Measurement of resistance-area product by transcranial Doppler: An alternative tool for cognitive screening in hypertensive on drug treatment?

Introduction: Arterial hypertrophy and remodeling are adaptive responses present in systemic arterial hypertension that can result in silent ischemia and neurodegeneration, compromising brain connections and cognitive performance (CP). However, CP is affected differently over time, so traditional screening methods may become less sensitive in assessing certain cognitive domains. The study aimed to evaluate whether cerebrovascular hemodynamic parameters can serve as a tool for cognitive screening in hypertensive without clinically manifest cognitive decline. Methods: Participants were allocated into groups: non-hypertensive (n = 30) [group 1], hypertensive with systolic blood pressure (SBP) < 140 and diastolic blood pressure (DBP) < 90 mmHg (n = 54) [group 2] and hypertensive with SBP ≥ 140 or DBP ≥ 90 (n = 31) [group 3]. Measurements of blood pressure and middle cerebral artery blood flow velocity were obtained from digital plethysmography and transcranial Doppler. For the cognitive assessment, the Mini Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA) and a broad neuropsychological battery were applied. Results: Patients in groups 2 and 3 show no significant differences in most of the clinical-epidemiological variables or pulsatility index (p = 0.361), however compared to group 1 and 2, patients in group 3 had greater resistance-area product [RAP] (1.7 [±0.7] vs. 1.2 [±0.2], p < 0.001). There was a negative correlation between RAP, episodic memory (r = -0.277, p = 0.004) and cognitive processing speed (r = -0.319, p = 0.001). Conclusion: RAP reflects the real cerebrovascular resistance, regardless of the direct action of antihypertensive on the microcirculation, and seems to be a potential alternative tool for cognitive screening in hypertensive.

Evaluation of cerebral autoregulation performance in patients with arterial hypertension on drug treatment.

Cerebral autoregulation (AR) keeps cerebral blood flow constant despite fluctuations in systemic arterial pressure. The final common AR pathway is made up of vasomotor adjustments of cerebrovascular resistance mediated by arterioles. Structural and functional changes in the arteriolar wall arise with age and systemic arterial hypertension. This study evaluated whether AR is impaired in hypertensive patients and whether this impairment differs with disease control. Three groups of patients were prospectively compared: hypertensive patients under treatment with systolic blood pressure (SBP) <140 and diastolic blood pressure (DBP) <90 mm Hg (n = 54), hypertensive patients under treatment with SBP > 140 or DBP > 90 mm Hg (n = 31), and normotensive volunteers (n = 30). Simultaneous measurements of cerebral blood flow velocity (CBFV) and BP were obtained by digital plethysmography and transcranial Doppler, and the AR index (ARI) was defined according to the step response to spontaneous fluctuations in BP. Compared to the uncontrolled hypertension, the normotensive individuals were younger (age 43.42 ± 11.14, P < .05) and had a lower resistance-area product (1.17 ± 0.24, P < .05), although age and greater arteriolar stiffness did not affect the CBFV mean of hypertensive patients, whether controlled or uncontrolled (62.85 × 58.49 × 58.30 cm/s, P = .29), most likely because their ARIs were not compromised (5.54 × 5.91 × 5.88, P = .6). Hypertensive patients under treatment, regardless of their BP control, have intact AR capacity.

Systemic arterial hypertension and cognition in adults: effects on executive functioning.

BACKGROUND: Central nervous system changes associated to systemic arterial hypertension (SAH) are progressive and may cause negative effects on cognitive performance. The objective of this study was to investigate the relation between SAH and the components of executive functions (EF), inhibitory control (IC), updating and shifting, comparing a control group (without SAH) to patients with SAH, in two levels of severity. METHODS: The protocol included the following tests to evaluate EF components: T.O.V.A. Test (IC), Backward Digit Span from Wechsler Adults Intelligence Scale (WAIS-III), Phonemic and Semantic Verbal Fluency (updating), and Trail Making Test Part B (shifting). RESULTS: A total of 204 participants was included: 56 from the Control Group (CG), 87 SAH stage 1, and 61 SAH stage 2. The groups were not different for age (52.37±12.29) and education (10.98±4.06). As to controlled blood pressure (BP), duration of hypertension treatment and number of drugs, the SAH 2 group had a worse BP control, longer duration of hypertension treatment and use of more drugs when compared to the SAH 1. The findings revealed that patients with more severe hypertension presented worse performance in updating (Backward Digit Span, phonemic and semantics VF) and shifting (Trail Making Test Part B). CONCLUSION: The results suggest that patients with SAH have a significant impairment in EF, more specifically in updating and shifting. Besides that, such damage may be directly proportional to the severity of SAH. It is suggested that future studies include neuroimaging exams to exclude possible cerebrovascular diseases.

Systemic arterial hypertension and cognition in adults: effects on executive functioning / Hipertensão arterial sistêmica e cognição em adultos: efeitos no funcionamento executivo

ABSTRACT Background: Central nervous system changes associated to systemic arterial hypertension (SAH) are progressive and may cause negative effects on cognitive performance. The objective of this study was to investigate the relation between SAH and the components of executive functions (EF), inhibitory control (IC), updating and shifting, comparing a control group (without SAH) to patients with SAH, in two levels of severity. Methods: The protocol included the following tests to evaluate EF components: T.O.V.A. Test (IC), Backward Digit Span from Wechsler Adults Intelligence Scale (WAIS-III), Phonemic and Semantic Verbal Fluency (updating), and Trail Making Test Part B (shifting). Results: A total of 204 participants was included: 56 from the Control Group (CG), 87 SAH stage 1, and 61 SAH stage 2. The groups were not different for age (52.37±12.29) and education (10.98±4.06). As to controlled blood pressure (BP), duration of hypertension treatment and number of drugs, the SAH 2 group had a worse BP control, longer duration of hypertension treatment and use of more drugs when compared to the SAH 1. The findings revealed that patients with more severe hypertension presented worse performance in updating (Backward Digit Span, phonemic and semantics VF) and shifting (Trail Making Test Part B). Conclusion: The results suggest that patients with SAH have a significant impairment in EF, more specifically in updating and shifting. Besides that, such damage may be directly proportional to the severity of SAH. It is suggested that future studies include neuroimaging exams to exclude possible cerebrovascular diseases.

RESUMO Introdução: As alterações do sistema nervoso central associadas à hipertensão arterial sistêmica (HAS) são progressivas e podem ocasionar efeitos negativos no desempenho cognitivo. O objetivo deste estudo foi investigar a relação entre a HAS e os componentes das funções executivas (FE), controle inibitório (CI), atualização e alternância, comparando um grupo controle (sem HAS) a pacientes com HAS, em dois níveis de gravidade. Métodos: O protocolo incluiu os seguintes testes para avaliar os componentes das FE: T.O.V.A. Test (CI), Dígitos Ordem Indireta da Escala de Inteligência Wechsler para Adultos (Wechsler Adults Intelligence Scale - WAIS-III), Fluência Verbal fonêmica e semântica (atualização) e Teste de Trilhas parte B (alternância). Resultados: Foram incluídos 204 participantes, sendo 56 do Grupo Controle (GC), 87 HAS estágio 1 (HAS 1) e 61 de HAS estágio 2 (HAS 2). Os grupos não foram diferentes em relação à idade (52,37±12,29) e escolaridade (10,98±4,06). Em relação à pressão arterial (PA) controlada, tempo de tratamento da HAS e número de medicações, o grupo HAS 2 apresentou pior controle de PA, mais tempo de tratamento da HAS e uso de maior número de medicações quando comparado ao grupo HAS 1. Os achados revelaram que os pacientes com HAS em estágio mais grave apresentaram pior desempenho nos testes de alternância (Teste de Trilhas parte B) e atualização (Dígitos Ordem Indireta, FV fonêmica e semântica). Conclusão: Esses resultados sugerem que pacientes com a HAS possuem prejuízo significativo em FE, especificamente em alternância e atualização, e que esse prejuízo pode ser diretamente proporcional à gravidade da HAS. Sugere-se que, em estudos futuros, incluam-se exames de neuroimagem com o objetivo de excluir possíveis doenças cerebrovasculares.

Impact of hypertension severity on arterial stiffness, cerebral vasoreactivity, and cognitive performance / Impacto da gravidade da hipertensão na rigidez arterial, vasorreatividade cerebral e desempenho cognitivo

ABSTRACT. Aging, hypertension (HTN), and other cardiovascular risk factors contribute to structural and functional changes of the arterial wall. Objective: To evaluate whether arterial stiffness (AS) is related to cerebral blood flow changes and its association with cognitive function in patients with hypertension. Methods: 211 patients (69 normotensive and 142 hypertensive) were included. Patients with hypertension were divided into 2 stages: HTN stage-1 and HTN stage-2. The mini-mental state examination (MMSE), Montreal Cognitive Assessment (MoCA) and a battery of neuropsychological (NPE) tests were used to determine cognitive function. Pulse wave velocity was measured using the Complior®. Carotid properties were assessed by radiofrequency ultrasound. Central arterial pressure and augmentation index were obtained using applanation tonometry. Middle cerebral artery flow velocity was measured by transcranial Doppler ultrasonography. Results: Both arterial stiffness parameters and cerebral vasoreactivity worsened in line with HTN severity. There was a negative correlation between breath holding index (BHI) and arterial stiffness parameters. Cognitive performance worsened in line with HTN severity, with statistical difference occurring mainly between the HTN-2 and normotension groups on both the MMSE and MoCA. The same tendency was observed on the NPE tests. Conclusion: Hypertension severity was associated with higher AS, worse BHI, and lower cognitive performance.

RESUMO. A idade, hipertensão arterial (HA), e outros fatores de risco cardiovascular contribuem para as alterações estruturais e funcionais da parede arterial. Objetivo: Avaliar o quanto a rigidez arterial está relacionada com as alterações do fluxo sanguíneo cerebral e sua associação com a função cognitiva em pacientes com hipertensão. Métodos: Foram incluídos 211 pacientes (69 normotensos e 142 hipertensos). Os pacientes com hipertensão foram divididos em dois estágios: HA-1 e HA-2. O mini exame do estado mental (MEEM), Montreal Cognitive Assessment (MoCA) e uma bateria de testes neuropsicológicos foram usados para avaliar a função cognitiva. A velocidade da onda de pulso foi medida usando o Complior®. As propriedades da artéria carótida foram avaliadas usando o ultrassom de radiofrequência. A pressão arterial central e o índice de incremento foram obtidos usando a tonometria de aplanação. A velocidade de fluxo sanguíneo da arterial cerebral média foi medida pelo ultrassom com Doppler Transcraniano. Resultados: Tanto os parâmetros da rigidez arterial quanto a vasorreatividade cerebral foram piores com a gravidade da hipertensão. Houve uma correlação negativa entre o índice de apnéia e os parâmetros da rigidez arterial. O desempenho cognitivo foi pior com a gravidade de hipertensão arterial com diferença estatística ocorrendo principalmente entre os grupos HA-2 e normotensão tanto no MEEM quanto no MoCA. A mesma tendência foi observada em relação aos testes neuropsicológicos. Conclusão: A gravidade de hipertensão arterial foi associada com maior rigidez arterial, pior índice de apneia, e menor desempenho cognitivo.

Impact of hypertension severity on arterial stiffness, cerebral vasoreactivity, and cognitive performance.

Aging, hypertension (HTN), and other cardiovascular risk factors contribute to structural and functional changes of the arterial wall. OBJECTIVE: To evaluate whether arterial stiffness (AS) is related to cerebral blood flow changes and its association with cognitive function in patients with hypertension. METHODS: 211 patients (69 normotensive and 142 hypertensive) were included. Patients with hypertension were divided into 2 stages: HTN stage-1 and HTN stage-2. The mini-mental state examination (MMSE), Montreal Cognitive Assessment (MoCA) and a battery of neuropsychological (NPE) tests were used to determine cognitive function. Pulse wave velocity was measured using the Complior®. Carotid properties were assessed by radiofrequency ultrasound. Central arterial pressure and augmentation index were obtained using applanation tonometry. Middle cerebral artery flow velocity was measured by transcranial Doppler ultrasonography. RESULTS: Both arterial stiffness parameters and cerebral vasoreactivity worsened in line with HTN severity. There was a negative correlation between breath holding index (BHI) and arterial stiffness parameters. Cognitive performance worsened in line with HTN severity, with statistical difference occurring mainly between the HTN-2 and normotension groups on both the MMSE and MoCA. The same tendency was observed on the NPE tests. CONCLUSION: Hypertension severity was associated with higher AS, worse BHI, and lower cognitive performance.

A idade, hipertensão arterial (HA), e outros fatores de risco cardiovascular contribuem para as alterações estruturais e funcionais da parede arterial. OBJETIVO: Avaliar o quanto a rigidez arterial está relacionada com as alterações do fluxo sanguíneo cerebral e sua associação com a função cognitiva em pacientes com hipertensão. MÉTODOS: Foram incluídos 211 pacientes (69 normotensos e 142 hipertensos). Os pacientes com hipertensão foram divididos em dois estágios: HA-1 e HA-2. O mini exame do estado mental (MEEM), Montreal Cognitive Assessment (MoCA) e uma bateria de testes neuropsicológicos foram usados para avaliar a função cognitiva. A velocidade da onda de pulso foi medida usando o Complior®. As propriedades da artéria carótida foram avaliadas usando o ultrassom de radiofrequência. A pressão arterial central e o índice de incremento foram obtidos usando a tonometria de aplanação. A velocidade de fluxo sanguíneo da arterial cerebral média foi medida pelo ultrassom com Doppler Transcraniano. RESULTADOS: Tanto os parâmetros da rigidez arterial quanto a vasorreatividade cerebral foram piores com a gravidade da hipertensão. Houve uma correlação negativa entre o índice de apnéia e os parâmetros da rigidez arterial. O desempenho cognitivo foi pior com a gravidade de hipertensão arterial com diferença estatística ocorrendo principalmente entre os grupos HA-2 e normotensão tanto no MEEM quanto no MoCA. A mesma tendência foi observada em relação aos testes neuropsicológicos. CONCLUSÃO: A gravidade de hipertensão arterial foi associada com maior rigidez arterial, pior índice de apneia, e menor desempenho cognitivo.

Psychometric characteristics of the Rivermead Behavioural Memory Test (RBMT) as an early detection instrument for dementia and mild cognitive impairment in Brazil.

BACKGROUND: The Rivermead Behavioural Memory Test (RBMT) assesses everyday memory by means of tasks which mimic daily challenges. The objective was to examine the validity of the Brazilian version of the RBMT to detect cognitive decline. METHODS: 195 older adults were diagnosed as normal controls (NC) or with mild cognitive impairment (MCI) or Alzheimer's disease (AD) by a multidisciplinary team, after participants completed clinical and neuropsychological protocols. RESULTS: Cronbach's alpha was high for the total sample for the RBMT profile (PS) and screening scores (SS) (PS = 0.91, SS = 0.87) and for the AD group (PS = 0.84, SS = 0.85), and moderate for the MCI (PS = 0.62, SS = 0.55) and NC (PS = 0.62, SS = 0.60) groups. RBMT total scores, Appointment, Pictures, Immediate and Delayed Story, Immediate and Delayed Route, Delayed Message and Date contributed to differentiate NC from MCI. ROC curve analyses indicated high accuracy to differentiate NC from AD patients, and, moderate accuracy to differentiate NC from MCI. CONCLUSIONS: The Brazilian version of the RBMT seems to be an appropriate instrument to identify memory decline in Brazilian older adults.

Diagnostic transitions in mild cognitive impairment subtypes.

BACKGROUND: At least for a subset of patients, the clinical diagnosis of mild cognitive impairment (MCI) may represent an intermediate stage between normal aging and dementia. Nevertheless, the patterns of transition of cognitive states between normal cognitive aging and MCI to dementia are not well established. In this study we address the pattern of transitions between cognitive states in patients with MCI and healthy controls, prior to the conversion to dementia. METHODS: 139 subjects (78% women, mean age, 68.5 +/- 6.1 years; mean educational level, 11.7 +/- 5.4 years) were consecutively assessed in a memory clinic with a standardized clinical and neuropsychological protocol, and classified as cognitively healthy (normal controls) or with MCI (including subtypes) at baseline. These subjects underwent annual reassessments (mean duration of follow-up: 2.7 +/- 1.1 years), in which cognitive state was ascertained independently of prior diagnoses. The pattern of transitions of the cognitive state was determined by Markov chain analysis. RESULTS: The transitions from one cognitive state to another varied substantially between MCI subtypes. Single-domain MCI (amnestic and non-amnestic) more frequently returned to normal cognitive state upon follow-up (22.5% and 21%, respectively). Among subjects who progressed to Alzheimer's disease (AD), the most common diagnosis immediately prior conversion was multiple-domain MCI (85%). CONCLUSION: The clinical diagnosis of MCI and its subtypes yields groups of patients with heterogeneous patterns of transitions between one given cognitive state to another. The presence of more severe and widespread cognitive deficits, as indicated by the group of multiple-domain amnestic MCI may be a better predictor of AD than single-domain amnestic or non-amnestic deficits. These higher-risk individuals could probably be the best candidates for the development of preventive strategies and early treatment for the disease.