Browsing by Subject "Hypotension"

Now showing 1 - 3 of 3
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    ItemOpen Access
    A U-shaped Association Between Blood Pressure and Cognitive Impairment in Chinese Elderly.
    (Journal of the American Medical Directors Association, 2017-02) Lv, Yue-Bin; Zhu, Peng-Fei; Yin, Zhao-Xue; Kraus, Virginia Byers; Threapleton, Diane; Chei, Choy-Lye; Brasher, Melanie Sereny; Zhang, Juan; Qian, Han-Zhu; Mao, Chen; Matchar, David Bruce; Luo, Jie-Si; Zeng, Yi; Shi, Xiao-Ming

    Objectives

    Higher or lower blood pressure may relate to cognitive impairment, whereas the relationship between blood pressure and cognitive impairment among the elderly is not well-studied. The study objective was to determine whether blood pressure is associated with cognitive impairment in the elderly, and, if so, to accurately describe the association.

    Design

    Cross-sectional data from the sixth wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) conducted in 2011.

    Setting

    Community-based setting in longevity areas in China.

    Participants

    A total of 7144 Chinese elderly aged 65 years and older were included in the sample.

    Measures

    Systolic blood pressures (SBP) and diastolic blood pressures (DBP) were measured, pulse pressure (PP) was calculated as (SBP) - (DBP) and mean arterial pressures (MAP) was calculated as 1/3(SBP) + 2/3(DBP). Cognitive function was assessed via a validated Mini-Mental State Examination (MMSE).

    Results

    Based on the results of generalized additive models (GAMs), U-shaped associations were identified between cognitive impairment and SBP, DBP, PP, and MAP. The cutpoints at which risk for cognitive impairment (MMSE <24) was minimized were determined by quadratic models as 141 mm Hg, 85 mm Hg, 62 mm Hg, and 103 mm Hg, respectively. In the logistic models, U-shaped associations remained for SBP, DBP, and MAP but not PP. Below the identified cutpoints, each 1-mm Hg decrease in blood pressure corresponded to 0.7%, 1.1%, and 1.1% greater risk in the risk of cognitive impairment, respectively. Above the cutpoints, each 1-mm Hg increase in blood pressure corresponded to 1.2%, 1.8%, and 2.1% greater risk of cognitive impairment for SBP, DBP, and MAP, respectively.

    Conclusion

    A U-shaped association between blood pressure and cognitive function in an elderly Chinese population was found. Recognition of these instances is important in identifying the high-risk population for cognitive impairment and to individualize blood pressure management for cognitive impairment prevention.
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    Acute Adverse Events After Spinal Cord Injury and Their Relationship to Long-term Neurologic and Functional Outcomes: Analysis From the North American Clinical Trials Network for Spinal Cord Injury.
    (Critical care medicine, 2019-11) Jiang, Fan; Jaja, Blessing NR; Kurpad, Shekar N; Badhiwala, Jetan H; Aarabi, Bizhan; Grossman, Robert G; Harrop, James S; Guest, Jim D; Schär, Ralph T; Shaffrey, Chris I; Boakye, Max; Toups, Elizabeth G; Wilson, Jefferson R; Fehlings, Michael G; North American Clinical Trials Network Collaborators

    Objectives

    There are few contemporary, prospective multicenter series on the spectrum of acute adverse events and their relationship to long-term outcomes after traumatic spinal cord injury. The goal of this study is to assess the prevalence of adverse events after traumatic spinal cord injury and to evaluate the effects on long-term clinical outcome.

    Design

    Multicenter prospective registry.

    Setting

    Consortium of 11 university-affiliated medical centers in the North American Clinical Trials Network.

    Patients

    Eight-hundred one spinal cord injury patients enrolled by participating centers.

    Interventions

    Appropriate spinal cord injury treatment at individual centers.

    Measurements and main results

    A total of 2,303 adverse events were recorded for 502 patients (63%). Penalized maximum logistic regression models were fitted to estimate the likelihood of neurologic recovery (ASIA Impairment Scale improvement ≥ 1 grade point) and functional outcomes in subjects who developed adverse events at 6 months postinjury. After accounting for potential confounders, the group that developed adverse events showed less neurologic recovery (odds ratio, 0.55; 95% CI, 0.32-0.96) and was more likely to require assisted breathing (odds ratio, 6.55; 95% CI, 1.17-36.67); dependent ambulation (odds ratio, 7.38; 95% CI, 4.35-13.06) and have impaired bladder (odds ratio, 9.63; 95% CI, 5.19-17.87) or bowel function (odds ratio, 7.86; 95% CI, 4.31-14.32) measured using the Spinal Cord Independence Measure subscores.

    Conclusions

    Results from this contemporary series demonstrate that acute adverse events are common and are associated with worsened long-term outcomes after traumatic spinal cord injury.
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    Hippocampal cellular loss after brief hypotension.
    (SpringerPlus, 2013-12) Chaparro, Rafael E; Quiroga, Carolina; Bosco, Gerardo; Erasso, Diana; Rubini, Alessandro; Mangar, Devanand; Parmagnani, Andrea; Camporesi, Enrico M
    Brief episodes of hypotension have been shown to cause acute brain damage in animal models. We used a rat hemorrhagic shock model to assess functional outcome and to measure the relative neuronal damage at 1, 4 and 14 days post-injury (3 min of hypotension). All rats underwent a neurological assessment including motor abilities, sensory system evaluation and retrograde memory at post-hypotensive insult. Brains were harvested and stained for Fluorojade C and Nissl. Stereology was used to analyze Fluorojade C and Nissl stained brain sections to quantitatively detect neuronal damage after the hypotensive insult. Statistical analysis was performed using Graphpad Prism 5 with the Bonferroni test at a 95% confidence interval after ANOVA. A Mixed Effect Model was used for the passive avoidance evaluation. Stereologically counted fluorojade positive cells in the hippocampus revealed significant differences in neuronal cell injury between control rats and rats that received 3 min of hypotension one day after insult. Quantification of Nissl positive neuronal cells showed a significant decrease in the number hippocampal cells at day 14. No changes in frontal cortical cells were evident at any time, no significative changes in neurological assessments as well. Our observations show that brief periods of hemorrhage-induced hypotension actually result in neuronal cell damage in Sprague-Dawley rats even if the extent of neuronal damage that was incurred was not significant enough to cause changes in motor or sensory behavior.