To Örebro University

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.

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.