Body mass index and stroke: overweight and obesity less often associated with stroke recurrence

Sex differences in modifiable risk factors for stroke incidence and recurrence: the UCC-SMART study

BACKGROUND AND PURPOSE

Risk factors for stroke differ between women and men in general populations. However, little is known about sex differences in secondary prevention. We investigated if sex interacted with modifiable risk factors for stroke in a large arterial disease cohort.

METHODS

Within the prospective UCC-SMART study, 13,898 patients (35% women) with atherosclerotic disease or high-risk factor profile were followed up to 23 years for stroke incidence or recurrence. Hypertension, smoking, diabetes, overweight, dyslipidemia, high alcohol use, and physical inactivity were studied as risk factors. Association between these factors and ischemic and hemorrhagic stroke incidence or recurrence was studied in women and men using Cox proportional hazard models and Poisson regression models. Women-to-men relative hazard ratios (RHR) and rate differences (RD) were estimated for each risk factor. Left-truncated age was used as timescale.

RESULTS

The age-adjusted stroke incidence rate was lower in women than men (3.9 vs 4.4 per 1000 person-years), as was the age-adjusted stroke recurrence rate (10.0 vs 11.7). Hypertension and smoking were associated with stroke risk in both sexes. HDL cholesterol was associated with lower stroke incidence in women but not in men (RHR 0.49; CI 0.27-0.88; and RD 1.39; CI - 1.31 to 4.10). Overweight was associated with a lower stroke recurrence in women but not in men (RHR 0.42; CI 0.23-0.80; and RD 9.05; CI 2.78-15.32).

CONCLUSIONS

In high-risk population, sex modifies the association of HDL cholesterol on stroke incidence, and the association of overweight on stroke recurrence. Our findings highlight the importance of sex-specific secondary prevention.

The effect of body mass index on stroke prognosis: A systematic review and meta-analysis of 32 cohort studies with 330,353 patients

BACKGROUND

Many studies have explored the impact of body mass index (BMI) on stroke prognosis, yet findings remain inconsistent.

AIMS

The aims of this study were to conduct a systematic review and meta-analyses to summarize the existing evidence on BMI and stroke outcomes.

METHODS

PubMed, Web of Science, Embase, The Cochrane Library, CNKI, CBM, Wanfang Database, and VIP Database were systematically searched from inception to 1 January 2023. Cohort studies were included if they reported on a population of patients with stroke, evaluated BMI on stroke outcomes (mortality/recurrence/score of modified Rankin scale (mRs)), and reported original data. Data extraction and quality assessment were independently undertaken by two reviewers. Stata 16.0 software was used for meta-analysis.

RESULTS

Thirty-two studies involving 330,353 patients (5 Chinese language articles) were included in the analysis. The proportion of underweight, overweight, and obese patients was 1.85%, 18.2%, and 15.6%, respectively. Compared with normal weight, being underweight was associated with an increased risk of mortality (relative risk (RR) = 1.78, 95% confidence interval (CI) = 1.60-1.96), poor functional outcomes defined as modified Rankin scale ⩾ 3 (RR = 1.33, 95% CI = 1.22-1.45), and stroke recurrence (RR = 1.19, 95% CI = 1.04-1.37). Being overweight but not obese was associated with reduced mortality (RR = 0.81, 95% CI = 0.74-0.89) and better functional outcomes (RR = 0.92, 95% CI = 0.89-0.96), but did not alter the risk of stroke recurrence (RR = 1.03, 95% CI = 0.90-1.17). Obesity was associated with lower risk of mortality (RR = 0.76, 95% CI = 0.72-0.81) and better functional outcomes (RR = 0.89, 95% CI = 0.84-0.94).

CONCLUSIONS

Our findings indicate that in patients with stroke, being underweight is associated with an increased risk of mortality, poor functional outcomes, and stroke recurrence. In contrast, being overweight but not obese, or being obese, was associated with a decreased risk of mortality and better functional outcomes. This is consistent with the obesity paradox in stroke, whereby obesity increases stroke risk in the general population but is associated with improved outcome in patients suffering stroke.

Dyslipidemia versus obesity as predictors of ischemic stroke prognosis: a multi-center study in China

BACKGROUND

This multicenter observational study aimed to determine whether dyslipidemia or obesity contributes more significantly to unfavorable clinical outcomes in patients experiencing a first-ever ischemic stroke (IS).

METHODS

The study employed a machine learning predictive model to investigate associations among body mass index (BMI), body fat percentage (BFP), high-density lipoprotein (HDL), triglycerides (TG), and total cholesterol (TC) with adverse outcomes in IS patients. Extensive real-world clinical data was utilized, and risk factors significantly linked to adverse outcomes were identified through multivariate analysis, propensity score matching (PSM), and regression discontinuity design (RDD) techniques. Furthermore, these findings were validated via a nationwide multicenter prospective cohort study.

RESULTS

In the derived cohort, a total of 45,162 patients diagnosed with IS were assessed, with 522 experiencing adverse outcomes. A multifactorial analysis incorporating PSM and RDD methods identified TG (adjusted odds ratio (OR) = 1.110; 95% confidence interval (CI): 1.041-1.183; P <  0.01) and TC (adjusted OR = 1.139; 95%CI: 1.039-1.248; P <  0.01) as risk factors. However, BMI, BFP, and HDL showed no significant effect. In the validation cohort, 1410 controls and 941 patients were enrolled, confirming that lipid levels are more strongly correlated with the prognosis of IS patients compared to obesity (TC, OR = 1.369; 95%CI: 1.069-1.754; P <  0.05; TG, OR = 1.332; 95%CI: 1.097-1.618; P <  0.01).

CONCLUSION

This study suggests that dyslipidemia has a more substantial impact on the prognosis of IS patients compared to obesity. This highlights the importance of prioritizing dyslipidemia management in the treatment and prevention of adverse outcomes in IS patients.

Effects of body mass index on the immune response within the first days after major stroke in humans

INTRODUCTION

Immunological alterations associated with increased susceptibility to infection are an essential aspect of stroke pathophysiology. Several immunological functions of adipose tissue are altered by obesity and are accompanied by chronic immune activation. The purpose of this study was to examine immune function (monocytes, granulocytes, cytokines) as a function of body mass index (BMI: 1st group: 25; 2nd group: 25 BMI 30; 3rd group: 30) and changes in body weight post stroke.

METHOD

Fat status was assessed using standardized weight measurements on days 1, 2, 3, 4, 5, and 7 after ischemic stroke in a cohort of 40 stroke patients and 16 control patients. Liver fat and visceral fat were assessed by MRI on day 1 or 2 [I] and on day 5 or 7 [II]. Leukocyte subpopulations in peripheral blood, cytokines, chemokines, and adipokine concentrations in sera were quantified. In a second cohort (stroke and control group, n = 17), multiple regression analysis was used to identify correlations between BMI and monocyte and granulocyte subpopulations.

RESULTS

Weight and fat loss occurred from the day of admission to day 1 after stroke without further reduction in the postischemic course. No significant changes in liver or visceral fat were observed between MRI I and MRI II. BMI was inversely associated with IL-6 levels, while proinflammatory cytokines such as eotaxin, IFN-β, IFN -γ and TNF-α were upregulated when BMI increased. The numbers of anti-inflammatory CD14+CD16+ monocytes and CD16+CD62L- granulocytes were reduced in patients with higher BMI values, while that of proinflammatory CD16dimCD62L+ granulocytes was increased.

CONCLUSION

A small weight loss in stroke patients was detectable. The data demonstrate a positive correlation between BMI and a proinflammatory poststroke immune response. This provides a potential link to how obesity may affect the clinical outcome of stroke patients.

Blood pressure reduction cut-points for orthostatic hypotension in stroke survivors using a sit-up test: a multicentre cross-sectional study

OBJECTIVE

The sit-up test is used to assess orthostatic hypotension in stroke survivors who cannot stand independently without using a tilt table. However, no study has identified the optimal cut-points for orthostatic hypotension using the test. Therefore, this study aimed to examine the decrease in SBP and DBP during the sit-up test to detect orthostatic hypotension in individuals with stroke.

METHODS

Thirty-eight individuals with stroke, recruited from three convalescent rehabilitation hospitals, underwent the sit-up and head-up tilt tests. Systolic and diastolic orthostatic hypotension was defined as a decrease of at least 20 and 10 mmHg in the SBP and DBP, respectively, during the head-up tilt test. The receiver operator characteristic curve with the Youden Index was used to identify the optimal cut-points.

RESULTS

Eight and three participants showed systolic and diastolic orthostatic hypotension, respectively. The optimal cut-points for orthostatic hypotension using the sit-up test were a decrease of 10 mmHg in SBP [sensitivity = 87.5% (95% confidence interval: 47.4-99.7), specificity = 96.7% (82.8-99.9)] and 5 mmHg in DBP [sensitivity = 100.0% (29.2-100.0), specificity = 88.6% (73.3-96.8)].

CONCLUSION

Compared with the conventional cut-points, smaller cut-points of a decrease in SBP and DBP may be better to identify orthostatic hypotension in individuals with stroke using the sit-up test. The findings of this study may provide valuable information for the clinical application of the sit-up test.

The relationship between nutritional status at the time of stroke on adverse outcomes: a systematic review and meta-analysis of prospective cohort studies

CONTEXT AND OBJECTIVE

The impact of existing malnutrition on stroke outcomes is poorly recognised and treated. Evidence was systematically reviewed and quantified by meta-analysis.

METHODS

MEDLINE, EMBASE and Web of Science were searched from inception to 11 January 2021 and updated in July. Prospective cohort studies, in English, evaluating anthropometric and biomarkers of nutrition on stroke outcomes were included. Risk of bias was assessed using the Scottish Intercollegiate Guidelines Network checklist.

RESULTS

Twenty-six studies (n = 156 249) were eligible (follow-up: One month-14 years). Underweight patients had increased risk of long-term mortality (adjusted hazard ratio = 1.65,1.41-1.95), whilst overweight (0.80,0.74-0.86) and obese patients (0.80,0.75-0.85) had decreased risk compared to normal weight. Odds of mortality decreased in those with high serum albumin (odds ratio = 0.29,0.18-0.48) and increased with low serum albumin (odds ratio = 3.46,1.78-6.74) compared to normal serum albumin (30-35 g/L). Being malnourished compared to well-nourished, as assessed by the Subjective Global Assessment (SGA) or by a combination of anthropometric and biochemical markers increased all-cause mortality (odds ratio = 2.38,1.85-3.06) and poor functional status (adjusted odds ratio = 2.21,1.40-3.49).

CONCLUSION

Nutritional status at the time of stroke predicts adverse stroke outcomes.

Higher BMI Confers a Long-Term Functional Status Advantage in Elderly New Zealand European Stroke Patients

OBJECTIVE

Obesity is a risk factor for ischaemic stroke but provides a survival advantage. The relationship between body mass index (BMI) and long-term function is less clear. The presence of an obesity paradox can inform clinical care and identify vulnerable patients who need additional support post-stroke.

MATERIALS AND METHODS

This study used linked health administrative data of a population based cohort of adult patients who experienced an ischaemic stroke between 2012 and 2017 in New Zealand. Patient demographics were obtained from the National Minimum Dataset (NMDS). BMI and Activities of Daily Living scores (ADLs) for the same patients were obtained from the International Resident Assessment Instrument (InterRAI™).

RESULTS

Linked data was obtained for 3731 patients. Ninety-five percent of the cohort were aged 65 or older and the average age of stroke was 84.5 years. The majority of patients (55%) identified as New Zealand European. Beta regression indicated BMI and European ethnicity were negatively associated with ADL score. Univariate analysis confirmed patients with underweight stroke had significantly higher ADL scores than other BMI categories (p<0.001), however functional status for patients with overweight and obesity were comparable. Further, Asian and Pacific Peoples had higher ADL scores than Europeans (p<0.05). A higher BMI was advantageous to all ADL subscores.

CONCLUSION

An abridged obesity paradox was evident in our cohort of stroke patients where a BMI in the overweight, but not obese range conferred a long-term functional status advantage. Collectively these results suggest underweight and non-European patients may require additional supportive clinical care post-stroke.

Obesity paradox and stroke: a narrative review

BACKGROUND

Despite obesity is an established risk factor for stroke, several studies reported a better outcome after stroke in obese and overweight patients. This counterintuitive finding, which was described in the whole spectrum of cardiovascular diseases, is known as obesity paradox.

OBJECTIVE

This is a narrative overview on the obesity paradox and stroke.

METHODS

We used as sources MEDLINE/PubMed, CINAHL, EMBASE, and Cochrane Library from inception to 2019, and selected papers that discussed the association of obesity with outcome and mortality after stroke.

RESULTS

The majority of studies reported lower mortality rates and better functional outcome after stroke in obese and overweight patients compared with normal weight and underweight patients, suggesting the existence of an obesity paradox in stroke. However, available studies are limited by several major methodological concerns including absence of randomized trials, retrospective nature of most studies, assessment of obesity with body mass index (BMI), non-linear relationship between BMI and outcome, short follow-up period, and differences in co-morbid conditions and stroke characteristics.

CONCLUSIONS

The existence of an obesity paradox in stroke is still controversial and further higher quality evidence is needed to clarify the relationship between obesity and stroke outcome.

LEVEL OF EVIDENCE

Level V, narrative review.

Adiposity and Outcome After Ischemic Stroke: Obesity Paradox for Mortality and Obesity Parabola for Favorable Functional Outcomes

BACKGROUND AND PURPOSE

A survival advantage among individuals with higher body mass index (BMI) has been observed for diverse acute illnesses, including stroke, and termed the obesity paradox. However, prior ischemic stroke studies have generally tested only for linear rather than nonlinear relations between body mass and outcome, and few studies have investigated poststroke functional outcomes in addition to mortality.

METHODS

We analyzed consecutive patients with acute ischemic stroke enrolled in a 60-center acute treatment trial, the NIH FAST-MAG acute stroke trial. Outcomes at 3 months analyzed were (1) death; (2) disability or death (modified Rankin Scale score, 2-6); and (3) low stroke-related quality of life (Stroke Impact Scale<median). Relations with BMI were analyzed univariately and in multivariate models adjusting for 14 additional prognostic variables.

RESULTS

Among 1033 patients with acute ischemic stroke, average age was 71 years (±13), 45.1% female, National Institutes of Health Stroke Scale 10.6 (±8.3), and BMI 27.5 (±5.6). In both unadjusted and adjusted analysis, increasing BMI was linearly associated with improved 3-month survival (P=0.01) odds ratios in adjusted analysis for mortality declined across the BMI categories of underweight (odds ratio, 1.7 [CI, 0.6-4.9]), normal (odds ratio, 1), overweight (0.9 [CI, 0.5-1.4]), obese (0.5, [CI, 0.3-1.0]), and severely obese (0.4 [CI, 0.2-0.9]). In unadjusted analysis, increasing BMI showed a U-shaped relation to poststroke disability or death (modified Rankin Scale score, 2-6), with odds ratios of modified Rankin Scale score, 2 to 6 for underweight, overweight, and obese declined initially when compared with normal weight patients, but then increased again in severely obese patients, suggesting a U-shaped or J-shaped relation. After adjustment, including for baseline National Institutes of Health Stroke Scale, modified Rankin Scale score 2 to 6 was no longer related to adiposity.

CONCLUSIONS

Mortality and functional outcomes after acute ischemic stroke have disparate relations with patients' adiposity. Higher BMI is linearly associated with increased survival; and BMI has a U-shaped or J-shaped relation to disability and stroke-related quality of life. Potential mechanisms including nutritional reserve aiding survival during recovery and greater frequency of atherosclerotic than thromboembolic infarcts in individuals with higher BMI.

Factors Associated with Changes in Functional Independence after Six Months of Ischemic Stroke

The aim of this study is to investigate the changes in functional independence and their associated factors during the first 6 months to 1 year after stroke onset. This study is the interim results of the Korean Stroke Cohort for Functioning and Rehabilitation. A total of 1,011 participants were included and classified into 3 subgroups according to changes in the Korean version of Modified Barthel Index (K-MBI) scores that occurred between 6 months to 1 year after stroke onset: the improved group (IG), with scores that increased 5 points or more; the stationary group (SG), with the K-MBI score changes ranging from -4 to +4 points; and the declined group (DG), with the K-MBI scores that decreased 5 points or more. Ordinal logistic regression analyses were used to assess the factors influencing changes in the K-MBI score. Among 1,011 patient, 436 patients (43.1%), 398 patients (39.4%) and 117 patients (17.5%) were classified into the IG, SG, and DG, respectively. Obesity and Geriatric Depression Scale score were significant influencing factors for changes in the K-MBI scores. Obesity showed a positive influence on the K-MBI score, while depression showed a negative influence.

Association between body mass index and stroke severity in acute ischaemic stroke with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

The objective of this study was to investigate the association between body mass index (BMI) and both initial stroke severity at presentation and functional outcomes after acute ischaemic stroke (AIS) in patients with non-valvular atrial fibrillation (NVAF).

METHODS

Patients were categorized on the basis of their BMI into underweight (BMI <18.5, n = 111), normal (18.5 ≤ BMI <25, n = 1036) and overweight to obese (BMI ≥25, n = 472) groups. Initial stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) score and functional outcomes were assessed using the modified Rankin Scale score at discharge. The differences in stroke severity and functional outcomes were compared between groups using robust log-linear regression with a Poisson distribution and binary logistic regression analysis.

RESULTS

A total of 1619 AIS patients with NVAF from six hospitals were included. Compared with the NIHSS scores [median 5, interquartile range (IQR) 2-14] of normal-weight patients, the NIHSS scores (median 9, IQR 4-19) of underweight patients were more likely to be higher, whereas those of overweight to obese patients were lower (median 4, IQR 1-12) (P < 0.001). In terms of functional outcomes after stroke, underweight patients had a higher risk of poor functional outcomes (odds ratio 1.78, 95% confidence interval 1.09-2.56, P = 0.01) but overweight to obese patients had no significant difference in functional outcomes compared with normal-weight patients.

CONCLUSION

An inverse association was found between BMI and stroke severity in AIS patients with NVAF. This suggests the presence of an obesity paradox for short-term outcomes in patients with NVAF.

Increased Body Mass Index Associated With Reduced Risk of Delayed Cerebral Ischemia and Subsequent Infarction After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Increased body mass index (BMI) may be protective against cerebral ischemia in certain clinical contexts.

OBJECTIVE

To investigate whether increased BMI was associated with delayed cerebral ischemia (DCI) and subsequent infarction after aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

We retrospectively reviewed the clinical course of patients presenting to our institution for management of aSAH. Patient were segregated according to BMI< or ≥29.4, a value determined by Classification and Regression Tree analysis. Predictors of DCI and delayed infarction were identified using stepwise multivariate logistic regression analysis.

RESULTS

There were 161 patients included for analysis. Average BMI within our patient cohort was 28.9, with 67 patients presenting with a BMI of ≥29.4 on admission. DCI occurred in 50 patients (31.1%) and was complicated by delayed infarction in 15 patients (9.3%). On stepwise multivariate analysis, BMI ≥ 29.4 was independently associated with reduced likelihood of DCI (odds ratio [OR] 0.42, 95% confidence interval [CI] 0.18-0.92) and delayed infarction (OR 0.13, 95% CI 0.02-0.61; P = .008). Increasing maximum flow velocity on transcranial Doppler ultrasound was independently associated with increased odds of both DCI (Unit OR 1.19, 95% CI 1.09-1.30; P < .001) and delayed infarction (Unit OR 1.31, 95% CI 1.13-1.56; P < .001), while intracerebral hemorrhage was independently associated with increased odds of delayed infarction (OR 6.99, 95% CI 1.82-30.25; P = .005).

CONCLUSION

We report an association between elevated BMI and reduced incidence of DCI and delayed infarction, suggesting a protective effect of increasing BMI on the risk of ischemic complications after aSAH.

Does the obesity paradox predict functional outcome in intracerebral hemorrhage?

OBJECTIVEBeing overweight or mildly obese has been associated with a decreased risk of death or hospitalization in patients with cardiovascular disease. Similarly, overweight patients admitted to an intensive care unit (ICU) have improved survival up to 1 year after admission. These counterintuitive observations are examples of the "obesity paradox." Does the obesity paradox exist in patients with intracerebral hemorrhage (ICH)? In this study the authors examined whether there was an association between obesity and functional outcome in patients with ICH.METHODSThe authors analyzed 202 patients admitted to the neurological ICU (NICU) who were prospectively enrolled in the Columbia University ICH Outcomes Project between September 2009 and December 2012. Patients were categorized into 2 groups: overweight (body mass index [BMI] ≥ 25 kg/m2) and not overweight (BMI < 25 kg/m2). The primary outcome was defined as survival with favorable outcome (modified Rankin Scale [mRS] score 0-3) versus death or severe disability (mRS score 4-6) at 3 months.RESULTSThe mean age of the patients in the study was 61 years. The mean BMI was 28 ± 6 kg/m2. The mean Glasgow Coma Scale score was 10 ± 4 and the mean ICH score was 1.9 ± 1.3. The overall 90-day mortality rate was 41%. Among patients with a BMI < 25 kg/m2, 24% (17/70) had a good outcome, compared with 39% (52/132) among those with a BMI ≥ 25 kg/m2 (p = 0.03). After adjusting for ICH score, sex, do-not-resuscitate code status, and history of hypertension, being overweight or obese (BMI ≥ 25 kg/m2) was associated with twice the odds of having a good outcome compared with patients with BMI < 25 kg/m2 (adjusted odds ratio 2.05, 95% confidence interval 1.03-4.06, p = 0.04).CONCLUSIONSIn patients with ICH admitted to the NICU, being overweight or obese (BMI ≥ 25 kg/m2) was associated with favorable outcome after adjustment for established predictors. The reason for this finding requires further study.

Body mass index and clinical outcomes in patients after ischaemic stroke in South Korea: a retrospective cohort study

OBJECTIVES

Although obesity is a risk factor for stroke, its impact on mortality in patients with stroke remains unclear. In this study, we aimed to evaluate the relationship between body mass index (BMI) and mortality due to ischaemic stroke among adults aged 20 years and above in Korea.

DESIGN

Retrospective cohort study.

SETTING

A tertiary-hospital-based stroke registry linked to the death records.

PARTICIPANTS

3599 patients admitted for ischaemic stroke from January 2007 to June 2013.

OUTCOME MEASURES

The HRs for all-cause and stroke-related mortality were calculated using Cox proportional hazards models. Progression from stroke-related mortality was assessed using the Fine-Grey competing risk model, treating other-cause mortality as a competing risk. Adjustments were made for age, gender, smoking status, Charlson comorbidity index, cardiovascular or non-cardiovascular comorbidities, stroke severity, severity related to other medical conditions, complications and enrolment year. We repeated the analysis with stratification based on age groups (less than 65 vs 65 years and above).

RESULTS

For stroke-related mortality, there was no significant difference among the four BMI groups. The risk of all-cause mortality was 36% higher in the underweight group than in the normal weight group (long-term HR=1.36, 95% CI: 1.04 to 1.79), whereas the mortality risk of the obese group was significantly lower (HR=0.66, 95% CI: 0.54 to 0.81). Although this relationship was not estimated in the younger group, it was found that obesity had a protective effect on the all-cause mortality in the elderly (long-term HR=0.66, 95% CI: 0.52 to 0.83).

CONCLUSIONS

Obesity is more likely to reduce mortality risk than normal weight, especially in elderly patients.

Evaluating the Effect of Comprehensive Intervention on Cerebro-Vascular Function in Population at High Risk of Stroke

BACKGROUND

Today there exists few intervention researches on cerebro-vascular function in populations at high risk of stroke in China.

METHODS

Patients more than 40 years old, with at least 1 of stroke risk factors were recruited from outpatient department in 3 hospitals. A quasi-experimental design was performed by assigning participants into 3 groups: comprehensive intervention group, health education group, and control group. Participants in the control group received no intervention but were informed of risk factors of stroke. For health education group, a health education class was performed. Except to the health education program, participants in the comprehensive intervention group received an additional health life and behavior guidance.

RESULTS

After the intervention, the Cerebro-Vascular Function Scores (CVFS) had significant differences among 3 groups (F = 5.252, P < 0.05). There was a significant increase in CVFS compared to the control group (P = 0.003, 95%CI: 1.552-8.493). Significantly changes in obesity were observed in comprehensive intervention group before and after the intervention (χ² = 9.0747, P = 0.0026). The results of logistic regression showed that comprehensive intervention group had a significant decrease in prevalence of obesity (OR = 0.482, 95% CI: 0.242-0.961) compared to the control group.

CONCLUSION

Health education on stroke in a high-risk population combined with guidance on proper health life and behavior can be effective in preventing stroke.

Association Between Body Mass Index and Results of Rehabilitation in Patients After Stroke: A 3-Month Observational Follow-Up Study

Background

We assessed the relationship between body mass index and results of rehabilitation in stroke patients.

Material/Methods

The study was carried out at the Clinical Rehabilitation Ward with Early Neurological Rehabilitation Unit at the Clinical Hospital. The examinations were performed 3 times. Based on inclusion and exclusion criteria, 128 subjects were qualified for the first examination, the second examination involved 114 subjects, and 100 stroke patients participated in the third examination. Body mass was examined with an accuracy of 0.1 kg, using a Tanita MC–780 MA body composition analyser. Body mass index (BMI) was calculated for all of the subjects. Effects of rehabilitation were assessed with the Barthel index and Ashworth scale.

Results

Higher functional status in daily life, measured with the Barthel scale, was found in patients with normal body mass, compared to the overweight and obese subjects (examination I, II, and II). Exam I showed that before rehabilitation the overweight patients obtained significantly higher results in assessment of upper limbs, based on the Ashworth scale (mean=0.35±0.54) compared to the obese patients (mean=0.03±0.32) and those with normal body weight (mean=0.24±0.75).

Conclusions

Following hospital-based rehabilitation, patients with normal body mass achieved greater functional efficiency. The findings also show a trend towards normalization of BMI. The positive effect of rehabilitation was sustained for 3 months (Exam III), which may contribute to decreased risk of cardiovascular diseases and complications such as stroke.

Survival After Ischemic and Hemorrhagic Stroke: A 4-Year Follow-Up at a Mexican Hospital

BACKGROUND

Overall, 75.2% of deaths from stroke occur in low- and middle-income countries. Mexico is a middle-income country with little information about the prognosis of early and late postischemic and hemorrhagic stroke.

OBJECTIVE

To evaluate the factors associated with post-stroke survival in the Mexican population.

METHODS

Observational study of consecutive stroke cases involving a first-ever hemorrhagic or ischemic stroke, with patients who received care at the National Institute of Neurology and Neurosurgery, in Mexico City, between 2009 and 2012. Patients were followed for up to 4 years after the index event. Exploratory analysis of survival was carried out with Kaplan-Meier and log-rank tests. Factors associated with survival time were determined using Cox models.

RESULTS

A total of 300 out of 544 (55.15%) patients had a hemorrhagic stroke, 135 of 544 (24.82%) patients died during the entire follow-up period, and 56 of 544 (10.29%) died in the first 30 days post-stroke (early mortality). Early mortality after stroke was associated with age ≥ 65 years (Adjusted Hazard Ratio - AHR = 2.07, P = .02) and ≥ 2 in-hospital medical complications (AHR = 46.13, P < .01). Late mortality was associated with age ≥ 65 years (AHR = 3.43, P < .01), ≥2 in-hospital medical complications (AHR = 2.55, P < .01), high comorbidity (AHR = 5.43, P < .01), and recurrence (AHR = 1.90, P = .01).

CONCLUSIONS

Patients with hemorrhagic and ischemic stroke who presented in-hospital medical complications, high comorbidity, and were over 65 years old had higher rates of early and late mortality.

Body Mass Index and Clinical Outcomes in Large Vessel Occlusion Acute Ischemic Stroke after Endovascular Therapy

Background and Purpose

Several reports have described lower mortality rates in overweight or obese patients as compared to normal weight ones. In the past decade, several studies have investigated the phenomenon, commonly known as the obesity paradox, with mixed results thus far. We sought to determine whether outcomes differ between patients with large vessel occlusion strokes (LVOS) after endovascular therapy (ET) according to their body mass index (BMI).

Methods

We reviewed our prospectively collected endovascular database at a tertiary care academic institution. All patients that underwent ET for acute LVOS were categorized according to their BMI into 4 groups: (1) underweight (BMI < 18.5), (2) normal weight (BMI = 18.5-25), (3) overweight (BMI = 25-30), and (4) obese (BMI > 30). Baseline characteristics, procedural radiological as well as outcome parameters where compared.

Results

A total of 926 patients qualified for the study, of which 20 (2.2%) were underweight, 253 (27.3%) had a normal weight, 315 (34%) were overweight, and 338 (36.5%) were obese. When compared with normal weight (reference), overweight patients were younger, had higher rates of dyslipidemia and diabetes and higher glucose levels, while obese patients were younger, less often smokers, and had higher rates of hypertension and diabetes and higher glucose levels. Other baseline and procedural characteristics were comparable. The rates of successful reperfusion (modified treatment in cerebral ischemia, 2b-3), parenchymal hematomas, 90-day good clinical outcomes (modified Rankin scale, 0-2), and 90-day mortality were comparable between groups. On multivariate analysis, BMI was not associated with good outcomes nor mortality.

Conclusion

In patients treated with mechanical thrombectomy, BMI is not associated with outcomes. However, patients who are overweight or obese have more comorbidities and a higher stroke risk and, thus, should strive for a normal weight.

Metabolic syndrome identifies normal weight insulin-resistant stroke patients at risk for recurrent vascular disease

BACKGROUND

The obesity paradox refers to the finding in observational studies that patients with obesity have a better prognosis after stroke than normal weight patients.

AIM

To test the hypothesis that there might be important heterogeneity within the obese stroke population, such that those with metabolic syndrome would be at higher risk for stroke or myocardial infarction and all-cause mortality compared to patients without metabolic syndrome.

METHODS

The Insulin Resistance Intervention after Stroke trial enrolled non-diabetic patients with a recent ischemic stroke or transient ischemic attack and insulin resistance. We examined the association between metabolic syndrome and outcome risk in patients with normal weight at entry (body mass index (BMI) = 18.5-24.9 kg/m²), overweight (BMI = 25-29.9 kg/m²), or obesity (BMI ≥ 30 kg/m²). Analyses were adjusted for demographic features, treatment assignment, smoking, and major comorbid conditions.

RESULTS

Metabolic syndrome was not associated with greater risk for stroke or myocardial infarction among 1536 patients who were overweight (adjusted hazard ratio (HR), 0.95; 95% confidence interval (CI): 0.69-1.31) or 1626 obese patients (adjusted HR, 1.00; 95% CI: 0.70-1.41). However, among 567 patients with a normal BMI, metabolic syndrome was associated with increased risk for stroke or myocardial infarction (adjusted HR, 2.05; 95% CI: 1.25-3.37), and all-cause mortality (adjusted HR, 1.70; 95% CI: 1.03-2.81) compared to patients without metabolic syndrome.

CONCLUSIONS

The presence of metabolic syndrome identified normal weight patients with insulin resistance but no diabetes who have a higher risk of adverse cardiovascular outcomes, compared with patients without metabolic syndrome.

Racial differences in intracerebral haemorrhage outcomes in patients with obesity

OBJECTIVE

This study was conducted to determine the role of obesity and race in intracerebral haemorrhage (ICH) outcomes.

METHODS

The Get with the guideline-Stroke database was queried for all admitted patients with spontaneous ICH. Secondary causes of ICH were excluded. Body mass index (BMI) was classified using the Center for Disease Control guidelines. Race was classified as White or non-White. Demographics, clinical, imaging data were retrieved. Outcome measures were hematoma expansion at 24 h and discharge disposition.

RESULTS

A total of 428 patients were included in our analysis. Female gender, past history of congestive heart failure, diabetes mellitus, HbA1c, blood pressure, ICH volume, ICH location, intraventricular haemorrhage and hospital length of stay deferred across BMI categories. On multivariate analysis, along with obese categories, age, ICH location and ICH volume were independent predictors of poor outcomes (hematoma expansion and poor discharge disposition). After adjusting for these variables, obesity remained a predictor of poor disposition outcome compared with normal and overweight subjects; Normal vs. Obese OR 0.26 CI 0.115-0.593 p = 0.0014; Obese vs. Overweight OR 3.79 CI 1.68-8.52 p = 0.0013. Nonetheless, obesity did not influence hematoma expansion. Overall, BMI-race classification did not influence outcomes. However, among non-Whites, the obese category had higher odds of a poor disposition outcome than normal (OR 6.84 CI 2.12-22.22 p = 0.0013) or overweight (OR 8.45 CI 2.6-27.49 p = 0.0004) categories.

CONCLUSION

An obesity paradox in ICH was not observed in our cohort. In the non-White population, patients with obesity were likely to be associated with poor disposition outcome. Similar findings were not observed in White population.

Effect of body mass index on outcome after aneurysmal subarachnoid hemorrhage treated with clipping versus coiling

OBJECTIVE It has been suggested that increased body mass index (BMI) may confer a protective effect on patients who suffer from aneurysmal subarachnoid hemorrhage (aSAH). Whether the modality of aneurysm occlusion influences the effect of BMI on patient outcomes is not well understood. The authors aimed to compare the effect of BMI on outcomes for patients with aSAH treated with surgical clipping versus endovascular coiling. METHODS The authors retrospectively reviewed the outcomes for patients admitted to their institution for the management of aSAH treated with either clipping or coiling. BMI at the time of admission was recorded and used to assign patients to a group according to low or high BMI. Cutoff values for BMI were determined by classification and regression tree analysis. Predictors of poor functional outcome (defined as modified Rankin Scale score > 2 measured ≥ 90 days after the ictus) and posttreatment cerebral hypodensities detected during admission were then determined separately for patients treated with clipping or coiling using stepwise multivariate logistic regression analysis. RESULTS Of the 469 patients admitted to the authors' institution with aSAH who met the study's inclusion criteria, 144 were treated with clipping and 325 were treated with coiling. In the clipping group, the frequency of poor functional outcome was higher in patients with BMI ≥ 32.3 kg/m² (47.6% vs 19.0%; p = 0.007). In contrast, in the coiling group, patients with BMI ≥ 32.3 kg/m² had a lower frequency of poor functional outcome at ≥ 90 days (5.8% vs 30.9%; p < 0.001). On multivariate analysis, high BMI was independently associated with an increased (OR 3.92, 95% CI 1.20-13.41; p = 0.024) and decreased (OR 0.13, 95% CI 0.03-0.40; p < 0.001) likelihood of poor functional outcome for patients treated with clipping and coiling, respectively. For patients in the surgical group, BMI ≥ 28.4 kg/m² was independently associated with incidence of cerebral hypodensities during admission (OR 2.44, 95% CI 1.16-5.25; p = 0.018) on multivariate analysis. For patients treated with coiling, BMI ≥ 33.2 kg/m² was independently associated with reduced odds of hypodensities (OR 0.45, 95% CI 0.21-0.89; p = 0.021). CONCLUSIONS The results of this study suggest that BMI may differentially affect functional outcomes after aSAH, depending on treatment modality. These findings may aid in treatment selection for patients with aSAH.

Obesity paradox in stroke - Myth or reality? A systematic review

Background and purpose

Both stroke and obesity show an increasing incidence worldwide. While obesity is an established risk factor for stroke, its influence on outcome in ischemic stroke is less clear. Many studies suggest a better prognosis in obese patients after stroke (“obesity paradox”). This review aims at assessing the clinical outcomes of obese patients after stroke by performing a systematic literature search.

Methods

The reviewers searched MEDLINE from inception to December 2015. Studies were eligible if they included outcome comparisons in stroke patients with allocation to body weight.

Results

Twenty-five studies (299’750 patients) were included and none was randomised. Ten of 12 studies (162’921 patients) reported significantly less mortality rates in stroke patients with higher BMI values. Seven of 9 studies (92’718 patients) ascertained a favorable effect of excess body weight on non-fatal outcomes (good clinical outcome, recurrence of vascular events). Six studies (85’042 patients) indicated contradictory results after intravenous thrombolysis (IVT), however. Several methodological limitations were observed in major part of studies (observational study design, inaccuracy of BMI in reflecting obesity, lacking body weight measurement, selection bias, survival bias).

Conclusion

Most observational data indicate a survival benefit of obese patients after stroke, but a number of methodological concerns exist. No obesity paradox was observed in patients after IVT. There is a need for well-designed randomized controlled trials assessing the effects of weight reduction on stroke risk in obese patients.

Assessment of triglyceride and cholesterol in overweight people based on multiple linear regression and artificial intelligence model

Background

The prevalence of high hyperlipemia is increasing around the world. Our aims are to analyze the relationship of triglyceride (TG) and cholesterol (TC) with indexes of liver function and kidney function, and to develop a prediction model of TG, TC in overweight people.

Methods

A total of 302 adult healthy subjects and 273 overweight subjects were enrolled in this study. The levels of fasting indexes of TG (fs-TG), TC (fs-TC), blood glucose, liver function, and kidney function were measured and analyzed by correlation analysis and multiple linear regression (MRL). The back propagation artificial neural network (BP-ANN) was applied to develop prediction models of fs-TG and fs-TC.

Results

The results showed there was significant difference in biochemical indexes between healthy people and overweight people. The correlation analysis showed fs-TG was related to weight, height, blood glucose, and indexes of liver and kidney function; while fs-TC was correlated with age, indexes of liver function (P < 0.01). The MRL analysis indicated regression equations of fs-TG and fs-TC both had statistic significant (P < 0.01) when included independent indexes. The BP-ANN model of fs-TG reached training goal at 59 epoch, while fs-TC model achieved high prediction accuracy after training 1000 epoch.

Conclusions

In conclusions, there was high relationship of fs-TG and fs-TC with weight, height, age, blood glucose, indexes of liver function and kidney function. Based on related variables, the indexes of fs-TG and fs-TC can be predicted by BP-ANN models in overweight people.

Electronic supplementary material

The online version of this article (doi:10.1186/s12944-017-0434-5) contains supplementary material, which is available to authorized users.

Neuroinflammation and comorbidities are frequently ignored factors in CNS pathology

Virtually all drug interventions that have been successful pre-clinically in experimental stroke have failed to prove their efficacy in a clinical setting. This could be partly explained by the complexity and heterogeneity of human diseases as well as the associated co-morbidities which may render neuroprotective drugs less efficacious in clinical practice. One aspect of crucial importance in the physiopathology of stroke which is not completely understood is neuroinflammation. At the present time, it is becoming evident that subtle, but continuous neuroinflammation can provide the ground for disorders such as cerebral small vessel disease. Moreover, advanced aging and a number of highly prevalent risk factors such as obesity, hypertension, diabetes and atherosclerosis could act as "silent contributors" promoting a chronic proinflammatory state. This could aggravate the outcome of various pathological entities and can contribute to a number of subsequent post-stroke complications such as dementia, depression and neurodegeneration creating a pathological vicious cycle. Moreover, recent data suggests that the inflammatory process might be closely linked with multiple neurodegenerative pathways related to depression. In addition, pro-inflammatory cytokines could play a central role in the pathophysiology of both depression and dementia.

The obesity paradox in stroke: impact on mortality and short-term readmission

BACKGROUND

The aim of the present study was to assess the association of obesity with the mortality of hospitalized patients with acute stroke and the risk of readmission in less than 30 days.

METHODS

A retrospective chart review of a cohort of consecutive patients admitted with stroke as the primary reason for discharge in Spain between January 1, 2005, and December 31, 2011, was performed. Patients with a diagnosis of obesity were identified. The mortality and readmittance indexes of obese patients were compared against the subpopulation without theses diagnosis.

RESULTS

A total of 201,272 stroke admittances were analyzed, and 14,047 (7.0%) diagnosis of obesity were identified. In-hospital global mortality reached 14.9%, and readmittance risk was 5.9%. Obese patients showed a lower in-hospital mortality risk (odds ratio [OR], .71; 95% confidence interval [CI], .67-.76) and early readmittance risk (OR, .89; 95% CI, .82-.96) than the nonobese even after adjusting for possible confounding factors.

CONCLUSIONS

Obesity in those hospitalized for stroke is associated with reduced in-hospital mortality risk and early readmittance.

Body mass index in dementia

This review comprehensively examines the current knowledge on the relationship between body mass index (BMI) and dementia. The association between BMI and cognition is complex: in younger adults, higher BMIs are associated with impaired cognition. Overweight and obesity in middle age are linked to increased future dementia risk in old age. However, when examined in old age, higher BMIs are associated with better cognition and decreased mortality. Little is known about the optimal BMI for well-being and survival in populations already suffering from dementia. Lifetime trends in weight, rather than single measures, might predict prognosis better and help untangle these apparent contradictions. Thus, the need arises to properly monitor BMI trends in affected dementia patients. Registries can include BMI, improving the management of dementia patients throughout the whole course of the disease. The role of central obesity and systemic inflammation on brain pathology and cognitive decline are discussed in this review. Understanding the life-course changes in BMI and their influence on dementia risk, cognitive prognosis and mortality after diagnosis may provide new insights into the underlying pathophysiology of dementia and shape possible intervention and treatment strategies.

Acute consumption of a high-fat diet prior to ischemia-reperfusion results in cardioprotection through NF-κB-dependent regulation of autophagic pathways

Previous studies have demonstrated improvement of cardiac function occurs with acute consumption of a high-fat diet (HFD) after myocardial infarction (MI). However, no data exist addressing the effects of acute HFD upon the extent of injury after MI. This study investigates the hypothesis that short-term HFD, prior to infarction, protects the heart against ischemia-reperfusion (I/R) injury through NF-κB-dependent regulation of cell death pathways in the heart. Data show that an acute HFD initiates cardioprotection against MI (>50% reduction in infarct size normalized to risk region) after 24 h to 2 wk of HFD, but protection is completely absent after 6 wk of HFD, when mice are reported to develop pathophysiology related to the diet. Furthermore, cardioprotection after 24 h of HFD persists after an additional 24 h of normal chow feeding and was found to be dependent upon NF-κB activation in cardiomyocytes. This study also indicates that short-term HFD activates autophagic processes (beclin-1, LC-3) preischemia, as seen in other protective stimuli. Increases in beclin-1 and LC-3 were found to be NF-κB-dependent, and administration of chloroquine, an inhibitor of autophagy, abrogated cardioprotection. Our results support that acute high-fat feeding mediates cardioprotection against I/R injury associated with a NF-κB-dependent increase in autophagy and reduced apoptosis, as has been found for ischemic preconditioning.

Favorable functional recovery in overweight ischemic stroke survivors: findings from the China National Stroke Registry

BACKGROUND

Obesity paradox has been reported because of the inverse relationship between the body mass index (BMI) and mortality in stroke patients. The relationship between BMI and functional recovery in stroke survivors is less well established. We explored the impact of BMI on functional recovery and mortality in stroke patients in the China National Stroke Registry (CNSR).

METHODS

Patients were consecutively recruited based on a standard protocol and prospectively followed up for outcomes at 3 months after disease onset. Patients were divided into 5 groups according to their BMI: underweight (<18.5 kg/m(2)), normal weight (18.5-22.9 kg/m(2)), overweight (23-27.4 kg/m(2)), obese (27.5-32.4 kg/m(2)), or severely obese (≥32.5 kg/m(2)). Multivariate logistic regression was performed to analyze the association between BMI and functional recovery or mortality.

RESULTS

CNSR enrolled 22,216 patients hospitalized for acute cerebrovascular events, and 10,905 eligible acute ischemic stroke patients were analyzed in our study. Favorable functional recovery (modified Rankin Scale score 0-1) was seen in 52.4% of underweight, 55.0% of normal weight, 61.0% of overweight, 59.2% of obese, and 60.3% of severely obese stroke survivors (P < .001). Overweight was independently associated with favorable 3-month functional recovery (odds ratio [OR] 1.24; 95% confidence interval [CI] 1.12-1.38). Mortality rate was 14.9% in underweight, 7.8% in normal weight, 7.1% in overweight, 7.2% in obese, and 11.5% in severely obese patients (P < .001). Severe obesity was independently associated with higher 3-month mortality (OR 2.01; 95% CI 1.10-3.69).

CONCLUSIONS

The stroke obesity paradox can be extended to include functional recovery but should not be interpreted as the fatter the better.