Plasma carotenoids and risk of acute myocardial infarction in the Singapore Chinese Health Study.

OBJECTIVE

Modification of low-density lipoprotein due to oxidative stress is essential in the development of coronary atherosclerosis. Data of specific carotenoids except β-carotene on cardioprotective effects in humans are limited.

RESULTS

This study examined the associations between plasma concentrations of specific carotenoids and incidence of acute myocardial infarction. The study included 280 incident cases of acute myocardial infarction and 560 matched controls nested within the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women aged 45-74 years old enrolled in 1993-1998 in Singapore. Retinol and carotenoids in prediagnostic plasma were quantified using high-performance liquid chromatography. High levels of plasma β-cryptoxanthin and lutein were associated with decreased risk of acute myocardial infarction after adjustment for multiple risk factors for coronary heart disease. For β-cryptoxanthin, the odds ratio (95% confidence interval) for the highest (Q5) versus the lowest (Q1) quintile was 0.67 (0.37-1.21) (P for trend=0.03). For lutein, the odds ratios (95% confidence intervals) for the combined Q2-Q3 and the combined Q4-Q5 versus Q1 were 0.71 (0.45-1.12) and 0.58 (0.35-0.94) respectively (P for trend=0.03). There was no statistically significant association between other carotenoids or retinol and risk of acute myocardial infarction.

CONCLUSIONS

High plasma levels of β-cryptoxanthin and lutein were associated with decreased risk of acute myocardial infarction. The findings of this study support a cardioprotective role of these two carotenoids in humans.