Use of evidence in hypertension guidelines.

In their review of the use of evidence in hypertension guidelines, Parker and Glasziou point out that failure to measure blood pressure in both arms may lead to delay in diagnosis or inadequate treatment of high blood pressure. However, only 30% of GPs agree with recommendations to measure blood pressure in both arms, and even fewer actually do it. Similarly, it is important to see if patients who take their own blood pressure at home adhere to recommendations, both measuring and recording their readings correctly. Assessing the reliability of patients’ reports of home blood pressure measurements is crucial to see whether self-monitoring can be used by health professionals to provide precise estimates of the true blood pressure. Possible disadvantages of this technique include reporting bias and unsupervised alteration of medication. Newer blood pressure monitors offer the advantages of built-in printers or internal storage of all blood pressure measurements, which can be subsequently downloaded. We are completing recruitment for a Stroke Association funded trial of home blood pressure monitoring in 360 hypertensive stroke patients. Intervention patients are given a blood pressure monitor, shown how to use it, and asked to record their blood pressure once a week taking three readings each time. In Spring 2009 we conducted a pilot study to examine the reliability and accuracy of patients’ blood pressure recordings and the degree to which patients might selectively record readings, working party of the British Hypertension Society. BHS guidelines 2004. http://www.bhsoc.org/Latest_BHS_management_Guid elines.stm (accessed 11 May 2009) 4. Kerry S, Markus H, Khong T, et al. Community based trial of home blood pressure monitoring with nurseled telephone support in patients with stroke or transient ischaemic attack recently discharged from hospital. Trials 2008; 9: 15. 5. Nordmann A, Frach B, Walker T, et al. Reliability of patients measuring blood pressure at home: prospective observational study. BMJ 1999; 319(7218): 1172.