Authors: Alice Weatherston
Investigation by a team at The University of Nottingham (UK), led by Carol Coupland (University of Nottingham), revealed that associations between a range of antidepressant drugs and the rates of three different cardiovascular outcomes in individuals with depression aged under 65 years were not significant.
The research evaluated medical records from the UK QResearch database from 238,963 patients aged 20–64, all of which had been medically diagnosed with depression. All records were analyzed for the use of antidepressants and cardiovascular incidents, including heart attacks, strokes or transient ischemic attacks and arrhythmia.
Details of antidepressants prescribed from a range of different classes including tricyclic and related antidepressants, selective serotonin reuptake inhibitors and others, as well as dosage and duration of use over a 5 year period were collated. Factors such as age, sex, smoking status, alcohol consumption, comorbidities and use of other drugs were also accounted for.
Carol Coupland discussed the results: “We found no evidence that SSRIs were associated with an increased risk of arrhythmia, heart attacks, or stroke in people with depression over the 5 year period. But there was a significant doubling of risk for arrhythmia during the first four weeks of taking tricyclic and related antidepressants.”
Results also indicated that SSRIs, in particular fluoxetine, were linked to a reduction in heart attack risk. “Absolute risks of heart attacks were 6 per 10,000 for selective serotonin reuptake inhibitors over 1 year, and 4 per 10,000 for fluoxetine compared with 10 per 10,000 for non-use,” explained Coupland.
Importantly, citalopram, the most commonly prescribed antidepressant drug among patients in the study, was not shown to be associated with an increased risk of arrhythmia, even at higher doses. The researchers do warn however that caution should still be taken when prescribing the antidepressant, as only a relatively small number of patients in the study were on these high doses.
Although only an observational study, the findings highlight a key relationship to be analyzed further, especially given the prevalence of antidepressants. “These findings are reassuring in the light of recent cardiac safety concerns about selective serotonin reuptake inhibitors,” concluded the authors.