is ranked third next only to the United States and Japan for the incident treatment rates of end-stage renal disease, with an expected rise in the incidence of chronic renal failure in the population. 7 Several studies have reported the potential conse- quences of chronic renal failure on the eye, such as exudative retinal detachment, cataract, band keratopathy, calcium deposits in the conjunctiva, and elevated intraocu- lar pressure (IOP). 8 –11 The precise relationship between CKD, IOP, and glaucoma, however, is unclear. Further- more, hemodialysis has been known to induce changes in the eye, 8 –11 but its effect on IOP 12–15 has yet to be com- pletely defined. Previous reports of IOP changes in patients with CKD have been limited to patients receiving hemodi- alysis either as case reports 12 or small case series 13,15 with no population-based data to date. In this context, we specifically examined the association between CKD, IOP and glaucoma in a population-based study of Malay adults from Singapore. Methods Study Population and Design The Singapore Malay Eye Study was a population-based cross- sectional epidemiological study of Malay adults aged 40 to 79 years living in Singapore. The study examined 3280 of 4168 eligible residents (78.8% response rate) living in the southwestern part of Singapore from August 2004 to July 2006. The study methodology has been described previously. 16,17 Nonparticipants 477 © 2010 by the American Academy of Ophthalmology ISSN 0161-6420/10/$–see front matter Published by Elsevier Inc. doi:10.1016/j.ophtha.2009.07.029