CORRELATION OF BLOOD-PRESSURE WITH PLASMA ASCORBIC-ACID

In a nutrition survey of 247 Chinese Americans (38% men and 62% women) aged 60-96, the mean plasma ascorbic acid was found to be lower than that of white Americans. The association between their blood pressure and plasma ascorbic acid was explored by analysis of covariance and multiple regression, adjusting for age, sex, body mass index, alcohol and cigarette consumption, dietary Na:K ratio, serum Ca:P ratio and physical activity level. Inverse associations were observed between plasma ascorbic acid and systolic blood pressure (p < .001) and diastolic blood pressure (p < .001). Subjects in the lowest quartile of plasma ascorbic acid had a mean systolic blood pressure which was 17.6 mm Hg higher than those in the highest quartile; their mean diastolic blood pressure was higher by 5.5 mm Hg. We speculate that subclinical vitamin C deficiency may be a risk factor for hypertension in Chinese Americans.