[Serum C3 as a screening factor in the primary prevention of myocardial infarct].
This study addresses the possible use of serum C3 (third component of the complement system) to select the subjects to be submitted to diet or drug therapy in the primary prevention of myocardial infarction. C3 is synthesized by macrophages, which are the main cells involved in atheroma formation, and an association between serum C3 and the risk of myocardial infarction has recently been found in the male sex. We have studied 332 men aged 45-75 years, who had no cardiovascular disease at any time before blood sampling. In their sera C3 measurement was performed by nephelometry. The 4 year follow-up was known for all of these subjects: in particular, 11 had a myocardial infarction. The average LDL cholesterol (LDL-C) levels in the whole population were rather high (162.2 +/- 45.8 (1 SD) mg/dl). As standard treatment criteria (A), those suggested for primary prevention by the National Cholesterol Education Program panel of experts were adopted: diet if LDL-C > or = 160 mg/dl, or LDL-C > or = 130 mg/dl + 2 additional risk factors; drugs if, after diet, LDL-C > or = 190 mg/dl, or LDL-C > or = 160 mg/dl + 2 risk factors. This scheme was compared with two models of treatment which included the measurement of serum C3. According to the first of such models (B), diet should be prescribed when C3 levels are within the high third of distribution (> or = 135 mg/dl) with LDL-C > or = 100 mg/dl, and drugs should be given if, after diet, serum C3 is > or = 135 mg/dl with LDL-C > or = 130 mg/dl. The second model based on C3 (C) is of combined type since, in addition to model B criteria, it also suggests to prescribe a diet if LDL-C > or = 190 mg/dl, while drugs should be given if, after diet, LDL-C levels persist > or = 190 mg/dl. The effect of diet has been simulated by assuming a 10% decrease in LDL-C levels. According to all of these criteria, the subjects to treat with diet with the models A, B and C would have been, respectively, 71, 27 (p < 0.0001 vs mod A) and 45% (p < 0.0001 vs mod A) of the whole population, including among them, respectively, 82, 82 and 100% of the future myocardial infarctions. After diet, according to the three models A, B and C -29, 20 (p = 0.0117 vs mod A) and 30% of the whole population should have been treated with drugs, including, respectively, 54, 64 and 82% of the future myocardial infarctions. In conclusion, the use of criteria based on serum C3, with respect to more traditional guidelines, might allow a more precise identification of the subjects to submit to diet and drug treatment in the primary prevention of myocardial infarction.
Istituto di Patologia Speciale Medica e Metodologia Clinica, Università degli Studi, Bologna.
A
A
Muscari
G
G
Massarelli
G M
GM
Puddu
Z
Z
Sangiorgi
A
A
Dormi
M
M
Bagnoli
A
A
Gaddi
P
P
Puddu
D000368:Aged; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000453:epidemiology; D016009:Chi-Square Distribution; D003176:Complement C3 / Q000032:analysis*; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000517:prevention & control; D011322:Primary Prevention; D012307:Risk Factors; D018709:Statistics, Nonparametric
D015415:Biomarkers; D003176:Complement C3
Il C3 sierico come fattore di selezione nella prevenzione primaria dell'infarto miocardico.