Statins are among the most prescribed medications worldwide, useful for preventing and treating heart and metabolic diseases. However, they also have anti-inflammatory effects, which make them interesting candidates for the treatment of depression, as this mental disorder has been linked to excessive inflammation.
In this new study, The effects of statin monotherapy on depressive symptoms: A systematic review and meta-analysis, researchers pooled data from fourteen randomised controlled trials, which compared a statin given alone against placebo (a "dummy tablet"). A total of 2,712 people who were affected by depressive symptoms were involved in these trials. In this analysis, however, statins did not seem to make any difference in terms of improving or indeed worsening depressive symptoms.
A previous study, Statins for major depressive disorder: A systematic review and meta-analysis of randomized controlled trials, had shown promising evidence that statins, given along with antidepressants, may help in reducing depressive symptoms in patients who had been formally diagnosed with depression. However, it was still unclear whether statins could improve depressive symptoms regardless of a concurrent use of antidepressant medications.
Taken together, these findings suggest that statins do not decrease milder depressive symptoms on their own. However, statins plus antidepressants, compared to an antidepressant alone, appear to improve depression in patients who are most affected by it.
Dr Riccardo De Giorgi, study author and Wellcome Trust Doctoral Training Fellow, University of Oxford, said:
'Our "null findings" are important because they suggest that statins, some very commonly prescribed drugs, do not change mood in the general population – in other words, they can be considered quite safe. According to our previous study, statins might improve depression in people diagnosed with this disorder, but only when given in addition to an antidepressant. Larger studies are needed to confirm the latest evidence, but overall, our results are significant because they suggest that future clinical trials should focus on this add-on use of statins and antidepressants, compared to statins alone, for the treatment of depression.'
Read the full study, The effects of statin monotherapy on depressive symptoms: A systematic review and meta-analysis, published in Journal of Affective Disorders.