Antioxidant status, erythrocyte fatty acids, and mortality from cardiovascular disease and Keshan disease in China.

OBJECTIVE

Various measures of antioxidant status were investigated in relation to mortality from cardiovascular disease (CVD: coronary heart disease, hypertensive heart disease, and stroke) and Keshan disease.

DESIGN

Ecological study.

SETTING

Sixty-five largely rural counties in the People's Republic of China.

SUBJECTS

One hundred subjects in each county randomly selected from two communes (6500 subjects).

INTERVENTIONS

Antioxidants, antioxidant enzymes, and pro-oxidants were measured from sex- and commune-specific pooled blood samples in each county. Fatty acid content of red blood cells was measured. Mortality rates were determined from a national mortality survey.

RESULTS

In univariate analysis most correlations between measures of antioxidant status and mortality rates from CVD were not statistically significant, although plasma ascorbic acid, beta-carotene and retinol were consistently inversely associated with CVD mortality rates. There were significant negative associations between plasma ascorbic acid and mortality from stroke (r = -0.38, P < 0.01), and plasma selenium and mortality from Keshan disease (r = -0.32, P < 0.05). There was a significant positive association between plasma copper and mortality from hypertensive heart disease (r = 0.32, P < 0.05). Data previously reported from this population demonstrated an inverse association between red blood cell monounsaturated fatty acids and mortality from CVD, and a direct association between red blood cell polyunsaturated fatty acids and mortality from CVD.

CONCLUSIONS

Mortality from CVD and Keshan disease is associated with the fatty acid content of red blood cells and some measures of antioxidant status in blood. It is postulated that the associations between fatty acids and CVD may be related to the different susceptibilities of the respective fatty acids, contained in low-density lipoprotein, to oxidation.