The prevalence and severity of retinopathy in patients with coronary artery disease at a tertiary hospital in Durban, South Africa.

Abstract

Background Studies have described the prognostic value of retinopathy in coronary artery disease (CAD) but few have examined the relationship between retinopathy and the CAD severity. Aim The study investigated the prevalence of retinopathy in CAD patients [acute coronary syndrome (ACS) and chronic stable CAD] and determined the association of retinopathy and other clinical factors with the extent of coronary artery disease as assessed by the number of epicardial vessels involved. Methods A cross sectional prospective study of 121 in-patients was undertaken over a ten-month period at Inkosi Albert Luthuli Central Hospital. One hundred and nine patients (12 stable CAD, 97 acute coronary syndrome) had angiographically confirmed CAD and the remaining 12 patients with normal angiograms served as controls. All participants had a comprehensive systemic evaluation and fasting biochemistry. Retinopathy was assessed using five to seven wide field fundus photographs. Macular thickness, vessel density and macular perfusion were assessed with optical coherence tomography (OCT) and OCT angiography. Results Compared to subjects with normal angiograms (controls), those with CAD had more frequent diabetes (67.9% vs 16.7%, p<0.001). Triple vessel disease (TVD) was present in 43.4% of diabetic patients compared to 35.6% of non-diabetics (p=0.004). Multivessel involvement was more frequent in diabetics (79%) compared to nondiabetics (58%), (p=0.002). xi The prevalence of any form of retinopathy was 66% in the CAD group and 33% in the control group (p=0.026). Subjects with double vessel disease (DVD) were more likely to have any form of retinopathy (77.8%) compared to those with single vessel disease (65.2%) and triple vessel disease (59.2%) (p=0.027). Diabetic retinopathy (DR) was present in 34 subjects (31.2%) in the CAD group and one subject (8.3%) in the control group (p=0.097). The majority of CAD patients with DR had non-proliferative diabetic retinopathy (NPDR) (n=29, 85.3%) and five (14.7%) had proliferative diabetic retinopathy (PDR). Patients with CAD and DR were more likely to have microalbuminuria compared to those without CAD and DR (p=0.014). An irregular foveal avascular zone (FAZ) was more frequent in the subgroup of CAD with diabetes (n=15) compared to the CAD without diabetes (n=1) group (21.3% vs 2.9%, p=0.013). In bivariate analysis, diabetes was strongly associated with having CAD and any form of retinopathy (OR = 0.238, CI = 0.109-0.517, p<0.001). Hypertensive retinopathy was present in 43 (40.2%) subjects in the CAD group and three (25%) in the control group (p=0.306). More than 60% of the CAD patients with HR had grade 2 retinopathy; only one CAD subject had grade 3 HR. Subjects with CAD and hypertensive retinopathy were more likely to be between the ages of 55-64 years (41.9%, p=0.016), to be smokers (p=0.034) and have the metabolic syndrome (p=0.004). Conclusion Retinopathy was a frequent finding in this sample group of predominantly ACS subjects and was associated with clustering of the major risk factors. The presence of DR, microalbuminuria and foveal abnormalities in diabetic subjects with CAD suggest underlying coronary microvascular disease. This study calls for surveillance of subjects with retinopathy to detect the presence of CAD.