Depressed people have an increased risk of atrial fibrillation, according to a study (“Depression, antidepressants, and the risk of non-valvular atrial fibrillation: A nationwide Danish matched cohort study”) published in the European Journal of Preventive Cardiology. Medication was not responsible for the high frequency of atrial fibrillation in depressed people, stressed the researchers.
“It is common knowledge that there is a connection between the mind and the heart. Depression predicts the development of coronary artery disease and worsens its prognosis. Our study investigated whether depression is also linked with atrial fibrillation,” says study author Morten Fenger-Grøn, senior statistician, research unit for general practice, Aarhus University, Denmark.
Atrial fibrillation is the most common heart arrhythmia. It causes 20–30% of all strokes and increases the risk of dying prematurely. Previous studies have found associations between depression and both more severe symptoms and higher mortality in atrial fibrillation patients. Antidepressants have been linked with some serious, but rare, heart rhythm disturbances, prompting the question of whether they might also raise the risk of atrial fibrillation.
This study investigated the association of depression, and antidepressant treatment, with the risk of developing atrial fibrillation. Filling a prescription for antidepressants for the first time was used as an indicator of depression.
“Depression is associated with an increased risk of a series of cardiovascular diseases and with increased symptom burden in patients with atrial fibrillation. The aim of this study was to determine the association between depression as well as antidepressant treatment and the risk of incident atrial fibrillation.
“A nationwide register-based study comparing the atrial fibrillation risk in all Danes initiating antidepressant treatment from 2000 to 2013 (N¼785,254) with that in a 1:5-matched sample from the general population.
“Cox regression was used to estimate adjusted hazard ratios (aHRs) and associated 95% confidence intervals (95% CIs), both after initiation of treatment and in the month before when patients were assumed to have medically untreated depression.
“Antidepressant treatment was associated with a three-fold higher risk of atrial fibrillation during the first month (aHR¼3.18 (95% CI: 2.98–3.39)). This association gradually attenuated over the following year (aHR¼1.37 (95% CI: 1.31–1.44) 2–6 months after antidepressant therapy initiation, and aHR¼1.11 (95% CI: 1.06–1.16) 6–12 months after). However, the associated atrial fibrillation risk was even higher in the month before starting antidepressant treatment (aHR¼7.65 (95% CI: 7.05–8.30) from 30 to 15 days before, and aHR¼4.29 (95% CI: 3.94–4.67) the last 15 days before). Overall, 0.4% of patients were diagnosed with atrial fibrillation from 30 days before to 30 days after antidepressant treatment.
“Antidepressant users had a substantially increased atrial fibrillation risk, particularly before treatment initiation. Whether this mirrors a causal relation between depression and atrial fibrillation may have large consequences for public health and should be discussed.”
“Filling a prescription for antidepressants, which we used as an indicator of depression, was associated with a three-fold greater risk of atrial fibrillation. The decrease with time could suggest that treatment may alleviate this risk,” said Fenger-Grøn.
The risk of atrial fibrillation risk was even higher in the month before starting antidepressants. “This suggests that antidepressant medication itself is not associated with the development of atrial fibrillation,” he continues. “If you are depressed, there is no reason to worry that taking drug treatment will cause atrial fibrillation.”