Format

Send to

Choose Destination
Am J Cardiovasc Dis. 2012;2(2):111-5. Epub 2012 May 15.

Seasonal variation of endothelium-dependent flow-mediated vasodilation measured in the same subjects.

Abstract

BACKGROUND:

Seasonal variation of flow-mediated vasodilation (FMD) remains controversial. A large cohort study showing that FMD was highest in summer and lowest in winter has been performed in a cross-sectional manner on different populations in different seasons, and the results for the same population were not compared.

METHODS:

FMD was compared between the cool season (14.4 ± 4.4°C) and warm season (28.8 ± 1.0°C) in the same 27 outpatients with hypertension, diabetes mellitus and/or hyperlipidemia.

RESULTS:

The mean resting brachial artery diameter was significantly larger in the warm season than in the cool season. The maximal post-deflation brachial artery diameter was also significantly larger in the warm season than in the cool season. FMD, which was calculated from the resting diameter and the maximal diameter, was significantly higher in the warm season than in the cool season even when expressed as the relative value (4.74 ± 2.15 vs. 5.71 ± 2.17%, p=0.03) or absolute value (0.18 ± 0.08 vs, 0.23 ± 0.07 mm, p=0.008).

CONCLUSIONS:

FMD was significantly higher in the warm season than in the cool season when the measurements were performed on the same subjects and a paired comparison was made.

KEYWORDS:

Flow-mediated vasodilation; seasonal variation

PMID:
22720200
PMCID:
PMC3371618

Supplemental Content

Full text links

Icon for PubMed Central
Loading ...
Support Center