[Relationship between the classification of diabetic macular edema and its related factors]

To explore the relationship between the classification and degree of diabetic macular edema (DME) and the stages of diabetic retinopathy (DR), diabetic duration, classification of diabetes, use of insulin, and visual loss.

We retrospectively analyzed the stages of DR, diabetic duration, classification of diabetes, use of insulin, and visual loss in 1 172 DR patients with fundus fluorescein angiography (FFA). The occurrence of DME in DR in each stage and the relationships between its related factors were analyzed.

In 1 172 patients, 633 eyes in 394 patients had DME (33.62%), including 265 (41.86%) with focal DME and 368 (58.14%) with diffuse DME. There were 246 (38.86%) eyes with mild DME, 189 (29.86%) with moderate DME, and 198 (31.28%) with severe DME. Significant correlations exhisted among the classification of DME (r = 0.975, P = 0.025), the degree of DME (r = 1.000, P = 0.000), and the stage of DR. DME deteriorated with the increase of the stages of DR. The visual loss significantly correlated with the degree of DME (r = -0.984, P = 0.003). The visual acuity was lower in patients with diffuse DME than those with focal DME. The diabetic duration significantly correlated with the classification and degree of DME (r = 0.962, P = 0.009). DME was mostly seen in patients with a disease course of six years or longer, and its severity and incidence increased along with the prolonged period. Also, The incidence of DME increased in patients with type 2 diabetes and patients who used insulin.

The classification and degree of DME correlates with the stages of DR, diabetic duration, the classification of diabetes, the use of insulin, and visual loss.