麻豆传媒

NASHVILLE, Tenn. -- Aggressively lowering blood pressure in patients with acute stroke was successful in getting pressure to lower levels, but the treatment was no more successful in overall outcomes compared with patients whose anti-hypertensive medicines were stopped at admission, researchers suggested here.

In a clinical trial conducted in China, researchers found that, after 3 months, patients who were treated to lower blood pressure had a death or major disability rate of 23.1% compared with a rate of 21% among the control population (P=0.13), said , chair of epidemiology at Tulane University.

There were no statistical differences in recurrent stroke, vascular events, or modified Rankin Score (mean 1.0 for both groups) at 3 months, he said in his oral presentation at the American Heart Association's International Stroke Conference.

However, the mean lag between symptom onset and treatment was about 15 hours, raising questions about the applicability to patients treated more quickly.

"Although elevated blood pressure is very common in patients with acute ischemic stroke, the management of hypertension among them remains controversial," he said, and hence researchers organized the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS).

In the multicenter, randomized clinical trial, researchers enrolled 4,071 patients who were at least 22 years old and were diagnosed with ischemic stroke, confirmed by brain CT or MRI within 48 hours of symptom onset. To be eligible for the trial patients had to have had a systolic blood pressure in the 140 to 220 mm Hg range at baseline. Patients were recruited from 26 hospitals across China from August 2009 to May 2013.

The antihypertensive treatment goal was to lower systolic blood pressure by 10% to 25% within the first 24 hours after randomization to achieve a systolic blood pressure of less than 140 mm Hg and a diastolic blood pressure of less than 90 mm Hg within 7 days, and to maintain this level of blood pressure control during the remainder of a patient's hospitalization. The intervention in the control patients was to stop all regular antihypertensive medications.

In the analysis presented during the late-breaker plenary session, He reported on outcomes of 1,965 patients who were randomized to antihypertensive treatment and 1,948 patients in the control group. The other patients were lost to follow-up, he said.

The intervention was successful in lowering blood pressure, the researchers reported. Within 72 hours, systolic blood pressure in the group receiving treatment had fallen from a baseline mean of about 165 mm Hg to about 140 mm Hg. Blood pressure in controls also fell, but not to the extent of the patients receiving treatment – from 165 mm Hg to about 155 m Hg.

After 2 weeks the treated population had an average systolic blood pressure below 140 mm Hg compared with the untreated patients whose systolic blood pressure was about 155 mm Hg after 2 weeks.

Even after 1 year, the patients who were put on treatment at the hospital still had systolic blood pressure below 140 mm Hg – an average of 138.8 mm Hg – compared with an average of 140.2 mm Hg among the controls. That 1.4 mm Hg was statistically significant (P<0.001), He said.

But even though systolic blood pressure was lowered, the outcomes were not different, he said. All-cause mortality was statistically the same (P=0.35), as were recurrent stroke (P=0.80), vascular events (P=0.76); and a composite of death or vascular events (P=0.51).

The patients in the trial were about 62 years old on average; about 64% of the participants were men. They began treatment about 15 hours after the onset of stroke symptoms. About half the patients were on some form of antihypertensive medication; about 80% were classified as having high blood pressure.

"Among patients with acute stroke, blood pressure reduction with hypertensive medications during hospitalization did not reduce the composite outcome of death and major disability or vascular events in one year," He said.

"This is another highly debated topics among neurologists," professor of neurology and neurological surgery at the University of Washington, Seattle, and program chair of the ISC meeting, told 麻豆传媒. "It is a common practice that when someone comes in with an acute stroke you take away antihypertensives because you want blood pressure to be higher in order to improve perfusion – but there really is no data to support that.

"There have been a couple of studies with immediate blood pressure lowering that have either shown – like this study – no benefit or actually even harm," Becker said. "If you look at the outcomes of Dr. He's study at one year there was a P-value of 0.1 – in the wrong direction. This study suggests again that we don't have any data to tell people that they should be lowering blood pressure aggressively in acute stroke.

"I think the caveat is that if you are someone who is going to get tissue plasminogen activator and endovascular therapy, there are different guidelines to adhere to," she said.

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