doi: 10.1161/01.CIR.0000067636.58822.73
(Circulation. 2003;107:e9018.)
© 2003 American Heart Association, Inc.
Cardiovascular News
Circulation Newswriter
Beware That Morning Surge
Higher surges in blood pressure recorded in the morning are associated with increased stroke risk, according to a report by Japanese researchers in this week’s issue of Circulation (Circulation. 2003;107:1401–1405). The scientists, led by Kazuomi Kario, MD, of the Department of Cardiology at Jichi Medical School in Tochigi, Japan, said the finding in their prospective study could provide new targets for therapy that prevent target organ damage and subsequent cardiovascular events in patients with hypertension.
In this study, scientists studied stroke prognosis in 519 older patients with hypertension in whom ambulatory blood pressure monitoring was formed and silent cerebral infarct was assessed by magnetic resonance imaging of the brain. The morning surge in blood pressure was calculated by subtracting mean systolic blood pressure during 1 hour that included the lowest sleeping blood pressure from the mean systolic blood pressure during the 2 hours after waking. Cardiovascular events most often occur during the morning hours, which led the researchers to study the blood pressure during this period.
Over an average of 51 months, the patients suffered 44 strokes. They were divided into groups on the basis of the calculation of their morning blood pressure surge. Those in the top decile had a higher baseline prevalence of multiple infarcts (57% versus 33%) and a higher incidence of stokes (19% versus 7.3%) during the follow-up period, when compared with the other group. The effect of the morning surge in blood pressure was independently associated with stroke without effect by the ambulatory or nocturnal blood pressure, falls, or silent infarct.
In an accompanying editorial, Norman M. Kaplan, MD, of The University of Texas Southwestern Medical Center at Dallas, noted, "Some days it just doesn’t pay to get out of bed." He attributed the surge to sudden activation of the sympathetic nervous system. "Whereas arousal from sleep is associated with a slight rise in plasma epinephrine, arising induces a significant rise both in epinephrine and norepinephrine."
He noted that discovery of this morning surge requires ambulatory monitoring of blood pressure, but it is not reimbursed by most third-party payers, although it is used more routinely in other countries. He recommends that patients measure their blood pressures in the early morning, soon after they awake.
"In the study by Kario et al, the danger of an early morning surge was lessened among those who remained on one or another antihypertensive medication during the 4-year follow-up," Dr Kaplan noted.
He said that patients with morning blood pressure surges should be recognized as being at risk of stroke or cardiovascular events, He said that if the morning surges are above 140/90 mm Hg, additional antihypertensive therapy should be used, particularly those that provide control for 24 hours or longer.
"Even if such formulations are used, early morning home blood pressure measurements should be checked to ensure maximal cardiovascular protection," he recommended.
Obesity Suspected Culprit in Childhood High Blood Pressure
An unexpected increase in the numbers of children with high blood pressure may result from the growing epidemic of childhood obesity, according to researchers at the American Heart Association’s recent 43rd Annual Conference on Cardiovascular Disease Epidemiology and Prevention in Miami, Fla.
"Children and adolescents from this survey showed increases in systolic blood pressure compared to what we would have expected based on previous studies of North American youth," says lead investigator Gilles Paradis, MD, Associate Professor at McGill University School of Medicine in Montreal, Canada. "Our results suggest that this increase in systolic pressure is related to the obesity epidemic in children and adolescents."
In 1999, Dr Paradis and his fellow researchers surveyed 4500 Quebec youngsters aged 9, 13, and 16 years. They gathered lifestyle and socio-demographic variables through age-appropriate questionnaires administered to the youths. They also measured height, weight, blood pressure, and body fat. Blood pressures were recorded for 3589 of the youngsters in the study.
Overall, systolic blood pressures recorded were elevated above what was suspected and were higher for 13- and 16-year-olds as well as for boys in the study. The average blood pressures were 103/57 mm Hg for those aged 9 years, 112/59 mm Hg for those aged 13 years, and 119/62 mm Hg for those aged 16 years. Elevated systolic pressures adjusted for height were found in 4.4% of the 9-year-olds, 16.7% of the 13-year-olds, and 19.7% of the 16-year-olds.
Blood pressures rose with increasing body mass index. Dr Paradis said that if the results are confirmed by other investigators, "These children will be tomorrow’s hypertensive adults. If these levels of blood pressure persist, the number of people with hypertension could increase substantially over the next decade."
Everyone Suffers in Communities With High Rates of Uninsured People
In communities where the rates of people without health insurance are high, officials are more likely to reduce the availability of hospital services, divert public funds away from preventing disease and promoting health, as well as watching for outbreaks of new infectious ailments. Tax dollars must be reallocated to pay for people who cannot afford their own medical care, according to a new report from the Institute of Medicine.
The report, A Shared Destiny: Community Effects of Uninsurance (http://www.nap.edu/books/0309087260/html/), notes that large numbers of uninsured people in a community can reduce access to emergency care, specialty services, and hospital care across a community—even for those people who have health insurance coverage. For example, across the United States, overcrowding in the nation’s emergency rooms is making it more difficult for people to receive the care they need.
"It is misguided and even dangerous to assume that lack of health insurance harms only those who are uninsured," said Arthur Kellermann, co-chair of the committee that wrote the report, and Professor and Chair of Emergency Medicine at Emory University School of Medicine, Atlanta, Ga. "The rest of the community pays for uncompensated medical care either directly or indirectly, and high rates of uninsurance can strain community health systems to the point that important services have to be cut or eliminated."
The Institute of Medicine report predicts that the rates of people without insurance in the United States will increase as unemployment escalates along with health care costs and federal and state budget deficits. The report and its author note that lack of reimbursement for care to the uninsured has curtailed the availability of services, such as those given to trauma victims and to people with HIV.
Across the nation, cities have closed their public facilities or converted them into for-profit entities because of the burden of uncompensated care. In Los Angeles County, officials closed 11 of 18 public health clinics and one of six public hospitals last year along with 5000 jobs in the health care sector. Hospitals are no longer able to shift the costs of uncompensated care to insured patients because of cost-cutting programs from the nation’s insurers over the past two decades.
According to the March 2002 Current Population Survey by the Census Bureau, 16.5% of the population under the age of 65 are without health coverage. Iowa has the lowest rate at 8.7% with Texas having the highest rate at 26%.
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