AIM: To investigate the correlation between axial length and diabetic retinopathy(DR)in patients with type 2 diabetes mellitus.

METHODS:This study is a cross-sectional study. A total of 53 cases(104 eyes)of type 2 diabetes patients who admitted to the ophthalmology department of the Jining No.1 People's Hospital between January and May 2023 were included. Among these cases, 51 patients had both eyes included, while 2 patients had only one eye included. The patients were divided into two groups based on the presence or absence of fundus lesions. The non-diabetic retinopathy(NDR)group consisted of 32 eyes, and the DR group consisted of 72 eyes. Within the DR group, the patients were further categorized based on the severity of fundus lesions. The non-proliferative diabetic retinopathy(NPDR)group comprised of 27 eyes, and the proliferative diabetic retinopathy(PDR)group consisted of 45 eyes. The axial lengths of eyes in the DR group were divided into four groups using quartiles: 19 eyes in the 20.00～22.09 mm group, 17 eyes in the 22.10～22.70 mm group, 18 eyes in the 22.71～23.12 mm group, and 18 eyes in the 23.13～24.48 mm group. Binary Logistic regression analysis was employed to investigate the factors influencing the occurrence of DR and PDR.

RESULTS:Binary Logistic regression analysis showed that both axial length and age significantly influenced the development of DR and PDR.(Axial length: OR=0.296, 95%CI:0.130～0.672, P<0.05; OR=0.237, 95%CI:0.076～0.736, P<0.05; age: OR=0.949, 95%CI:0.907～0.994, P<0.05; OR=0.879, 95%CI: 0.820～0.942, P<0.05). The risk of PDR in the group with axial length of 23.13～24.48 mm was reduced compared to the group with axial length of 20.00～22.09 mm(OR=0.057; 95%CI: 0.006～0.515, P=0.011).

CONCLUSION:The findings indicate that longer axial length in patients with type 2 diabetes are associated with a decreased risk of developing DR, as well as a reduced likelihood of DR progressing to PDR. Therefore, a long axial length can be considered a protective factor against DR.