Original Paper

Seasonal Variation in Blood Pressure of Patients on Continuous Ambulatory Peritoneal Dialysis
Li-Tao Cheng^{a, b}, Hong-Ying Jiang^{b, c}, Li-Jun Tang^{b, d}, Tao Wang^{a, b}

Divisions of Nephrology,
^aFirst Hospital and
^bThird Hospital, Peking University, Beijing,
^cDivision of Nephrology, Second Affiliated Hospital of Kunming Medical College, Kunming, and
^dDivision of Nephrology, Qilu Hospital of Shandong University, Ji'nan, China

Address of Corresponding Author

Blood Purif 2006;24:499-507 (DOI: 10.1159/000096077)

  Key Words

• Blood pressure, seasonal variation in
• Meteorology
• Peritoneal dialysis
• Diabetes
• Extracellular water

  Abstract

Background: A seasonal variation in blood pressure (BP) has been observed in hemodialysis and renal transplant patients. However, this phenomenon in continuous ambulatory peritoneal dialysis (CAPD) patients, whose hemodynamics are different from hemodialysis patients, has not been reported before. In addition, the contribution of extracellular water (ECW) in the seasonal variation in BP is not clear. Methods: All stable CAPD patients (n = 122) dialyzed in a single center from January 1, 2003 to December 12, 2004 were studied. Systolic blood pressure (SBP), diastolic blood pressure (DBP), weight and ECW (by bioimpedance analysis) were measured in every patient. Climatic data were obtained from the Beijing Weather Bureau. These data were pooled together and grouped according to the calendar month. Results: In general, an apparent seasonal variation in BP was observed in CAPD patients. BP began to decrease from spring and reached the lowest level in summer, then increased from autumn and reached its peak in winter. The seasonal variation in BP in male patients was similar to that in female patients, but in comparison to non-diabetic patients there was no apparent seasonal variation in the BP of diabetic patients. SBP and DBP negatively correlated with the average atmospheric temperature (r = -0.768, p < 0.001 and r = -0.764, p < 0.001, respectively). BP also negatively correlated with rainfall and humidity, but this correlation disappeared when temperature was controlled in partial correlation analysis. Weight and ECW fluctuated throughout the year but showed no seasonal variation. Conclusion: On the whole there was an apparent seasonal variation in blood pressure in CAPD patients. As opposed to non-diabetic patients, there was no apparent seasonal variation in BP in diabetic patients. The seasonal variation in BP was influenced more by temperature than rainfall and humidity, and the change in ECW was not seasonal, suggesting that other mechanisms such as total peripheral resistance might play a more important role in this phenomenon.

Copyright © 2006 S. Karger AG, Basel

  Author Contacts

Tao Wang, MD, PhD
Division of Nephrology, Third Hospital, Peking University
49 North Garden Rd, Haidian District
Beijing 100083 (P.R. China)
Tel. +86 10 6201 7691 2517, Fax +86 10 6617 0758, E-Mail wangt@bjmu.edu.cn

  Article Information

Received: February 22, 2006
Accepted: June 16, 2006
Published online: October 2, 2006
Number of Print Pages : 9
Number of Figures : 7, Number of Tables : 3, Number of References : 19