Decennial change of pulse wave velocity and serum carotenoids: the Mikkabi study
METHODS: Data were derived from a health survey of residents of Mikkabi Town, Japan in 2003 and 2013. Production of mandarin orange, which is rich in beta-cryptoxanthin and beta-carotene, is the key industry of Mikkabi. All study subjects gave their written informed consent. Serum concentrations of six carotenoids were examined using a high-performance liquid chromatography system. The baPWV was assessed with a fully automatic device (FORM: OMRON HEALTHCARE Co., Ltd., Japan). The difference of baPWV between 2013 and 2003 was divided into two using a median. Odds ratios for a higher difference of baPWV with tertile of baseline serum carotenoids (1st tertile: reference) were obtained using logistic regression analysis adjusting for sex, age, body mass index, systolic blood pressure, total cholesterol, triglycerides, fasting blood sugar, smoking status, and medication of hypertension, hyperlipidemia and diabetes.
RESULTS: In the 2013 survey, 102 men and 289 women were reexamined for baPWV from 297 men and 579 women who were examined in the 2003 survey. Serum concentration of beta-cryptoxanthin (median: 0.86 μg/ml) was the highest and that of beta-carotene was the second highest (0.35 μg/ml) among the six carotenoids. Odds ratio (95% confidence interval) for higher difference of baPWV was 0.72 (0.43-1.22) in the 2nd tertile and 0.71 (0.42-1.23) in the 3rd tertile of beta-cryptoxanthin, and 1.02 (0.59-1.76) in the 2nd tertile and 0.82 (0.46-1.44) in the 3rd tertile of beta-carotene. None of the six carotenoids showed a statistically significant association with decennial change of baPWV.
CONCLUSIONS: The protective effect of beta-cryptoxanthin on decennial baPWV change was expected, but did not reach statistical significance.