Antihypertensive Medications, History of Hypertension Linked to Cognitive Decline and Brain Atrophy
By Brian Hoyle
Washington, DC -- July 22, 2015 -- The use of antihypertension medication has been associated with cognitive decline and brain atrophy, according to results of a cross-sectional study presented here at the 2015 Alzheimer’s Association International Conference (AAIC).
Medication use per se may not be the culprit, however;. rather, a history of hypertension, which has been linked with dementia and can be destructive to brain structure and function, may play a role.
“In this study, antihypertensive medication use was detrimental to cognition and brain atrophy measures,” explained Shannon L. Risacher, PhD, Indiana University School of Medicine, Indianapolis, Indiana, on July 19.
Dr. Risacher cautioned against interpreting these results as a causal association, suggesting that the culprit is likely a history of hypertension, with its attendant progressive and longer-term damage to brain structure. This view argues for better control of hypertension earlier in life as a way of lessening the risks of cognitive decline.
“It is important for antihypertensive treatments to effectively control hypertension and normalise blood pressure, as [patients] with uncontrolled hypertension show the most cognitive decline and brain abnormalities,” Dr. Risacher noted. “Treatment of hypertension with antihypertensive medications may be protective.”
Dr. Risacher and colleagues used data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) to investigate the effect of high blood pressure (systolic pressure ≥140 mm Hg and diastolic pressure ≥90 mm Hg) and antihypertensive medications on cognition, white matter hyperintensity, and brain atrophy. Antihypertensive medications included diuretics, beta blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, alpha blockers, alpha-2 receptor agonists, alpha-beta blockers, and vasodilators.
The team assessed cognition with an executive-function composite score and Trail Making test. They used T1-weighted magnetic resonance imaging to determine cortical and subcortical volumes, and lobar cortical thickness.
The 1,313 adult participants included 297 with normal cognition, 102 older adults with serious memory problems, 306 with mild cognitive impairment (MCI), 358 with late MCI, and 250 with mild Alzheimer’s disease. The subjects were stratified into 4 groups: no hypertension and no treatment, hypertension and no treatment, controlled hypertension, and uncontrolled hypertension.
Executive function was found to be poorer in older adults on antihypertensive medications, who had a history of hypertension. In particular, patients with uncontrolled hypertension showed the poorest performance, especially those on antihypertensive medications and those with MCI.
White matter hyperintensity was increased in older adults with hypertension and patients on antihypertensive medications, especially those with uncontrolled hypertension. Cortical and temporal lobe atrophy was observed in patients receiving antihypertensive medications, especially those with uncontrolled hypertension.
Future plans include teasing out the effects of the various antihypertensive medications, clarifying the nature of the long-term cognitive and structural effects of high blood pressure and antihypertensive medications, determining the influences of high blood pressure and blood-pressure medications on blood flow, and identifying genetic determinants.
Funding for this study was provided by the National Institutes of Health, Bethesda, Maryland; the Alzheimer’s Association, Raynham, Massachusetts; and the Alzheimer’s Drug Discovery Foundation, New York, New York.
[Presentation title: Effect of Hypertension and Antihypertensive Medication on Executive Function, Brain Atrophy, and White Matter Hyperintensities. Abstract 4876]