Immediate antihypertensive therapy post-stroke reduces recurrence in patients with hypertension history
Immediate antihypertensive treatment following an acute ischaemic stroke in patients with a history of hypertension may reduce their risk of recurrent stroke, a subgroup analysis of the CATIS* trial showed.
“[E]arly antihypertensive therapy was associated with lower rates of 3-month recurrent stroke among patients with history of hypertension,” said the researchers. “This … analysis provides data to support early antihypertensive intervention among patients with ischaemic stroke and a history of hypertension, and early treatment could help them transition to long-term antihypertensive therapy for secondary prevention.”
“[F]or patients without prior hypertension, the decision to decrease blood pressure (BP) with antihypertensive treatment should be based on individual clinical judgment and requires more caution,” they added.
Study participants were 4,071 patients who had experienced an acute ischaemic stroke (mean age 62 years, 64 percent male, 77.9 percent with thrombotic stroke) and had increased systolic BP (SBP) levels (140–220 mmHg). They were randomized to either receive immediate antihypertensive treatment (n=2,038) or have all antihypertensive medications discontinued during hospitalization (control group; n=2,033) following the stroke. The aim of antihypertensive therapy was to establish a 10–25 percent reduction in SBP within 24 hours and a BP of ≤140/<90 mm Hg within 7 days to be maintained throughout hospitalization. All patients were prescribed antihypertensives following hospital discharge.
Almost 79 percent of patients (n=3,209) had a history of hypertension, of whom 1,610 and 1,599 were assigned to the treatment and control groups, respectively. Of the 862 patients without a history of hypertension, 428 and 435 were assigned to the treatment and control groups, respectively.
Compared with the control group, the composite incidence of death and major disability** at 14 days or upon hospital discharge did not significantly differ between patients with or without a history of hypertension who received treatment (odds ratio [OR], 1.00, 95 percent confidence interval [CI], 0.87–1.16 [hypertension] and OR, 1.00, 95 percent CI, 0.75–1.32 [without hypertension]; phomogeneity=0.97). [JAMA Network Open 2019;2:e198103]
However, immediate antihypertensive treatment reduced the risk of stroke recurrence at 3 months among patients with a history of hypertension (OR, 0.44, 95 percent CI, 0.25–0.77; p=0.004), with no impact among patients without a history of hypertension (OR, 3.43, 95 percent CI, 0.94–12.55; p=0.06; phomogeneity=0.005).
The risk of vascular events*** also reduced among patients with a history of hypertension who received immediate antihypertensive treatment (OR, 0.66, 95 percent CI, 0.43–1.02; p=0.06), with little impact among those without hypertension history (OR, 1.91, 95 percent CI, 0.75–4.83; p=0.17; phomogeneity=0.04).
The difference in SBP between patients in the treatment and control groups was a mean -9.3 mmHg and -5.8 mmHg in those with and without a history of hypertension, respectively (p<0.001 for both), at 14 days, and -3.1 mmHg (p<0.001) and -2.4 mmHg (p=0.005), respectively, at 3 months. Significant differences in diastolic BP (DBP) were also seen with antihypertensive treatment compared with the control group at 3 months, with mean differences of -1.3 mmHg (p<0.001) and -1.9 mmHg (p=0.001) in patients with and without a history of hypertension, respectively.
There is ongoing discussion as to whether BP management strategies following ischaemic stroke should differ based on pre-stroke hypertension history, said the researchers.
“[While] BP-decreasing treatment may reduce vascular damage, cerebral oedema, and haemorrhagic transformation of the cerebral infarction, … and hasten the transition to long-term antihypertensive therapy, … early BP reduction may also decrease cerebral perfusion of the ischaemic tissue and further increase the size of the cerebral infarction,” they said, pointing out that the latter is of particular concern in patients with hypoperfusion or those without hypertension.
“The present subgroup analysis confirmed the neutral effects of early antihypertensive treatment [following ischaemic stroke] on death or major disability regardless of history of hypertension,” they said. Furthermore, this study enabled the assessment of the impact of hypertension history on the association between immediate post-stroke BP reduction and subsequent outcomes specifically in the context of ischaemic stroke.