67 - Recurrent depression

Recurrent depression

Depression and anxiety disorders CHAPTER 3 Antidepressant prophylaxis After first episode A single episode of depression should be treated for at least 6–9 months after full remission.1 If antidepressant therapy is stopped immediately on recovery, 50% of patients experience a return of depressive symptoms within 3–6 months.1 A landmark study of fluoxetine maintenance2 demonstrated that stopping successful treatment at 12 weeks produced the highest relapse rate, followed by withdrawal at 26 weeks, and then withdrawal at 50 weeks (at which point placebo and active treatment did not differ in respect to relapse risk). Another trial suggested that withdrawal should only be attempted when patients had been free of significant symptoms for 16–20 weeks.3 Even non-­continuous use of antidepressants during the first 6 months of treatment predicts higher rates of relapse.4 Recurrent depression Major depressive disorder is unremitting in 15% of cases and recurrent in 35%. About 50% of those with a first-­onset episode recover and have no further episodes when followed for over 20 years.5 Many factors are known to increase the risk of recurrence, including a family history of depression, recurrent dysthymia, concurrent non-­affective psychiatric illness, female gender, long episode duration, degree of treatment resistance,6 chronic medical illness and social factors (e.g. lack of confiding relationships and psychosocial stressors). Some prescription drugs may precipitate depression.6,7 Antidepressants are generally effective in the post-­acute maintenance phase  – the 6 months after remission.8 Longer-­term outcomes have also been examined. Figure 3.4 outlines the risk of recurrence for patients who have multiple episodes of depression. Those recruited to the study had already experienced at least three episodes of depression, with 3 years or less between episodes.9,10 A meta-­analysis of antidepressant continuation studies11 concluded that continuing treatment with antidepressants reduces the odds of depressive relapse by around two-­thirds 80 40 % of patients remaining well 0 6 24 Time (months) 48 Active drug Placebo after 3 years Placebo Figure 3.4  The risk of recurrence in patients who have several episodes of depression. Patients had experienced at least three episodes of depression with 3 years or fewer between episodes.