Development of diabetic retinopathy and its associated risk factors in type 2 diabetic patients in Osaka district, Japan: a long-term prospective study

Recognition of ophthalmology consultation and fundus examination among individuals with diabetes in Japan: A cross-sectional study using claims-questionnaire linked data

AIMS

This study aimed to assess the relationship between individuals' recognition of ophthalmology consultation recommendations, their knowledge of the recommended frequency of diabetic retinopathy screening, and the likelihood of undergoing fundus examinations.

MATERIALS AND METHODS

This cross-sectional secondary analysis linked claims and health checkup data to a questionnaire survey. Questionnaires were distributed to randomly sampled National Health Insurance beneficiaries in Tsukuba City, using data from claims and health checkups. Weighting was applied based on sample extraction and response rates. We calculated the proportions of fundus examinations and knowledge of screening frequency according to the recognition of ophthalmology consultation recommendations. The association between visits to medical facilities with diabetes specialists and diabetic retinopathy screening was also examined.

RESULTS

Among 290 participants, 47.6% recognized ophthalmology consultation recommendations. Those who recognized these recommendations had better knowledge of the screening frequency (93.4% vs. 49.6%) and were more likely to undergo fundus examinations (72.9% vs. 30.1%; adjusted risk ratio 2.36; 95% CI, 1.65-3.38). Participants who visited medical facilities with diabetes specialists were more likely to recognize recommendations, have knowledge of screening frequency, and undergo fundus examinations.

CONCLUSIONS

Recognition of ophthalmology consultation recommendations was associated with better knowledge of screening frequency and higher participation in fundus examinations. Increasing awareness through healthcare provider recommendations may improve diabetic retinopathy screening rates, highlighting the need for targeted interventions to promote eye care among individuals with diabetes.

Hyperglycemia Augments Endothelin-1-Induced Constriction of Human Retinal Venules

Purpose

Endothelin-1 (ET-1) is a potent vasoactive factor implicated in development of diabetic retinopathy, which is commonly associated with retinal edema and hyperglycemia. Although the vasomotor activity of venules contributes to the regulation of tissue fluid homeostasis, responses of human retinal venules to ET-1 under euglycemia and hyperglycemia remain unknown and the ET-1 receptor subtype corresponding to vasomotor function has not been determined. Herein, we addressed these issues by examining the reactivity of isolated human retinal venules to ET-1, and results from porcine retinal venules were compared.

Methods

Retinal tissues were obtained from patients undergoing enucleation. Human and porcine retinal venules were isolated and pressurized to assess diameter changes in response to ET-1 after exposure to 5 mM control glucose or 25 mM high glucose for 2 hours.

Results

Both human and porcine retinal venules exposed to control glucose developed similar basal tone and constricted comparably to ET-1 in a concentration-dependent manner. ET-1–induced constrictions of human and porcine retinal venules were abolished by ET_A receptor antagonist BQ123. During high glucose exposure, basal tone of human and porcine retinal venules was unaltered but ET-1–induced vasoconstrictions were enhanced.

Conclusions

ET-1 elicits comparable constriction of human and porcine retinal venules by activation of ET_A receptors. In vitro hyperglycemia augments human and porcine retinal venular responses to ET-1.

Translational Relevance

Similarities in vasoconstriction to ET-1 between human and porcine retinal venules support the latter as an effective model of the human retinal microcirculation to help identify vascular targets for the treatment of retinal complications in patients with diabetes.

Relationship between HbA1c and risk of retinal hemorrhage in the Japanese general population: The Circulatory Risk in Communities Study (CIRCS)

AIMS

Retinal hemorrhage is an important finding on fundus photography. Diabetes mellitus is a cause of retinal hemorrhage, although other causes exist. We sought to better characterize the association between retinal hemorrhage and HbA1c in the Japanese population.

METHODS

We conducted a prospective study of 11,644 Japanese men and women aged 30-78years between 2001 and 2011. Fundus photography was performed as part of an annual cardiovascular disease risk survey. HbA1c was determined by the latex coagulation method throughout the study. We used logistic regression models to examine the association between HbA1c and the risk of retinal hemorrhage and diabetic retinal hemorrhage.

RESULTS

During a median follow-up period of 4.6years, 509 retinal hemorrhages, including 96 diabetic retinal hemorrhages, were diagnosed. HbA1c was positively associated with the risk of retinal hemorrhage and diabetic retinal hemorrhage among subjects not taking medication for diabetes mellitus at baseline, but not among subjects who were taking medication at baseline.

CONCLUSIONS

HbA1c was positively associated with the risk of retinal hemorrhage and the subcategory of diabetic retinal hemorrhage among subjects not taking medication for diabetes mellitus at baseline. The association was evident for diabetic retinal hemorrhage, compared with retinal hemorrhage.

High HbA1c level was the most important factor associated with prevalence of diabetic retinopathy in Taiwanese type II diabetic patients with a fixed duration

BACKGROUND

To identify the prevalence and related risk factors for diabetic retinopathy (DR) in non-insulin dependent diabetes in Taiwan.

METHODS

A retrospective review of type II diabetic patients in the Diabetes Shared Care System database of our Hospital enrolled from 2002 to 2009. A retinopathy severity score was assigned according to fundus examination by indirect ophthalmoscopy or binocular biomicroscopy.

RESULTS

Data was collected on 901 subjects, 497 males and 404 females. Of these, 230 (25.53 %) had DR at enrolment. Compared with patients without DR, those with DR were more likely to be female (p = 0.03) or have higher HbA1c (p < 0.001), longer duration of diabetes (p < 0.001), hypertension (p < 0.001), higher systolic blood pressure (p < 0.001), higher diastolic blood pressure (p = 0.05), as well as impaired renal function (p = 0.001). In subgroup analysis stratified by diabetes duration, HbA1c was the most consistent independent risk factor associated to the prevalence of DR. Higher systolic blood pressure and female sex were significantly independent risk factors only in patients with a duration of diabetes < 4 years. On the contrary, old onset age showed a protective effect against DR only in those with a disease duration > 8 years.

CONCLUSIONS

High HbA1c level was the most important factor associated with prevalence of DR in Taiwanese type II DM patients with a fixed duration.

Incidence and progression of diabetic retinopathy in Japanese adults with type 2 diabetes: 8 year follow-up study of the Japan Diabetes Complications Study (JDCS)

AIMS/HYPOTHESIS

The aim of this study was to determine the incidence and progression rates of diabetic retinopathy and their associations in Japanese individuals with type 2 diabetes.

METHODS

This is a part of the Japan Diabetic Complications Study (JDCS), a multi-centred randomised trial of type 2 diabetes patients aged 40-70 years with an 8 year follow-up. There were 1,221 patients without diabetic retinopathy at baseline; incidence of diabetic retinopathy was defined as the development of any diabetic retinopathy. There were 410 patients with mild non-proliferative diabetic retinopathy at baseline; progression of diabetic retinopathy was defined as the development of severe non-proliferative diabetic retinopathy or proliferative diabetic retinopathy. We used multivariate proportional Cox hazard models, and generalised additive models were also applied to identify potential threshold effect.

RESULTS

The incidence and progression rate of diabetic retinopathy was 38.3/1,000 person-years and 21.1/1,000 person-years, respectively. Higher HbA(1c) (adjusted HR [aHR] per 1% [10.9 mmol/mol] 1.36 [95% CI 1.28-1.45]), longer duration of diabetes (aHR per 5 year period 1.26 [95% CI 1.17-1.35]), higher systolic blood pressure (aHR per +10 mmHg 1.01 [95% CI 1.00-1.02]) and higher body mass index (aHR per 1 kg/m(2) 1.05 [95% CI 1.00-1.09]) were associated with incident diabetic retinopathy. The association between HbA(1c) and incident diabetic retinopathy was linear; the association with duration of diabetes increased rapidly between 5 and 10 years. Higher HbA(1c) was also associated with progression of diabetic retinopathy (aHR per 1% [10.9 mmol/mol] 1.66 [95% CI 1.41-1.96]).

CONCLUSIONS

Observed incidence and progression rates of diabetic retinopathy seemed lower than that in western populations. HbA(1c) was the only factor associated with both incidence and progression of diabetic retinopathy. The strength of the association between duration of diabetes and incidence of diabetic retinopathy increased rapidly during a period of 5 to 10 years duration of diabetes.

TRIAL REGISTRATION

C000000222 ( www.umin.ac.jp )

FUNDING

This study is supported by the Ministry of Health, Labour and Welfare, Japan.

Epidemiology of diabetic retinopathy and macular oedema: a systematic review

AIMS

To systematically review the literature on the prevalence and incidence of diabetic retinopathy (DR) and macular oedema (MO).

METHODS

A search of the bibliographic databases (Medline, Embase, CINAHL) was conducted up to October 2001. Selected relevant studies were scrutinized and included in the review.

RESULTS

A total of 359 studies were included. The studies were reported in nearly 100 different journals and in over 50 countries. The majority of the studies were US-based, with large studies such as the Wisconsin Epidemiologic Study of Diabetic Retinopathy dominating the literature. The studies were quite dated and highly heterogeneous in nature in terms of patient selection with variable inclusion criteria (age range, gender, diabetes duration and type, ethnicity, comorbidity, and DR status, assessment, and classification).

CONCLUSIONS

There are inconsistencies between epidemiological studies, and differences in study methods may contribute to conflicting reports of prevalence and incidence of DR and MO in diabetic populations. As new therapies for DR and its associated complications emerge, the need to capture and monitor new epidemiological data becomes increasingly important to be able to assess the impact and effectiveness of these therapies. Robust, longitudinal capture of patient data is, therefore, essential to evaluate the impact of current practice on the epidemiology of diabetic eye complications.

Incidence of diabetic retinopathy in the Barbados Eye Studies

PURPOSE

To examine the 4-year incidence and risk factors for diabetic retinopathy (DR) among black participants with diabetes in the Barbados Eye Studies (BES).

DESIGN

Population-based incidence study.

SETTING AND PARTICIPANTS

Four hundred ten persons with diabetes mellitus (DM) from the BES cohort, which was based on a simple random sample of Barbadians, 40 to 84 years of age at baseline.

MAIN OUTCOME MEASURES

Development of DR, assessed by independent gradings of 30 degrees color stereo fundus photographs of the disc and macula. Associations were evaluated by logistic regression analyses.

RESULTS

After 4 years, DR developed in 92 of 306 (30.1%; 95% confidence interval, 25.0%, 35.5%) persons unaffected at baseline. The incidence of DR was 31.9% in those with known DM at baseline and 20.9% in newly diagnosed DM. Clinically significant macular edema developed in 16 (4.5%) of 353 individuals at risk. Seven (6.9%) of the 101 persons with minimum or moderate DR at baseline progressed to proliferative DR. Age-specific incidence declined from 36.2% at age 40 to 49 years to 28.8% and 24.2% over the subsequent two decades, increasing to 38.2% among those >/=70 years. Risk factors for DR were increased systolic blood pressure (relative risk [RR], 1.16 [1.03, 1.31]/10 mmHg increase); use of oral hypoglycemics (RR, 2.4 [1.3, 4.2]); and use of insulin (RR, 6.1 [1.7, 22.1]) (vs. no treatment or diet only); and elevated glycated hemoglobin (GHb; RR, 6.4 [2.5, 16.0]); GHb >11.5% vs. GHb </=8%).

CONCLUSIONS

High rates of incident DR were evident in the black BES population, also known to have high rates of DM. Prevention of visual loss caused by DR in this population has high priority, including optimal glycemic and blood pressure control.

Risk factors for the development of diabetic retinopathy in Japanese type 2 diabetic patients

This study investigated the risk factors for development of diabetic retinopathy (DR) in 787 type 2 diabetic patients with no retinopathy at the first visit. The subjects were followed up for at least 3 years (mean, 6.7 years). Among the baseline factors, significant correlations were observed between the development of DR and HbA1c (P < 0.0001), the method of therapy (P < 0.005), the duration of diabetes at the first visit (P < 0.005) and the past maximal body mass index (BMI) (P < 0.01). No significant correlation was found with the blood pressure, age, gender, TC or BMI. Among the follow-up variables, the mean HbA1c (P < 0.0001) and duration of diabetes (P < 0.001) correlated significantly with DR development, whereas the blood pressure and age did not. We found that a 1% decrease in HbA1c led to a 35% reduction in the risk of development of DR during the follow-up. The patients whose HbA1c at the first visit was higher than the median value of 8.2% showed a higher probability of development of DR during the next 3 years even when the same blood glucose control was maintained during the follow-up. In conclusion, our study demonstrated that the most important risk factor influencing the development of DR was the blood glucose control. Moreover, we found that the glycemic level at the first visit also influenced the development of DR.

Diabetic retinopathy and control of diabetes with special reference to blood glucose levels

Data concerning diabetic retinopathy were collected prospectively in the Diabetes Clinic of the Third Department of Internal Medicine, University of Tokyo, from the beginning of the Clinic in 1957 until 1985. These data are analyzed here. The prevalence and severity of the retinopathy at the initial visit was strongly related to the duration of diabetes before examination. Pretreatment fasting blood glucose levels were also significantly related. During follow-up, the incidence of retinopathy was most strongly influenced by the degree of control of blood glucose, followed by other factors like blood pressure, age at diagnosis, etc. The effectiveness of sulfonylurea on retinopathy was not inferior to insulin so long as good control was obtained. It was deduced from the analysis of the chain of events that dot hemorrhage is the initial component of diabetic retinopathy, followed by hard exudate, blot hemorrhage, soft exudate and proliferative retinopathy. A six-year fluorescein angiography follow-up of well-controlled non-insulin dependent cases with mild retinopathy showed that microaneurysms disappear rapidly during the first year and more slowly thereafter. The avascular areas once formed seem to progress despite the degree of control exerted here. The other Japanese results are discussed.

A four-year follow-up study on the incidence of diabetic retinopathy in older onset diabetes mellitus

Out of 369 diabetic patients with an age at onset of diabetes > or = 30 years previously studied, 325 (88%) were included in an ophthalmological follow-up examination 4 years later. In patients treated with oral drugs at baseline, the incidence of any type of retinopathy was 30.8% and of severe retinopathy 5.7%. All patients who developed severe retinopathy received insulin during the follow-up period. At baseline, duration of diabetes, diastolic blood pressure, and signs of nephropathy (p < 0.05 in all cases) as well as degree of metabolic control (p < 0.01) differed between patients who developed retinopathy and those who did not. At follow-up, there were no longer any differences regarding degree of metabolic control and diastolic blood pressure. In patients treated with insulin at baseline, the incidence of any type of retinopathy was 41.0% and of severe retinopathy 16.1%. At baseline, duration of diabetes (p < 0.01), degree of metabolic control, and insulin dosage (p < 0.05 in both cases) differed between patients who developed retinopathy and those who did not. At follow-up, there was no longer any difference in insulin dosage.