Now, keep up to date
with daily feeds of newly posted stories
about America's Seniors...click on the box
to the left
High Blood
Pressure in the Doctor’s Office may not
predict Heart Risks
Newswise — Continuously measuring blood
pressure may help predict heart disease and
related deaths among individuals with
treatment-resistant hypertension, while
blood pressure readings taken in a medical
office do not appear to predict future heart
risks, according to a report in November 24
issue of Archives of Internal Medicine, one
of the JAMA/Archives journals.
About 10 percent to 30 percent of
individuals with high blood pressure have a
condition known as resistant hypertension,
according to background information in the
article.
For these patients, blood pressure remains
high despite treatment with at least three
antihypertensive drugs, always including a
diuretic (medication that increases urine
output).
Ambulatory blood pressure monitoring, or
measuring blood pressure at regular
intervals throughout the day, is
increasingly important in managing patients
with this condition because of the
possibility of a white-coat effect (when an
individual only has high blood pressure at
the physician’s office).
Gil F. Salles, M.D., Ph.D., studied 556
patients with resistant hypertension who
attended an outpatient clinic between 1999
and 2004.
Participants
underwent a clinical examination and had
their blood pressure monitored continuously
during a 24-hour period (every 15 minutes
throughout the day and every 30 minutes at
night).
They
were followed up at least three to four
times a year until December 2007.
After a median (midpoint) follow-up period
of 4.8 years, 109 (19.6 percent) of
participants had a cardiovascular event or
died of cardiovascular disease.
This included 44 strokes, 21 heart attacks,
10 new cases of heart failure and five
sudden deaths. Seventy patients (12.6
percent) died, including 46 (8.3 percent) of
cardiovascular causes.
Blood pressure measured in the office did
not predict any of these events, whereas
higher average ambulatory blood pressures
(both systolic or top-number and diastolic
or bottom-number) were associated with the
occurrence of fatal and non-fatal heart
events.
This association remained after controlling
for office blood pressure and other risk
factors for heart disease.
When considered separately, nighttime blood
pressure was superior to daytime blood
pressure in predicting heart events.
If nighttime systolic blood pressure
increased by 22 millimeters of mercury, risk
for future heart events increased by 38
percent, whereas an increase of 14
millimeters of mercury in diastolic blood
pressure increased heart risks by 36
percent.
“This study has important clinical
implications,” the authors write.
“First, it reinforces the importance of
ambulatory blood pressure monitoring
performance in resistant hypertensive
patients.
"Furthermore,
ambulatory blood pressure monitoring should
be performed during the whole 24 hours, with
separate analyses of the daytime and
nighttime periods, because it seems that
nighttime blood pressures are better
cardiovascular risk factors than are daytime
blood pressures.”
“Second, it raises the question of whether
therapeutic interventions directed
specifically at controlling nighttime
hypertension will be able to improve
cardiovascular prognosis compared with the
traditional approach of controlling daytime
blood pressure levels,” they conclude.
“This important clinical question should be
addressed in future prospective
interventional studies.”
...
...
...