Nonlinear Relations of Blood Pressure to Cognitive Function

Abstract

Abstract-This investigation examined cross-sectional and longitudinal relations, both linear and nonlinear, of blood pressure (BP) and its interaction with demographic and lifestyle variables to a broad spectrum of cognitive functions. Eight hundred forty-seven participants (503 men and 344 women) from the Baltimore Longitudinal Study of Aging completed tests of verbal and nonverbal memory, attention, perceptuo-motor speed, executive functions, and confrontation naming, and clinical assessment of BP on 1 to 7 occasions over 11 years. Key Words: blood pressure Ⅲ hypertension Ⅲ cognitive function Ⅲ neuropsychology H ypertension is a major risk factor for stroke, vascular dementia, and possibly Alzheimer's disease. 1,2 Even among stroke-free and dementia-free persons, hypertension or higher blood pressure (BP) levels have been related to lowered levels of cognitive function in numerous cross-sectional and longitudinal investigations. 3-5 However, not only high BP but also low BP levels have negative effects on cognitive function. Low BP has been related to risk for Alzheimer's disease and diminished cognitive function. 6 Furthermore, U-shaped relations between BP and cognitive function have been noted such that individuals with high or low BP perform more poorly on cognitive tests and/or display more pronounced cognitive decline than persons with mid-range BP. 7-9 With one exception, 5 these studies are limited by the assessment of BP, cognitive function, or both on a single occasion.The purpose of the present investigation was to examine both cross-sectional and longitudinal relations of concurrently measured BP and cognitive function across 1 to 7 testing sessions in a single stroke and dementia-free sample while evaluating potential nonlinear associations, effect modifiers, and a broad spectrum of cognitive functions. To our knowledge, only 1 previous investigation has assessed concurrently measured BP and cognitive function on Ͼ2 testing occasions in a small sample (nϭ140). 5 Although several previous studies have examined nonlinear relations of BP to cognition, 7-9 few domains of cognitive function were measured (ie, global mental status, verbal memory, perceptuomotor speed), there was limited assessment of effect modification, and persons with stroke or dementia were included (which may lead to overestimation of BP-cognition relations). Here, we examined measures of verbal and nonverbal memory, attention, perceptuo-motor speed, executive functions, and confrontation naming, and potential interactions of BP with several demographic and lifestyle variables.

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.…”

“…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.…”

Ausência de relação entre hipertensão arterial sistêmica e desempenho cognitivo em idosos de uma comunidade

“…Ao contrário de alguns relatos [5][6][7][8] , neste estudo não foi encontrada relação estatisticamente significativa entre hipertensão arterial e declínio cognitivo. Conforme o esperado, as análises demonstraram que os níveis mais baixos de desempenho cognitivo foram encontrados em indivíduos mais velhos e com menor escolaridade.…”

“…Alguns estudos longitudinais [5][6][7][8] encontraram relação significativa entre a hipertensão arterial sistêmica e o declínio cognitivo em idosos, por outro lado, outros estudos, também longitudinais, não encontraram essa relação 9,10 .…”

Relationship between the diagnostic components of metabolic syndrome (MS) and cognition by ApoE genotype in the elderly

“…Until recently, certain studies reported that cognitive impairment in the elderly was more severe for those with MS (Kalmijn et al, 2000;Yaffe et al, 2004). Individual diagnostic components for MS including hypertension (Haan et al, 1999;Hebert et al, 2004;Qiu et al, 2005;Waldstein et al, 2005), diabetes (Elias et al, 1997;Stewart and Liolitsa, 1999), dyslipidemia (Isbir et al, 2001;Yaffe et al, 2002), and obesity (Jeong et al, 2005) have been shown to increase the risk of dementia or cognitive impairment. Furthermore, the respective effects of each component on cognitive function reportedly differ according to the ApoE genotype (Haan et al, 1999;Stewart and Liolitsa, 1999;Isbir et al, 2001;Yaffe et al, 2002).…”