A number of meta-analyses have been conducted with regard to differences between antidepressant drugs and placebo. It is possible to criticise the choice of methodology in all such studies. We refer to two studies which are regarded as being of central importance. There are meta-analyses with more positive or more negative results when compared to placebo than the two we mentioned; and there are meta-analyses which show no advantages at all for antidepressants when compared to placebo (1).
The «Perspectives» format has space restrictions, which means that not all aspects of the topic of antidepressant drugs can be included. Effects of different forms of therapy for depression and drug alternatives to antidepressants are examples of this. Neither did we discuss in our «Perspectives» article the frequent occurrence of somatic side-effects of antidepressants, for example sexual dysfunction. The same applies to residual symptoms and reduced quality of life for depressed patients who are assessed as having a clinical effect from antidepressant drugs. New data indicate that this is a significant clinical problem – up to 60 % of the patients are described as having a condition of this kind (2).
In studies of the long-term use of antidepressant drugs, fewer relapses are reported in patients who continue with their medication unchanged compared with those who switch from an active drug to a placebo. However, this difference is restricted to the first six months. After that there is no difference. The data indicate that the positive results reported in favour of long-term use of antidepressants can in large part be attributed to the development of primary tolerance and withdrawal symptoms following discontinuation in the group of patients who switch to placebo (3). Longer exposure to antidepressant drugs prior to randomisation to placebo entails an increased risk of relapse (4).
Our «Perspectives» article concluded by saying that we need drug information from independent sources. This type of information will change the prescribing practice. We pointed out that the pharmaceutical industry engages in uncritical marketing – side effects are downplayed and critical arguments are not taken seriously. The pharmaceutical industry’s response to the «Perspectives» article confirms rather than refutes our conclusion.
