RECENT FINDINGS: Methods of acquisition and analysis of BPV and cognitive measurements and their relationship were extracted from selected articles. Of 656 studies identified, 53 articles were selected. Twenty-five evaluated long-term (LTBPV), nine mid-term (MTBPV), 12 short-term (STBPV) and nine very short-term BPV (VSTBPV) with conflicting findings on the relationship between BPV and cognition. Variations existed in devices, period and procedure for acquisition. The studies also utilized a wide range of methods of BPV calculation. Thirteen cognitive assessment tools were used to measure global cognition or domain functions which were influenced by the population of interest. The interpretation of available studies was hence limited by heterogeneity. There is an urgent need for standardization of BPV assessments to streamline research on BPV and cognition. Future studies should also establish whether BPV could be a potential modifiable risk factor for cognitive decline, as well as a marker for treatment response.
METHODS: Cross-sectional analysis of the Malaysian Elders Longitudinal Research (MELoR) study involving community-dwelling individuals aged >55 years was conducted. Information on sociodemographic factors, medical history, and lifestyle were obtained by computer-assisted interviews in participants' homes. Cognitive performance was assessed with the Montreal Cognitive Assessment (MoCA) tool during subsequent hospital-based health checks. Hierarchical multiple linear regression analyses were conducted with continuous MoCA scores as the dependent variable.
RESULTS: Data were available for 1,140 participants, mean (standard deviation [SD]) = 68.48 (7.23) years, comprising 377 (33.1%) ethnic Malays, 414 (36.3%) Chinese, and 349 (30.6%) Indians. Mean (SD) MoCA scores were 20.44 (4.92), 23.97 (4.03), and 22.04 (4.83) for Malays, Chinese, and Indians, respectively (p = 0.01). Age >75 years, <12 years of education, and low functional ability were common risk factors for low cognitive performance across all three ethnic groups. Cognitive performance was positively associated with social engagement among the ethnic Chinese (β [95% CI] = 0.06 [0.01, 0.11]) and Indians (β [95% CI] = 0.16 [0.09, 0.23]) and with lower depression scores (β [(95% CI] = -0.08 [-0.15, -0.01]) among the ethnic Indians.
CONCLUSION: Common factors associated with cognitive performance include age, education, and functional ability, and ethnic-specific factors were social engagement and depression. Interethnic comparisons of risk factors may form the basis for identification of ethnic-specific modifiable risk factors for cognitive decline and provision of culturally acceptable prevention measures.
METHODS: Data was obtained from the Malaysian Elders Longitudinal Research (MELoR) study, which employed random stratified sampling from three parliamentary constituencies within the Klang Valley. Beat-to-beat blood pressure (BP) was recorded using non-invasive BP monitoring (TaskforceTM, CNSystems). Low frequency (LF), high frequency (HF) and low-to-high frequency (LF:HF) ratio for BPV were derived using fast Fourier transformation. Cognition was evaluated using the Montreal Cognitive Assessment (MoCA) test, and categorized into normal aging, mild impairment and moderate-to-severe impairment.
RESULTS: Data from 1,140 individuals, mean age (SD) 68.48 (7.23) years, were included. Individuals with moderate-to-severe impairment had higher HF-BPV for systolic (SBP) and diastolic (DBP) blood pressure compared to individuals within the normal aging group [OR (95% CI) = 2.29 (1.62-3.24)] and [OR (95% CI) = 1.80 (1.32-2.45)], while HF-SBPV [OR (95% CI) = 1.41 (1.03-1.93)] but not HF-DBPV was significantly higher with mild impairment compared to normal aging after adjustments for potential confounders. Moderate-to-severe impairment was associated with significantly lower LF:HF-SBPV [OR (95% CI) = 0.29 (0.18-0.47)] and LF:HF-DBPV [OR (95% CI) = 0.49 (0.34-0.72)], while mild impairment was associated with significantly lower LF:HF-SBPV [OR (95% CI) = 0.52 (0.34-0.80)] but not LF:HF-DBPV [OR (95% CI) = 0.81 (0.57-1.17)], compared to normal aging with similar adjustments.
CONCLUSION: Higher HF-BPV, which indicates parasympathetic activation, and lower LF:HF-BPV, which addresses sympathovagal balance, were observed among individuals with moderate-to-severe cognitive impairment. Future studies should determine whether BPV could be a physiological marker or modifiable risk factor for cognitive decline.