Prevalence of anemia in patients with type 1 and type 2 diabetes mellitus with chronic renal disease

Abstract

Background . Diabetes mellitus (DM) is a non-infectious disease with a high prevalence worldwide and is one of the most common causes of diabetic kidney disease (DKD). Anaemia is a well-known complication of chronic kidney disease (CKD) and has been estimated to affect one in three adults with DM. Aims . To evaluate the prevalence and severity of anaemia among patients with DKD and to compare the distribution of anaemia among patients with diabetic and non-diabetic CKD. Methods . A total of 2,015 patients with DM [n = 807 with type 1 DM (T1DM); n = 1,208 with type 2 DM (T2DM)] and 244 patients with biopsy-proven chronic glomerulonephritis (CGN) were selected. Patients with glomerular filtration rate (GFR) of <15 ml/min/1,73 m2 (stage 5 CKD) and treated by erythropoietin-stimulating agents and/or iron medication were not included. The presence of anaemia was defined as haemoglobin (Hb) of <130 g/l in men and <120 g/l in woman. GFR was calculated using the MDRD formula. CKD stages were defined based on stages 1–4 of CKD by KDOQI and KDIGO guidelines: stage 1 (GFR ≥ 90 ml/min/1.73 m2); stage 2 (GFR 60–89 ml/min/1.73 m2); stage 3 (GFR 30–59 ml/min/1.73 m2); stage 3a (45–59 ml/min/1.73 m2); stage 3b (GFR 30–44 ml/min/1.73 m2); stage 4 (GFR 15–29 ml/min/1.73 m2). Results . Rates of anaemia were higher among patients with DM and DKD (38.8% and 22.6% for T1DM and T2DM, respectively) than diabetic patients without DKD (16.6% and 11.5%, respectively. Prevalence of anaemia by CKD stage increased from 23.3% in stage 1 to 80% in stage 4 among patients with T1DM, and from 16.9% to 81 % among patients with T2DM. The prevalence of anaemia was also higher among protoeinuric patients (53.9% and 34.4% for T1DM and T2DM, respectively) relative to microalbuminuric patients (29.4% and 17.6%, respectively). Anaemia prevalence was significantly greater in DKD due to T1DM (53.9%) than in CGN (19.7), and the rates did not differ based on stages of CKD. Conclusions . We found a two-fold higher rate of anaemia among patients with DM and CKD than patients with DM and non-DKD. In addition, we found that the frequency of anaemia depends on renal function (i.e., stage of CKD) and degree of albuminuria. Taken together, anaemia is highly prevalent among patients with T1DM and DKD compared with patients with chronic CGN, without differences in its severity.