Diabetic Retinopathy and Chronic Kidney Disease: Associations and Comorbidities in a Large Diabetic Population - The Tongren Health Care Study.

INTRODUCTION: The aim of the study was to investigate associations between diabetic retinopathy (DR) and chronic kidney disease (CKD) in patients with type 2 diabetes (TD2). METHODS: The participants of the cross-sectional, community-based Tongren Health Care Study underwent a detailed medical and ophthalmological examination. We defined TD2 by a fasting plasma glucose concentration of ≥7.0 mmol/L or a medical history. CKD was classified as either reduced estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 mm2 or presence of albuminuria. DR was assessed using color fundus photographs. RESULTS: Out of 62,217 participants of the Tongren Health Care Study, 5,103 (8.2%) patients had TD2. The prevalence of DR was 12.8% (95% CI, 11.8%, 13.7%), CKD was 13.3% (95% CI, 12.4%, 14.3%), and the subtypes of CKD including reduced eGFR and albuminuria was 4.6% (95% CI, 4.2%, 5.1%) and 10.1% (95% CI, 9.3%, 10.9%), respectively. DR was detectable in 21.0% of the patients with CKD, while CKD was present in 20.9% of the DR patients. Higher DR prevalence was associated with higher prevalence of albuminuria and reduced eGFR (both p < 0.05). Factors independently associated with the presence of CKD instead of DR were older age (p < 0.001, OR = 1.05), a higher body mass index (p < 0.001, OR = 1.14), a higher serum concentration of triglycerides (p < 0.001, OR = 1.26), and a lower blood glucose (p < 0.001, OR = 0.93). Having hypertension was additionally associated with the presence of reduced eGFR as compared with DR (p = 0.005, OR = 4.47). CONCLUSIONS: TD2 patients of older age and with higher body mass index, hypertension, and dyslipidemia had a higher probability of being affected by CKD rather than DR, while those with a higher blood glucose level were more prone to DR than CKD.

Is Kidney Function Associated with Age-Related Macular Degeneration?: Findings from the Asian Eye Epidemiology Consortium.

PURPOSE: Chronic kidney disease (CKD) may elevate susceptibility to age-related macular degeneration (AMD) because of shared risk factors, pathogenic mechanisms, and genetic polymorphisms. Given the inconclusive findings in prior studies, we investigated this association using extensive datasets in the Asian Eye Epidemiology Consortium. DESIGN: Cross-sectional study. PARTICIPANTS: Fifty-one thousand two hundred fifty-three participants from 10 distinct population-based Asian studies. METHODS: Age-related macular degeneration was defined using the Wisconsin Age-Related Maculopathy Grading System, the International Age-Related Maculopathy Epidemiological Study Group Classification, or the Beckman Clinical Classification. Chronic kidney disease was defined as estimated glomerular filtration rate (eGFR) of less than 60 ml/min per 1.73 m2. A pooled analysis using individual-level participant data was performed to examine the associations between CKD and eGFR with AMD (early and late), adjusting for age, sex, hypertension, diabetes, body mass index, smoking status, total cholesterol, and study groups. MAIN OUTCOME MEASURES: Odds ratio (OR) of early and late AMD. RESULTS: Among 51 253 participants (mean age, 54.1 ± 14.5 years), 5079 had CKD (9.9%). The prevalence of early AMD was 9.0%, and that of late AMD was 0.71%. After adjusting for confounders, individuals with CKD were associated with higher odds of late AMD (OR, 1.46; 95% confidence interval [CI], 1.11-1.93; P = 0.008). Similarly, poorer kidney function (per 10-unit eGFR decrease) was associated with late AMD (OR, 1.12; 95% CI, 1.05-1.19; P = 0.001). Nevertheless, CKD and eGFR were not associated significantly with early AMD (all P ≥ 0.149). CONCLUSIONS: Pooled analysis from 10 distinct Asian population-based studies revealed that CKD and compromised kidney function are associated significantly with late AMD. This finding further underscores the importance of ocular examinations in patients with CKD. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Macular outer nuclear layer, ellipsoid zone and outer photoreceptor segment band thickness, axial length and other determinants.

The study aims to assess the thickness of the retinal outer nuclear layer (ONL), ellipsoid zone (EZ) and photoreceptor outer segment (POS) band in various macular regions and its associations with axial length and other parameters. Participants of the Beijing Eye Study 2011 underwent a series of examinations including spectral-domain optical coherence tomography of the macula. The current study included 2213 participants without retinal or optic nerve diseases (age: 61.7 ± 8.4 years; range 50-93 years); axial length: 23.15 ± 0.95 mm; range 18.96-29.15 mm). The ONL (fovea: 98.9 ± 8.8 µm), EZ (fovea: 24.1 ± 0.5 µm) and POS band (fovea: 24.3 ± 3.5 µm) were the thickest (P < 0.001) in the fovea (defined as the thinnest central point), followed by the temporal inner, nasal inner, inferior inner, superior inner, inferior outer, temporal outer, nasal outer, and superior outer region. In multivariable analysis, a thicker retinal ONL was associated (correlation coefficient r: 0.40) with shorter axial length (beta: - 0.14; P < 0.001) and shorter disc-fovea distance (beta: - 0.10; P = 0.001), after adjusting for younger age (beta: - 0.26; P < 0.001), male sex (beta: 0.24; P < 0.001), lower serum cholesterol concentration (beta: - 0.05; P = 0.04), and thicker subfoveal choroidal thickness (beta: 0.08; P < 0.001). The POS thickness increased with shorter axial length (beta: - 0.06; P < 0.001) and shorter optic disc-fovea distance (beta: - 0.05; P = 0.03), after adjusting for younger age (beta: - 0.34; P < 0.001), male sex (beta: 0.15; P < 0.001), and thicker subfoveal choroidal thickness (beta: 0.24; P < 0.001). As a conclusion, the photoreceptor ONL, EZ and POS band vary in thickness between different macular regions and differ in their correlations with axial length, disc-fovea distance, age, sex, and subfoveal choroidal thickness. The ONL thickness decrease with longer axial length and longer disc-fovea distance may point to an axial elongation-associated retinal stretching in the macula.

Parapapillary gamma zone associated with increased peripapillary scleral bowing: the Beijing Eye Study 2011.

AIMS: To investigate the association between the backward configuration of the peripapillary sclera (PPS), measured as PPS angle (PPSA), and presence and extent of parapapillary gamma zone. METHODS: Out of the population-based Beijing Eye Study 2011, we randomly selected individuals free of optic nerve and retinal diseases. With Spectralis optical coherence tomography, we measured gamma zone (zone free of Bruch's membrane (BM)) and determined the PPSA, defined as the angle between the anterior scleral surface lines from both sides of the optic nerve head (ONH). RESULTS: The study included 678 individuals with age of 59.5±7.6 years (range: 50-90) and axial length of 23.5±1.3 mm (20.9-29.2). Gamma zone was more prevalent in eyes with larger PPSA (p=0.006) after adjustment for axial length (p<0.001) and BM opening area (p<0.001). Gamma zone width was positively associated with PPSA, axial length and BM opening area (all p<0.001) in multivariable analysis. Circular gamma zone was accompanied with larger PPSA as compared with focal gamma zone (19.9°±7.2° vs 6.3°±5.3°, p<0.001). Focal temporal gamma and focal inferior gamma had similar mean PPSA (p=0.69). However, the horizontal PPSA was significantly larger than the vertical PPSA in inferior gamma (6.9°±6.3° vs 4.7°±6.6°; p=0.005), while they were comparable in temporal gamma (6.1°±5.8° vs 6.3°±6.4°; p=0.073). CONCLUSIONS: A more backward bowing of the PPS was linearly and spatially associated with the presence, size and extent of gamma zone. It suggested that the BM and the sclera were closely related in participating the biomechanical behaviour of the ONH.

Arterial hypertension and retinal layer thickness: the Beijing Eye Study.

PURPOSE: To investigate relationships between blood pressure and the thickness of single retinal layers in the macula. METHODS: Participants of the population-based Beijing Eye Study, free of retinal or optic nerve disease, underwent medical and ophthalmological examinations including optical coherence tomographic examination of the macula. Applying a multiple-surface segmentation solution, we automatically segmented the retina into its various layers. RESULTS: The study included 2237 participants (mean age 61.8±8.4 years, range 50-93 years). Mean thicknesses of the retinal nerve fibre layer (RNFL), ganglion cell layer (GCL), inner plexiform layer, inner nuclear layer (INL), outer plexiform layer, outer nuclear layer/external limiting membrane, ellipsoid zone, photoreceptor outer segments (POS) and retinal pigment epithelium-Bruch membrane were 31.1±2.3 µm, 39.7±3.5 µm, 38.4±3.3 µm, 34.8±2.0 µm, 28.1±3.0 µm, 79.2±7.3 µm, 22.9±0.6 µm, 19.2±3.3 µm and 20.7±1.4 µm, respectively. In multivariable analysis, higher systolic blood pressure (SBP) and diastolic blood pressure (DBP) were associated with thinner GCL and thicker INL, after adjusting for age, sex and axial length (all p<0.0056). Higher SBP was additionally associated with thinner POS and higher DBP with thinner RNFL. For an elevation of SBP/DBP by 10 mm Hg, the RNFL, GCL, INL and POS changed by 2.0, 3.0, 1.5 and 2.0 µm, respectively. CONCLUSIONS: Thickness of RNFL, GCL and POS was inversely and INL thickness was positively associated with higher blood pressure, while the thickness of the other retinal layers was not significantly correlated with blood pressure. The findings may be helpful for refinement of the morphometric detection of retinal diseases.

GUNN's DOTS AS INDICATORS OF RENAL FUNCTION, FINDINGS FROM THE TONGREN HEALTH CARE STUDY.

PURPOSE: To investigate the prevalence of Gunn's dots (GDs) and associated systemic factors in adult Chinese. METHODS: A cross-sectional study enrolling participants older than 45 years from a community-based study. Gunn's dots were evaluated using fundus photography, and associated systemic factors were analyzed. Patients with any retinal or optic neuropathy were excluded. RESULTS: The study included 4,118 participants (mean age: 58.3 ± 9.9 years; male: 1,699/41.3%). Gunn's dots were found in 931 participants, with a prevalence of 22.6 ± 0.8% (95% confidence interval [CI]: 21.3-23.9). Systemic factors associated with a higher GD prevalence were younger age (odds ratio [OR]: 0.92; 95% CI: 0.91-0.93; P < 0.001), higher estimated glomerular filtration rate (eGFR) (OR: 1.01; 95% CI: 1.001-1.02; P = 0.022), and higher serum concentration of triglycerides (OR: 1.08; 95% CI: 1.004-1.16; P = 0.040). The GD prevalence was 3.5 (OR = 3.46; 95% CI: 1.06-11.35) and 4.4 (OR = 4.37; 95% CI: 1.27-15.09) times greater for participants with an eGFR of ≥90 mL/minute/1.73 m2 and an eGFR of ≥100 mL/minute/1.73 m2, respectively, as compared with participants with an eGFR of <60 mL/minute/1.73 m2. CONCLUSION: The GD prevalence (mean: 22.6%) was associated with younger age, higher eGFR, and higher serum triglyceride concentrations. The presence of GDs may serve as indicators of healthy renal function.

Peripheral Monocyte Count and Age-Related Macular Degeneration. The Tongren Health Care Study.

PURPOSE: To assess potential associations between the prevalence of age-related macular degeneration (AMD) and systemic parameters in a Chinese population. DESIGN: Cross-sectional study. METHODS: The Tongren Health Care Study included individuals attending regular health care check-up examinations in the Beijing Tongren Hospital from 2017 to 2019. Detailed medical examinations and ophthalmic examinations were applied, including fundus photography. AMD was evaluated according to the Beckman Initiative guidelines. RESULTS: The study included 7,719 participants (mean age: 60.5 ± 8.1 years; range: 50-97 years). The prevalence of any, early, intermediate, and late AMD was 1,607 of 7,719 (20.8%; 95% confidence interval [CI]: 20.1%, 21.9%), 832 of 7,719 (10.8%; 95% CI: 10.1%, 11.5%), 733 of 7,719 (9.5%; 95% CI: 8.9%, 10.2%), and 42 of 7,719 (0.50%; 95% CI: 0.40%, 0.70%), respectively. In multivariate analysis, the prevalence of any AMD increased with higher blood monocyte count (odds ratio [OR]:3.49; 95% CI: 2.26, 5.38; P < .001), after adjusting for older age (OR: 1.06; 95% CI: 1.05, 1.07; P < .001), higher serum concentration of calcium (OR: 2.52; 95% CI: 1.32, 4.84; P = .005), high-density lipoproteins (OR: 1.39; 95% CI: 1.19, 1.61; P < .001), and lower lipoprotein a (OR: 0.99; 95% CI: 0.98, 0.99; P = .02). Similar findings were obtained for the prevalence of intermediate and late AMD combined. The association between higher monocyte count and higher AMD prevalence showed the highest odds ratio for the age group of 50-59 years (any AMD: OR: 4.35, P < .001; intermediate and late AMD: OR: 6.14, P < .001). Individuals with a monocyte count of ≥0.5 × 109/L as compared to participants with a monocyte of 0.1-0.4 × 109/L had a 1.45-fold increased risk for any AMD (OR: 1.45; 95% CI: 1.27, 1.64; P < .001) and 1.58 fold increase risk for intermediate/late AMD (OR: 1.58; 95% CI: 1.33, 1.87; P < .001). CONCLUSION: A higher prevalence of early AMD, intermediate AMD, late AMD, and any AMD was associated with a higher peripheral monocyte count. In agreement with previous studies, the observation suggests monocytes playing a role in the pathogenesis of AMD.

Serum Sodium Concentration and Increased Risk for Primary Epiretinal Membrane.

Aims: To examine the prevalence of primary epiretinal membranes (ERMs) and associated systemic factors. Methods: The cross-sectional, community-based Tongren Health Care Study enrolled participants who received regular health examinations in the Beijing Tongren Hospital from 2017 to 2019. Using fundus photographs, retinal specialists assessed the presence of ERMs and their systemic associations. Results: Primary ERMs were detected in 841/22820 individuals, with a prevalence of 3.7% [95% confidence intervals (CI): 3.4-3.9%] in the total study population (mean age: 44.5 ± 13.8 years) and 6.5% (95% CI: 6.1-7.0%) in individuals aged 40+ years. In multivariable analysis, a higher ERMs prevalence was associated with older age [odds ratio (OR): 1.10; P < 0.001], higher serum cholesterol concentration (OR: 1.14; P = 0.003) and higher serum sodium concentration (SSC) (OR: 1.12; P < 0.001). In women, a higher SSC, even within the normal range, was associated with an increased risk of ERMs (OR: 1.19; P < 0.001). Female participants with an SSC of 144-145mmol/L as compared with those with an SSC of 135-137 mmol/L had a 5-fold increased odds of having ERMs (All women: OR: 5.33; P < 0.001; Women aged 40+years: OR: 4.63; P < 0.001). Conclusion: Besides older age and higher serum cholesterol concentration, a higher SSC, even if within the normal range, was independently associated with a higher ERM prevalence in women.

A pilot study of the precision of digital intraocular pressure measurement during vitrectomy.

AIM: To evaluate the precision of digital intraocular pressure (IOP) measurement in silicone oil (SO) filled eyes during vitrectomy. METHODS: This is a retrospective, single-blind study. Patients who were diagnosed with retinal detachment and scheduled for vitrectomy with SO injection were consecutively enrolled. During the vitrectomy, IOP was digitally measured and then by a rebound tonometer (IcarePRO). The rebound tonometer readings were masked to the surgeons. The digitally measured IOP and that of rebound tonometer were compared, and the inter-methods agreement was assessed. The absolute deviation in IOP values between these two methods (ΔIOP) was also calculated, and correlations between ΔIOP and refractive status, lens status and levels of surgeons' experience were analyzed. RESULTS: A total of 131 patients (131 eyes) were recruited, with a mean age of 51.0±16.1y. There was no significant difference in IOPs between digital measurement and the rebound tonometer (15.6±4.3 vs 15.7±5.1 mm Hg; t=0.406, P=0.686). Intraclass correlation coefficients (ICC) analysis indicated a strong correlation between these two measurements (ICC=0.830, P<0.001). The mean ΔIOP was 2.0±1.9 mm Hg (range: 0-12.8 mm Hg), with 98 eyes (74.8%) had the ΔIOP within 3 mm Hg. ΔIOP was found to be negatively correlated with levels of surgeons' experience (r=-0.183; P=0.037), but not with the refractive status or lens status of the patients (both P>0.05). CONCLUSION: For experienced surgeons, the digital IOP measurement may be an acceptable technique for IOP measurement in SO filled eyes during vitrectomy. However, its use by inexperienced surgeons should be taken with caution.