Bottom Line: Hypertension in middle age (48 to 67 years) was associated with a greater, although still a modest, decline in cognition over a 20-year period compared with individuals who had normal blood pressure.
Author: Rebecca F. Gottesman, M.D., Ph.D., of the Johns Hopkins University School of Medicine, Baltimore, and colleagues.
Background: Evidence suggests hypertension is a risk factor for cognitive change and dementia and midlife hypertension may be the stronger risk factor.
How the Study Was Conducted: Authors used the Atherosclerosis Risk in Communities (ARIC) study to examine the effects of hypertension by analyzing the results of three cognitive tests over time. Data from 13,476 participants (3,229 of whom were African American) were used and the maximum follow up was 23.5 years.
Results: The decline in global cognitive scores for participants with hypertension was 6.5 percent greater than for individuals with normal blood pressure. An average ARIC participant with normal blood pressure at baseline had a decline of 0.840 global cognitive z score points during the 20-year period compared with 0.880 points for participants with prehypertension and 0.896 points for patients with hypertension. Individuals with high blood pressure who used medication had less cognitive decline during the 20 period than participants with high blood pressure who were untreated. A greater decline in global cognition scores also was associated with higher midlife blood pressure in white participants than in African Americans.
Discussion: "Although we note a relatively modest additional [cognitive] decline associated with hypertension, lower cognitive performance increases the risk for future dementia, and a shift in the distribution of cognitive scores, even to this degree, is enough to increase the public health burden of hypertension and prehypertension significantly. Initiating treatment in late life might be too late to prevent this important shift. Epidemiological data, including our own study, support midlife BP [blood pressure] as a more important predictor of – and possibly target for prevention of – late-life cognitive function than is later-life BP."
(JAMA Neurol. Published online August 4, 2014. doi:10.1001/.jamaneurol.2014.1646. Available pre-embargo to the media at http://media.jamanetwork.com.)
Editor's Note: An author made a conflict of interest disclosure. Numerous funding disclosures also were made. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
Editorial: Blood Pressure, Prevention of Cognitive Impairment
In a related editorial, Philip B. Gorelick, M.D., M.P.H., of the Michigan State University College of Human Medicine, Grand Rapids, writes: "In this issue of JAMA Neurology, Gottesman and colleagues provide additional evidence to support the association between midlife hypertension and cognitive change. The study provides a unique opportunity to understand the role of raised BP on cognition during a 20-year period."
(JAMA Neurol. Published online August 4, 2014. doi:10.1001/.jamaneurol.2014.2014. Available pre-embargo to the media at http://media.jamanetwork.com.)
Editor's Note: Dr. Gorelick has been a consultant to Novartis in the development of a clinical trial protocol of a novel antihypertensive medication for preservation of cognition. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
Media Advisory: To contact author Rebecca F. Gottesman, M.D., Ph.D., call Audrey Huang at 410-614-5105 or email audrey@jhmi.edu. To contact editorial author Philip B. Gorelick, M.D., M.P.H., call Jason Cody at 517- 432-0924 or email jason.cody@cabs.msu.edu.
To place an electronic embedded link to this study in your story Links for this study and editorial will be live at the embargo time: http://archneur.jamanetwork.com/article.aspx?doi=10.1001/jamaneurol.2014.1646 and http://archinte.jamanetwork.com/article.aspx?doi=10.1001/jamainternmed.2014.2014.
Journal
JAMA Neurology