Response to Is Siesta Masking Masked Hypertension?
As discussed in our article,1 there are large differences in the prevalence of office resistance and isolated office control depending on many factors, for example, age. White-coat hypertension increases with age, and the opposite is true for masked hypertension, and mean age in our sample was 61.9±12.3 years. But our results are not unique. Methodologic differences aside, in our study, as in the Pressione Arteriose Monitorate E Loro Associazioni Study in Italy, the white-coat condition was much more common than the reversed phenomenon.3
In our study, the mean “daytime” ambulatory blood pressure (BP) was used as the reference standard for analysis, because we tried to compare it with office BP,1 which was obviously determined during the day. Office BP control (<140/90 mm Hg) was 23.6%, and 51.6% of patients were controlled (<135/85 mm Hg) according to daytime ambulatory BP monitoring.1 However, we recognize that BP control is also important during nighttime. As Ben-Dov and Bursztyn have suggested,2 we have analyzed office BP values against 24-hour ambulatory BP monitoring data. The mean of 24-hour BP control (<130/80 mm Hg)4 was 44.3%, a figure lower than daytime BP control but still quite higher than office BP control.
In our study,1 we considered BP during the daytime (awake period) and nighttime (asleep period) from subject diaries, but daytime napping (siesta) was not excluded in the analyses done. However, most siestas take <1 hour in Spain, and, thus, only 1 or 2 BP measurements out of many readings per day should be removed in calculating daytime (awake) ambulatory BP. The influence of removing siesta BP on daytime ambulatory BP would, thus, probably be small. Furthermore, from a clinical point of view, the influence of siesta on average BP of the wakeful period seems to be small.5 However, as Ben-Dov and Bursztyn suggest,2 using 24-hour ambulatory BP would serve to overcome the issue of the influence of siesta.
Overall, the encouraging message to physicians remains: they are doing better in BP control than is believed based on office surveys, regardless of whether ambulatory BP was determined during the daytime or for 24 hours. Although we acknowledge that any difference in the schedule of ambulatory BP monitoring used will affect the resulting BP control, 24-hour ambulatory BP monitoring in our study reveals that true (ambulatory) BP control is almost double the office BP control figure.
We thank all those physicians-members of the Spanish Society of Hypertension ABPM Registry who participated in this study. The names of all participating practitioners have been previously published and are available online at http://www.cardiorisc.com.
Source of Funding
The main funding for the study was obtained from Lacer Spain, S. A. through an unrestricted educational grant. The funding body had no role in study design, analysis and interpretation of data, writing the report, or the decision to submit the paper for publication.
Banegas JR, Segura J, Sobrino J, Rodríguez-Artalejo F, Sierra A, Cruz JJ, Gorostidi M, Sarría A, Ruilope LM. Effectiveness of blood pressure control outside the medical setting. Hypertension. 2007; 49: 62–68.
Ben-Dov IZ, Bursztyn M. Is siesta masking masked hypertension? Hypertension. 2007; 49: e25.
Bombelli M, Sega R, Facchetti R, Corrao G, Friz HP, Vertemati AM, Sanvito R, Banfi E, Carugo S, Primitz L, Mancia G. Prevalence and clinical significance of a greater ambulatory versus office blood pressure (“reversed white coat” condition) in a general population. J Hypertens. 2005; 23: 513–520.
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