AIM: To use spectral domain optical coherence tomography(SD-OCT)to measure macular subfoveal choroid thickness(SFCT)in patients with diabetic retinopathy(DR), observe the changes of SFCT, and to explore the relationship between SFCT and diabetes mellitus and diabetes retinopathy.

METHODS: A total of 152 patients with type 2 diabetes(T2DM)were collected and grouped according to their fundus conditions. There were 72 cases in the NDR group and 80 cases in the DR group. Eighty-five healthy subjects were used as the control group. Follow-up according to the clinical stage of DR, where the DR components were mild NPDR, moderate NPDR, severe NPDR and PDR. According to the United Nations World Health Organization, the age group was divided into three age groups: 18-44 years old(youth group), 45-59 years old(middle-aged group), and 60-75 years old(old group). Analyzed and compared the SFCT between each group.

RESULTS:There was no statistically significant difference in SFCT between the T2DM group and the control group(P>0.05). The SFCT of the all group was not significantly correlated with age and course of disease(P>0.05); the SFCT of the control group was negatively correlated with age(P<0.05), and the SFCT of the elderly group was thinner than that of the middle-aged group and the young group(P<0.05). There was no significant difference between young and middle-aged(P>0.05). The SFCT of the T2DM group was thinner than the control group(P<0.001), and the SFCT of the NDR group and the DR group were thinner than the control group(P<0.001); the difference in SFCT between DR staging was statistically significant(P<0.001).

CONCLUSION: Age is a related factor that affects SFCT. Diabetic SFCT becomes thinner than normal people, and SFCT thickens with the severity of DR lesions.