Objective To explore the clinical characteristics of patients with connective tissue disease with positive anti-small ubiquitin-like modifier activating enzyme (SAE) antibodies. MethodsRetrospectively select the patients who completed the screening of myositis autoantibodies in West China Hospital of Sichuan University between January 1, 2015 and May 30, 2021. Meanwhile, patients with positive anti-SAE antibodies were screened out. According to the clinical data of anti-SAE antibodies positive patients, they were divided into the following groups: tumor group and non-tumor group, ILD group and non-ILD group, inflammatory myopathy group and non-inflammatory myopathy group. Clinical symptoms, signs, laboratory examinations, imaging examinations and other clinical data of the above patients were collected. Results A total of 1 594 patients were screened for myositis autoantibodies, of which 56 were positive for anti-SAE antibodies, with a positive rate of 3.5%. In 56 patients, 32.1% in skin involvement, 35.7% in muscle involvement, 12.5% in joint involvement, 5.4% in dysphagia, 5.4% in weight loss, 58.9% in patients with interstitial lung disease (ILD) and 12.5% in patients with tumor history. There was no significant difference in age, sex, skin involvement, muscle involvement, joint involvement and respiratory system involvement between the tumor group and the non-tumor group (P>0.05). Except for age, the frequency of muscle involvement, and positive rate of anti-Ro-52 antibody, there was no significant difference in other indicators between the ILD group and the non-ILD group (P>0.05). Except for the positive rate of ILD, the frequency of skin involvement, the frequency of muscle involvement, the level of creatine kinase and hydroxybutyrate dehydrogenase (P<0.05), there was no significant difference in other indexes between the non-inflammatory myopathy group and the inflammatory myopathy group (P>0.05). Conclusions The patients with positive anti-SAE antibodies mainly present skin and muscle symptoms, and are prone to ILD, malignant tumor and dysphagia. Patients with positive anti-SAE antibodies and ILD were older, had less muscle damage, and had a higher positive rate of anti-Ro-52 antibody. Anti-SAE antibodies appear not only in patients with inflammatory myopathy, but also in non-inflammatory myopathy, often associated with a higher frequency of ILD and less muscle involvement.
Objective To investigate independent prognostic factors influencing the prognosis of connective tissue disease-associated interstitial lung disease with pulmonary hypertension (CTD-ILD-PH), and construct a nomogram model using machine learning to predict 1-, 3- and 5-year mortality risks, providing evidence for clinical diagnosis and treatment. Methods Patients diagnosed with CTD-ILD-PH and treated at the First Affiliated Hospital of Zhengzhou University from February 2011 to June 2021 were screened. The least absolute shrinkage and selection operator (Lasso), univariate Cox regression, and multivariate Cox regression analyses were combined to identify independent prognostic factors for CTD-ILD-PH patients. A novel nomogram prognostic model was constructed and internally validated using 1000 bootstrap resamples. The receiver operating characteristic (ROC) curve and Harrell's C-index assessed the predictive performance of the model. Calibration curves evaluated the model fit. Decision curve analysis (DCA) assessed the clinical utility of the model, and external validation was conducted using a separate test set. Results The study included 313 patients, with 108 deaths observed during the follow-up. Using the Lasso-Cox method, albumin, alanine aminotransferase (ALT), red cell volume distribution width (RDW), age, smoking history, rural residence, and pulmonary artery systolic pressure were identified as independent prognostic factors. The Harrell's C-index in the training set was 0.802, and the area under ROC curve was 0.880 (95%CI 0.833 - 0.928). Internal validation showed an average Harrell's C-index of 0.791. Calibration curves indicated high consistency between predicted and observed results. DCA confirmed the model's good clinical utility. External validation results demonstrated the model's favorable predictive performance and clinical utility. Conclusions Our research suggest that lower albumin, elevated ALT, elevated RDW, advanced age, smoking history, rural areas and higher pulmonary artery systolic blood pressure are independent prognostic risk factors for patients with CTD-ILD-PH. In this study, a prognostic model was developed for the first time to predict 1-, 3- and 5-year mortality in CTD-ILD-PH patients, which provides some reference value for future mortality risk assessment in CTD-ILD-PH.