Absolute level and rate of change of albuminuria over 1 year independently predict mortality and cardiovascular events in patients with diabetic nephropathy

• Published in: Diabetic medicine Vol. 20; no. 4; pp. 277 - 282
• Main Authors: Yuyun, M. F., Dinneen, S. F., Edwards, O. M., Wood, E., Wareham, N. J.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01-04-2003; Blackwell
• Subjects: Adult; albuminuria; Albuminuria - etiology; Associated diseases and complications; Biological and medical sciences; cardiovascular disease; Cardiovascular Diseases - complications; Cohort Studies; diabetes mellitus; Diabetes. Impaired glucose tolerance; Diabetic Neuropathies - complications; Diabetic Neuropathies - mortality; Diabetic Neuropathies - urine; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Female; Humans; Male; Medical sciences; Middle Aged; mortality; nephropathy; Predictive Value of Tests; Endocrinopathy; Kidney disease; Human; Urine; Immunopathology; Urinary system disease; Prognosis; Annual variation; Mortality; Albumin; Variations; Autoimmune disease; Cardiovascular disease; diabetes mellitus; Non insulin dependent diabetes; albuminuria; Nephropathy; Follow up study; Insulin dependent diabetes; Complication; Predictive factor
• ISSN: 0742-3071; 1464-5491
• DOI: 10.1046/j.1464-5491.2003.00940.x

Aims To determine the nature of the association between baseline albuminuria and risk of all‐cause mortality and cardiovascular disease, and to determine if the rate of change of albuminuria from baseline over 1 year predicts these endpoints in patients with diabetic nephropathy.
Methods Cohort study of 427 patients (161 Type 1 and 266 Type 2) with diabetic nephropathy defined as urinary albumin excretion (UAE) ≥ 30 mg/24 h at baseline (mean age 53.4 years). Patients were recruited at the time of referral to a diabetic nephropathy clinic and followed up annually for an average of 5 years. UAE rate was re‐measured at 1 year and the rate of change from baseline calculated.
Results All‐cause mortality and cardiovascular disease increased significantly and continuously across quintiles of baseline UAE (P for linear trend < 0.001 in both outcomes). The rate of change of albuminuria over 1 year (log10) independently predicted all‐cause mortality (hazard ratio (95% confidence interval) 1.76 (1.39, 3.11)) and cardiovascular mortality (1.57 (1.13, 5.22)). Taken as a categorical variable, a rate of change of albuminuria ≥ 30% independently predicted mortality and cardiovascular events (2.07 (1.5, 4.30) and 1.89 (1.33, 4.06), respectively).
Conclusions The rate of change of albuminuria over 1 year independently predicts mortality and cardiovascular disease in diabetic nephropathy and may have clinical utility as a risk marker in identifying a subgroup of patients at particular risk. The risk of these outcomes is continuous across the range of baseline albuminuria in patients with diabetic nephropathy.