A predictive analytics model for differentiating between transient ischemic attacks (TIA) and its mimics.
区分短暂性脑缺血发作 (TIA) 及其模拟物的预测分析模型。
- 作者列表："Stanciu A","Banciu M","Sadighi A","Marshall KA","Holland NR","Abedi V","Zand R
BACKGROUND:Transient ischemic attack (TIA) is a brief episode of neurological dysfunction resulting from cerebral ischemia not associated with permanent cerebral infarction. TIA is associated with high diagnostic errors because of the subjective nature of findings and the lack of clinical and imaging biomarkers. The goal of this study was to design and evaluate a novel multinomial classification model, based on a combination of feature selection mechanisms coupled with logistic regression, to predict the likelihood of TIA, TIA mimics, and minor stroke. METHODS:We conducted our modeling on consecutive patients who were evaluated in our health system with an initial diagnosis of TIA in a 9-month period. We established the final diagnoses after the clinical evaluation by independent verification from two stroke neurologists. We used Recursive Feature Elimination (RFE) and Least Absolute Shrinkage and Selection Operator (LASSO) for prediction modeling. RESULTS:The RFE-based classifier correctly predicts 78% of the overall observations. In particular, the classifier correctly identifies 68% of the cases labeled as "TIA mimic" and 83% of the "TIA" discharge diagnosis. The LASSO classifier had an overall accuracy of 74%. Both the RFE and LASSO-based classifiers tied or outperformed the ABCD2 score and the Diagnosis of TIA (DOT) score. With respect to predicting TIA, the RFE-based classifier has 61.1% accuracy, the LASSO-based classifier has 79.5% accuracy, whereas the DOT score applied to the dataset yields an accuracy of 63.1%. CONCLUSION:The results of this pilot study indicate that a multinomial classification model, based on a combination of feature selection mechanisms coupled with logistic regression, can be used to effectively differentiate between TIA, TIA mimics, and minor stroke.
背景: 短暂性脑缺血发作 (Transient ischemic attack，TIA) 是由脑缺血引起的神经功能障碍的短暂发作，与永久性脑梗死无关。由于结果的主观性以及缺乏临床和影像学生物标志物，TIA 与高诊断误差相关。本研究的目的是设计和评估一种新的多项分类模型，基于特征选择机制与逻辑回归的结合，预测 TIA 的可能性，TIA 模拟,和轻微中风。 方法: 我们对在我们的卫生系统中评估的 9 个月内初步诊断为 TIA 的连续患者进行了建模。我们通过两名卒中神经科医生的独立验证，建立了临床评估后的最终诊断。我们使用递归特征消除 (RFE) 和最小绝对收缩和选择算子 (LASSO) 进行预测建模。 结果: 基于 RFE 的分类器正确预测了 78% 的总体观察结果。特别是，分类器正确识别 68% 标记为 “TIA 模拟” 的病例和 83% 的 “TIA” 出院诊断。套索分类器的总准确度为 74%。基于 RFE 和 LASSO 的分类器均并列或优于 ABCD2 评分和 TIA 诊断 (DOT) 评分。关于预测 TIA，基于 RFE 的分类器具有 61.1% 的准确性，基于 LASSO 的分类器具有 79.5% 的准确性，而应用于数据集的点分数产生 63.1% 的准确性。 结论: 这项初步研究的结果表明，基于特征选择机制与逻辑回归相结合的多项分类模型可用于有效区分 TIA 、 TIA 模拟物、和轻微中风。
METHODS:BACKGROUND:People with stroke are not meeting recommended levels of physical activity. The modifiable factors associated with post-stroke physical activity levels need to be identified to develop targeted interventions. OBJECTIVE:The objective of this study was to investigate the factors at discharge from inpatient rehabilitation that are associated with physical activity levels at 3 months following discharge. DESIGN:This was a prospective cohort study. METHODS:Sixty-four people with stroke completed baseline assessments at discharge from inpatient rehabilitation and 55 completed the follow-up 3 months later. The candidate factors (i.e. gait speed, balance, strength, cognition, mood and motivation) were measured at discharge. The primary outcome measure at follow-up was walking related activity (measured by wrist-worn accelerometer). Secondary outcome measures were physical activity participation (Activity Card Sort) and intensity of physical activity (International Physical Activity Questionnaire - Short 7 days). Adjusted separate multivariable linear regression models or proportional odds regression models were used to evaluate the associations between candidate factors and physical activity. RESULTS:Gait speed and balance were associated with all aspects of physical activity. Higher level of intrinsic motivation was also associated with higher physical activity participation. Anxiety demonstrated a significant non-linear relationship with physical activity participation. LIMITATIONS:Inclusion of fatigue and individual muscle strength could have provided further insights into associations with steps per day. CONCLUSION:The results demonstrated that better physical function at discharge from inpatient rehabilitation was associated with future increased levels of physical activity. Additionally, higher levels of motivation impacted on increased physical activity participation. The influence of anxiety on physical activity participation requires further exploration. Mixed-method study designs can be utilized to further understand the factors associated with post-stroke physical activity.
METHODS:Cerebral ischemia-reperfusion (I/R) is characterized by initial transient cerebral ischemia followed by reperfusion. Various pathophysiological processes are involved in brain injury and functional recovery during cerebral I/R. There are few studies on dynamic metabolic process after cerebral I/R. The present study was to observe dynamic alteration of brain injury, functional recovery, and metabolites after cerebral I/R in rats and discover potential metabolic markers. The cerebral I/R model was established by middle cerebral artery occlusion (MCAO) for 90 min, following reperfusion in rats. The results of cerebral infarction area, cerebral edema, and behavior test showed that there were dynamic changes in brain injury and functional recovery at different periods after cerebral I/R. Further analysis showed that the brain injury was severe on the first day of cerebral I/R, and there was a significant functional recovery from the 7th day of cerebral I/R, followed by an aggravation trend of brain injury from the days 7 to 28. Furthermore, Matrix-assisted laser desorption ionization mass spectrometry imaging analysis showed that the expression of ATP, glucose, and citric acid on 7th day was the highest during cerebral I/R, which indicated that energy metabolism and oxidative phosphorylation played important roles during cerebral I/R. In addition, the untargeted metabolomic results showed that the level of isocitric acid, the ratio of oxyglutaric acid/glutamic acid, and the level of pyruvic acid associated with the TCA cycle were also the highest on the 7th day during cerebral I/R, which indicated that the transient spontaneous recovery of ischemic brain on the 7th day after ischemia-reperfusion might be related to oxidative phosphorylation and energy metabolism in the brain in this period. In conclusion, the results suggest that some small molecule metabolites participate in the brain injury and functional recovery during cerebral I/R, which is of great significance to the development of therapeutic drugs and diagnostic markers.
METHODS:The aims of this study were to study the effects of miR-2 on cerebral ischemia–reperfusion rats and to explore its further mechanism. Rats were assigned into sham, model, miR-22 control and miR-22 groups. Observation of neurological behaviors at 24 h after operation found that neurological functions were severely damaged in the model and miR-22 control groups and these damages were improved by miR-22. RT-PCR indicated that miR-22 mRNA level in the brain tissue was significantly decreased in the model and miR-22 control groups, but increased in the miR-22 group. TTC staining showed increased percentage of cerebral infarction volume in the model and miR-22 control groups and this increase was reduced by miR-22. Immunohistochemistry showed increased densities of CD34^+ and VEGF^+ microvessels in the cortex in the model and miR-22 control groups, which were further increased in the miR-22 group. ELISA showed increased serum VEGF and Ang-1 levels in the model and miR-22 control groups, which were also further increased in the miR-22 group. Western blot analysis showed increased phosphorylation level of PI3K and Akt in brain tissue in the model and miR-22 control groups, which were further increased in the miR-22 group. Administration of LY294002, a specific PI3K pathway inhibitor, significantly reversed all the effects of miR-22 on rats in the model group. miR-22 exerts its neuroprotective and angiogenic functions via the PI3K/Akt signaling pathway, at least partly, in rats under cerebral ischemia–reperfusion.