Lower haemoglobin level and subsequent decline in kidney function in type 2 diabetic adults without clinical albuminuria

Abstract

Aims/hypothesis: Anaemia has been suggested to be an independent risk factor for subsequent progression of advanced diabetic nephropathy; however, the relationship between haemoglobin levels and progression of nephropathy in patients without clinical albuminuria is unknown. Methods: We conducted this prospective hospital-based cohort study of 464 type 2 diabetic patients (149 women and 315 men, 55±13 [mean±SD] years of age) with serum creatinine <177 μmol/l (2.00 mg/dl) and urinary albumin : creatinine ratio <300 mg/g creatinine. GFR was estimated using the equation formulated by the Modification of Diet in Renal Disease Study group, refitted for Japanese individuals. Most patients had haemoglobin concentrations in the normal range (144±15 g/l), only modest renal impairment (GFR: 74.8±14.5 ml min −1 1.73 m −2 ), and normal urinary albumin levels (81.5/18.5% with normo-/microalbuminuria). The primary outcome measurement was the rate of change in GFR determined by regression analysis with GFR as a function of time. Patients were followed up for a mean observation period of 5.0±0.9 (range: 2.5 to 6.2) years. Results: Univariate and multiple regression analyses yielded a significant association between the rate of change in GFR and baseline haemoglobin concentration. After adjusting for covariates, the rate of decline in GFR was significantly greater in patients in the lowest haemoglobin quartile (−3.27 ml min −1 1.73 m −2 year −1 ) than in the third (−2.71 ml min −1 1.73 m −2 year −1 , p=0.024) and highest quartiles (−2.78 ml min −1 1.73 m −2 year −1 , p=0.046). Conclusions/interpretation: Lower haemoglobin concentrations in type 2 diabetic patients without clinical albuminuria may be a significant predictor of subsequent decline in GFR.

Normoalbuminuric Renal-Insufficient Diabetic Patients

“…It must be noticed that most of the clinical events occurred in CKD patients with macroalbuminuria. The different characteristics we found may have contributed to this better outcome: male sex (32), a longer duration of diabetes (33), the presence of retinopathy (34), a lower hemoglobin level (32,35), and smoking (36) have all been reported to be associated with the progression of nephropathy in diabetes. However, the most probable is the persisting absence of albuminuria by itself: numerous reports have emphasized its importance for CKD progression (30,(33)(34)(35)37,38) and coronary heart disease (39) in diabetes.…”

Lack of association between anemia and renal disease progression in Chinese patients with type 2 diabetes

“…Anemia has shown to be a predictor for ESRD or renal disease progression in most9, 10, 23, but not all, studies24. In the Multiple Risk Factor Intervention Trial involving middle‐aged men without significant kidney disease, there was no association between baseline hematocrit and development of ESRD after a follow up of 25 years24.…”

“…also reported that baseline hemoglobin did not correlate to the subsequent decline rate of eGFR26. In diabetes patients, although many studies showed that anemia was an independent risk factor for ESRD or renal disease progression, few of them9, 10, 23 analyzed the interaction between anemia and eGFR.…”

“…Increasing evidence shows that low hemoglobin level contributes to the progression of left‐ventricular hypertrophy, heart failure, all‐cause and cardiovascular mortality6, 7. Similar effects of anemia on the development of nephropathy were also shown8, 9. Anemia at baseline was shown as an independent risk factor for ESRD in several groups of high‐risk patients including diabetes10.…”

The Incidence of Anemia in the Adult Working Population of Vojvodina

“…The study of Lippi et al found a high prevalence of anemia and anisocytosis in a population of emergency department patients, whose identification may be important for appropriate treatment and favorable outcome (13). In diabetic patients, through renal hypoxia that stimulates production of different growth factors (transforming growth factor-b1, vascular endothelial growth factor, platelet-derived growth factor) and cytokines, anemia contributes to the development of interstitial fibrosis, i.e., scarring and thickening of the kidney (14,15). Correction of anemia in these patients significantly reduces the proportion of patients that will have a double increase in serum creatinine levels (16).…”