Arterial stiffness is related to augmented seasonal variation of blood pressure in hypertensive patients.
BACKGROUND
Seasonal variation in blood pressure (BP), a usual tendency of both systolic (SBP) and diastolic BP (DBP) to rise during winter in hypertensive patients, may be related to the higher cardiovascular mortality in winter. However, it is not yet clear what factors are relevant to the seasonal BP changes. We hypothesized that arterial stiffness is related to the BP changes between summer and winter.


RESULTS
Eighty-five elderly (>55 years) patients with essential hypertension (33 males, 64+/-6.0 years) were enrolled. Seasonal BP profiles over at least 2 years were studied along with arterial stiffness and clinical variables (age, gender, smoking, duration of hypertension, anti-hypertensive medications and body mass index). Both SBP and DBP were significantly higher during winter compared with three other seasons (spring 128+/-10.0/79+/-7.3 mmHg, summer 127+/-9.8/78+/-7.1 mmHg, autumn 127+/-10.3/78+/-8.0 mmHg, winter 136+/-12.5/81+/-7.6 mmHg; SBP changes; p<0.001, DBP changes; p<0.001). There were no significant seasonal differences among spring, summer and autumn. Pulse wave velocity (PWV), a widely used clinical indicator of arterial stiffness was correlated with winter-summer differences in SBP (r = 0.272, p = 0.012), but not in DBP (r = 0.188, p = 0.085). Age, which was correlated with PWV strongly (p<0.001), was not significantly related to the seasonal changes in BP (SBP changes; p = 0.114, DBP changes; p = 0.298). No other clinical variables had significant correlation with seasonal BP changes. Multivariate regression analysis revealed that PWV is the only significant predictor for winter-summer SBP changes.


CONCLUSIONS
Our results established a feasible link between arterial stiffness and seasonal BP variation. These findings may partly explain higher cardiovascular risk in patients with increased arterial stiffness.
Division of Cardiology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
Jong-Chan
JC
Youn
Se-Joong
SJ
Rim
Sungha
S
Park
Young-Guk
YG
Ko
Seok-Min
SM
Kang
Donghoon
D
Choi
Jong-Won
JW
Ha
Yangsoo
Y
Jang
Namsik
N
Chung
D000368:Aged; D001158:Arteries / Q000503:physiopathology*; D001794:Blood Pressure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000401:mortality / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011674:Pulse; D012307:Risk Factors; D012621:Seasons