Normoalbuminuric renal-insufficient diabetic patients: a lower-risk group.
OBJECTIVE
About 20% of diabetic patients with chronic kidney disease (CKD) detected from the new American Diabetes Association recommendations (albumin excretion rate >30 mg/24 h or estimated glomerular filtration rate [GFR] <60 ml/min per 1.73 m2) may be normoalbuminuric. Do the characteristics and outcome differ for subjects with and without albuminuria?


METHODS
A total of 89 patients with diabetes and a modification of diet in renal disease (MDRD) estimated GFR (e-GFR) <60 ml/min per 1.73 m2 underwent a 51Cr-EDTA B-isotopic GFR determination and were followed up for 38 +/- 11 months.


RESULTS
The mean MDRD e-GFR (41.3 +/- 13.1 ml/min per 1.73 m2) did not significantly differ from the i-GFR (45.6 +/- 29.7). Of the subjects, 15 (17%) were normoalbuminuric. Their i-GFR did not differ from the albuminuric rate and from their MDRD e-GFR, although their serum creatinine was lower (122 +/- 27 vs. 160 +/- 71 micromol/l, P < 0.05): 71% would not have been detected by measuring serum creatinine (sCr) alone. They were less affected by diabetic retinopathy, and their HDL cholesterol and hemoglobin were higher (P < 0.05 vs. albuminuric). None of the CKD normoalbuminuric subjects started dialysis (microalbuminuric: 2/36, macroalbuminuric: 10/38) or died (microalbuminuric: 3/36, macroalbuminuric: 7/38) during the follow-up period (log-rank test: P < 0.005 for death or dialysis), and their albumin excretion rate and sCr values were stable after 38 months, whereas the AER increased in the microalbuminuric patients (P < 0.05), and the sCr increased in the macroalbuminuric patients (P < 0.01).


CONCLUSIONS
Although their sCr is usually normal, most of the normoalbuminuric diabetic subjects with CKD according to an MDRD e-GFR below 60 ml/min per 1.73 m2 do really have a GFR below 60 ml/min per 1.73 m2. However, as expected, because of normoalbuminuria and other favorable characteristics, their risk for CKD progression or death is lower.
Rigalleau
Vincent
V
Department of Nutrition-Diabétologie, Hôpital Haut-Lévêque, Avenue de Magellan, 33600 Pessac, France. vincent.rigalleau@wanadoo.fr
Lasseur
Catherine
C
Raffaitin
Christelle
C
Beauvieux
Marie-Christine
MC
Barthe
Nicole
N
Chauveau
Philippe
P
Combe
Christian
C
Gin
Henri
H
D000368:Aged; D000419:Albuminuria; D001786:Blood Glucose / Q000378:metabolism; D003401:Creatine / Q000097:blood; D003928:Diabetic Nephropathies / Q000401:mortality / Q000503:physiopathology / Q000628:therapy / Q000652:urine*; D004032:Diet; D003927:Diet, Diabetic; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D017582:Renal Replacement Therapy; D018570:Risk Assessment; D016019:Survival Analysis
D001786:Blood Glucose; D003401:Creatine