Prevalence and factors associated with diabetic retinopathy in a Korean adult population: the 2008-2009 Korea National Health and Nutrition Examination Survey

Identification of Risk Factors for the Development of Diabetic Retinopathy Among Palestinian Adults With Type 2 Diabetes Mellitus: A Cross-Sectional Study

INTRODUCTION

Although risk factors linked to diabetic retinopathy (DR) among patients with Type 2 diabetes mellitus (T2DM) have been extensively studied globally, the specific determinants of these factors in relation to DR in Palestine are presently not well understood.

METHODS

This retrospective cross-sectional study included patients who underwent DR screening with a fundus camera (VersaCam a). The study included patients aged ≥18 with T2DM, excluding those with other types of diabetes or a history of malignancies. Univariable and multivariable logistic regressions were used to identify factors associated with DR.

RESULTS

A total of 1163 patients with T2DM were included in this study. Of these, 211 (18.1%) patients were classified in the DR group, 761 (65.4%) in the no DR group and 191 (16.4%) were ungradable. Among the included patients, 434 (37.3%) were male. A secondary level of education or higher and a BMI ≥30 kg/m2, compared with <25 kg/m2, were independently and inversely associated with DR, with odds ratios (ORs) of 0.46 (p < 0.001) and 0.58 (p = 0.046), respectively. A 5-year increase in the duration of T2DM correlated with 45% higher odds of having DR (p < 0.001). Patients with DR were more likely to have HbA1c >7%, be physically inactive and use insulin, with ORs of 1.63 (p = 0.02), 2.05 (p < 0.001) and 1.53 (p = 0.03), respectively. Age, gender, occupational status, hypertension and hyperlipidaemia were not independent predictors of DR (p < 0.05).

CONCLUSION

Longer duration of T2DM, HbA1c >7%, physical inactivity and insulin use were all independently associated with the presence of DR. Furthermore, a secondary or higher educational level and obesity demonstrated independent and inverse associations with the development of DR.

Smoking and diabetes: sex and gender aspects and their impact on vascular diseases

Smoking and diabetes mellitus (DM) have been identified as two major cardiovascular risk factors for many years. In the field of cardiovascular diseases, considering sex differences, or gender differences, or both has become an essential element in moving toward equitable and quality healthcare. We reviewed the impact of sex or gender on the link between smoking and DM. The risk of type 2 DM (T2DM) due to smoking has been established in both sexes at the same level. As is the case in the general population, the prevalence of smoking in those with DM is higher in men than in women, although the decrease in smoking observed in recent years is more pronounced in men than in women. Regarding chronic DM complications, smoking is an independent risk factor for all-cause mortality, as well as macrovascular and microvascular complications, in both sexes. Nevertheless, in T2DM, the burden of smoking appears to be greater in women than in men for coronary heart disease morbidity, women having a 50% higher risk of fatal coronary event. Women are more dependent to nicotine, cumulate psychosocial barriers to quitting smoking, and are more likely to gain weight, which might make it more difficult for them to quit smoking. Smoking cessation advice and treatments should take into account gender differences to improve the success and long-term maintenance of abstinence in people with and without DM. This might include interventions that address emotions and stress in women or designed to reach specific populations of men.

Elevated aqueous endothelin-1 concentrations in advanced diabetic retinopathy

Purpose

Endothelin-1 (ET-1) is a potent vasoconstrictor which seems to be involved in the pathogenesis of diabetic retinopathy (DR). However, studies on intraocular ET-1 in DR have been limited. Thus, we investigated aqueous ET-1 levels in patients with DR.

Methods

A total 85 subjects were included in this prospective study. Those were classified into three groups: advanced DR group included those with severe nonproliferative DR or proliferative DR, whereas early DR group included those with mild nonproliferative DR or moderative nonproliferative DR. Those who underwent cataract surgery and had no concomitant ocular disease were included in the control group. Aqueous humor levels of ET-1 were obtained before intravitreal bevacizumab injection (IVB) and after 1 month for the DR patients, and at the time of cataract surgery for the control group.

Results

Advanced DR group included 40 eyes (47.1%), whereas early DR group did 19 eyes (22.4%), and control group (26 eyes, 30.5%). Mean aqueous ET-1 level was 10.1±4.1 pg/mL (6.0–21.0 pg/mL) in advanced DR group, 1.9±0.7 pg/mL (0.6–2.8 pg/mL) in early DR group, and 2.1±1.0 pg/mL (0.7–3.9 pg/mL) in control group (P < 0.001). Advanced DR group was further subdivided into severe nonproliferative DR (15 eyes, 12.8%) and proliferative DR (25 eyes, 34.3%). Mean aqueous ET-1 level was 10.1±4.3 pg/mL (6.0–20.1 pg/mL) in patients with severe nonproliferative DR, and 10.0±4.0 pg/mL (6.0–21.0 pg/mL) in those with proliferative DR (P = 0.928) at baseline. Mean ET-1 level at 1 month after intravitreal injection was 2.5±1.0 pg/mL (0.3–4.8 pg/mL) in patients with severe proliferative DR and 2.9±1.7 pg/mL (1.0–7.0 pg/mL) in those with proliferative DR (P = 0.443). Mean aqueous ET-1 level was significantly reduced in both groups (P < 0.001, respectively).

Conclusion

The mean aqueous ET-1 level was significantly higher in the eyes with advanced DR than those with early DR and the control group. The mean aqueous ET-1 level was significantly reduced after intravitreal injections in the advanced DR group. Based on our results, future studies on the exact role of ET-1 in the pathogenesis of DR and future implication for intervention would be helpful for managing DR.

Risk Factors Associated With Diabetic Retinopathy: A Cross-Sectional Study Within Palestinian Patients in Northern West Bank

Risk factors associated with diabetes mellitus (DM) have been widely researched worldwide, but the determinants of these factors among diabetic retinopathy (DR) in Palestine are currently unclear. We aimed to assess the prevalence of DR among DM in Northern West Bank and identify factors associated with DR natural history. Patients with Type 2 diabetes (T2D) (n = 300, age &gt; 18 years) from a main diabetic center covering all northern provinces of Palestine were enrolled to this cross-sectional research. Demographic information including age, sex, and duration of T2D was obtained. Moreover, HbA1C, BMI, hypertension (HTN), controlled T2D, current smoking, and total cholesterol level were assessed. Potential correlations between these factors and DR diagnosed by ophthalmologist were evaluated using different tests on SPSS version 22. Prevalence of DR among our population was 30%; 47.8% of these patients showed mild non-proliferative DR (NPDR), 23.3% moderate NPDR, 16.7% severe NPDR, and 12.2% proliferative DR (PDR). Univariate logistic regression analysis showed age (p = 0.007), HTN (p = 0.022), uncontrolled T2D (p = 0.025), and duration of T2D (&lt;0.001) were mostly associated with DR while multivariate logistic regression showed duration of T2D as the major and solely risk factor for prevalence of DR (p &lt; 0.0001) and were positively correlated with severities of NPDR and being a strong predictor in the PDR (p = 0.001). We identified several important risk factors that affect DR, which could assist to develop effective strategies for metabolic disease prevention among populations in Palestine. Furthermore, our data suggest a necessity to control sugar serum levels and HTN.

Declined incidence of patients treated for vision-threatening diabetic retinopathy in South Korea: a 12-year nationwide population-based study

PURPOSE

To determine the age- and sex-specific annual incidence rates of patients treated for VTDR and the factors associated with increased treatment rates in patients with type 2 diabetes mellitus (T2DM) in South Korea.

METHODS

This was a nationwide, retrospective, 12-year, population-based study. Patients aged over 30 years who were diagnosed with T2DM between 2006 and 2017 were included in this study. We evaluated the national health claims data acquired from the Korean National Health Insurance Service database. Main outcome measures were the annual incidence rates of patients treated for VTDR and the associated risk factors.

RESULTS

The age-adjusted annual incidence rate of patients treated for VTDR significantly decreased from 10.05 per 1000 T2DM patients in 2006 to 6.11 in 2017 (β =  - 0.3192, P < 0.0001). The sex-adjusted annual incidence rate also significantly decreased in both men (β =  - 0.2861, P < 0.0001) and women (β =  - 0.3666, P < 0.0001). Cox hazard analysis showed that factors such as insulin use, young age, chronic kidney disease and male sex were significantly associated with increased rate of treatments for VTDR. In addition, the risk was lower for rural than for metropolitan residents.

CONCLUSIONS

Despite the increase in the number of T2DM patients in South Korea, the incidence rate of patients treated for VTDR decreases with early diagnosis and appropriate treatment. Therefore, it is important to detect and manage high-risk groups early to prevent visual impairment due to VTDR.

Diabetic retinopathy in the Eastern Morocco: Different stage frequencies and associated risk factors

Diabetes is a major cause of morbidity and mortality worldwide. It can affect many organs and, over time, leads to serious complications. Diabetic retinopathy (DR), a specific ocular complication of diabetes, remains the leading cause of vision loss and vision impairment in adults. This work is the first in Eastern Morocco aimed at identifying the different stages of DR and to determine their frequencies and associated risk factors. It is a case-control study conducted from December 2018 to July 2019 at the ophthalmology department of Al-Irfane Clinic (Oujda). Data were obtained from a specific questionnaire involving 244 diabetic patients (122 cases with retinopathy vs 122 controls without retinopathy). All results were analyzed by the EPI-Info software. This study shows a predominance of proliferative diabetic retinopathy (PDR) with 57.4% of cases (uncomplicated proliferative diabetic retinopathy (UPDR): 23.8%; complicated proliferative diabetic retinopathy (CPDR): 33.6%). The non-proliferative diabetic retinopathy (NPDR) represents 42.6% (minimal NPDR: 8.2%; moderate NPDR: 26.2%; severe NPDR: 8.2%). The determinants of DR were insulin therapy, high blood pressure, poor glycemic control and duration of diabetes. Regarding the chronological evolution, retinopathy precedes nephropathy. Diabetic nephropathy (DN) was present in 10.6% of cases especially in patients with PDR. In summary, the frequency of PDR was higher than that of NPDR. DR appears before DN with a high frequency of DN in patients with PDR. Good glycemic control and blood pressure control, as well as early diagnosis are the major preventive measures against DR.

The Triglyceride-Glucose Index is Associated with Diabetic Retinopathy in Chinese Patients with Type 2 Diabetes: A Hospital-Based, Nested, Case-Control Study

BACKGROUND

This study aimed to investigate the association between the triglyceride-glucose (TyG) index and diabetic retinopathy (DR) in Chinese patients with type 2 diabetes.

METHODS

In this nested case-control study, all diabetic participants were registered hospitalizations during 2012-2018, including 596 with DR as cases and three matching controls per case. DR was assessed using Early Treatment Diabetic Retinopathy Study criteria. The TyG index was calculated: Ln (fasting blood glucose [mg/dL] × fasting triglycerides [mg/dL] ÷ 2). Multivariate logistic regression, a receiver-operating characteristic (ROC) curve, linear regression models, and mediation analysis were used to explore associations.

RESULTS

The TyG index was lower in DR and decreased as its severity advanced among 2,112 subjects (P=0.005). After confounders (sex, duration of diabetes, use of antidiabetic agents, heart rate, systolic blood pressure, pulse pressure, height, weight, body-mass index, and glycated hemoglobin) had been accounted for, there were significant associations between the TyG index and any-severity DR (OR 0.83, 95% CI 0.73-0.95; P=0.006), as well as vision-threatening DR (VTDR; OR 0.53, 95% CI 0.36-0.76; P=0.001). ROC analysis indicated that the TyG index showed significant discriminatory ability in any-severity DR (area under curve [AUC] 0.534, P=0.015) and VTDR (AUC 0.624, P=0.001).

CONCLUSION

The TyG index was associated with the presence and severity of DR. Our findings suggest that the TyG index may become a useful biomarker in evaluating and following the presence of DR and VTDR.

Association between daily sunlight exposure duration and diabetic retinopathy in Korean adults with diabetes: A nationwide population-based cross-sectional study

Purpose

To investigate the association between daily sunlight exposure duration and diabetic retinopathy in Korean adults with diabetes.

Methods

This study used data from the 2008–2011 Korea National Health and Nutrition Examination Survey. Overall, 1,089 patients with diabetes aged >40 years were included. The duration of daily sunlight exposure was assessed via health interviews. Comprehensive ophthalmic evaluations, including standard retinal fundus photography after pupil dilation, were conducted. Diabetic retinopathy was graded using the modified Airlie House Classification. Multivariate logistic regression analysis was performed to analyze the association between daily sunlight exposure duration and the diagnosis of diabetic retinopathy and non-proliferative diabetic retinopathy.

Results

The risk of diabetic retinopathy was 2.66 times higher in the group with ≥5 h of daily sunlight exposure than in the group with less exposure after adjusting for risk factors such as duration of diabetes, serum hemoglobin A1c level, hypertension, and dyslipidemia (P = 0.023). Furthermore, the risk of non-proliferative diabetic retinopathy was 3.13 times higher in the group with ≥5 h of daily sunlight exposure than in the group with less exposure (P = 0.009). In patients with diabetes for <10 years, the risks of diabetic retinopathy and non-proliferative diabetic retinopathy were 4.26 and 4.82 times higher in the group with ≥5 h of daily sunlight exposure than the group with less exposure, respectively (P < 0.05).

Conclusions

This study revealed that sunlight exposure for ≥5 h a day was significantly associated with an increased risk of diabetic retinopathy and non-proliferative diabetic retinopathy in Korean patients with diabetes. The risks were significantly higher in patients with diabetes for <10 years. Therefore, reducing daily sunlight exposure could be an early preventive strategy against diabetic retinopathy in people with diabetes.

Associations between alcohol intake and diabetic retinopathy risk: a systematic review and meta-analysis

BACKGROUND

Some previous studies have reported inconsistent results on the association between alcohol intake and diabetic retinopathy (DR) risk. This study aimed to evaluate the potential effects of alcohol intake on subsequent DR risk using a meta-analytic approach.

METHODS

Three electronic databases (PubMed, EmBase, and the Cochrane library) were systematically searched for observational studies from their inception till November 2019. The pooled odds ratio (OR) with 95% confidence interval (CI) were applied for the summary effect estimate using a random-effects model.

RESULTS

A total of 15 studies (5 cohort studies, 4 case-control studies, and 6 cross-sectional studies) with 37,290 participants and 12,711 DR cases were selected for the final meta-analysis. The pooled OR indicated no significant association between alcohol intake and DR risk (OR: 0.91; 95%CI: 0.78-1.06; P = 0.225), irrespective of the studies being pooled cohort (OR: 0.95; 95%CI: 0.66-1.36; P = 0.761), case-control (OR: 0.97; 95%CI: 0.77-1.23; P = 0.818), or cross-sectional (OR: 0.86; 95%CI: 0.69-1.08; P = 0.190) ones. However, this association might have been affected by the type of diabetes mellitus and the adjusted status.

CONCLUSION

The results of this study showed that the potential impact of alcohol intake on DR risk may differ according to the type of diabetes mellitus and adjusted status. Further large-scale, prospective cohort studies should be conducted to verify the findings of this study and to evaluate DR risk in relation to the dose and type of alcohol intake.

Sex difference in the incidence of microvascular complications in patients with type 2 diabetes mellitus: a prospective cohort study

AIMS

Type 2 diabetes mellitus is a major cause of death and disability due to its long-term macro- and microvascular diseases. Although women with type 2 diabetes have more macrovascular diseases, it is unclear whether there are sex differences in the occurrence of microvascular disease. The aim of our study was to investigate sex differences in the incidence of microvascular complications in type 2 diabetes.

METHODS

Analyses were performed in the DiaGene study, a prospective cohort study for complications of type 2 diabetes, collected in the city of Eindhoven, the Netherlands (n = 1886, mean follow-up time = 6.93 years). Cox proportional hazard models adjusted for risk factors for complications (age, smoking, hypertension, dyslipidemia, HbA1c and duration of type 2 diabetes) were used to analyze the incidence of microvascular complications in men and women.

RESULTS

The incidence of microalbuminuria was significantly higher in men (HR microalbuminuria 1.64 [CI 1.21-2.24], p = 0.002). Additionally, men are more likely to develop two or three microvascular complications compared to women (OR 2.42 [CI 1.69-3.45], p < 0.001).

CONCLUSIONS

This study shows that men with type 2 diabetes are more likely to develop microvascular complications, especially microalbuminuria. Furthermore, men seem to have a higher chance of developing multiple microvascular complications. Our results highlight that men and women may not benefit to a similar extent from current treatment approaches to prevent diabetes-related microvascular diseases.

Physical activity and risk of diabetic retinopathy: a systematic review and meta-analysis

AIMS

Diabetic retinopathy (DR) is an important microvascular complication of diabetes mellitus (DM) and a leading cause of visual impairment and blindness among people of working age. Physical activity (PA) or exercise is critical and beneficial for DM patients, whereas studies evaluating the relationship between PA and DR have yielded inconsistent and inconclusive results. The American Diabetes Association's "Standards of Medical Care in Diabetes" has also pointed out the indeterminate roles of PA in DR prevention. The purpose of this systematic review and meta-analysis was to explore the association between PA and DR risk.

METHODS

Medline (accessed by PubMed), EmBase, and Cochrane Library were systematically searched for studies up to June 2018, and the reference lists of the published articles were searched manually. The association between PA and DR risk was assessed using random-effect meta-analysis.

RESULTS

Twenty-two studies were included in this meta-analysis. PA was found to have a protective association with DR [risk ratio (RR) = 0.94, 95% confidence interval (95% CI) 0.90-0.98, p = 0.005] in diabetic patients, and the impact was more pronounced on vision-threatening DR (RR = 0.89, 95% CI 0.80-0.98, p = 0.02). Sedentary behavior could increase the risk of DR (RR = 1.18, 95% CI 1.01-1.37, p = 0.04). Moderate-intensity PA was likely to have a slight protective effect (RR = 0.76, 95% CI 0.58-1.00, p = 0.05).

CONCLUSION

PA is associated with lower DR risk, and more studies should focus on the causality between them.

Association of the Serum Total Cholesterol to Triglyceride Ratio with Diabetic Retinopathy in Chinese Patients with Type 2 Diabetes: A Community-Based Study

INTRODUCTION

The relationship of total cholesterol (TC) or triglyceride (TG) to diabetic retinopathy (DR) has proven difficult to determine. In addition, there is no report of any study of the correlation between the TC/TG ratio and DR. This study was therefore undertaken to investigate the relationship between the TC/TG ratio and DR in Chinese adults with type 2 diabetes mellitus.

METHODS

A community-based study was conducted from August to October 2014 in Fengyutan, Shenyang, China. DR was assessed based on the modified Airlie House classification of DR. Multivariable logistic regression models were used to evaluate the association between the TC/TG ratio and the presence of DR.

RESULTS

Among the 420 diabetic participants in the study (157 men; mean (SD) age 61.7 (10.0) years), 76 (18.1%) presented with DR. When the TC/TG ratio was analyzed categorically, participants with T2DM in tertile 2 (i.e., TC/TG 2.91-4.00) were more likely (OR 2.01; 95% CI 1.01-3.99) to suffer from DR than patients in tertile 1 (i.e., TC/TG < 2.91) in multivariable models. Similarly, participants in tertile 3 (TC/TG > 4.00) were more likely (OR 2.59; 95% CI 1.11-3.14; P = 0.011) to suffer from DR than patients in tertile 1. This association persisted when the TC/TG ratio was analyzed continuously (P = 0.014).

CONCLUSION

We found a novel positive association between TC/TG ratio and presence of DR in Chinese individuals with T2DM. Although longitudinal data are needed, this finding contributes to the accumulating evidence that a high TC/TG ratio may be implicated in DR.

Review of the literature examining the association between physical activity and retinopathy

The main aim of this review was to evaluate the association between physical activity and retinopathy. Secondary aims included evaluating the association between sedentary behavior and retinopathy, and evaluating the association between physical activity/sedentary behavior on health outcomes among patients with existing retinopathy. Twenty-one articles met our criteria for inclusion in this review. Among the 19 studies evaluating the main aim (physical activity and retinopathy), 53% (n = 10/19) demonstrated evidence of a favorable (inverse) association between physical activity and retinopathy, 42% (n = 8/19) reported a null association physical activity and retinopathy, and 5% (n = 1/19) presented evidence for a detrimental association between physical activity and retinopathy. Regarding the secondary aims, one study demonstrated a detrimental association between sedentary behavior and retinopathy. Similarly, one study demonstrated that physical activity was protective against early mortality among those with mild retinopathy. This review identifies an 'indeterminate' association between physical activity and retinopathy. Too few studies evaluated the association between sedentary behavior and retinopathy or the effects of physical activity on health outcomes among those with existing retinopathy.

Nicotine promotes blood retinal barrier damage in a model of human diabetic macular edema

More than 1 billion world's population actively smokes tobacco containing the bioactive component nicotine (NT). The biological role of this molecule is mediated through the activation of nicotinic cholinergic receptors, widely distributed in various human tissues including retinal pigmented epithelium. The long-term assumption of NT contributes to several diseases development such as diabetic retinopathy. The major complication of this pathology is the diabetic macular edema (DME), characterized by macular area thinning and blood-retinal barrier (BRB) breakdown. Retinal hyperglycemic/hypoxic microenvironment represents one of the main factors favoring DME progression by eliciting the hypoxia-inducible factors (HIFs) expression. The latter induce new vessels formation by stimulating cellular secretion of vascular endothelial growth factor (VEGF). The etiology of DME is multifactorial, but little is known about the risk factors linked to cigarette smoking, in particular to nicotine's contribution. In the present study, we have investigated the NT role in a model, in vitro, of DME, by evaluating its effect on outer BRB permeability and HIFs/VEGF expression following exposure to hyperglycemic/hypoxic insult. Our results have demonstrated that this compound alters outer BRB integrity exposed to high glucose and low oxygen pressure microenvironment by upregulating HIF-1α/HIF-2α, VEGF expression and ERK1/2 phosphorylation. These data have suggested that NT may play a negative role in active smokers affected by DME.

Diabetic care initiatives to prevent blindness from diabetic retinopathy in India

It is estimated that 65 million (17%) of 382 million persons with diabetes mellitus (DM) globally reside in India. While globally 35% persons with DM have diabetic retinopathy (DR), this proportion is reportedly lower in India, other countries in South Asia and China. We reviewed published data from 2008 onwards from PubMed, which ascertained DR in population-based representative samples. We also reviewed the risk factors for DR, on awareness regarding eye complications and on accessing an eye examination. Thirteen research studies have reported on the prevalence of DR among persons with DM; this prevalence was lower than the global level in China, India, and Nepal. Eleven studies reported DR risk factors association. The duration of diabetes and level of glycemic control were universally acknowledged DR risk factors. We identified 7 studies in the Asia region that researched the level of awareness about diabetes eye complications and the practice of accessing an eye examination. Excepting 1 study in China, others reported a significant proportion being aware that diabetes leads to eye complications. But the awareness was not translated into a positive practice-most studies reported only 20-50% of the persons with diabetes actually having had their eyes examined. The present review highlights the observation that the risk factors for DR need an integrated diabetic care pathway where the eye care team has to work in close collaboration and partnership with a diabetic care team has to reduce the risk of blindness from DR.

Risk factors for diabetic retinopathy: a case-control study

BACKGROUND

Diabetic retinopathy (DR) is the major cause of blindness among working age adults. The aim of the study was to investigate risk factors for development of DR.

METHODS

A case-control study was performed based on data from 240 individuals (80 cases and 160 controls) attending the Outpatient Specialty Clinic of the University of South Santa Catarina (UNISUL), between Mar/2010 and May/2014. Data collection occurred through review of medical charts for presence or absence of DR, determined by an ophthalmologist. Study protocol included demographic characteristics, metabolic control, diabetes mellitus (DM) profile and comorbidities. Statistical analysis used Chi square test for qualitative variables and multivariate logistic regression analysis to select independent variables (SPSS®18.0 software). Odds ratio (OR) was used as measure of association. The study was approved by research ethics committee of UNISUL.

RESULTS

Mean age of group case was 59.5 years with a slight female predominance. Gender, age, body mass index were not associated with outcome. Individuals with poor glycemic control were more likely to DR (OR 3.83; 95 % CI 1.57-9.37). It was observed a positive relationship between duration of DM and DR, with higher chances in 11-15 years of disease (OR 7.52, 95 % CI 3.03-18.68) and >15 years (OR 9.01, 95 % CI 3.58-22.66). Regarding comorbidities, only diabetic nephropathy showed higher chance for DR (OR 3.32; 95 % CI 1.62-6.79).

CONCLUSIONS

Diabetic patients after 10 years of disease with poor glycemic control and nephropathy have a higher chance of DR.

An Overview of Ophthalmologic Survey Methodology in the 2008-2015 Korean National Health and Nutrition Examination Surveys

The Korea National Health and Nutrition Examination Survey (KNHANES) is a national program designed to assess the health and nutritional status of the noninstitutionalized population of South Korea. The KNHANES was initiated in 1998 and has been conducted annually since 2007. Starting in the latter half of 2008, ophthalmologic examinations were included in the survey in order to investigate the prevalence and risk factors of common eye diseases such as visual impairment, refractive errors, strabismus, blepharoptosis, cataract, pterygium, diabetic retinopathy, age-related macular degeneration, glaucoma, dry eye disease, and color vision deficiency. The measurements included in the ophthalmic questionnaire and examination methods were modified in the KNHANES IV, V, and VI. In this article, we provide detailed information about the methodology of the ophthalmic examinations in KNHANES in order to aid in further investigations related to major eye diseases in South Korea.

Moderate consumption of white and fortified wine is associated with reduced odds of diabetic retinopathy

AIM

To explore the association between alcohol consumption and the severity of diabetic retinopathy (DR).

METHODS

In this cross-sectional study, patients with type 2 diabetes answered questions on consumption of low and full-strength beer, white wine/champagne, red wine, fortified wines, and spirits. Never, moderate and high consumption of each alcoholic beverage, and overall alcoholic beverage consumption, were defined as <1, 1-14 and >14 standard drinks/week, respectively. DR was categorized into none; non vision-threatening DR (VTDR) and VTDR. Multivariable logistic regression determined the associations between alcohol consumption and DR.

RESULTS

Of the 395 participants (mean age±SD [standard deviation] 65.9±10.4years; males=253), 188 (47.6%) consumed alcohol and 235 (59.5%) had any DR. Compared to no alcohol consumption, moderate alcohol consumption (overall) was significantly associated with reduced odds of any DR (OR=0.47, 95% CI [confidence interval] 0.26-0.85). Moderate consumption of white wine/champagne or fortified wine was also associated with reduced odds of any DR (OR=0.48, 95% CI 0.25-0.91, and OR=0.15, 95% CI 0.04-0.62, respectively). Similar results were observed for non-VTDR and VTDR.

CONCLUSIONS

The amount and type of alcohol are associated with risk of DR in patients with type 2 diabetes. A longitudinal study is needed to assess the protective effect of alcohol consumption and DR.

Diabetic retinopathy - ocular complications of diabetes mellitus

In industrialized nations diabetic retinopathy is the most frequent microvascular complication of diabetes mellitus and the most common cause of blindness in the working-age population. In the next 15 years, the number of patients suffering from diabetes mellitus is expected to increase significantly. By the year 2030, about 440 million people in the age-group 20-79 years are estimated to be suffering from diabetes mellitus worldwide (prevalence 7.7%), while in 2010 there were 285 million people with diabetes mellitus (prevalence 6.4%). This accounts for an increase in patients with diabetes in industrialized nations by 20% and in developing countries by 69% until the year 2030. Due to the expected rise in diabetic patients, the need for ophthalmic care of patients (i.e., exams and treatments) will also increase and represents a challenge for eye-care providers. Development of optimized screening programs, which respect available resources of the ophthalmic infrastructure, will become even more important. Main reasons for loss of vision in patients with diabetes mellitus are diabetic macular edema and proliferative diabetic retinopathy. Incidence or progression of these potentially blinding complications can be greatly reduced by adequate control of blood glucose and blood pressure levels. Additionally, regular ophthalmic exams are mandatory for detecting ocular complications and initiating treatments such as laser photocoagulation in case of clinical significant diabetic macular edema or early proliferative diabetic retinopathy. In this way, the risk of blindness can considerably be reduced. In advanced stages of diabetic retinopathy, pars-plana vitrectomy is performed to treat vitreous hemorrhage and tractional retinal detachment. In recent years, the advent of intravitreal medication has improved therapeutic options for patients with advanced diabetic macular edema.

Prevalence and risk factors of diabetes and diabetic retinopathy in Liaoning province, China: a population-based cross-sectional study

Aim

To evaluate the prevalence and risk factors of diabetes and diabetic retinopathy (DR) in northeast area of China with a population-based study.

Methods

A population of 3173 (aged from 20 to 80 years old) was stratified by geographical location and age in Liaoning province, China. Prediabetes and diabetes were diagnosed according to the guideline of American Diabetes Association. Retinal photographs were obtained by using digital non-mydriatic camera for the presence and grading of DR according to the modified ETDRS Airlie house classification. Blood samples and comprehensive questionnaires were obtained for evaluation of laboratory results and risk factors.

Results

The prevalence of prediabetes and diabetes was 20.7% and 10.4%, respectively. Among diabetes patients, DR prevalence was 11.9%. Age, obesity, total cholesterol, triglycerides, hypertension, living in rural areas and diabetes family history are all risk factors for prediabetes and diabetes. Waist-to-hip circumference rate served as a better obesity index to estimate diabetes risk compared with body mass index and waist circumference. Among all risk factors that we investigated, only the length of diabetes history was associated with the incidence of DR. However, DR prevalence in the newly discovered patients in rural areas was significantly higher than that in urban areas.

Conclusion

According to this study, 1 in 10 people has diabetes, 2 in 10 people have prediabetes, and 1 in 10 diabetics has DR in Liaoning province. In rural areas, diabetes was poorly recognized with limited medical resources, which probably resulted in more diabetes patient at a high risk of DR.