Sir.—Drs Chase and Glasgow, in their report to the Journal (130:1113, 1976), found a statistically significant increase in serum low-density lipoprotein (LDL or β-lipoprotein in patients with juvenile diabetes mellitus in comparison with normal children.
We had the opportunity to study β-lipoprotein serum concentration in 43 patients (17 boys and 26 girls), aged 5 to 18 years, with juvenile diabetes mellitus in good clinical control (nocturnal hypoglycemia and diabetic ketoacidosis did not occur in the last six months and they were between the tenth and 90th percentile for normal weight and height), in 143 of their siblings (73 boys and 70 girls), aged 5 to 25 years, and in 100 healthy children (52 boys and 48 girls), aged 8 to 14 years, without first-degree relatives with diabetes mellitus. Blood samples were taken after overnight fast and the serum tested in radial immunodiffusion technique using commercial plates.
Comparison of mean values