J Hum Hypertens. 2005 May;19(5):381-7.
Naschitz JE, Mussafia-Priselac R, Peck ER, Peck S, Naftali N, Storch S, Slobodin G, Elias N, Rosner I.
1Department of Internal Medicine A, Bnai-Zion Medical Center, Haifa, Israel.
Based on prior studies, the hypothesis that hyperventilation (HV) may have a pressor effect and play a causal role in hypertension has been suggested. The objective of this study was to correlate HV with blood pressure (BP)-change during a postural challenge. Consecutive subjects referred for evaluation of syncope, dizziness, chronic fatigue syndrome (CFS), fibromyalgia, or non-CFS fatigue were assessed with a 10-min supine 30-min head-up tilt test combined with capnography.
We selected for analysis the records of patients aged 17-70 years, not taking vasoactive medications, having sitting systolic BP (SBP)<140 mmHg, sitting diastolic BP (DBP) <90 mmHg, and who completed 30 min of tilt. HV was diagnosed when end-tidal pressure of CO(2) /=10 min. Postural hypertension (PHT) was diagnosed when DBP on tilt >/=90 mmHg was recorded consecutively for >/=10 min. DBP-change was computed as (median DBP on tilt) -(median DBP supine). PHT and DBP-change were correlated with HV. A total of 320 patient charts were reviewed. PHT was present in 30 cases.
The mean DBP-change in patients with PHT was +9.9 mmHg (s.d. 5.8), with three patients manifesting HV. Of the remaining 290 patients, 56 had HV, their mean DBP-change was -0.3 mmHg (s.d. 7.2). The other 234 patients without HV had a mean DBP-change +0.95 mmHg (s.d. 5.7), comparable to the DBP-change in patients with HV.
In, conclusion, posturally induced HV was not associated with an increase in BP, nor was PHT associated with HV, except in a small minority of cases.
Journal of Human Hypertension (2005) 19, 381-387. doi:10.1038/sj.jhh.1001830.
PMID: 15838538 [PubMed – in process]