Body Mass Index and the Risk of Poor Outcome in Surgically Treated Patients With Good-Grade Aneurysmal Subarachnoid Hemorrhage

Clinical impact of body mass index on outcomes of ischemic and hemorrhagic strokes

BACKGROUND AND AIM

To investigate the prognostic implication of body mass index (BMI) on clinical outcomes after acute ischemic and hemorrhagic stroke.

METHODS

The subjects of the study included adult patients with available baseline body weight and height data who had suffered an acute stroke and were registered in the Japan Stroke Data Bank-a hospital-based, multicenter stroke registration database-between January 2006 and December 2020. The outcome measures included unfavorable outcomes defined as a modified Rankin Scale (mRS) score of 5-6 and favorable outcomes (mRS 0-2) at discharge, and in-hospital mortality. Mixed effects logistic regression analysis was conducted to determine the relationship between BMI categories (underweight, normal weight, overweight, class I obesity, class II obesity; <18.5, 18.5-23.0, 23.0-25.0, 25-30, ⩾30 kg/m2) and the outcomes, after adjustment for covariates.

RESULTS

A total of 56,230 patients were assigned to one of the following groups: ischemic stroke (IS, n = 43,668), intracerebral hemorrhage (ICH, n = 9741), and subarachnoid hemorrhage (SAH, n = 2821). In the IS group, being underweight was associated with an increased likelihood of unfavorable outcomes (odds ratio, 1.47 (95% confidence interval (CI):1.31-1.65)) and in-hospital mortality (1.55 (1.31-1.83)) compared to outcomes in those with normal weight. Being overweight was associated with an increased likelihood of favorable outcomes (1.09 (1.01-1.18)). Similar associations were observed between underweight and these outcomes in specific IS subtypes (cardioembolic stroke, large artery stroke, and small-vessel occlusion). Patients with a BMI ⩾30.0 kg/m2 was associated with an increased likelihood of unfavorable outcomes (1.44 (1.01-2.17)) and in-hospital mortality (2.42 (1.26-4.65)) in large artery stroke. In patients with ICH, but not those with SAH, being underweight was associated with an increased likelihood of unfavorable outcomes (1.41 (1.01-1.99)).

CONCLUSIONS

BMI substantially impacts functional outcomes following IS and ICH. Lower BMI consistently affected post-stroke disability and mortality, while higher BMI values similarly affected these outcomes after large artery stroke.

Risk factors for poor outcome after aneurysmal subarachnoid hemorrhage in patients with initial favorable neurological status

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) remains a devastating diagnosis. A poor outcome is known to be highly dependent on the initial neurological status. Our goal was to identify other parameters that favor the risk of complications and poor outcome in patients with aSAH and initially favorable neurologic status.

METHODS

Consecutive aSAH cases treated at our hospital between 01/2003 and 06/2016 with the initial World Federation of Neurosurgical Societies grades I-III were included. Data on demographic characteristics, previous medical history, initial aSAH severity, and functional outcome after aSAH were collected. The study endpoints were the occurrence of cerebral infarcts, in-hospital mortality, and unfavorable outcome at 6 months after aSAH (modified Rankin scale > 3).

RESULTS

In the final cohort (n= 582), the rate of cerebral infarction, in-hospital mortality, and unfavorable outcome was 35.1%, 8.1%, and 17.6% respectively. The risk of cerebral infarction was independently related to the presence of acute hydrocephalus (adjusted odds ratio [aOR]=2.33, p<0.0001), aneurysm clipping (aOR=1.78, p=0.003), and use of calcium channel blockers concomitant to nimodipine (aOR=2.63, p=0.002). Patients' age (>55 years, aOR=4.24, p<0.0001), acute hydrocephalus (aOR=2.43, p=0.036), and clipping (aOR=2.86, p=0.001) predicted in-hospital mortality. Baseline characteristics associated with unfavorable outcome at 6 months were age (aOR=2.77, p=<0.0001), Fisher grades III-IV (aOR=2.81, p=0.016), acute hydrocephalus (aOR=2.22, p=0.012), clipping (aOR=3.98, p<0.0001), admission C-reactive protein>1mg/dL (aOR=1.76, p=0.035), and treatment intervals (aOR=0.64 per-5-year-intervals, p=0.006).

CONCLUSIONS

Although cerebral infarction is a common complication in aSAH individuals with favorable initial clinical condition, >80% of these patients show favorable long-term outcome. The knowledge of outcome-relevant baseline characteristics might help to reduce the burden of further complications and poor outcome in aSAH patients who tolerated the initial bleeding event well.

The impact of previous health on the mortality after aneurysmal subarachnoid hemorrhage: analysis of a prospective Swedish multicenter study

PURPOSE

There is an an increasing awareness of the importance of health and lifestyle for stroke diseases like spontaneous subarachnoid hemorrhage (SAH). However, the importance of pre-existing medical conditions for clinical course and mortality after SAH has not been studied. The aim of the present study was to identify pre-existing conditions contributing to mortality after SAH.

METHODS

Data were extracted from a Swedish national prospective study on patients with SAH. Variables were defined for age, sex, body mass index (BMI), clinical condition at admission, and for 10 pre-existing medical conditions. Models predicting mortality in three time intervals with all possible subsets of these variables were generated, compared and selected using Akaike's information criterion.

RESULTS

1155 patients with ruptured aneurysms were included. The mortality within 1 week was 7.6%, 1 month 14.3%, and 1 year 18.7%. The most common pre-existing medical conditions were smoking (57.6%) and hypertension (38.7%). The model's best predicting mortality within 1 week and from 1 week to 1 month included only the level of consciousness at admission and age, and these two variables were present in all the models among the top 200 in Akaike score for each time period. The most predictive model for mortality between 1 month and 1 year added previous stroke, diabetes, psychiatric disease, and BMI as predictors.

CONCLUSION

Mortality within the first month was best predicted simply by initial level of consciousness and age, while mortality within from 1 month to 1 year was significantly influenced by pre-existing medical conditions.

Risk Factors for Delayed Cerebral Ischemia in Good-Grade Patients With Aneurysmal Subarachnoid Hemorrhage

Background A subset of good-grade patients with aneurysmal subarachnoid hemorrhage (aSAH) develop delayed cerebral ischemia (DCI) that may cause permanent disabilities after aSAH. However, little is known about the risk factors of DCI among this specific patient group. Methods and Results We obtained a multinational cohort of good-grade (Glasgow Coma Scale 13-15 on admission) patients with aSAH by pooling patient data from 4 clinical trials and 2 prospective cohort studies. We collected baseline data on lifestyle-related factors and the clinical characteristics of aSAHs. By calculating fully adjusted risk estimates for DCI and DCI-related poor outcome, we identified the most high-risk patient groups. The pooled study cohort included 1918 good-grade patients with aSAH (median age, 51 years; 64% women), of whom 21% and 7% experienced DCI and DCI-related poor outcome, respectively. Among men, patients with obesity and (body mass index ≥30 kg/m²) thick aSAH experienced most commonly DCI (33%) and DCI-related poor outcome (20%), whereas none of the normotensive or young (aged <50 years) men with low body mass index (body mass index <22.5 kg/m²) had DCI-related poor outcome. In women, the highest prevalence of DCI (28%) and DCI-related poor outcome (13%) was found in patients with preadmission hypertension and thick aSAH. Conversely, the lowest rates (11% and 2%, respectively) were observed in normotensive women with a thin aSAH. Conclusions Increasing age, thick aSAH, obesity, and preadmission hypertension are risk factors for DCI in good-grade patients with aSAH. These findings may help clinicians to consider which good-grade patients with aSAH should be monitored carefully in the intensive care unit.