The doctoral dissertation in the field of Cardiology will be examined at the Faculty of Health Sciences at the Kuopio Campus.
What is the topic of your doctoral research? Why is it important to study the topic?
Atrial fibrillation is the most common arrhythmia in women and men worldwide with a prevalence of approximately 1-4% in Western countries. The prevalence is estimated to increase by over 60% by 2050. Atrial fibrillation causes a five-fold increase in the risk of stroke and is responsible for 10-15% of ischemic strokes. Ageing, female sex and several comorbidities increase the risk of thromboembolic complications in atrial fibrillation. Oral anticoagulation reduces the thromboembolic risk by two thirds and is recommended for patients with atrial fibrillation and risk factors for stroke. Female and elderly patients with atrial fibrillation represent an increasing patient population with major health care costs.
What are the key findings or observations of your doctoral research?
The key findings of this dissertation showed that female sex and old age increase the risk of thromboembolic complications after electrical cardioversion of recent onset (< 48 hours) atrial fibrillation especially when delay to cardioversion > 12 hours. Moreover, women with a high risk of stroke were unsatisfactorily treated with oral anticoagulation. In patients with atrial fibrillation undergoing percutaneous coronary intervention octogenarians experienced a higher incidence of major cardiac and cerebrovascular events at 12-month follow-up with no sex-related difference.
How can the results of your doctoral research be utilised in practice?
The findings of this dissertation underscore that time to cardioversion ≥ 12 hours should be considered in risk stratification of patients undergoing cardioversion for recent onset atrial fibrillation and oral anticoagulation treatment should be initiated especially in elderly female patients with atrial fibrillation before cardioversion. Furthermore, there is a need to improve risk stratification and evidence-based oral anticoagulation especially in women with atrial fibrillation. Lastly, longer antithrombotic therapy might be considered in octogenarians, especially in those with acute coronary syndrome, but this assumption needs to be studied in adequately powered randomized trials.
Please describe the process of your doctoral research. For example, what are the key research methods and materials used in your doctoral research?
The aim of this dissertation was to evaluate sex- and age-related differences in anticoagulation treatment strategy and thromboembolic complications after cardiac procedures in atrial fibrillation patients. We investigated (1) the interaction of sex, age, and timing of electrical cardioversion on the risk of thromboembolic complications in patients with recent-onset (< 48 hours) atrial fibrillation not using periprocedural anticoagulation in the retrospective FinCV study from 2003 to 2010, (2) sex-related differences in the use of oral anticoagulation in atrial fibrillation patients suffering a stroke or intracranial bleed in the retrospective FibStroke study from 2003 to 2012, and (3) the impact of sex and age on the outcome of atrial fibrillation patients undergoing percutaneous coronary intervention in the prospective AFCAS study from 2008 to 2010.
The doctoral dissertation of Aissa Bah, Licentiate of Medicine, entitled The impact of sex and age in the treatment of patients with atrial fibrillation, will be examined at the Faculty of Health Sciences. The Opponent in the public examination will be Professor Katriina Aalto-Setälä of Tampere University, and the Custos will be Professor Juha Hartikainen of the University of Eastern Finland. The public examination will be held in Finnish.
Doctoral defence (in Finnish)
