Diabetic retinopathy (DR) is a microvascular complication of diabetes mellitus, a metabolic disorder, but understanding of its pathophysiology remains incomplete. Meta-analysis of three population-based cross-sectional studies (2004–11) representing three major Asian ethnic groups (aged 40–80 years: Chinese, 592; Malays, 1052; Indians, 1320) was performed. A panel of 228 serum/plasma metabolites and 54 urinary metabolites were quantified using nuclear magnetic resonance (NMR) spectroscopy. Main outcomes were defined as any DR, moderate/above DR, and vision-threatening DR assessed from retinal photographs. The relationship between metabolites and DR outcomes was assessed using multivariate logistic regression models, and metabolites significant after Bonferroni correction were meta-analyzed. Among serum/plasma metabolites, lower levels of tyrosine and cholesterol esters to total lipids ratio in IDL and higher levels of creatinine were positively associated with all three outcomes of DR (all p < 0.005). Among urinary metabolites, lower levels of citrate, ethanolamine, formate, and hypoxanthine were positively associated with all three DR outcomes (all p < 0.005). Higher levels of serum/plasma 3-hydroxybutyrate and lower levels of urinary 3-hydroxyisobutyrate were associated with VTDR. Comprehensive metabolic profiling in three large Asian cohorts with DR demonstrated alterations in serum/plasma and urinary metabolites mostly related to amino acids, lipoprotein subclasses, kidney function, and glycolysis.

Cardiovascular disease (CVD) is the leading cause of death in Asians. We aimed to examine the validity and reliability of self-reported (SR) CVD in 6762 Chinese, Malay, and Indian adults aged 40–80 years who attended the baseline (November 2004) and 6-year follow-up visit (2011–2017) of a population-based cohort study in Singapore. CVD was defined based on the presence of existing (prevalent) or new onset (incident) cases of acute myocardial infarction (AMI) or stroke. The validity of SR-CVD was assessed by comparing it against diagnosed CVD using sensitivity and specificity. The reliability of SR-CVD was evaluated by calculating the percentage of positive agreement between baseline and follow-up visits. The sensitivity and specificity of SR-CVD were 62.7% and 93.8% for prevalent SR-CVD and 50.9% and 98.5% for incident SR-CVD. The negative predictive value (NPV) was 98.1% for both prevalent and incident SR-CVD. The reliability of positive self-reports between the baseline and follow-up was substantial, at 85%. The excellent specificity and NPV of SR-CVD suggest that it could serve as a valuable tool for excluding AMI and stroke. However, its moderate sensitivity suggests that positive SR-CVD reports should prompt further clinical evaluation to prevent potential false positives.

Background/Objectives: To evaluate the prevalence of eye diseases in patients with confirmed chronic kidney disease (CKD) and their referral patterns to ophthalmologists, with the aim of informing personalized screening and referral strategies. Methods: This study involved 528 CKD patients from a tertiary hospital’s outpatient renal clinics in Singapore, with CKD defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m². Retinal photographs from each dilated eye were graded for the presence of diabetic retinopathy (DR) and other eye diseases by professional graders. Patients with significant eye conditions were referred to ophthalmologists based on severity and urgency, categorized as urgent (same day or within 24 h), semi-urgent (within 1–2 weeks), fast-track (within 1–3 months), or annual referrals. Results: More than half of the CKD patients (53.7%) had some form of eye disease; 20% were diagnosed with DR, and 29% required fast-track referrals. Of the 251 patients with diabetes, 67% adhered to annual follow-ups; however, despite this regular monitoring, over half required fast-track referrals for severe eye conditions. Among the 167 non-diabetic CKD patients, nearly a third (31%) were on follow-up, with 7.8% requiring fast-track referrals. Notably, 11% of those not on follow-up also needed fast-track referrals. Seven non-diabetic and ten diabetic patients required urgent referral due to critical conditions such as pseudo-holes, impending occlusions, and disc swelling. Conclusions: These findings underscore the high prevalence and severe nature of eye diseases in CKD patients, even those who are under regular annual follow-up. Integrating systematic eye screening into CKD care supports personalized medicine by enabling early detection and tailored interventions, ultimately improving both visual and overall patient outcomes.

Background/Objectives: Cystatin C-based and combined creatinine–cystatin C estimated glomerular filtration rate (eGFR) equations improve early chronic kidney disease (CKD) detection and prediction of adverse outcomes compared to creatinine alone. However, their role in predicting microvascular complications such as diabetic retinopathy (DR) is less clear. We examined the association between diabetic kidney disease (DKD), defined using creatinine-, cystatin C-, and combined eGFR measures, as well as albuminuria, and the risk of incident DR among Asian adults in Singapore. Methods: We analysed 1135 Chinese and Indian adults with diabetes aged ≥40 years from a population-based cohort study with baseline (2007–2011) and 6-year follow-up (2013–2017) data. DR was graded from retinal photographs, and incident DR was defined as new-onset at follow-up. DKD was defined as eGFR < 60 mL/min/1.73 m² using eGFRcr, eGFRcys, combined eGFRcr-cys, and albuminuria (UACR ≥ 30 mg/g), assessed individually and jointly. Modified Poisson regression models adjusted for age, sex, ethnicity, diabetes duration, HbA1c, and systolic blood pressure were used to estimate relative risks (RRs). Results: Overall, incident DR occurred in 13.0% of participants. Among those with DKD, incidence was 18.2% (eGFRcr), 16.7% (eGFRcys), 23.7% (eGFRcr-cys), and 18.3% (albuminuria). eGFRcr-DKD (RR = 2.18, 95% CI 1.33–3.58), eGFRcys-DKD (2.38 [1.51–3.78]), and eGFRcr-cys-DKD (3.15 [1.94–5.12]) were independently associated with incident DR, whereas albuminuria alone was not. Risk increased with increasing number of markers,2.00 (1.02–3.92) by dual and 4.91 (2.50–9.65) by triple markers. Conclusions: DKD defined using multiple kidney markers, particularly combined creatinine–cystatin C, was strongly associated with incident DR. These findings support the use of multiple kidney function markers to improve risk stratification for developing DR.