Clinical and Laboratory Profile of Patients With Type 2 Diabetes With Low Glomerular Filtration Rate and Normoalbuminuria

The initial evidence of diabetic nephropathy in type 2 diabetic patients is the development of microalbuminuria (1). However, the UK Prospective Diabetes Study demonstrated that 51% of patients who progress to chronic renal failure had no preceding albuminuria (1). Patients with low estimated glomerular filtration rate (eGFR) (<60 ml/min per 1.73 m2) and normoalbuminuria presented an increased rate of cardiovascular disease (2–4) due to unknown reasons. Aggregation of conventional cardiovascular risk factors might play a role. Therefore, the aim of this study was to analyze the clinical and laboratory features of type 2 diabetic patients with low eGFR and normoalbuminuria. A cross-sectional study was performed in all consecutive normoalbuminuric type 2 diabetic patients attending the outpatient clinic at Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil, between 1999 and 2006 with eGFR >15 ml/min per 1.73 m2. Normoalbuminuria was defined by urinary albumin excretion (UAE) values <20 μg/min, <17 mg/l (random sample), or <30 mg in 24 h (5) on at least two occasions over the preceding 6 months while on their usual antihypertensive medication. eGFR was calculated using the Modification of Diet in Renal Disease formula: 186 × [plasma creatinine (mg/dl)−1.154 × age (years)−0.203 × (1.212 if black) × (0.742 if female)] (6). All patients answered a standard questionnaire and underwent physical examination and laboratory tests. Metabolic syndrome was defined according to …