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Dangerously high blood pressure spikes more prevalent in black adults
Black American adults experience a hypertensive crisis at a
rate that is five times the national average, according to a
study presented at the American Heart Association’s Joint
Hypertension 2018 scientific sessions, an annual conference
focused on recent advances in hypertension research.
Hypertensive crisis is a complication of high blood
pressure in which blood pressure quickly and severely soars to
life-threatening levels. People often can avoid this dangerous
blood pressure escalation by keeping their blood pressure
under control with medications and lifestyle modifications.
‘We studied an inner-city population to find that being
black is a risk factor for progressing from hypertension
to hypertensive crisis,’ said study author Dr Frederick A
Waldron, an emergency medicine physician at Newark Beth
Israel Medical Centre, New Jersey. ‘Now that we have effective
anti-hypertensive medications available, hypertensive crisis
and hypertensive emergency, a rare but further progression of
hypertensive crisis in which organ damage occurs, should not
exist to this degree among black or other patients.’
In what Waldron said is the largest case–control study to
date on hypertensive-crisis patients, researchers looked back
at emergency department medical records of more than 15
000 patients from 2013 to 2016. They defined hypertensive
crisis as blood pressure at or above 200/120 mmHg.
They found: nearly 1 800, or 11.4% of the 15 631
hypertensive patients that came through the emergency
department in the three-year study were in hypertensive
crisis; nearly 90% of those in hypertensive crisis were black;
one in four, or 25%, of patients with hypertensive crisis
went on to develop catastrophic organ failure, including
stroke, congestive heart failure, kidney failure or heart
attack. Being older than 65 years or male, as well as having
anaemia, chronic kidney disease or a history of stroke and
cardiovascular diseases, including high cholesterol levels,
predicted higher risk for hypertensive emergencies. Anaemia
has not been identified before as a hypertensive emergency
risk factor, according to Waldron. Insurance status and
access to primary care did not affect patients’ odds of having
a hypertensive crisis.
‘There is no good treatment for organ damage, so the
best way to address this is to develop a preventative strategy,’
Waldron said. He suggests efforts to help patients take their
medicine properly could help reduce hypertensive crises.
The numbers in the study may be underestimated due to
differing definitions of hypertensive crisis. For example, the
American Heart Association defines it as blood pressures at
or above 180/120 mmHg. This study defined hypertensive
crisis as above 200/120 mmHg.
Waldron said future studies should determine rate of
adherence to blood pressure medications, and follow patients
in hypertensive crisis longer to determine true incidence of
hypertension emergency.
Source: Medical Brief 2018