CATIS-2: Delayed Antihypertension Tx for Acute Ischemic Stroke Still an Option

DALLAS -- Antihypertensive treatment could wait for 7 days following an acute ischemic stroke (AIS), so long as the patient has no comorbidities that warrant the emergency reduction of their blood pressure (BP).

In the CATIS-2 trial, there was no significant difference in the composite of major disability and death between patients with AIS who received either early or delayed antihypertensive treatment after 3 months (OR 1.17, 95% CI 0.98-1.40, P=0.092) reported Liping Liu, MD, PhD, of Capital Medical University and the National Clinical Research Center for Neurological Diseases in Beijing.

There also was no significant difference between the time at which antihypertensive treatment was administered (early or delayed) and major vascular events (OR 1.14, 95% CI 0.89-1.46, P=0.3) and recurrent stroke (OR 1.08, 95% CI 0.85-1.38, P=0.53) at 90 days, according to findings from the multicenter, randomized trial.

"Increased blood pressure is really common in the acute stage and is strongly associated with poor neurological functions and the recurrence of ischemic stroke. So we have lots of concerns and problems facing either in clinical practice and clinical research," Liu said in a presentation at the American Stroke Association International Stroke Conference.

Subgroup analysis showed that there were differences observed in systolic BP between the two groups following randomization, with a "moderate reduction" in BP for both.

After the first 24 hours, those who got delayed antihypertensive treatment had an average systolic BP 8.6 mmHg (4.9%), while those who got early antihypertensive treatment had an average systolic BP of 16.4 mmHg (9.7%) for a -7.8 mmHg difference (95% CI -6.7 to -8.9, P<0.0001). After a week, the average systolic BPs were 150.9 mmHg and 139.1 mmHg, respectively, for a -11.9 mmHg difference (95% CI -12.9 to -10.9, P<0.0001).

Results from the first CATIS trial came out in 2014 in JAMA, and showed that among patients with AIS, BP reduction with antihypertensive meds versus no hypertensive meds did not cut the likelihood of death and major disability at 14 days or hospital discharge. Subgroup analysis revealed a reduction in BP levels for patients who had received antihypertensive medications either 24 hours or longer following stoke onset, which was tied to a lowering of risk for major disability or death.

In a 2014 JAMA editorial, Jeffrey L. Saver, MD, of the University of California Los Angeles, stated that "CATIS provides evidence to support the view that how blood pressure is managed in the subacute period from 12 hours to 2 weeks after ischemic stroke does not matter much. When blood pressure remained untreated during the first 2 weeks, the frequency of composite recurrent vascular events (vascular death, nonfatal stroke, nonfatal myocardial infarction, rehospitalization for angina, congestive heart failure, or peripheral arterial disease) was low, approximately 3.0%, affording little opportunity for active blood pressure lowering to improve outcome."

However, Saver warned that "the CATIS trial reflects the population and clinical practice of China and may not be fully generalizable to other populations," while Liu's group noted that the "optimal BP management strategy in these patients remains uncertain and should be the focus of future research."

CATIS-2 trial patients had a mean age of 63.7 and the majority were men with an elevated BP following MRI- or CT-confirmed AIS, with systolic BP between 140 and 200 mmHg and diastolic BP between 80 and 120 mmHg.

Analysis was done with 4,783 patients from June 13, 2018 to Oct. 15, 2022 at 106 sites. Patients were more or less evenly split between the two study arms. Median systolic and diastolic BPs were 162.8 and 91.8 mmHg, respectively. Over three-fourths had hypertension. The median time from stroke onset to intervention was 1.9 days. Those with an NIH Stroke Scale score of ≥21 were excluded; median score in the study population was 3.

Study limitations included the fact that the BP reduction seen within the first 7 days in the early-treatment group was moderate, according to the authors. Also, because patients treated with baseline IV thrombolysis or endovascular thrombectomy were excluded, the results cannot be generalized to those patients, they cautioned.

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