Serum high sensitivity C reactive protein levels in patients with diabetic retinopathy: a cross sectional study


  • Harishchandra R. Chaudhari Department of Medicine. Dr D. Y. Patil Medical College, Hospital and Research Centre, Pimpri, Pune, Dr D. Y. Patil Vidyapeeth, Pune (Deemed to be University), Maharashtra, India
  • Gaurav A. Chaudhari Department of Medicine. Dr D. Y. Patil Medical College, Hospital and Research Centre, Pimpri, Pune, Dr D. Y. Patil Vidyapeeth, Pune (Deemed to be University), Maharashtra, India



Diabetes, Fundus, Glycemic control, Kanski's system, Proliferative


Background: Diabetic retinopathy (DR) is one of the major visual morbidities associated with diabetes. This study determined the levels of serum high-sensitivity C-reactive protein (hs-CRP) in patients with DR and to correlate the estimated levels of serum hs-CRP with the severity of DR and other coexisting factors.

Methods: This was a cross-sectional study conducted between March 2009 and August 2010 and included patients with type 2 diabetes mellitus (T2DM) with or without DR. A detailed fundus evaluation was performed using direct and indirect ophthalmoscopy. The retinopathies were observed and documented in accordance with the Kanski's system of classification as background DR (BDR), pre-proliferative DR (PPDR), and proliferative DR (PDR). Laboratory investigations determined the levels of fasting blood glucose (FBG), postprandial blood glucose (PPBG), glycosylated hemoglobin, urine albumin excretion, and serum hs-CRP levels.

Results: In total, 80 patients with T2DM were included (DR group, n=40 [BDR, n=22; PDR, n=11; PPDR, n=7]; control group, n=40). Highest serum hs-CRP levels were found in PDR group (6.68 mg/L), followed by PPDR and BDR group (3.2 mg/L and 1.56 mg/L, respectively). The PDR group showed the longest duration of diabetes (16 years), highest FBG (221.8 mg/dL) and HbA1c (6.68 mg/L). The incidence of albuminuria and maculopathy was higher in PDR group (72.7% and 54.54%, respectively). A significant association of hs-CRP levels with DR in patients with T2DM was observed. A significantly (<0.005) positive correlation of hs-CRP was also observed with age, duration of disease, FBG, PPBG, and HbA1c.

Conclusions: Patients with severe grades of retinopathy had significantly higher hs-CRP levels than patients with the milder grades.


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