chanes in blood pressure

[Guest guest]

Office Blood Pressure Readings Result in Incorrect Diagnoses & Treatment

Changes 81% of the Time

Blood pressure readings taken in clinical settings may lead to inaccurate

diagnoses as much as 81% of the time, according to research presented at the

American

Academy of Family Physicians (AAFP) 2010 Scientific Assembly....

Advertisement

1089869/4-Lantus_Oad_0_300x250_Gif_0

Steve Burgess, MD, Texas Tech University Health Sciences Center, Amarillo,

Texas, headed the study that investigated the impact of closely following

the

standard guidelines for blood pressure diagnosis and treatment (American

Heart Association [AHA] and The Seventh Report of the Joint National

Committee

on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure

[JNC-7]).

Dr. Burgess and his research team initiated the testing project after

learning of a study in which 172 physicians and nurses were evaluated for

blood pressure

technique and all failed to follow the AHA guidelines for measuring blood

pressure in a clinical setting.

" The JNC-7 lists improper blood pressure measurement as one of the leading

causes of resistant hypertension, " explained Dr. Burgess, " which led us to

question

how much blood pressure changes when pressures are retaken according to the

published guidelines, [and] we saw dramatically different results when we

followed

the guidelines. These changes can make a significant difference in how

doctors manage their patients. "

The current study was conducted at the Texas Tech University Health Sciences

Center. Subjects had to have a systolic blood pressure reading over 120 mm

Hg and/or a diastolic reading over 80 mm Hg and be over 18 years of age.

Individuals experiencing " significant, acute pain " and those in emotional or

respiratory

distress were excluded from the study. In all, 56 subjects were included in

the initial subject group.

Blood pressures were retaken following published AHA and JNC-7 guidelines,

including ensuring that the cuff fit properly, there was no restrictive

clothing,

the patient sat for 5 minutes in a chair with back support, the patient had

their feet firmly planted on the floor and legs uncrossed, the middle of the

cuff was located at mid-sternum for the patient, the patient had had no

caffeine and had not smoked or exercised for 30 minutes, and 2 separate

readings

were taken and then averaged, with a third reading taken if the first 2

differed by over 5 mm Hg.

Dr. Burgess noted that the only AHA/JNC-7 recommendation to which the group

did not adhere involved his team's decision to use " validated, calibrated

machines "

to take the blood pressure rather than using auscultatory technique. He

pointed out, however, that this removed the variable from the study of

different

individuals possibly taking blood pressures slightly differently.

" Over half [56.4%] of the patients changed JNC-7 classifications upon having

their blood pressure taken according to these guidelines, " pointed out Dr.

Burgess. In fact, average systolic pressures fell 15.7 mm Hg (P <.0001) and

average diastolic pressures fell 8.2 mm Hg (P <.0001) when the AHA and JNC-7

recommendations were followed, he added. Initial blood pressure averaged

146.4/87.6 mm Hg, then fell to 130.7/79.4 mm Hg under " proper measurement

techniques "

(P <.0001).

These differences led to some fairly dramatic changes in diagnosis.

Initially, only 21.4% of the subjects were classified as " at goal blood

pressure, "

but nearly half classified as " not at goal " changed classification to " at

goal " when proper blood pressure techniques were used, the researchers

reported.

Additionally, patients who had no pre-existing hypertension diagnosis but

received a diagnosis based on their measurements that day had their

classifications

changed when appropriate blood pressure techniques were used.

" Eighty-one percent of these patients changed JNC categories, " reported Dr.

Burgess, " either from stage 2 hypertension to stage 1 hypertension, from

stage

1 hypertension to prehypertension or from prehypertension to normal. We did

not have anyone go up in classification. "

Based on this study, the researchers not only concluded that critical

decisions about blood pressure management may be based on inaccurate

readings in

the majority of cases in clinics, but they also determined that following

AHA and JNC-7 recommendations closely " results in significantly lower blood

pressure

measurements, " said Dr. Burgess.

Presentation title: Blood Pressure Rising: Is There a Difference between

Current Clinical and Recommended Measurement Techniques? Abstract RS015