Latent Adverse Effects of High Blood Pressure

High blood pressure (hypertension) in middle age plays a critical role in whether blood pressure later in life may affect memory and thinking. Lenore J. Launer, from the National Institute on Aging (Maryland, USA), and colleagues enrolled 4,057 older men and women, absent of dementia, who had their blood pressure measured in middle-age (average age 50 years). In late life (average age 76 years) their blood pressure was remeasured; participants underwent MRIs that assessed the small vessels in the brain., and were assessed for memory and thinking ability. The team found that the association of blood pressure in old age to brain measures depended on a history of blood pressure in middle age. Higher systolic and diastolic blood pressure were associated with increased risk of brain lesions and tiny brain bleeds. This was most noticeable in people without a history of high blood pressure in middle age. In subjects with a history of high blood pressure in middle age, lower diastolic blood pressure in older age was associated with smaller total brain and gray matter volumes. This finding was reflected in memory and thinking performance measures as well. In people with high blood pressure in middle age, lower diastolic blood pressure was associated with 10% lower memory scores. Writing that: “late-life [blood pressure] differentially affects brain pathology and cognitive performance, depending on the history of midlife hypertension,” the study authors submit that: “Our study suggests history of hypertension is critical to understand how late-life [blood pressure] affects brain structure and function.”