The prevalence and risk factors associated with the onset of diabetic nephropathy in juvenile-onset (insulin-dependent) diabetics diagnosed under the age of 17 years in Leicestershire 1930-1985.

The prevalence of diabetic nephropathy was studied in a population of 847 juvenile-onset (insulin-dependent) diabetics diagnosed under the age of 17 years who attended diabetic clinics in Leicestershire between 1930 and 1985. Seven hundred and eighty-nine patients (93.2 per cent) were traced. Eight patients with non-diabetic proteinuria and four classified as maturity-onset diabetics of the young were excluded from further analysis. The mean age at onset was 9.3 +/- 4.2 years (mean +/- SD) and the mean duration of diabetes 17.0 +/- 10.6 years (range 3-63 years). Overall, 28 patients (3.6 per cent) developed persistent proteinuria and 39 patients (five per cent) intermittent proteinuria. End-stage renal failure developed in eight patients. In patients with diabetes of 20 years duration (n = 254) the prevalence of persistent proteinuria was 9.1 per cent and of intermittent proteinuria, 7.9 per cent. Systolic and diastolic blood pressures were elevated in diabetics with persistent proteinuria compared to patients without proteinuria (154/89 +/- 27/15 vs 123/76 +/- 15/9 mm Hg mean +/- SD; p less than 0.001). Systolic blood pressure was also raised in patients with intermittent proteinuria (133/77 +/- 17/12, p less than 0.005). In addition, proteinuria (intermittent and persistent) was significantly associated with the use of once-daily insulin therapy in childhood and poor clinic attendance. This study suggests that twice-daily insulin therapy from diagnosis in childhood and regular contact with the diabetic clinic decreased the prevalence of diabetic nephropathy in this population.