Optimizing heart failure management: an Australian experience.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to Richard MacIsaac.
Explore the source record for details and available documents.
BACKGROUND: Diabetes mellitus is associated with an increased prevalence of anemia, particularly in patients with nephropathy. We undertook this survey to determine the relationship between anemia and the renal production of erythropoietin in patients with diabetes mellitus. METHODS: The clinical data of 722 patients were obtained, including markers of diabetic complications. Erythropoietin levels were measured in the same samples. Patients with a full blood cell count, iron indexes, and renal function within the normal range (n = 151) were used to define the reference range for this population. Anemic patients who had erythropoietin levels within this range were defined as having an "inappropriate erythropoietin response to anemia." RESULTS: Of the 722 patients, 168 (23.3%) had anemia, of whom 130 (77.4%) had erythropoietin levels inappropriately within the normal range. Although 55.4% of anemic patients had moderate renal impairment, erythropoietin levels were also inappropriately low in 69.2% of anemic patients with normal renal function. However, most of these patients (17 of 26) had diabetic kidney disease, as denoted by albuminuria. CONCLUSIONS: The failure to produce erythropoietin in response to a declining hemoglobin level is a common contributor to anemia in patients with diabetes mellitus. This seems to be a manifestation of diabetic kidney disease, in the presence or absence of renal impairment.
Incomplete digestion of advanced glycation end product (AGE)-modified protein results in the formation of low-molecular weight degradation products incorporating AGE modifications (LMW-AGEs). In addition to being biomarkers of AGE modification, LMW-AGEs may have a high toxic potential, being free to interact with AGE receptors at distant sites via the circulation. Several free AGEs have been identified, including pentosidine, N(epsilon)-(carboxymethyl)lysine (CML), and free-imidazole AGEs. In addition, fluorescence (370 nm [excitation]/440 nm [emission]) in the LMW phase of serum correlates with tissue fluorescence, an established marker for AGE modification. In experimental diabetes, LMW fluorescence increases with duration of disease and is normalized with the AGE inhibitor aminoguanidine. LMW fluorescence is also higher in patients with diabetes, in whom it is associated with glomerular filtration rate and hemoglobin. Patients with hyperfiltration have lower LMW fluorescence than those with normal renal function, which may protect them from AGE accumulation in the short term. These findings provide clinical support for the association between AGEs and progressive renal injury in diabetes.
BACKGROUND: Advanced glycation end products (AGEs) are implicated in the development and progression of diabetic nephropathy. We examined the predictors of low-molecular-weight (LMW) AGEs in a cross-sectional survey of 604 patients with type 2 diabetes in a single clinic. METHODS: A clinical history and results of routine blood and urine testing were obtained for all patients over a 2-year period. Fluorescent LMW AGEs were estimated in serum samples taken concurrently, using an established flow injection method. Predictors of LMW AGEs were identified using multiple regression analysis. RESULTS: LMW AGEs were 34% higher in patients with diabetes than nondiabetic volunteers from the same community (P < 0.001). Independent predictors for LMW AGEs in patients with diabetes were glomerular filtration rate (GFR) and hemoglobin (both P < 0.001). While patients with renal impairment and anemia had the highest levels of LMW AGEs, both GFR and hemoglobin remained predictive when patients with a serum creatinine or hemoglobin within the "normal range" were analyzed separately. Patients with hyperfiltration had significantly lower LMW AGEs than those with normal renal function. Gender was also a significant independent predictor of LMW AGEs in patients without anemia. However, LMW AGEs were not associated with metabolic control or the presence of macrovascular disease. CONCLUSION: Circulating levels of LMW AGEs are elevated in patients with diabetes, especially those with impaired renal function or anemia. These findings extend the evidence for an association between AGEs and progressive renal injury in patients with type 2 diabetes. Whether LMW AGEs contribute to, or are a marker of, renal damage needs to be established by prospective studies.