Caution needed on aggressive BP lowering
Elderly patients on treatment for hypertension were five times more likely to have injurious falls or syncope in a new study, TILDA*, than those in the SPRINT** study, suggesting a need for caution in aggressive lowering of blood pressure (BP) among certain patients in contrast to recommendations from SPRINT.
Previous findings from SPRINT demonstrated that intensive treatment of elderly adults (aged ≥75 years, mean age 79.9 years) to a systolic BP target of <120 mm Hg significantly reduced the rates of cardiovascular events and death without significantly increasing the rates of injurious falls or syncope ─ the common side effects of low BP ─ compared with those treated to a target of <140 mm Hg (standard care). [JAMA 2016;315:2673-2682]
“However, prior to the adoption of an intensive strategy to lower systolic BP in the oldest segment of the population, it is prudent to determine if individuals meeting inclusion criteria for SPRINT outside the clinical trial context are similar to trial participants, especially with regard to risk for adverse outcomes,” according to researchers of the TILDA study.
“We need to be cognizant of the fact that the [SPRINT] trial was not powered for adverse events such as falls causing injury,” reminded TILDA lead author Dr Donal Sexton of Trinity College Dublin in Dublin, Ireland.
In TILDA, 407 community-dwelling individuals (mean age 80.1 years) in Ireland who met the inclusion criteria for SPRINT were followed up on falls and syncope by self- or proxy-report. [JAMA Intern Med 2017;doi:10.1001/jamainternmed.2017.2924]
After a mean follow-up of 3.4 years (similar to the median 3.4 years in SPRINT), 27.3 percent of TILDA participants reported an injurious fall and 13.3 percent reported syncope while receiving standard care in the community. This is in contrast to the injurious falls reported in 5.5 percent and syncope in 2.4 percent of the participants undergoing standard care in SPRINT, equivalent to about a fivefold difference to TILDA findings.
“Physicians ought not to expect a similarly low rate of adverse events in clinical practice as was observed in the trial when lowering blood pressure in older people,” said Sexton.
“Given the high baseline rates of falls and syncope, any increase in these rates due to intensive treatment of hypertension could result in harm,” added Sexton and co-authors. “[T]he risks and benefits of lowering blood pressure should be individualized for each patient.”
The researchers also noted several differences in patient characteristics between the two studies. For instance, all TILDA participants were Caucasians as opposed to 74.8 percent of participants in SPRINT. At baseline, orthostatic hypotension was more prevalent among subjects of TILDA than SPRINT (12.3 percent vs 9.4 percent). Also, there were more patients in SPRINT with a history of cardiovascular disease (23.4 percent vs 17.7 percent), statin use (52.8 percent vs 39.1 percent), and aspirin use (58.0 percent vs 39.3 percent), which according to the authors, reflect a higher cardiovascular risk profile.
“[L]ow blood pressure and particularly drops in standing blood pressure are linked not only to falls, fractures and fall- and blackout-related injuries, but also to depression and possibly other brain health disorders,” said TILDA principal investigator Professor Rose-Anne Kenny of Trinity College Dublin.
“[W]e advise caution in applying the SPRINT recommendations to everyone over 75 years without detailed assessment of an individual’s risk versus possible benefit until such a time as we can provide more clarity regarding treatment.”