The Apo A, B, a of coronary risk: back to kindergarten

Abstract

Approximately 1% of the population have a dominantly inherited lipid disorder predisposing to premature vascular disease. Apolipoproteins (Apo) B, and A1, the carrier proteins for the atherogenic low density lipoprotein (LDL) and the protective high density lipoprotein (HDL) cholesterol respectively are markers for these disorders, as is Apo(a), the unique carrier protein for lipoprotein(a). We assessed changes in these apolipoproteins during the first 12 years of life, aiming to detect young families with inherited dyslipidaemia and implement early prevention. Among 1032 consecutively born babies in whom levels were measured within their first week and at a mean age of 8.5 months, the Apo B/A1 ratio and Apo(a) both tracked closely (p < 0.01 and < 0.0001). High B/A1 ratios (> 95 percentile) identified two families with familial hypercholesterolaemia, and infants with high Apo B identified two families with hyperapolipoprotein B. Apo(a) levels increased twofold between the first week and 8.5 months and were highly correlated (r = 0.73, p < 0.0001). Levels at 8.5 months were not different from parental values and were closely correlated with them. We then assessed school children aged eight to 12 years. In a pilot study (n = 1400) we have established normal apolipoprotein values and distribution patterns and defined the 95th percentile for each. This study is continuing and parents of children with high levels are being recalled (with their children) for lipid measurements. Our findings indicate that our approach is feasible and has wide acceptance, and that measuring Apo B/A1 and Apo(a) in childhood identifies families at increased cardiovascular risk. We have yet to assess the efficacy of our family-based coronary prevention programme.