Potential hypotensive effects of Umezu polyphenols: a 14-week community-based, double-masked and placebo-controlled trial.

OBJECTIVE: To evaluate blood pressure (BP)-lowering effects of Umezu polyphenols, polyphenols contained in Japanese plums, in a community-based sample by double-masked and placebo-controlled design. METHODS: Seventy-two Japanese community-dwellers who were interested in prevention or control of their BP (preferably high-normal BP or grade I hypertension) but without antihypertensive medication were randomized into Umezu polyphenols or placebo groups. Each subject took 800 mg/day of Umezu polyphenols or placebo for 12 weeks, followed by a 2-week washout period. Their home and office BP were monitored for 14 weeks in a double-masked manner. We analyzed 56 subjects who met the inclusion criteria. RESULTS: Home BP increased gradually in both the groups during the intervention period, while diastolic office BP insignificantly decreased in the intervention group. During the washout period, home systolic BP in the morning elevated only in the intervention group. CONCLUSIONS: The study failed to collect consistent evidence of a clear persistent hypotensive effect of Umezu polyphenols.

Associations between anthropometric factors and peripheral neuropathy defined by vibrotactile perception threshold among industrial vibrating tool operators in Japan.

OBJECTIVES: The effect of anthropometric factors on the fingertip vibrotactile perception threshold (VPT) of industrial vibrating tool operators (IVTOs) is not well known. The purpose of this study was to investigate the associations between anthropometric factors and fingertip VPT. METHODS: We included for analysis two groups of IVTOs: Group 1, predominantly forestry workers (n=325); and Group 2, public servants (n=68). These IVTOs regularly received medical examinations to evaluate hand-arm vibration syndrome. In the examination, measurements of their fingertip VPTs were taken before and after cold-water immersion (10 minutes at 10°C for Group 1 and 5 minutes at 12°C for Group 2). Their body height and weight were measured to calculate the body mass index (BMI). The presence of peripheral neuropathy (PN) was defined as a VPT ≥17.5 dB at 10 minutes after finishing immersion. RESULTS: In the univariate analysis, weight and BMI were associated with a decreased risk of PN in both Groups 1 and 2. The negative association between BMI and PN remained in the multivariate analysis consistently, but weight reached marginal significance only in the multivariate analysis without BMI in both the groups. Age was positively associated with PN consistently in Group 1 but not in Group 2. Years exposed to vibration showed positive association with PN only in the univariate analysis of Group 1. CONCLUSIONS: Among IVTOs, factors reflecting body heat production, such as weight and BMI, were associated with a decreased risk of VPT-defined PN, regardless of the task engaged.