Risk factors assessment and a Bayesian network model for predicting ischemic stroke in patients with cardiac myxoma.

Objective: This study aims to identify relevant risk factors, assess the interactions between variables, and establish a predictive model for ischemic stroke (IS) in patients with cardiac myxoma (CM) using the Bayesian network (BN) approach. Methods: Data of patients with CM were collected from three tertiary comprehensive hospitals in Beijing from January 2002 to January 2022. Age, sex, medical history, and information related to CM were extracted from the electronic medical record system. The BN model was constructed using the tabu search algorithm, and the conditional probability of each node was calculated using the maximum likelihood estimation method. The probability of each node of the network and the interrelationship between IS and its related factors were qualitatively and quantitatively analyzed. A receiver operating characteristic (ROC) curve was also plotted. Sensitivity, specificity, and area under the curve (AUC) values were calculated and compared between the BN and logistic regression models to evaluate the efficiency of the predictive model. Results: A total of 416 patients with CM were enrolled in this study, including 61 with and 355 without IS. The BN model found that cardiac symptoms, systemic embolic symptoms, platelet counts, and tumor with high mobility were directly associated with the occurrence of IS in patients with CM. The BN model for predicting CM-IS achieved higher scores on AUC {0.706 [95% confidence interval (CI), 0.639-0.773]} vs. [0.697 (95% CI, 0.629-0.766)] and sensitivity (99.44% vs. 98.87%), but lower scores on accuracies (85.82% vs. 86.06%) and specificity (6.56% vs. 11.48%) than the logistic regression model. Conclusion: Cardiac symptoms, systemic embolic symptoms, platelet counts, and tumor with high mobility are candidate predictors of IS in patients with CM. The BN model was superior or at least non-inferior to the traditional logistic regression model, and hence is potentially useful for early IS detection, diagnosis, and prevention in clinical practice.

Clinical features, risk factors and survival in cardiac myxoma-related ischemic stroke: A multicenter case-control study.

BACKGROUND: Cardiac myxoma (CM) is an important etiology of stroke in young adults, but studies on CM-related ischemic stroke (CM-IS) are limited and conflicting. Hence, we investigated clinical characterizations, risk factors of CM-IS, and short-term survival after surgical resection. METHODS: We performed a retrospective analysis of data from all CM patients at three referral management centers and conducted follow-up examination. RESULTS: Among 414 CM patients, 402 were recruited for further analysis, including 54 patients with CM-IS and 348 patients with CM without stroke (Non-stroke). In the acute phase, patients presented with NIHSS 3 (interquartile range: 0-10) and clinical presentation comprising neurological, cardiac and constitutional symptoms. Multivariate analysis showed that the factors associated with an increased risk of CM-IS were tumor width < 30 mm [OR = 2.652, 95% CI: 1.061-6.627, P = 0.037], tumors with high-mobility (OR = 2.700, 95% CI: 1.357-5.371, P = 0.005), thrombus on the tumor surface (OR = 1.856, 95% CI: 1.003-3.434, P = 0.049), and lower B-type natriuretic peptide (BNP) levels (OR = 0.995, 95% CI: 0.989-0.999, P = 0.047). The overall three-year survival rate was 95.7% (95% CI: 94.9-96.5) in CM-IS patients who underwent surgery. CONCLUSIONS: CM-IS patients had mild or moderate neurologic deficits with various presentations at disease onset. Narrower tumor width, tumors with high-mobility, thrombus on the tumor surface, and lower BNP levels are potential predictors of CM-IS development. Surgical removal of CM is safe and efficacious in patients with CM-IS.

Risk factors and a Bayesian network model to predict ischemic stroke in patients with dilated cardiomyopathy.

Objective: This study aimed to identify risk factors and create a predictive model for ischemic stroke (IS) in patients with dilated cardiomyopathy (DCM) using the Bayesian network (BN) approach. Materials and methods: We collected clinical data of 634 patients with DCM treated at three referral management centers in Beijing between 2016 and 2021, including 127 with and 507 without IS. The patients were randomly divided into training (441 cases) and test (193 cases) sets at a ratio of 7:3. A BN model was established using the Tabu search algorithm with the training set data and verified with the test set data. The BN and logistic regression models were compared using the area under the receiver operating characteristic curve (AUC). Results: Multivariate logistic regression analysis showed that hypertension, hyperlipidemia, atrial fibrillation/flutter, estimated glomerular filtration rate (eGFR), and intracardiac thrombosis were associated with IS. The BN model found that hyperlipidemia, atrial fibrillation (AF) or atrial flutter, eGFR, and intracardiac thrombosis were closely associated with IS. Compared to the logistic regression model, the BN model for IS performed better or equally well in the training and test sets, with respective accuracies of 83.7 and 85.5%, AUC of 0.763 [95% confidence interval (CI), 0.708-0.818] and 0.822 (95% CI, 0.748-0.896), sensitivities of 20.2 and 44.2%, and specificities of 98.3 and 97.3%. Conclusion: Hypertension, hyperlipidemia, AF or atrial flutter, low eGFR, and intracardiac thrombosis were good predictors of IS in patients with DCM. The BN model was superior to the traditional logistic regression model in predicting IS in patients with DCM and is, therefore, more suitable for early IS detection and diagnosis, and could help prevent the occurrence and recurrence of IS in this patient cohort.

Increased CD8+ central memory T cells in patients with multiple sclerosis.

A T-cell-mediated autoimmune process against central nervous system myelin is believed to underlie the pathogenesis of multiple sclerosis (MS). Formation of immunological memory is based on the differentiation of naïve T cells to memory T cells after exposure to antigens and specific cytokines. The aim of this study was to analyse peripheral blood mononuclear cells in patients with MS for different T-cell subsets including naïve and memory T cells. Flow cytometry and enzyme-linked immunosorbent assay were used to analyse memory T-cell subsets and plasma concentration of interleukin-15 (IL-15) in peripheral blood of MS patients, patients with other neurological disorders and healthy controls. MS patients had a skewed distribution of T cells with an increased level of CD8+/CCR7+/CD45RA - central memory T cells (TCM) compared to healthy controls. In addition, MS patients showed significantly higher levels of plasma IL-15 than healthy controls did. Upregulated CD8+ TCM in MS patients may reflect a persistent chronic inflammatory response that may have been induced during early stages of the disease. This derangement may be important for maintaining chronic inflammation in MS.

[Influence of beta-endorphin on function of immune system of patients with cerebral hemorrhage].

OBJECTIVE: To study the influence of beta-endorphin (beta end) on the function of immune system of patients with cerebral hemorrhage at different stages. METHODS: Radioimmunal analysis was applied to detect the serum beta-endorphin concentration in the peripheral blood of 28 patients with cerebral hemorrhage, aged 65.5 +/- 13, 28 age-matched patients with cerebral thrombosis, and 28 sex and age-matched normal controls. Mononuclear cells from peripheral blood of these 3 kinds of subjects were cultured and then beta end 10(-8) g/L, beta end 10(-11) g/L, beta end 10(-14) g/L, or beta end 10(-11) g/L + naloxone 10(-5) g/L were added into the media respectively and the MNCs were cultured for more 24 hours (beta end 10(-8) g/L group, beta end 10(-11) g/L group, beta end 10(-14) g/L group, and beta end 10(-11) g/L + Nal group). Another MNCs were cultured without addition of beta end (beta end 0 g/L group). Then the MNCs were collected. RT-PCR was used to detect the expressions of interleukin (IL)-1beta, IL-2, IL-8 and iNOS mRNA in the MNCs. RESULTS: The serum beta-end level of the patients with cerebral hemorrhage at the acute stage was 129 +/- 82 ng/L, significantly lower than that of the normal controls (321 +/- 62 ng/L, P<0.01) and that of the patients with cerebral thrombosis (264 +/- 163 ng/L, P<0.05), but not significantly different from that of the patients with cerebral hemorrhage in the convalescent stage (160 +/- 72 ng/L, P>0.05). The expression of IL-1beta and the expression of IL-2 of the patients with cerebral hemorrhage at the acute stage were significantly lower than those of the patients with cerebral thrombosis and the controls (all P<0.01). The expression of IL-1beta of the patients with cerebral hemorrhage at the convalescent stage were higher than that in the acute stage, however, the difference was not significant (P>0.05). The expression of IL-2 of the patients with cerebral hemorrhage at the convalescent stage was higher than that at the acute stage (P<0.01). The expression of IL-8 and the expression of iNOS of the patients with cerebral hemorrhage at the acute stage were significantly higher than those of the patients of cerebral thrombosis and the controls (both P<0.01). The expression of IL-8 and the expression of iNOS of the patients with cerebral hemorrhage at the convalescent stage were significantly lower than those in the acute stage (both P<0.01). The expressions of IL-1beta, IL-2, IL-8, and iNOS mRNA in the peripheral blood MNCs in vitro in the beta end 10(-8) g/L group and beta end 10(-11) g/L group were significantly higher than those of the beta end 0 g/L group, beta end 10(-11) g/L group, and beta-end 10(-11) g/L + Nal 10(-5)g/L group. The expressions of IL-1beta, IL-2, IL-8, and iNOS mRNA in the peripheral blood MNCs in the beta-end 10(-11) g/L +Nal 10(-5) g/L group were higher than those of the beta end 0 g/L group, however, not significantly. CONCLUSIONS: The endogenous beta-endorphin level of cerebral hemorrhage patients is low. The immune system function is up-regulated at the acute stage and then down-regulated. Thereafter the immune system function is invariably low. Exogenous beta-endorphin enhances the IL-1 beta, IL-2, IL-8 and iNOS mRNA expression of peripheral blood MNCS. beta-endorphin receptor antagonist naloxone blocks the positive immunoregulation by beta-endorphin.