[Prevalence of "hidden" renal failure in the population suffering from type-2 diabetes]

To determine the prevalence of renal failure (RF) in type-2 diabetics and to compare two criteria of definition: that based on the calculation of glomerular filtration by the Cockcroft-Gault formula corrected for body surface area and that based on serous creatinine.

Cross-sectional, descriptive study.

El Cristo Health Centre, Oviedo, north of Spain.

All patients in the catchment area diagnosed with type-2 diabetes.

Demographic, clinical, risk factor, and cardiovascular pathology details were gathered. Renal failure was diagnosed on figures of plasma creatinine >=1.3 mg/dL in women and >=1.4 mg/dL in men, and glomerular filtration (GF) calculated by means of the Cockcroft-Gault formula: moderate GF, 60-30 mL/min/1.73 m2; severe GF, 29-15 mL/min/1.73 m2, and terminal GF: <15 mL/min/1.73 m2.

499 patients were included. 52.3% were women, aged 69.7+/-10.4 years old. Prevalence of RF by serous creatinine was 12%; and by the Cockcroft-Gault formula, 40.5%. Patients with lower glomerular filtration and normal creatinine were older (75.5+/-7.9 vs 65.4+/-9.8; P<.001), mainly female (76.3% vs 41.7%; P<.001), had lower BMI (27.3+/-3.7 vs 30.9+/-4.4) and had worse glucaemia control (HbA1c 7.1+/-1.8% vs 6.9+/-1.9%; P=.007) and higher indices of cardiac failure (6.4% vs 2.1%; 95% CI, 1.1-8.8; P=.02) than patients with normal glomerular filtration and creatinine.

Calculation of glomerular filtration by the Cockcroft-Gault formula corrected for body surface area revealed unknown renal failure in 1 in 3 type-2 diabetes patients.