A nomogram to predict unfavourable outcome in patients receiving oral anticoagulants for atrial fibrillation after stroke
Manuel Cappellari, David Seiffge, Masatoshi Koga, Maurizio Paciaroni, Stefano Forlivesi, Gianni Turcato, Paolo Bovi, Sohei Yoshimura, Kanta Tanaka, Masayuki Shiozawa, Takeshi Yoshimoto, Kaori Miwa, Masahito Takagi, Manabu Inoue, Hiroshi Yamagami, Valeria Caso, Georgios Tsivgoulis, Michele Venti, Monica Acciarresi, Andrea Alberti, Danilo Toni, Alexandros A. Polymeris, Bruno Bonetti, Giancarlo Agnelli, Ḱazunori Toyoda, Stefan T. Engelter, GM De Marchis, on behalf of the SAMURAI-NVAF, RAF-NOAC, NOACISP LONG-TERM, and Verona Study Groups
Abstract
Abstract Introduction It is unknown whether the type of treatment (direct oral anticoagulant versus vitamin K antagonist) and the time of treatment introduction (early versus late) may affect the functional outcome in stroke patients with atrial fibrillation. We aimed to develop and validate a nomogram model including direct oral anticoagulant/vitamin K antagonist and early/late oral anticoagulant introduction for predicting the probability of unfavourable outcome after stroke in atrial fibrillation-patients. Patients and Methods We conducted an individual patient data analysis of four prospective studies. Unfavourable functional outcome was defined as three-month modified Rankin Scale score 3 -6. To generate the nomogram, five independent predictors including age (<65 years, reference; 65--79; or 80), National Institutes of Health Stroke Scale score (0--5 points, reference; 6--15; 16--25; or >25), acute revascularisation treatments (yes, reference, or no), direct oral anticoagulant (reference) or vitamin K antagonist, and early (7 days, reference) or late (8--30) anticoagulant introduction entered into a final logistic regression model. The discriminative performance of the model was assessed by using the area under the receiver operating characteristic curve. Results A total of 2102 patients with complete data for generating the nomogram was randomly dichotomised into training (n = 1553) and test (n = 549) sets. The area under the receiver operating characteristic curve was 0.822 (95% confidence interval, CI: 0.800--0.844) in the training set and 0.803 (95% CI: 0.764--0.842) in the test set. The model was adequately calibrated (9.852; p = 0.276 for the Hosmer--Lemeshow test). Discussion and Conclusion Our nomogram is the first model including type of oral anticoagulant and time of treatment introduction to predict the probability of three-month unfavourable outcome in a large multicentre cohort of stroke patients with atrial fibrillation.