Cardiovascular and cerebrovascular diseases are characterized by high rates of morbidity and mortality. Microbiota is closely associated with cardiovascular disease. We aimed to comprehensively analyze the microbiotas of 300 healthy controls, 300 patients with high blood pressure (HBP), and 300 patients with coronary heart disease (CHD). The results indicated no significant difference in microbiota diversity among the three groups ( P > 0.05 ). However, differences in microbiota richness among the three groups were significant ( P < 0.05 ). Bacteroidetes and Bacteroidia were the dominant bacteria in the CHD group, Enterobacteriales and Escherichia-shigella in the HBP group, and Acidaminococcaceae and Phascolarctobacterium in the healthy control group. The prediction results of the random forest model indicated that the population with CHD displayed prominent features with high sensitivity, indicating that microbiota detection might become a novel clinical indicator to predict and monitor the risk of cardiovascular events. The prediction of microbiota function suggested differences in oxygen supply and chronic inflammation between populations with HBP/CHD and healthy populations. Although there is no difference in gut microbiota diversity among the three groups, each group has its dominant microbiota in terms of richness.

Background Gastric cancer (GC) is one of the most common malignant tumors in humans. Carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, and CA72-4 are all serum tumor markers for diagnosis of gastric cancer. However, the results of studies reporting the diagnosis of the combined three varied. In this study, the combined diagnostic performance of these 3 serum tumor markers was systematically evaluated. Methods PubMed, Embase, The Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang data were searched for literature on serum tumor markers CEA, CA19-9, and CA72-4 in the diagnosis of gastric cancer. The inclusion criteria were designed according to the Participants, Intervention, Control, Outcomes, Study (PICOS) principles. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) scoring scale was used to assess the quality of the literature. After extracting the data, Stata 16.0 software was used for meta-analysis. Results A total of 10 articles were finally included, and a total of 6,574 patients participated in diagnosis, 3,077 for confirmed GC and 3,497 for non-GC respectively. Meta-analysis results showed that the diagnostic sensitivity of the combined diagnosis of the 3 tumor markers was 0.67 [95% confidence interval (CI): 0.54, 0.77], the specificity was 0.89 (95% CI: 0.82, 0.93), the positive likelihood ratio was 5.9 (95% CI: 3.5, 9.8), the negative likelihood ratio was 0.38 (95% CI: 0.27, 0.53), and the diagnostic odds ratio (DOR) was 16 (95% CI: 8, 32). The diagnostic sensitivity of CA72-4 diagnosis alone was 0.58 (95% CI: 0.40, 0.73), specificity was 0.86 (95% CI: 0.80, 0.90), the positive likelihood ratio was 4.0 (95% CI: 3.1, 5.1), the negative likelihood ratio was 0.49 (95% CI: 0.34, 0.71), and the DOR was 8 (95% CI: 5, 14). The area under the ROC curve (AUC) values of the combined three diagnosis and CA72-4 diagnosis alone were 0.87 (95% CI: 0.83, 0.89) and 0.84 (95% CI: 0.81, 0.87), respectively, the difference was statistically significant (Z=4.86, P<0.05). Discussion The combined use of the 3 tumor markers has higher sensitivity and specificity than single marker diagnosis in the diagnosis of gastric cancer.