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Updated: Aug 17, 2026

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Published on: July 19, 2011
Patient and environmental factors affecting ambulatory blood pressure monitoring
1Department of Medicine, Sunnybrook Health Science Centre, Toronto, Ontario.
Abstract:
Several patient and environmental factors may limit the applicability of ambulatory BP monitoring. In children and in elderly patients, erroneous readings may occur more frequently. Comparison of 25 elderly (greater than 65 yr) vs 25 young subjects recently monitored for clinical reasons in our hypertension clinic showed slightly higher error rates (19% vs 15% of readings) in the elderly but similar willingness to undergo monitoring again (96% vs 84% of subjects, respectively). The technique has not been well validated in obesity. Arrhythmias may prevent currently available ambulatory BP machines from obtaining usable readings. Monitoring may prove unsatisfactory for patients engaged in physically active occupations, travelling in automobiles, or in environments where the noise of the ambulatory BP machine would be disruptive. Portable automatic monitors can detect abnormally elevated average BP during sleep but the diagnostic value of this pattern remains unknown. It is concluded that ambulatory BP monitoring may be successfully performed in most patients.
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