Diabetic Retinopathy in the Thessaloniki Eye Study (TES): Prevalence and Risk Factors

Abstract

Purpose : To report diabetic retinopathy (DR) prevalence and risk factors in TES.

Methods : TES is a cross-sectional population-based study of eye diseases in Greece. 2554 randomly selected Caucasians aged ≥60 years were interviewed for demographics/lifestyle/medical history and underwent detailed ocular examination. Masked fundus photo DR grading was performed using a modified Airlie House classification. The highest score between two eyes defined the subject DR level: no DR, mild, moderate, severe non-proliferative DR (NPDR) and proliferative DR (PDR). Early Treatment Diabetic Retinopathy Study and Eye Diseases Prevalence Research Group definitions were used for clinically-significant macular edema (CSME) and sight-threatening retinopathy (STR), respectively. Self-reported diabetes mellitus (DM) defined diabetic subjects. Diabetics with DR were compared to those without DR for demographic/lifestyle/ocular/systemic factors. Multivariable logistic regression analysis was performed including factors with p<0.2 in univariate model. Odds ratios (OR) and 95% confidence intervals (CI) are reported.

Results : Fundus photos were gradable for 2175 subjects. The prevalence of DR was 6.9%(151/2175). 349 subjects had self-reported DM. The proportion of DR among diabetics was 31.2%(109/349); the proportion of mild, moderate, severe NPDR and PDR was 13.8%(48/349), 7.2%(25/349), 7.4%(26/349) and 2.9%(10/349), respectively. CSME was present in 6.6%(23/349) and STR in 12.0%(42/349) of diabetics. In multivariable analysis, male gender (OR:2.15;95%CI:1.07-4.31), DM treatment (Tx) duration (OR:1.06;95%CI:1.01-1.10 per year), insulin Tx (OR:5.30;95%CI:2.53-11.13), afternoon sleep (OR:2.03;95%CI:1.01-4.07), age (OR:0.88;95%CI:0.83-0.93 per year), migraine (OR:0.11;95%CI:0.01-0.97) and regular alcohol intake (Vs no/occasional,OR:0.41;95%CI:0.21-0.78) were significantly associated with DR. 27.8% of DR subjects did not report DM. 76.6% of DR subjects were unaware of DR presence.

Conclusions : Almost one third of diabetics had DR. Male gender, insulin Tx and longer DM Tx were related to higher DR risk. The positive association of afternoon sleep and the inverse association of age with DR may imply poor health status and selective mortality. The protective role of moderate alcohol intake may reflect beneficial vascular effects. High undiagnosed DR and undiagnosed DM rates in DR subjects highlight the need of improved primary and eye healthcare.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.