Long-term prevention of ischaemic stroke and stroke recurrence

Cognitive Function is a Predictor of the Daily Step Count in Patients With Subacute Stroke With Independent Walking Ability: A Prospective Cohort Study

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Cognition at admission may predict daily step count.

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Cognitive impairment may increase risk of poor ambulation after subacute stroke.

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Ambulation poststroke is influenced by both physical and cognitive factors.

Objectives

To investigate the physical, cognitive, and psychological factors related to daily step count in patients with subacute stroke.

Design

Prospective cohort study.

Setting

A subacute rehabilitation ward with 160 beds.

Participants

Patients with subacute stroke who could walk independently (N=101). Among the 101 participants enrolled in this study (mean age, 64.5±13.5y), 64.4% (n=65) were men and 69.3% (n=70) were patients with cerebral infarction.

Interventions

We assessed ambulatory activity using a pedometer placed in the pants pocket on the nonparalyzed side continuously for 7 consecutive days. We also obtained demographic and clinical information and recorded the following measurement scores: Stroke Impairment Assessment Set, FIM, Mini-Mental State Examination (MMSE), Self-Rating Depression Scale, and Apathy Scale. All measurements were collected at admission and discharge.

Main Outcome Measures

The outcomes assessed were ambulatory activity, motor and sensory functions, functional disability, cognitive function, depressive symptoms, and motivation.

Results

The median daily steps ambulated at admission and discharge were 5584 steps (interquartile range, 3763-7096 steps) and 5991 steps (interquartile range, 4329-8204 steps), respectively. In the univariate regression analysis, age, sex, serum albumin level, affected side of the brain, and MMSE score at admission were significantly associated with the daily step count at discharge. Multiple regression analysis using these 5 items as independent variables revealed that the MMSE score at admission (reference, 28-30 points; B, −2.07; 95% confidence interval, −3.89 to −0.35; β, −0.22; P=.027) was significantly associated with the daily step count at discharge.

Conclusions

Cognitive function at admission had a significant association with the daily step count at discharge in patients with subacute stroke who could walk independently.

Genetic Deletion of Krüppel-Like Factor 11 Aggravates Ischemic Brain Injury

Krüppel-like factors (KLFs) belong to the zinc finger family of transcription factors, and their function in the CNS is largely unexplored. KLF11 is a member of the KLF family, and we have previously demonstrated that peroxisome proliferator-activated receptor gamma-mediated cerebral protection during ischemic insults needs recruitment of KLF11 as its critical coactivator. Here, we sought to determine the role of KLF11 itself in cerebrovascular function and the pathogenesis of ischemic stroke. Transient middle cerebral artery occlusion (MCAO) was performed in KLF11 knockout and wild-type control mice, and brain infarction was analyzed by TTC staining. BBB integrity was assessed by using Evans Blue and TMR-Dextran extravasation assays. KLF11 KO mice exhibited significantly larger brain infarction and poorer neurological outcomes in response to ischemic insults. Genetic deficiency of KLF11 in mice also significantly aggravated ischemia-induced BBB disruption by increasing cerebrovascular permeability and edema. Mechanistically, KLF11 was found to directly regulate IL-6 in the brains of ischemic mice. These findings suggest that KLF11 acts as a novel protective factor in ischemic stroke. Elucidating the functional importance of KLF11 in ischemia may lead us to discover novel pharmacological targets for the development of effective therapies against ischemic stroke.

Krüpple-like factors in the central nervous system: novel mediators in stroke

Transcription factors play an important role in the pathophysiology of many neurological disorders, including stroke. In the past three decades, an increasing number of transcription factors and their related gene signaling networks have been identified, and have become a research focus in the stroke field. Krüppel-like factors (KLFs) are members of the zinc finger family of transcription factors with diverse regulatory functions in cell growth, differentiation, proliferation, migration, apoptosis, metabolism, and inflammation. KLFs are also abundantly expressed in the brain where they serve as critical regulators of neuronal development and regeneration to maintain normal brain function. Dysregulation of KLFs has been linked to various neurological disorders. Recently, there is emerging evidence that suggests KLFs have an important role in the pathogenesis of stroke and provide endogenous vaso-or neuro-protection in the brain's response to ischemic stimuli. In this review, we summarize the basic knowledge and advancement of these transcriptional mediators in the central nervous system, highlighting the novel roles of KLFs in stroke.

Prestroke factors associated with poststroke mortality and recovery in older women in the Women's Health Initiative

OBJECTIVES

To examine prestroke lifestyle factors associated with poststroke mortality and recovery in older women.

DESIGN

Longitudinal prospective cohort study.

SETTING

The Women's Health Initiative (WHI, clinical trials and observational study), 40 clinical centers in the United States.

PARTICIPANTS

WHI participants, women aged 50 to 79, who were stroke-free at baseline (1993/98), with incident stroke before 2005.

MEASUREMENTS

Participants were followed for mortality through 2010. Prestroke characteristics were from the last examination before the stroke event. Annual follow-up for clinical events ascertained hospitalization for stroke that was subsequently physician adjudicated with medical records. Multivariable regression models were used to analyze factors associated with poststroke mortality and poststroke recovery at hospital discharge (poststroke Glasgow score), adjusting for stroke type.

RESULTS

Of 3,173 women with incident stroke, 1,111 (35%) died. Individuals who were overweight or obese before stroke had lower poststroke mortality than those who were normal weight (obese: hazard ratio (HR) = 0.69, 95% confidence interval (CI) = 0.53-0.88; overweight: HR = 0.72, 95% CI = 0.58-0.90); individuals who were underweight before stroke had nonsignificantly greater poststroke mortality (HR = 2.02, 95% CI = 0.98-4.16, P = .06). Other prestroke factors associated with poststroke mortality included diabetes mellitus (HR = 1.28, 95% CI = 1.01-1.64), current smoking (vs nonsmoker, HR = 2.13, 95% CI = 1.53-3.00), physical inactivity (vs >150 min of exercise per week, HR = 1.39, 95% CI = 1.09-1.78), and lowest physical function quartile (vs highest, HR = 1.54, 95% CI = 1.18-2.02). Prestroke diabetes mellitus was associated with lower odds of good recovery after stroke (odds ratio (OR) = 0.60, 95% CI = 0.44-0.82). Current hormone use before stroke was associated with greater odds of moderate than of severe disability after stroke (OR = 1.29, 95% CI = 1.00-1.66).

CONCLUSION

Potentially modifiable factors before stroke, including smoking, diabetes mellitus, and being underweight, were associated with greater poststroke mortality in older women. Being overweight or obese and physical activity before stroke were associated with lower poststroke mortality in older women.

What are the patient-held illness beliefs after a transient ischaemic attack, and do they determine secondary prevention activities: an exploratory study in a North London General Practice

BACKGROUND

A transient ischaemic attack (TIA) is a strong predictor of future stroke. Stroke is the most common cause of mortality in the United Kingdom. Management of risk factors can reduce the possibility of future strokes; however, these are often difficult to achieve optimally. Current evidence suggests that beliefs about causal attributions, severity and perceived risk of stroke may influence uptake of secondary prevention activities amongst this patient group.

AIM

To explore the illness beliefs of patients about TIAs and future risk of stroke, and to determine whether these beliefs determine secondary stroke prevention activities.

METHOD

A qualitative study comprising face-to-face, semi-structured interviews conducted in the homes of participants. Sampling was purposive and drawn from a single North London General Practice. A thematic framework analysis method was followed.

FINDINGS

Eleven participants took part in the study (aged 46-86 years, three female participants and eight male participants). Time since diagnosis ranged from 2 to 25 years. There was a commonly held belief that TIAs are 'short-lived events' associated with full recovery, whereas strokes always lead to permanent 'disability'. Only those who believed their TIAs to be 'serious' undertook activities to prevent further recurrence. Concordance with medication was the most popular prevention activity.

CONCLUSION

The traditional medical definition of TIA and stroke do not reflect the views of patients who have had TIAs. One's perception of the severity of the initial TIA event and the risk of future stroke episodes may influence the uptake of secondary stroke prevention activities. Post TIA stroke prevention interventions should include tailored discussions focussing on the importance of the acute event and its implications for long-term health and future stroke risk.

Tissue adaptation to physical stress: a proposed "Physical Stress Theory" to guide physical therapist practice, education, and research

The purpose of this perspective is to present a general theory--the Physical Stress Theory (PST). The basic premise of the PST is that changes in the relative level of physical stress cause a predictable adaptive response in all biological tissue. Specific thresholds define the upper and lower stress levels for each characteristic tissue response. Qualitatively, the 5 tissue responses to physical stress are decreased stress tolerance (eg, atrophy), maintenance, increased stress tolerance (eg, hypertrophy), injury, and death. Fundamental principles of tissue adaptation to physical stress are described that, in the authors' opinion, can be used to help guide physical therapy practice, education, and research. The description of fundamental principles is followed by a review of selected literature describing adaptation to physical stress for each of the 4 main organ systems described in the Guide to Physical Therapist Practice (ie, cardiovascular/pulmonary, integumentary, musculoskeletal, neuromuscular). Limitations and implications of the PST for practice, research, and education are presented.