3-year intensive BP lowering in older hypertensives: No clear benefit on mobility outcomes

In older adults with systolic hypertension, targeting a 24-hour ambulatory systolic blood pressure (BP) of ≤130 vs ≤145 mm Hg does not appear to be beneficial in terms of mobility outcomes during a 3-year period, although it yields a favourable effect on subcortical white matter disease, according to data from the INFINITY trial.

“These data suggest that 3 years was likely too short a duration for reductions in accrual of white matter hyperintensity to translate to functional benefit,” the authors noted.

INFINITY involved 199 elderly patients (mean age, 80.5 years; 54 percent female) with systolic hypertension (average 24-hour systolic BP, 149 mm Hg) and magnetic resonance imaging evidence of white matter hyperintensity lesions. These patients were randomized to treatment groups targeting a 24-hour mean systolic BP of ≤130 mm Hg (intensive group) or ≤145 mm Hg (standard) with antihypertensive therapies.

Goal BPs were achieved after a median treatment period of 3–4 months, with a median 24-hour systolic BP of 127.7 mm Hg in the intensive treatment group and 144.0 mm Hg in the standard treatment group (average difference, 16.3 mm Hg).

Three-year intensive BP lowering did not produce a significant change in mobility (gait speed) compared with standard treatment (0.40 vs 0.42 s, respectively; p=0.91). However, intensive treatment was associated with less accrual of white matter hyperintensity lesions (0.29 percent vs 0.48 percent; p=0.03). [Circulation 2019;doi:10.1161/CIRCULATIONAHA.119.041603]

Cognitive outcomes were likewise similar in the two treatment groups. Major adverse cardiovascular events occurred with greater frequency in the standard treatment group (17 vs 4 patients; p=0.01). There was no significant between-group difference in the occurrence of falls, with or without injury, and syncope.

“Results of the trial demonstrated a significant impact of lower 24-hour systolic BP on progression of white matter lesions, but it was unaccompanied by a detectable impact on mobility and cognitive function,” the authors said, adding that these data are consistent with findings from a substudy of 192 patients with a history of stroke from the PROGRESS trial (Perindopril Protection Against Recurrent Stroke). [Circulation 2005;112:1644-1650]

They explained that the inability to demonstrate effects on the functional parameters may be attributed to a shorter-term follow-up, given that the accrual of white matter hyperintensity volume occurs silently for many years. “[This is] compounded by the requirement that patients entering INFINITY had intact mobility, thus requiring >3 years to show functional deterioration.”

Nevertheless, a 24-hour average systolic BP ≤130 mm Hg is a reasonable treatment goal, given that intensive treatment of ambulatory BP in older people was well tolerated and accompanied by lower numbers of cardiovascular events, the authors added.

*INtensive versus standard ambulatory blood pressure lowering to prevent functional DeclINe in the ElderlY