A Case-control Pilot Study on n-3 Polyunsaturated Fatty Acid as a Negative Risk Factor for Myocardial Infarction

Abstract

SUMMARYThe relation between n-3 polyunsaturated fatty acid (PUFA) and nonfatal myocardial infarction is still controversial.A multicenter case-control pilot study on n-3 PUFA as a negative risk factor for myocardial infarction was performed in Niigata prefecture. Seventy-three patients with acute myocardial infarction (AMI) and age and gender matched controls (n = 84) were recruited. Serum leptin levels were significantly higher in patients with AMI than the controls (8.1 ± 6.7 ng/mL versus 5.8 ± 3.7 ng/mL, P < 0.01), and serum high-density lipoprotein cholesterol (HDLc) levels were significantly lower in patients with AMI than the controls (46 ± 10.5 mg/dL versus 60 ± 15 mg/dL, P < 0.00001). Statistically significant differences were preserved in leptin and HDLc when the data were analyzed separately by gender. Serum levels (%weight) of linolenic acid (C18:3:n3), eicosapentaenoic acid (C20:5:n3), docosapentaenoic acid (C22:5:n3), and total n-3 PUFA were significantly lower in patients with AMI than the control group (P < 0.000001, < 0.05, < 0.05, < 0.05, respectively). The serum n-3 PUFA/saturated fatty acid (SF) ratio and n-3 PUFA/n-9 monounsaturated fatty acid (MUFA) ratio were significantly lower in patients with AMI than the controls (P < 0.05 and < 0.01, respectively). When the subjects were separated into two categories according to an n-3/n-6 PUFA ratio below 0.3 or above 0.3, patients with AMI were more frequently in the former while the controls were more frequently in the latter (P < 0.05).N-3 PUFA may be a negative risk factor for AMI. The results suggest leptin is a risk factor for AMI irrespective of ethnicity and gender. (Int Heart J 2005; 46: 583-591)

Relationships Between Serum Unsaturated Fatty Acids and Coronary Risk Factors Negative Relations Between Nervonic Acid and Obesity-Related Risk Factors

“…[31][32][33] Guallar, et al reported that there was no difference in plasma fish oil levels between patients with myocardial infarction and the control in a prospective nested case-control study (the Physician's Health Study), 31) while Tavani, et al showed in their case-control study that n-3 PUFA was inversely related to nonfatal myocardial infarction. 33) We reported that n-3 PUFA may be negatively related to nonfatal myocardial infarction and the optimal n-6/n-3 PUFA ratio may be lower than 3/1 in a case-control study 9) conducted in Japan where the incidence of myocardial infarction is low and the mean ratio of n-6/n-3 PUFA is about 3/1. Siscovick, et al suggested a possible threshold for n-3 PUFA intake (the equivalent of one fatty fish meal a week) for a marked reduction in cardiac sudden death.…”

“…34) We suggest another higher possible threshold for a reduction in nonfatal myocardial infarction, because the protective effects of n-3 PUFA from nonfatal myocardial infarction are obscure in Western cultures where n-3 PUFA intake is very low, 29,31,32) whereas these effects may be evident in epidemiological studies comparing different (in regard to fish consumption) ethnic groups 35) and the protective effect was observed at very high levels of n-3 PUFA compared to those in Western cultures in our previous study. 9) NA, as well as DHA, is well-known as a major component of brain phospholipids, and has been suggested as a therapeutic supplement for demyelinating diseases by some investigators. 36) However, it is catabolized in peroxisomes as are other very long chain fatty acids, and this process is defective in some demylinating diseases, so, the efficacy of dietary NA therapy has been questioned by others.…”

“…Subjects: Thirty-one males (age, 41-78 years) and 11 females (age, 54-77 years) without an existing or history of overt atherosclerotic cardiovascular disease, or overt diabetes mellitus who were enrolled in the control group in a previous casecontrol study on n-3 PUFA as a negative risk factor for myocardial infarction, 9) were the subjects in the present study. Written informed consent was obtained from all subjects and the ethics committee of all hospitals approved the study.…”

Nutrition as a Vehicle for Cardiovascular Translational Research

“…Is there a potential for this nutritional research to be translated into effective preventive medicine applications for the general public? ALA ingestion can impact primary cardiovascular endpoints like morbidity and mortality due to a myocardial infarction in large sample populations over multi-year follow-up studies [22][23][24][25][26][27][28][29][30]. The National Heart, Lung, and Blood Institute Family Heart Study (NHLBI-FHS) showed that an ALA rich diet is associated with a lower prevalence of calcified atherosclerotic plaque in coronary arteries [26].…”

“…Baylin et al [24] reported an inverse relation between ALA in adipose tissue and non-fatal acute myocardial infarction. Oda et al [25] demonstrated that serum levels of ALA, EPA, DHA, and total n−3 polyunsaturated fatty acids (PUFA) were significantly lower in patients with acute myocardial infarction in comparison to the control group. The Health Professionals Follow-up Study investigated 43,757 health professionals aged 40 to 75 years of age who were free of diagnosed cardiovascular disease or diabetes.…”