Abstract
Purpose: :
To explore the protective factors that prevents patients from developing of proliferative diabetic retinopathy after a long-term history of the type 2 diabetes mellitus.
Methods: :
A retrospective, hospital-based cross-sectional analysis was conducted from a database composed of 1715 type 2 diabetes patients with medical care for at least 1 year in the endocrinology department of our hospital from 2001 to January 2009. A group of 65 patients without retinopathy after 20 years of diabetes mellitus (group 1) was identified to compare with 79 patients who developed proliferative diabetic retinopathy within 20 years (group2). All of the patients received a dilated fundus examination to recognize diabetic retinopathy (DR) by experienced ophthalmologists. Factors analyzed included age, age of disease recognized, hemoglobin level, white blood cell counts, platelet count, hsCRP, HbA1C level, systemic hypertension, blood lipid profiles, body mass index, kidney function, peripheral circulation and neuropathy. Statistical analysis of multivariate analysis was conducted by binary logistic regression to identify the independent protective or risk factor of proliferative diabetic retinopathy.
Results: :
The mean age of patients in group 1 and group 2 was 69.5 and 60.3 years old, respectively (p<0.001). The patients without retinopathy after long diabetes life had a lower hsCRP (1.18 vs. 2.59 mg/L, p=0.04), lower WBC count (6.55 vs. 7.44 x103/dL, p=0.014), a higher Hb level (12.9 vs. 11.6 g/dL, p<0.001), lower HbA1C (7.3 vs. 7.8 %, p=0.015), lower BMI (25.1 vs. 28.0, p<0.01), lower blood triglyceride (103.1 vs. 130.8 mg/dL, p=0.015), better kidney function (GFR 65.4 vs. 48.2 mL/min, p<0.001), less neuropathy (29.8 vs. 56.9%, p=0.02) and a lower rate impaired peripheral circulation (31.2% vs. 59.6%, p=0.02). Logistic regression analysis showed that hemoglobin level was associated with a decreased risk (odds ratio = 0.62 per g/dL, 95% C.I.= 0.475 to 0.816, p=0.001) of proliferative diabetic retinopathy.
Conclusions: :
A higher hemoglobin level is a protective factor of advanced retinopathy with long diabetic history. Treatment of anemia could be a potential strategy for preventing diabetic retinopathy.
Keywords: diabetic retinopathy • clinical (human) or epidemiologic studies: risk factor assessment