Sertraline, one of the UK’s most commonly prescribed antidepressants, can improve key symptoms of depression such as low mood and suicidal thoughts within two weeks of treatment, according to a data analysis led by researchers at University College London (UCL).
The findings, published in the journal Nature Mental Health, challenge the results of a previous results from the PANDA trial from 2019, which suggested that the selective serotonin reuptake inhibitor (SSRI) may have an earlier impact on symptoms related to anxiety than those associated with depression.
The findings showed that sertraline improved anxiety symptoms and participants’ overall sense of mental health by six weeks, but that improvements in overall depressive symptoms were not seen until 12 weeks.
Effects of sertraline at two weeks
The latest study re-analysed the data, which included patients in England with depressive symptoms ranging from mild to moderate, using a more targeted statistical approach, and considered how specific symptoms respond to treatment.
Their analysis of 571 participants found that emotional and volitional symptoms – including sadness, restlessness and suicidal thoughts – began to improve after just two weeks on sertraline.
The largest beneficial effects of sertraline were on feelings of self-loathing, feeling bad about oneself and the inability to experience joy or pleasure (anhedonia).
By contrast, somatic symptoms such as poor sleep, low libido and reduced appetite tended to worsen early on, before stabilising around six weeks.
These effects are often considered side effects of SSRIs, but they can also be symptoms of depression, which complicates interpretation of their impact.
The findings also confirmed that all symptoms of anxiety began to improve at around two weeks of treatment.
The researchers concluded that antidepressants may act more rapidly on some symptoms of depression than had previously been suggested using a single summary score of symptoms.
Depression has ‘a constellation of symptoms’
According to lead author Dr Giulia Piazza, a research fellow within UCL Psychiatry, the new study shows a more complex picture of sertraline’s effects on the different symptoms of depression and highlights the importance of looking at individual symptoms rather than grouping them together.
‘Instead of thinking of depression and anxiety as each being a single, uniform condition, network analysis considers that they’re each a constellation of symptoms that can appear in different combinations for different people,’ she said.
Co-author Professor Glyn Lewis, professor of epidemiological psychiatry at UCL, who led the original PANDA trial, said: ‘Our findings provide robust evidence that continues to support the prescription of sertraline for people experiencing depressive and anxiety symptoms.
‘These findings will help patients and clinicians to make more informed decisions about treatment.’
Co-senior author Professor Jean-Baptiste Pingault, professor of developmental psychopathology and genetics at UCL, added: ‘We found that the beneficial effects of sertraline can be detected very early on, as soon as two weeks after people start taking the antidepressant.
‘Beyond this study, our results highlight the importance of considering symptom-level effects when developing novel drugs and evaluating existing drugs in psychiatry, and how this can help us to understand how these drugs work and how they can help patients.’
