Anemia and Diabetes in the Absence of Nephropathy

Abstract

OBJECTIVE -Patients with diabetes commonly have a greater degree of anemia for their level of renal impairment than those presenting with other causes of renal failure. To clarify the contribution and differing roles of diabetes and nephropathy in the development of anemia in diabetic patients, we examined the hematologic and hematinic parameters of diabetic patients without nephropathy.RESEARCH DESIGN AND METHODS -The study group was comprised of 62 patients with type 2 diabetes who had been followed for a median of 7 years. For the study, these patients had additional samples taken during their annual routine blood testing for the measurement of extra parameters, including serum ferritin, serum erythropoietin (Epo) levels, and the percentage of reticulocytes. These measurements were combined with the routine parameters Hb, hematocrit, HbA 1c , and glomerular filtration rate.RESULTS -In all, 8 of the 45 male patients (17.8%) and 2 of the 17 female patients (11.8%) were classified as anemic (Hb Ͻ13g/dl and Ͻ11.5g/dl, respectively). Although only a small number of the patients had anemia as defined by normal values, a retrospective analysis of individual patients over time revealed a sustained though small decrease in Hb from initial presentation. A statistically significant difference in Epo levels (P ϭ 0.016 by Kruskal-Wallis test) was observed from the group with the lowest (Hb Յ11.5) to that with the highest (Hb Ն14.5) Hb values, with a median Epo value of 37 (interquartile range 24 -42) vs. 13 (9 -15) IU/l, respectively. In contrast, there was no evidence of an increased reticulocyte response to higher levels of Epo (r ϭ 0.134 [Pearsons], P ϭ 0.36). Reticulocyte counts ranged from 44 (38 -57) to 76.5 (56 -83) in the lowest and highest Hb groups, respectively.CONCLUSIONS -Although only a small number of subjects in the group were overtly anemic, all subjects had an ongoing, small but significant decrease in Hb since presentation. This study of diabetic patients without nephropathy shows an expected increase in Epo production in response to lowering levels of Hb but without the expected reticulocyte response. Diabetes Care 28:1118 -1123, 2005I n the U.K., as in the rest of the Western world, diabetes is the most prevalent cause of renal failure. Over the next 10 years, the number of patients with diabetes and end-stage renal disease is expected to double, causing a significant increase in the burden of care for this patient population (1). Although the prognosis with diabetic nephropathy has improved since early reports (2,3), there remains an excess mortality of 70 -100 times that of an otherwise matched population (4). Survival rates on dialysis remain poor, with up to 33% of patients dying within a year of starting dialysis (4). Furthermore, for patients who require renal replacement therapy, morbidity as assessed by hospitalization is 2-3 times greater than for nondiabetic patients with end-stage renal failure (2). This excess of morbidity and mortality in part relates to the high incidence of cardiovascul...

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

“…The present study therefore extends these findings to diabetic patients with modest renal impairment and normoand microalbuminuria. In diabetes, anaemia, associated with erythropoietin deficiency, appears to occur earlier in the course of progression of kidney disease than in non-diabetic patients with kidney diseases [2][3][4][5][6][7]. Haemoglobin concentrations were found to be significantly decreased in patients with microalbuminuria compared to patients with normoalbuminuria [3].…”

“…However, the precise mechanisms of anaemia in diabetic patients are unknown, and a decline in haemoglobin concentrations appears to occur earlier in diabetic patients with nephropathy than in patients with non-diabetic kidney diseases [2][3][4][5][6][7]. In addition to erythropoietin deficiency due to tubulointerstitial changes, which is an early morphological alteration of diabetic nephropathy [8], autonomic neuropathy [9,10] and increased serum advanced glycation end-products [11] may participate in the pathogenesis of anaemia in diabetic kidney disease.…”

Anaemia in diabetes: is there a rationale to TREAT?

“…2), an early marker of microvascular inflammation and damage [14], which, like anaemia [3], precedes declining renal function associated with late-stage nephropathy. Recently, it has also been shown that, even in the absence of albuminuria, anaemia in patients with diabetes is largely the result of impaired renal functioning [15]. These strong links between the kidney and anaemia in diabetes probably reflect the unique vulnerability of the renal microcirculation to damage in diabetes [16].…”

“…One major factor in the genesis of anaemia is the failure to increase circulating erythropoietin concentrations in response to falling Hb (so-called functional erythropoietin deficiency) [4,15,18,19]. In healthy individuals, any decrease in Hb is normally matched by an exponential increase in renal erythropoietin production.…”

Impact of diabetes on haemoglobin levels in renal disease

“…The relationship between anaemia, diabetes and renal impairment has also been investigated in several small studies [10][11][12]. The Kidney Early Evaluation Study also reported diabetes to be independently correlated with anaemia in persons with moderate reduction in kidney function [13].…”