Hypertension Is Related to Cognitive Impairment

Abstract

Abstract-Recent findings of a linkage between high blood pressure (BP) and later development of dementia have given new prospects on cerebral target-organ damage in hypertension and have added substance to the concept of "preventable senility." The aim of this study was to analyze the impact of hypertension, circadian BP profile, and disturbed glucose metabolism on cognitive function. The study population consisted of 999 seventy-year-old men from a population-based cohort study in Uppsala, Sweden, followed with respect to cardiovascular risk factors since the age of 50 years. At the age of 70, 24-hour ambulatory BP was monitored together with measurements of insulin sensitivity, glucose tolerance, serum lipids, and lipoproteins. Cognitive function was assessed by the Mini-Mental State Examination and the Trail-Making Test.High diastolic BP at baseline predicted later impaired cognitive performance, even after excluding men with a previous stroke (nϭ70). Cross-sectional measurements at age 70 showed that high 24-hour BP, nondipping, insulin resistance, and diabetes all were related to low cognitive function. The relationships between hypertension and cognitive impairment were strongest in untreated men. These data from a general population of healthy elderly men indicate that hypertension and associated metabolic disturbances might be susceptibility factors for cognitive disorders. The findings add support to possibilities of intervention in early stages in cognitive decline, ie, before manifest dementia. (Hypertension. 1998;31:780-786.)Key Words: cognition Ⅲ blood pressure monitoring, ambulatory Ⅲ diabetes Ⅲ insulin resistance T he question of whether some degree of cognitive deterioration is an inevitable part of aging or should be considered as a pathological prestage of dementia is currently debated. This is a field in need of research 1 because further decline in cognition might be preventable in the early stages of "cognitive impairment nondementia." Vascular dementia is a common form of dementia; in the oldest elderly patients it is as frequent as Alzheimer's disease.2 Recently, a 15-year follow-up study showed that high BP predicted dementia in the oldest elderly patients, irrespective of subtype.3 Little is known about how cognitive function is affected by vascular risk factors in the general population. The aim of the present study was to analyze the associations between BP, diurnal BP variation, disturbances in glucose and lipid metabolism, and cognition. We examined cognitive functions in a population-based cohort of 70-year-old men in which longitudinal measurements of vascular risk factors were available. MethodsThe study population consisted of 999 men. They were participants in a health survey focusing on cardiovascular risk factors that was started in the beginning of the 1970s in Uppsala, Sweden. The original cohort was defined as all men born in 1920 to 1924, who resided in the municipality of Uppsala in 1970Uppsala in to 1973. A total of 2322 (81.7%) men participated in the baseline examina...

Long‐Term Blood Pressure Level and Variability From Midlife to Later Life and Subsequent Cognitive Change: The ARIC Neurocognitive Study

“…Higher midlife SBP levels have been consistently associated with lower cognitive function in later life 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11. Most studies have assessed cognitive function at a single time point,4, 5, 6, 7, 8, 9 and, thus, our results have extended our understanding of this relationship by taking cognitive decline into account.…”

“…Most studies have assessed cognitive function at a single time point,4, 5, 6, 7, 8, 9 and, thus, our results have extended our understanding of this relationship by taking cognitive decline into account. In contrast, prior findings on the relationships between midlife DBP levels and late‐life cognitive function have been inconsistent 5, 6, 8, 30. In a cohort of Swedish men (n=999), DBP ≥70 mm Hg (versus DBP <70 mm Hg) at the age of 50 years was associated with lower cognitive function at the age of 70 years 6.…”

“…In contrast, prior findings on the relationships between midlife DBP levels and late‐life cognitive function have been inconsistent 5, 6, 8, 30. In a cohort of Swedish men (n=999), DBP ≥70 mm Hg (versus DBP <70 mm Hg) at the age of 50 years was associated with lower cognitive function at the age of 70 years 6. In a Finnish cohort (n=1449; 62% women), no relationship was observed between DBP (≥90 versus <90 mm Hg) at ≈50 years of age and the presence of cognitive dysfunction 21 years later 5.…”

“…Consequently, PP (SBP minus DBP) increases steeply after middle age. Therefore, characterization of individual DBP in midlife by a single measurement may be limited, and this might have contributed to the inconsistent results 5, 6, 8, 30. Indeed, a prior study from the ARIC Study demonstrated that higher DBP at visit 2 was associated with a steeper decline in global cognition from visit 2 to visit 5 11.…”

“…Evidence supporting a link between midlife blood pressure (BP) levels and late‐life cognitive outcomes continues to accumulate 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12. In addition to BP levels, BP variability may be associated with cognitive function 12, 13, 14, 15, 16, 17, 18.…”