Associate Professor Dee Mangin
“There is a real need for evidence about whether long-term use of antidepressants is effective for those with milder depression who are treated in primary care.”
To prescribe or not to prescribe. That is the question faced daily by GPs treating those with depression.
Up to 90 per cent of patients with depression are seen in primarycare settings and GPs, commonly, put patients who have had a number of episodes of depression on a “maintenance therapy” of long-term antidepressant use to prevent a relapse.
But, according to University of Otago, Christchurch, Associate Professor Dee Mangin, there is a lack of evidence about whether this approach actually works.
“No doctor wants a patient to have a recurrence of depression, but they also do not want to keep prescribing medication if it is not proven to reduce the frequency of recurrence,” Mangin says.
“There is a real need for evidence about whether long-term use of antidepressants is effective for those with milder depression who are treated in primary care. Doctors and patients can often be in a real dilemma and need more information to make choices about medication.”
Mangin and her team are trying to ease that dilemma. They are halfway through a research project involving 330 patients from Christchurch, Auckland and Wellington who have taken the most commonly-prescribed antidepressant, Fluoxetine, long-term to prevent depression recurrence.
Half of patients are continuing to take the antidepressant, while half are being weaned off to placebo. They are being followed for 18 months to monitor recurrence of symptoms of depression, side effects and general social and occupational functioning. Patients are also recording impressions of their own progress – a novel aspect for this type of study.
Mangin says withdrawal symptoms are common when stopping antidepressants, particularly selective serotonin re-uptake inhibitors (SSRIs) such as Fluoxetine.
These withdrawal symptoms are often very similar to the recurrence of depression and patients often, mistakenly, think stopping their medication has caused a relapse.
Mangin's study will look at which patients experience withdrawal symptoms and which respond best to stopping their medication. The research will have obvious and immediate implications for doctors and their patients when it is completed next year.
Mangin says prescription of drugs for mood is becoming more prevalent worldwide and, increasingly, clinicians are prescribing antidepressants and other psychotropic drugs long-term. She believes there is a need for a great deal more information about the implications of this long-term use. This study will provide results which can immediately be used in clinical practice, both in New Zealand and potentially elsewhere.
Funding
- Health Research Council
- University of Otago Research Grant
- Canterbury Medical Research Foundation