On Tuesday a study published in BMJ claimed there is no link between taking SSRI antidepressants and risk of heart problems. It is widely believed depression increases the risk of cardiovascular events. However, the role of antidepressants leading to an increase or decrease in risk of heart related issues is not proven.
In 2014 it was found 15.7 million adults over 18 years of age i.e., equal to 6.7% of adults in the U.S. suffered from a major depression episode over a period of 12 months. SSRI, short for selective serotonin reuptake inhibitors, are one of the most commonly used antidepressants, especially in the UK. In 2013, more than 53 million prescriptions for antidepressants were issued by physicians in UK and 54% of them were SSRIs. The most commonly used antidepressant being ‘Citalopram’ followed by ‘Fluoxetine’ and ‘Amitriptyline’.
SSRI Causes No Risk To Heart
A previous research on antidepressants, also published in BMJ, stated, “The safety concerns for antidepressants range from adverse effects that make patients feel unwell or prone to stopping medication through to an increase in suicidal thoughts to death either from completed suicide or cardiac arrhythmias.” However, this recent research clearly showed that SSRIs have no link with the cardiac arrhythmias.
Carol Coupland, a medical statistics in primary care professor at the University of Nottingham, and his team inspected associations between different heart anomalies and different antidepressant treatments. Three different cardiovascular outcomes, heart attacks, strokes or transient ischaemic attacks, and arrhythmia, particularly in individuals with depression were observed. Antidepressant classes such as tricyclic (TCA) and its related antidepressants, along with Selective Serotonin Reuptake Inhibitors (SSRIs), Monoamine Oxidase Inhibitors and even other types were assessed. The dosage and duration of the antidepressant used were also taken in consideration of results.
Previous observational studies on antidepressants involving younger people are restricted and none focused on younger people. It is assumed the effects of antidepressants on heart may vary according to age. In a meta-analysis involving 13 observational studies, the majority of participants were older people, with ages above 65 years. So use of SSRIs leading to myocardial infarction is uncertain. The current study used people between the age groups of 20 to 64 years old. The age limit was incorporated to gather more data on younger age groups.
The limitations of the research include exclusion of some important groups. Individuals with a previous diagnosis of bipolar disorder, schizophrenia and other type of psychosis were not included, because they were already on lithium or anti-manic drugs.
The analysis found about 772 patients had suffered from a myocardial infarction. Likewise, 1,106 of the participants had endured a stroke or a transient ischaemic attack. About 1,452 were found to have lived through an arrhythmia. All of the heart events had been documented during a five-year follow-up.
The study concluded there is no solid proof of an association between elevated risk of heart attacks, transient ischaemic attacks, stroke and arrhythmia in patients with depression prescribed SSRIs. The research did find one risk factor of taking SSRIs i.e., increase in arrhythmias risk. They observed the risk for arrhythmia doubled during the first four weeks of consuming tricyclic anti-depressants and other related antidepressants. However, use of fluoxetine indicated reduced risk of myocardial infarction.
The 11 anti-depressants drugs prescribed to the participants of the study included: Amitriptyline (TCA), Dosulepin (TCA), Lofepramine (TCA), Trazodone (TCA), Citalopram (SSRI), Escitalopram (SSRI), Fluoxetine (SSRI), Paroxetine (SSRI), Sertraline (SSRI), Mirtazapine (other) and Venlafaxine (other).
The following three drugs in the study showed results that are pertinent to mention here:
Fluoxetine — SSRI Antidepressant That Reduces The Chances Of Heart Attacks
The particular use of the SSRIs ‘Fluoxetine’ indicated a reduced risk of heart attacks. The patients were first prescribed fluoxetine at a mean age of 38.8 years. Fluoxetine was connected with having the lowest risks of arrhythmia and myocardial infarction. Overall it was found only six individuals per every 10,000 participants were at a risk of developing a heart attack. But only four individuals per every 10,000 participants who used fluoxetine had a risk of developing heart attack. The author concluded the results probe for further investigation into Fluoxetine.
Citalopram — A Controversial SSRI — Showed Reassuring Results
Most commonly used anti-depressant, Citalopram, was given to 31.5% of the patients in the study, with prescription first given at a mean age of 38.9 years. The current study based its observation on doses ranging between ≤20 mg/day, 20-39 mg/day, and ≥40 mg/day of Citalopram. It was discovered even very high doses i.e., ≥40 mg/day of Citalopram have no relation with an increased risk of arrhythmia.
However, the author did state they could not completely rule out the risk of developing arrhythmia in patients prescribed with high doses of citalopram because 28 patients, prescribed with very high doses developed arrhythmia. In 2011, the U.S. FDA has issued a warning regarding Citalopram, stating it should not be taken in doses greater than 40 mg/per day, based on previous studies.
But the current study concluded their results for citalopram are consistent when compared with other cohort studies, indicating the results are reassuring.
Lofepramine – Tri-Cyclic Reuptake Inhibitors (TCRI) That Showed Risks To Heart
Lofepramine showed a significantly increased risk of myocardial infarction and arrhythmia in patients. 30 patients out of 10,000 had suffered arrhythmia and 31 out of 10,000 had suffered from myocardial infarction after being prescribed Lofepramine over a period of five years.
Participants were chosen using the UK QResearch primary care database. A total of 238,963 patients were observed for heart problem with a previous diagnosis of depression, given out from 2000 to 2011. The participants were monitored and followed up until 2012. Other factors take into account included — age, sex, smoking status, alcohol consumption, co-morbidities and drug use. Individuals prescribed antidepressants before the start of the study date i.e., 1st January, 2000, or less than 20 years of age and those first diagnosed 36 months before the start were excluded.
The current research has provided essential data on younger age groups in relation to depression and heart diseases. Since age groups ranging from 20 and above 65 have now been covered, the next step would be to carry out a cohort study on adolescents. In 2014 it was estimated 2.8 million or 11.4% of the adolescents between the ages of 12 to 17 in the U.S. had at least one instance of depression.