Ambulatory blood pressure levels for diagnosising and treating hypertension

January 01, 0001

Ambulatory blood pressure levels for diagnosising and treating hypertension

These Australian researchers sought age and gender related ambulatory blood pressure equivalents to clinic blood pressure thresholds related to the diagnosis and treatment of hypertension. They recorded ambulatory blood pressures with validated devices, at 11 sites across Australian (n=8575). They utilized least product regression to compare the ambulatory measurements and clinic blood pressures measured by both trained staff and,in a smaller cohort, by doctors (n=1693).

The researchers found: "Mean age of participants was 56 years with mean body mass index 28.9 and mean clinic systolic/diastolic blood pressure 142/82 mm Hg, and 4626 (54%) were women. Average clinic measurements by trained staff were 6/3 mm Hg higher than daytime ambulatory blood pressure and 10/5 mm Hg higher than 24 hour blood pressure, but 9/7 mm Hg lower than clinic values measured by doctors. Daytime ambulatory equivalents derived from trained staff clinic measurements were 4/3 mm Hg less than the 140/90 mm Hg clinic threshold (lower limit of grade 1 hypertension), 2/2 mm Hg less than the 130/80 mm Hg threshold (target upper limit for patients with associated conditions), and 1/1 mm Hg less than the 125/75 mm Hg threshold. Equivalents were 1/2 mm Hg lower for women and 3/1 mm Hg lower in older people compared with the combined group."

The researchers concluded: "Our study provides daytime ambulatory blood pressure thresholds that are slightly lower than equivalent clinic values. Clinic blood pressure measurements taken by doctors were considerably higher than those taken by trained staff and therefore gave inappropriate estimates of ambulatory thresholds. These results provide a framework for the diagnosis and management of hypertension using ambulatory blood pressure values."

This study elucidates ambulatory blood pressure levels for diagnosing and treating hypertension, and has the intriguing finding of differences in readings obtained by doctors and trained staff.

For the full abstract, click here.

BMJ 340:c1104, 14 April 2010
© 2010 Head et al.
Definition of ambulatory blood pressure targets for diagnosis and treatment of hypertension in relation to clinic blood pressure: prospective cohort study. Geoffrey A Head, Anastasia S Mihailidou, Karen A Duggan, et al. Correspondence to G A Head:

Category: K. Circulatory. Keywords: ambulatory blood pressure, hypertension, threshold, diagnosis, treatment, epidemiologic study, journal watch.
Synopsis edited by Dr Paul Schaefer, Toledo, Ohio. Posted on Global Family Doctor 14 May 2010

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