Development and validation of a nomogram model for all-cause mortality risk in patients with acute myocardial infarction complicated by impaired activity daily living

Background Activity daily living (ADL) is a critical indicator for assessing functional status in patients. Previous studies have shown that impaired ADL is associated with poor prognosis in patients of acute myocardial infarction (AMI). However, there is currently a lack of effective predictive tools for assessing the all-cause mortality risk in AMI patients with ADL impairment. Purpose The aim of this study is to identify risk factors for all-cause mortality in AMI patients with ADL impairment and to develop a risk prediction model. Methods We conducted a multicenter retrospective cohort study analyzing data from 82 hospitals, from January 2010 to December 2024. Inclusion criteria included patients who had an ADL assessment before admission and were diagnosed with AMI at discharge. ADL was assessed using Barthel Index (BI), which obtained from patients’ resident health records. Patients were classified into four groups based on the BI score, 100: full independence, 61-99: mild dependence, 41-60: moderate dependence, 0-40: complete dependence. AMI patients were randomly divided into training and validation cohorts in a 7:3 ratio. A nomogram prediction model for all-cause mortality in AMI patients with ADL impairment was developed and validated. The Receiver Operating Characteristic (ROC) curve was plotted, and the Area Under the Curve (AUC) was calculated to assess the discrimination. Results We included 60,424 eligible patients, of whom 57,692 were fully independent, 1,896 had mild dependence, 552 had moderate dependence, and 284 were completely dependent. Baseline characteristics, medical history, and other variables were included in the Lasso regression analysis, with the optimal value selected as the λ corresponding to one standard error from the minimum value. Finally, nine predictive factors were identified to construct a nomogram prediction model for all-cause mortality in AMI patients with ADL impairment: ADL, age, Killip classification, presence of ST-segment elevation myocardial infarction (STEMI), history of stroke, diabetes, atrial fibrillation, valvular heart disease, and malignancy (Figure 1). In the training cohorts, the nomogram model showed AUCs of 0.804, 0.802, and 0.802 for 6 months, 1 year, and 2 years, respectively (Figure 2A), while in the validation cohorts, the AUCs were 0.808, 0.805, and 0.803, respectively (Figure 2B). Conclusions We developed a nomogram prediction model for all-cause mortality in AMI patients with ADL impairment. This model provides a simple assessment tool for clinicians to improve the clinical management of these patients.