alpha-carotene and Myocardial-Infarction

Increased intake of carotenoids and vitamin E may protect against myocardial infarction (MI). However, prospective data on blood levels of carotenoids other than beta-carotene and vitamin E (tocopherol) and risk of MI are sparse.. We conducted a prospective, nested case-control analysis among male physicians without prior history of cardiovascular disease who were followed for up to 13 years in the Physicians' Health Study. Samples from 531 physicians diagnosed with MI were analyzed together with samples from paired control subjects, matched for age and smoking, for 5 major carotenoids (alpha- and beta-carotene, beta-cryptoxanthin, lutein, and lycopene), retinol, and alpha- and gamma-tocopherol. Overall, we found no evidence for a protective effect against MI for higher baseline plasma levels of retinol or any of the carotenoids measured. Among current and former smokers but not among never-smokers, higher baseline plasma levels of beta-carotene tended to be associated with lower risk (P for interaction=0.02). Men with higher plasma levels of gamma-tocopherol tended to have an increased risk of MI (P for trend=0.01).. These prospective data do not support an overall protective relation between plasma carotenoids or tocopherols and future MI risk among men without a history of prior cardiovascular disease.

Topics: Adult; Aged; Aged, 80 and over; alpha-Tocopherol; beta Carotene; Carotenoids; Case-Control Studies; Comorbidity; Cryptoxanthins; Follow-Up Studies; gamma-Tocopherol; Humans; Lutein; Lycopene; Male; Middle Aged; Myocardial Infarction; Physicians; Prospective Studies; Risk; Risk Assessment; Smoking; Tocopherols; United States; Vitamin A; Xanthophylls

A multicenter case-control study was conducted to evaluate the relations between antioxidant status assessed by biomarkers and acute myocardial infarction. Incidence cases and frequency matched controls were recruited from 10 European countries to maximize the variance in exposure within the study. Adipose tissue needle aspiration biopsies were taken shortly after the infarction and analyzed for levels of carotenoids and tocopherols. An examination of colinearity including all covariates and the three carotenoids, alpha-carotene, beta-carotene, and lycopene, showed that the variables were sufficiently independent to model simultaneously. When examined singularly, each of the carotenoids appeared to be protective. Upon simultaneous analyses of the carotenoids, however, using conditional logistic regression models that controlled for age, body mass index, socioeconomic status, smoking, hypertension, and maternal and paternal history of disease, lycopene remained independently protective, with an odds ratio of 0.52 for the contrast of the 10th and 90th percentiles (95% confidence interval 0.33-0.82, p = 0.005). The associations for alpha- and beta-carotene were largely eliminated. We conclude that lycopene, or some substance highly correlated which is in a common food source, may contribute to the protective effect of vegetable consumption on myocardial infarction risk.

Topics: Adipose Tissue; beta Carotene; Biomarkers; Carotenoids; Case-Control Studies; Europe; Humans; Hypertension; Israel; Logistic Models; Lycopene; Male; Middle Aged; Myocardial Infarction; Obesity; Odds Ratio; Prevalence; Risk Factors; Smoking