Prevalence of diabetic retinopathy and its relationship with glomerular filtration rate and other risk factors in patients with type 2 diabetes mellitus in Spain. DM2 HOPE study.

Aim: Diabetic retinopathy (DR) is the leading cause of blindness in working age population in developed countries. Albuminuria and estimated glomerular filtration rate (eGFR) have been considered biomarkers for DR. This study aimed to investigate the prevalence of DR and its relationship with eGFR and other risk factors in type 2 diabetic patients (T2DM) in Spain.

Methods: A cross-sectional and descriptive study has been performed in 14,266 patients. Clinical records were reviewed. Demographic data, clinical diagnoses, clinical variables, and results from laboratory tests were recorded. Prevalence rates of DR were calculated. Logistic regression analysis was applied to assess predictors of the DR presence/absence.

Results: DR prevalence was 14.9%, being more prevalent in women (p = 0.0087) and in older patients (p < 0.0001). Duration of disease (OR = 5.3, IC95% = 3.8-7.4; p < 0.0001), eGFR < 60 ml/min/1.73 m (OR = 2.0, IC95% 1.6-2.4; p < 0.0001), levels of HbA1c ≥ 7% (OR = 1.9, IC95% = 1.5-2.3; p < 0.0001) and high blood pressure (OR = 1.6, IC95% = 1.2-2.1; p = 0.0032) were associated with higher risk of DR. DR was also more frequent in patients taking insulin (32,6% vs. 10,2%; p < 0.0001).

Conclusion: Around one in seven patients with T2DM has DR after nine years since diagnosis. Time since diagnosis, insulin therapy, cardiovascular profile, and renal dysfunction are associated with DR in patients with T2DM in Spain.