To Örebro University

BACKGROUND: A better characterization of diabetic retinopathy (DR) may be helpful to monitor early disease, predict progression of DR, and to evaluate new treatment strategies. Visual function has been suggested to complement the assessment of microvascular lesions in DR but needs to be evaluated in longitudinal studies. OBJECTIVES: This prospective longitudinal cohort study investigated whether early visual field deterioration in diabetes is associated with change in DR, and whether known risk factors as diabetes duration and glycated A1c (HbA1c) affect the visual field.

METHODS: People living with diabetes, 18 to 75 years of age, were consecutively recruited from the local DR screening program. Individuals with eye diseases other than DR that could affect the visual field, and those who had received previous local eye treatment for DR, could not be included. Participants who had completed a five-year follow-up were re-examined after nine and ten years from baseline. The most important outcome was deterioration in series of visual fields as determined by an experimental model tailored for people living with diabetes. Stages of DR were evaluated according to the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, and glycemic control by measurement of HbA1c.

RESULTS: Fifty-six participants (median age 69 years at the last visit, 35 males) completed 608 out of 616 scheduled visits during ten years of follow-up. Progression and regression of DR occurred most often between no (ETDRS level 10) and minimal (ETDRS level 20) DR. The number of deteriorated test points increased annually by 11% (95% CI: 6.9-15.3) and were not associated with change in DR but with higher levels of HbA1c.

CONCLUSIONS: Early deterioration of visual function occurred independently of DR and was associated with worse glycemic control, suggesting that the metabolic disturbances due to diabetes induced a primary deterioration of sensitivity in the visual field.

Purpose: To investigate the prevalence, incidence and risk factors of DR in elderly people living with type 2 diabetes.

Methods: Individuals >80 years, in the Swedish National Diabetes Register (NDR) between 2008 and 2017, were included. Prevalence and incidence were calculated and stratified by age. Estimates were assessed by longitudinal binary logistic regression models.

Results: One hundred forty-one thousand, one hundred fifty-eight individuals with type 2 diabetes were included, median age 83 years, 53.3% females and with a median HbA1c 52 mmol/mol. The DR prevalence was stable at 336.2 cases/1000 patients in 2008 (95% CI, 330.2-342.3), with no significant changes during the 10-year period. Crude DR incidence rate: 88.5 cases/1000 patient years (95% CI, 87.6-89.4). The incidence rate was lower at higher ages. The effect of age on incident DR varied by sex, with females having an increasingly higher risk than males from 83 years of age, OR 1.25 (1.11-1.42) at age 90 years. The risk of incident DR with longer diabetes duration increased more rapidly at worse glycaemic control.

Conclusion: The growing population of elderly with type 2 diabetes shows a stable proportion of DR and proposes an increased need for DR screening and eye care. Established risk factors for DR, such as diabetes duration and level of glycaemic control, are also important in the elderly; however, age and sex should be considered.

DESIGN: Cross-sectional retrospective cohort study.

PURPOSE: To investigate if quantifying retinal microvascular lesions is a reliable outcome measure in elderly.

METHODS: Fundus photographs from all patients with type 2 diabetes, age ≥80 years, visiting the screening program 2008 in Region Värmland Sweden, n = 668, were reviewed. Inclusion criteria were mild/moderate diabetic retinopathy (DR) according to the International Diabetic Retinopathy Severity Scale. Exclusion criteria were hard exudates within two disc-diameters, and microaneurysms or haemorrhages within one-disc diameter, from the centre of the macula. Two observers counted microaneurysms and haemorrhages independently. Outcome measures were the total sum of microaneurysms and the total sum of haemorrhages per patient. Correlation, agreement and reliability between the counts of the observers was assessed. Analyses microaneurysm counts utilized all included patients while analyses of haemorrhages those with at least moderate DR in one eye.

RESULTS: In total 101 patients met the inclusion/exclusion criteria, median age 82 years and 50.5% were of female sex. Moderate DR in at least one eye was present in 59 patients. In all patients the number of microaneurysms ranged from 1-82, and among patients with at least moderate DR the haemorrhages ranged from 1–29. For microaneurysm count the Pearson correlation coefficient was 0.896 p < 0.001 and intraclass correlation coefficient (ICC) was 0.944 (95% CI 0.917–0.962) between the two observers. For haemorrhage count the Pearson correlation coefficient was 0.897 p < 0.001 and ICC was 0.94 (95% CI: 0.893–0.965) between the two observers.

CONCLUSIONS: Retinal microaneurysm count and haemorrhage count was assessed with excellent reliability. The results suggests that retinal microvascular lesions in elderly with diabetes can be manually quantified but the usefulness of such measures needs further evaluation.

INTRODUCTION: Screening for diabetic retinopathy (DR) prevents blindness through the early detection of sight-threatening retinal microvascular lesions that respond to timely local treatment. However, the provision of easy and regular access to DR screening programs is currently being challenged by the increasing prevalence of diabetes. One proposed solution is to extend the screening interval for patients at low risk for progression of retinopathy. To date, most providers of screening programs have hesitated to implement a strategy of extended intervals due to the lack of data on whether adherence and safety are compromised when retinal examinations occur less frequently. In the study reported here, we investigated adherence to the screening program and progression of retinopathy in patients with type 2 diabetes participating in a DR screening program with extended intervals.

METHODS: This was a retrospective study that included 1000 patients with type 2 diabetes mellitus who attended a screening program for DR. The patients were consecutively placed into a low-risk patient cohort with no retinopathy or into an intermediate-risk patient cohort with mild retinopathy (each cohort n = 500). Screening intervals were 36 months for the low-risk cohort and 18 months for the intermediate-risk cohort.

RESULTS: The 1000 subjects enrolled in the study had a median age of 68 (interquartile range 12) years and 60.4% were men. At the follow-up screening visit, data on 102 subjects were not included in the analysis of adherence rate due to death, severe systemic illness, other concurrent eye disease or migration. Among the 898 remaining subjects, adherence to the screening program was 93.7% (413/443) in the 36-month group and 98.3% (449/455) in the 18-month group (p < 0.0001). Non-adherence decreased with increasing age (odds ratio 0.92, 95% confidence interval 0.888-0.954, p = 0.0005). At follow-up, 65 subjects showed progression of retinopathy; none had worse than moderate retinopathy. Risk factors for DR and treatment for hyperglycemia, hypertension and hyperlipidemia were compared among subjects in the low-risk cohort: non-adherent subjects did not differ from their adherent counterparts without progression of DR, but the former had a shorter duration of diabetes and higher diastolic blood pressure than adherent subjects with progression of DR (4.5 vs. 7.5 years, p = 0.007; and 80 vs. 75 mmHg, p = 0.02, respectively).

CONCLUSION: The results suggest that screening DR at extended intervals can be achieved with high adherence rates without compromising patient safety. However, younger subjects and those at higher risk of progression may require extra attention.

We explored signs of retinal dysfunction over time in diabetic subjects before or early in the course of retinopathy. Patients with no, mild, or moderate retinopathy were consecutively recruited and underwent standard automated perimetry, visual acuity measurement, and fundus photography. These examinations and measurements of HbA(1c) and blood pressure were repeated for up to 5 years from baseline. Visual field improvement/deterioration in diabetic subjects was evaluated using significance limits for change. Progression or regression of retinopathy was defined as a two-step change on the Early Treatment Diabetic Retinopathy Study final severity scale. Seventy-four subjects completed at least 3 years of follow-up, and 22% showed visual field worsening, defined as repeated significant deterioration at 10% of the test points, whereas only 1% showed field improvement. Worsening occurred in subjects both with and without vascular lesions. The degree of retinopathy was stable throughout the observation period in 68 of 74 eyes, improved in 4, and worsened in 2. Visual field deterioration was not correlated with a change in retinopathy. By using perimetry with an analysis tailored for monitoring diabetic subjects, we were able to demonstrate progression of retinal dysfunction over time, which may represent early signs of retinal neurodegeneration.

Purpose: To presents results after 18months of follow-up of a longitudinal study aiming at exploring the correlation between diabetic retinal vascular lesions and functional change.

Methods: Patients were consecutively recruited from attendees to the screening program for diabetic retinopathy. Subjects are followed every sixth month for the first 3years and thereafter annually up to 5years. Progression of diabetic retinopathy is evaluated using the Early Treatment Diabetic Retinopathy Study (ETDRS) scale and improvement/deterioration in visual fields by predefined significance limits for change.

Results: Of 81 subjects, with no/mild/moderate diabetic retinopathy included, 76 have passed the 18-month visit. At that time, retinal progression by two steps according to the ETDRS scale had occurred in two subjects. Visual acuity was -0.14 logMAR and had decreased with two letters (0.04 logMAR) (p<0.001) from baseline. The global visual field index mean deviation was almost unchanged with a negligible improvement of 0.03dB (p=0.79). In 21 subjects, repeated significant deterioration was seen in 10% of all points tested in the field, while almost no improved points were noted. The two subjects with retinal progression were not among those 21 with indication of perimetric progression.

Conclusions: This is, to our knowledge, the first longitudinal study evaluating change of visual fields in a representative diabetic cohort with no or mild/moderate retinopathy. In this interim report, we demonstrate deteriorated perimetric sensitivity in subjects already at 18months of follow-up. The results will have implications for evaluating change in visual function in future clinical trials.

PURPOSE: To investigate how refraction and visual acuity may vary in patients with diabetes under routine care.

METHODS: Fifty-three eyes of 53 patients with various degrees of diabetic retinopathy were examined prospectively on four different occasions within a month. Refraction, best-corrected visual acuity (expressed as logMAR score) and blood glucose were measured on each occasion. Intraindividual variability was calculated as the range between the highest and lowest measurements. Associations between blood glucose levels and each of the other variables were tested by linear regression analysis for each patient.

RESULTS: Refraction was completely stable in 43 patients and changed only slightly in 10, in whom the mean intraindividual variability of the spherical equivalent was 0.4 dioptres. Visual acuity test results were also highly reproducible. Mean intraindividual variability in visual acuity was 0.08 logMAR. Mean haemoglobin A1c (HbA1c) was 7.3 ± 1.5% but individual blood glucose levels ranged from 2.8 to > 22.2 mmol/l. Intraindividual variability ranged from 0.5 to 18.1 mmol/l, with a median of 6.0 mmol/l for the entire group. There were no associations between refraction or visual acuity and blood glucose levels or inter- or intraindividual glucose variations.

CONCLUSION: Refraction and visual acuity test results were highly reproducible and stable in patients with reasonably well controlled diabetes but variable blood glucose levels under routine care.