Modifiable Risks For The Development of Diabetic Nephropathy Identified

The individual risk of progression to microalbuminuria ranged from roughly 10% in patients with no risk markers to 70% in patients with all four risk markers. 

In a long-term prospective observational study, three factors emerged as significant risk factors for the development of incipient and overt diabetic nephropathy in type 1 diabetics.

All three risk factors--smoking, retinopathy as an indicator of poor glycemic control, and a urinary albumin excretion rate >30 mg per24 hours--are "potentially modifiable," Dr. Peter Rossing from the Steno Diabetes Center, Gentofte, Denmark and colleagues emphasize in their report in the May issue of Diabetes Care.

The Danish team followed 537 patients with type 1 diabetes for 5 years or longer, with normoalbuminuria, defined as a urinary albumin excretion rate of

Urinary albumin excretion rate progressed an average of 7.6% per year, according to the group. During a median followup of 9 years, 25% of patients developed persistent microalbuminuria or macroalbuminuria, defined as >30 mg/24 h in two of three consecutive urine samples.

For Cox multiple regression analysis, the team "arbitrarily chose baseline values above the median for HbA1c (8.6%) and urinary albumin excretion rate (10 mg/24 h) as risk markers for progression to microalbuminuria, in addition to the presence [or] absence of smoking and diabetic retinopathy," they explain.

Based on the presence or absence of these four risk markers, the individual risk of progression to microalbuminuria ranged from roughly 10% in patients with no risk markers to 70% in patients with all four risk markers. The authors say these risk estimates can be used to guide individual intervention strategies as well as to plan primary prevention trials.

Sex, duration of diabetes, arterial blood pressure, serum creatinine, height and social class did not emerge as risk factors for progression to diabetic nephropathy.  Diabetes Care 2002;25:859-864.