A previous meta-analysis by the US Food and Drug Administration (FDA) of antidepressant trials suggested that children who received antidepressants had twice the rate of suicidal ideation and behaviour than children who were given a placebo.
The authors of the new study, published in the journal JAMA Internal Medicine, sought to examine suicidal behaviour and antidepressant dose, and whether risk depended on a patient's age.
The rate of suicidal behaviour (deliberate self-harm or DSH) among children and adults (24 years or younger) who started antidepressant therapy at high doses was about twice as high compared with a matched group of patients who received generally prescribed doses.
The authors suggest this corresponds to about one additional event of DSH for every 150 patients treated with high-dose therapy.
The study does not address why higher doses might lead to higher suicide risk, researchers said.
