Risk factors for incidence and progression of retinopathy in type 2 diabetes in Dongguan city

Abstract

Background Diabetic retinopathy (DR) is one oi primary causes of blindness in young adutts with the increase of incidence of diabetes mellitus (DM).To strengthen the anlysis of risk factors for incidence and progression of retinopathy is very important for the prevention and control of DR in China.Objective The aim of this study was to describe the risk factors associated with DR in type 2 DM patients aged 40 ycars and older in Hengli town,Dongguan city in Southern China.Methods A population-based cross-sectional study was performed.A total of 8952 Han Chinese from 16 villages and a community participated in the census of DM based on the diagnosis criteria of American Diabetic Association (2010 Version),and then the DR was screened and staged from the DM patients according to International Clinical Classification System of DR and DME (Sydney,2002).Participants underwent standardized interview,physical,laboratory and ocular examination.Ocular examination included visual acuity(best corrected visual acuity and presenting visual acuity),intraocular pressure,anterior and posterior segment examinations,fundus and optic disc photography.x2 test,independent sample t test and one way analysis of virance was respectively used to compare the differences of examing indexes between DR and non-DR (NDR).Univariate and stepwise logistic regression analysis were used to identify independent risk factors.Results Stepwise logistic regression analysis revealed that male,longer DM course,systolic pressure,hyperglycemia and glycosylated hemoglobin were the independent risk factors of DR.Compared with females,males had a higher risk of DR (OR =1.914) (95％CI:1.382-2.651).The risk of DR was significantly increased in the DM patients with the duration of 1-4 years,5-9 years and ≥ 10 years in comparison with newly diagnosed DM patients (OR =3.336,95％ CI:2.322-4.880 ; OR =3.890,95％ CI:2.327-6.503 ; OR =12.499,95％ CI:6.607-23.647).DM patients with blood pressure 120-139 mmHg and ≥ 140 mmHg showed a higher risk of having any DR than those with blood pressure ≤ 120 mmHg (OR =1.953,95％ CI:1.081-3.528 ; OR =1.950,95％ CI:1.076-3.532).Compared with DM patients with fasting blood glucose ≤5.6 mmol/L,DM patients with 5.6-6.9 mmol/L and≥7.0 mmol/L had a higher risk of having any DR (OR=1.567,95％ CI:0.889-2.732) and OR =2.170,95％ CI:1.252-3.761).Compared with DM patients with glycosylated hemoglobin＜6.5％,DM patients with ≥ 6.5％ had a higher risk of having any DR (OR =1.577,95％ CI:1.105-2.253).Conclusions This study indicates that male,duration of diabetes,systolic pressure,hyperglycemia and glycosylated hemoglobin are independent risk factors of DR in type 2 DM patients.These findings suggest that controlling hyperglycemia,hypertension and body weight index may lower the risk of having DR associated with type 2 DM. Key words: Diabetes mellitus/complication; Diabetic retinopathy; Risk factor; Epidemiology