Lipoprotein-associated phospholipase A2 mass and activity in children with heterozygous familial hypercholesterolemia and unaffected siblings: effect of pravastatin.
BACKGROUND
Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an independent risk factor of cardiovascular disease and a target of treatment. Lp-PLA(2) levels in children have not been previously reported. The effect of statin therapy on Lp-PLA(2) mass and activity in children with familial hypercholesterolemia (FH) is also not known.


METHODS
Lp-PLA(2) mass and activity levels were measured at baseline and after 2 years in 178 children with FH randomized to pravastatin or placebo and in 78 unaffected and untreated siblings. At the end of the randomized period, all FH children were then placed on pravastatin for an additional 2 years, and Lp-PLA(2) mass and activity levels were correlated with changes in carotid intima-media thickness during 4 years of follow-up.


RESULTS
Baseline levels of Lp-PLA(2) mass and activity were significantly greater in children with FH compared with unaffected siblings (mass: 240.3 ± 41.6 vs 222.1 ± 36.5 ng/mL, P = .002; activity: 205.7 ± 41.6 vs 124.3±23.0 nmol/min/mL, P < .0001). In the randomized FH cohort, after 2 years treatment, Lp-PLA(2) mass (217.8 ± 35.0 vs 231.5 ± 34.8 ng/mL, P = .001) and activity (178.8 ± 37.3 vs 206.2 ± 33.5 nmol/min/mL, P < .0001) were significantly reduced by pravastatin compared with placebo. Change in Lp-PLA(2) activity was related to change in low-density lipoprotein cholesterol (pravastatin: r = 0.53, P < .0001, placebo: r = 0.23, P < .001) but change in Lp-PLA(2) mass was not related to change in low-density lipoprotein cholesterol. Baseline levels of Lp-PLA(2) mass and activity were not significantly associated with carotid intima-media thickness at baseline or at 4 years.


CONCLUSIONS
Lp-PLA(2) mass and activity are significantly elevated in children with heterozygous FH compared with unaffected siblings and are significantly reduced by pravastatin therapy.
Division of Cardiology, Department of Internal Medicine, Seoul Eulji Hospital, Eulji University, School of Medicine, Seoul, Republic of Korea.
Sung Kee
SK
Ryu
Barbara A
BA
Hutten
Maud N
MN
Vissers
Albert
A
Wiegman
John J P
JJ
Kastelein
Sotirios
S
Tsimikas
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000097:blood*; D000293:Adolescent; D002339:Carotid Arteries / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D004311:Double-Blind Method; D057075:Enzyme Assays; D005500:Follow-Up Studies; D006579:Heterozygote; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D006938:Hyperlipoproteinemia Type II / Q000097:blood / Q000188:drug therapy* / Q000235:genetics; D017035:Pravastatin / Q000627:therapeutic use*; D035781:Siblings; D017539:Tunica Intima / Q000473:pathology
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase; D017035:Pravastatin