Treating blood pressure to prevent strokes: The age factor

A New Perspective on Stroke Research: Unraveling the Role of Brain Oxygen Dynamics in Stroke Pathophysiology

Stroke, a leading cause of death and disability, often results from ischemic events that cut off the brain blood flow, leading to neuron death. Despite treatment advancements, survivors frequently endure lasting impairments. A key focus is the ischemic penumbra, the area around the stroke that could potentially recover with prompt oxygenation; yet its monitoring is complex. Recent progress in bioluminescence-based oxygen sensing, particularly through the Green enhanced Nano-lantern (GeNL), offers unprecedented views of oxygen fluctuations in vivo. Utilized in awake mice, GeNL has uncovered hypoxic pockets within the cerebral cortex, revealing the brain's oxygen environment as a dynamic landscape influenced by physiological states and behaviors like locomotion and wakefulness. These findings illuminate the complexity of oxygen dynamics and suggest the potential impact of hypoxic pockets on ischemic injury and recovery, challenging existing paradigms and highlighting the importance of microenvironmental oxygen control in stroke resilience. This review examines the implications of these novel findings for stroke research, emphasizing the criticality of understanding pre-existing oxygen dynamics for addressing brain ischemia. The presence of hypoxic pockets in non-stroke conditions indicates a more intricate hypoxic scenario in ischemic brains, suggesting strategies to alleviate hypoxia could lead to more effective treatments and rehabilitation. By bridging gaps in our knowledge, especially concerning microenvironmental changes post-stroke, and leveraging new technologies like GeNL, we can pave the way for therapeutic innovations that significantly enhance outcomes for stroke survivors, promising a future where an understanding of cerebral oxygenation dynamics profoundly informs stroke therapy.

Predictive Role of Child-To-Adult Blood Pressure Trajectories for Incident Metabolic Syndrome: 30-Year Hanzhong Adolescent Hypertension Study

OBJECTIVE

The relationship between child-to-adult blood pressure (BP) trajectories and metabolic syndrome (MetS) is unknown. We aimed to determine the predictive role of BP trajectories for incident MetS and its components.

METHODS

The prospective Hanzhong Adolescent Hypertension study began in 1987 and included 2692 participants free of MetS at baseline with at least 3 BP measurements available from 1987 to 2017.

RESULTS

The systolic BP (SBP) trajectory patterns were grouped as normal (class 1, 18.7%), high normal (class 2, 60.3%), prehypertensive (class 3, 13.1%), stage 1 hypertensive (class 4, 5.7%), and stage 2 hypertensive (class 5, 2.2%). Compared with those in the normal group, individuals in classes 2 to 5 had significantly higher risks of MetS (all Ps < .05), and those with hypertension had more than an 8-fold higher risk of MetS (both P < .05). The fully adjusted risk ratios (RRs) of central obesity increased significantly in a stepwise manner as the SBP trajectory group increased from class 1 to class 5 (P < .05). Compared with those with a normal SBP trajectory, participants in the prehypertensive group and stage 1 and stage 2 hypertensive groups had significantly higher RRs for high-risk triglycerides after full adjustment (RR = 1.89 [1.22-2.94]; RR = 3.61 [2.16-6.02]; and RR = 3.22 [1.52-6.84], respectively).

CONCLUSION

Our study suggests that BP trajectories are predictive of incident MetS outcomes. Early detection of hypertension or modest elevations in BP is crucial. The stage of hypertension based on SBP level showed a greater association with central obesity.

Influence of age and gender on blood pressure variability and baroreflex sensitivity in a healthy population in the Indian sub-continent

Background The current exploratory study was aimed at estimating measures of blood pressure variability (BPV) and baroreflex sensitivity (BRS) in a healthy population in the Indian sub-continent. Methods One hundred and forty-two healthy subjects were recruited for the study. Blood pressure (BP) was recorded continuously for 15 min using the Finometer (Finapres Medical Systems, The Netherlands). For offline analysis, Nevrokard cardiovascular parameter analysis (CVPA) software (version 2.1.0) was used for BPV analysis. BRS was determined by spectral and sequence methods. One-way ANOVA and Bonferroni's test were used to compare parameters. Pearson's correlation coefficient was employed to look for possible associations between age and other continuous variables. Results Out of 196 screened volunteers, 54 were excluded and 142 subjects were grouped based on ages as 10-19 years (group 1), 20-29 years (group 2), 30-39 years (group 3), 40-49 years (group 4), and 50-59 years (group 5). Within groups, body mass index (BMI, p=0.000) and BP (systolic and diastolic) were significantly different. Post hoc analysis showed mean blood pressure (MBP) and diastolic blood pressure (DBP) differing significantly between groups 1 and 4 (p<0.05 for both) along with other cardiovascular parameters. Age correlated positively with BMI and all parameters of BP. Significant gender differences were observed for stroke volume, cardiac output, up BRS, total BRS, peripheral resistance (PR), and aortic impedance. Conclusions Our study has provided reference values for BPV and BRS in an Indian population. It also indicates age-related neurocardiac imbalance and possible utility of these tests for screening at the start of neurocardiac damage in a healthy population.

Identification of Normal Blood Pressure in Different Age Group

The concept of using single criterion of normal blood pressure with systolic blood pressure (SBP) < 140 mmHg and diastolic blood pressure (DBP) < 90 mmHg for all ages is still disputable. The aim of the study is to identify the cutoff value of normotension in different age and sex groups.Totally, 127,922 (63,724 men and 64,198 women) were enrolled for the analysis. Finally, four fifths of them were randomly selected as the study group and the other one fifths as the validation group. Due the tight relationship with comorbidities from cardiovascular disease (CVD), metabolic syndrome (MetS) was used as a surrogate to replace the actual cardiovascular outcomes in the younger subjects.For SBP, MetS predicted by our equation had a sensitivity of 55% and specificity of 67% in males and 65%, 83% in females, respectively. At the same time, they are 61%, 73% in males and 73%, 86% in females for DBP, respectively. These sensitivity, specificity, odds ratio, and area under the receiver operating characteristic curve from our equations are all better than those derived from the criteria of 140/90 or 130/85 mmHg in both genders.By using the presence of MetS as the surrogate of CVD, the regression equations between SBP, DBP, and age were built in both genders. These new criteria are proved to have better sensitivity and specificity for MetS than either 140/90 or 130/85 mmHg. These simple equations should be used in clinical settings for early prevention of CVD.

PCSK9 variation and association with blood pressure in African Americans: preliminary findings from the HyperGEN and REGARDS studies

Proprotein convertase subtilisin/kexin type 9 (encoded by PCSK9) plays a well-known role in the regulation of low-density lipoprotein (LDL) receptors, and an inhibitor of this enzyme is a promising new therapeutic for hyperlipidemia. Recently, animal and human studies also implicate PCSK9 genetic variation in the regulation of blood pressure. The goal of this study was to examine if common and rare polymorphisms in PCSK9 are associated with blood pressure in an African-American population at high risk for cardiovascular disease. Using genomic data assayed on the Affymetrix 6.0 array (n = 1199) and the Illumina HumanExome Beadchip (n = 1966) from the Hypertension Genetic Epidemiology Network (HyperGEN), we tested the association of PCSK9 polymorphisms with blood pressure. We used linear mixed models and the sequence kernel association test (SKAT) to assess the association of 31 common and 19 rare variants with blood pressure. The models were adjusted for age, sex, center, smoking status, principal components for ancestry and diabetes as fixed effects and family as a random effect. The results showed a marginally significant effect of two genome-wide association study (GWAS) single-nucleotide polymorphisms (SNPs) (rs12048828: β = 1.8, P = 0.05 and rs9730100: β = 1.0, P = 0.05) with diastolic blood pressure (DBP); however these results were not significant after correction for multiple testing. Rare variants were cumulatively associated with DBP (P = 0.04), an effect that was strengthened by restriction to non-synonymous or stop-gain SNPs (P = 0.02). While gene-based results for DBP did not replicate (P = 0.36), we found an association with SBP (P = 0.04) in the Reasons for Geographic And Racial Differences in Stroke study (REGARDS). The findings here suggest rare variants in PCSK9 may influence blood pressure among African Americans, laying the ground work for further validation studies.

Prevalência de hipertensão arterial sistêmica em idosos no Brasil entre 2006 e 2010

Objetivo: observar a evolução da prevalência de hipertensão arterial sistêmica (HAS) em idosos entre 2006 e 2010 no Brasil. Métodos: estudo descritivo, ecológico, quantitativo, de um período entre 2006 e 2010, com dados coletados do Departamento de Informática do Sistema Único de Saúde (DATASUS) relacionados ao sexo, região e escolaridade na faixa etária de 65 anos ou mais.  Resultados: na análise entre regiões brasileiras, não houve diferença significativa nos anos analisados. Na comparação entre os sexos, a prevalência de HAS acima de 65 anos nas mulheres foi maior que nos homens. Com relação ao nível de escolaridade, foi encontrado que a prevalência no ano de 2006 foi significativamente menor do que nos anos de 2008 e 2009 entre pessoas com 9 a 11 anos de educação formal. Entre as regiões, quanto menor o nível de escolaridade, maior a prevalência de hipertensão. Conclusão: a prevalência da HAS acima dos 65 anos não seguiu uma tendência linear, mas manteve-se elevada, com predomínio em idosos do sexo feminino e em idosos com baixa escolaridade, chamando a atenção para a necessidade de ações de prevenção dos fatores de risco e acompanhamento em longo prazo dos idosos hipertensos.