Researchers have developed a blood test which can help doctors choose the best drug to treat patients with depression, according to a report published in the International Journal of Neuropsychopharmacology.
The study, which was carried out at King’s College London, involved 140 people with depression. It was found that high levels of inflammation (which is one of the ways the body responds to stress) can interfere with the ability of antidepressants to increase serotonin levels in the brain.
The blood test looks for signs of inflammation, indicated by the presence of compounds called macrophage migration inhibitory factor and interleukin-1 beta.
The researchers found that participants who tested positive for inflammation were unlikely to respond to conventional SSRIs (selective serotonin re-uptake inhibitors) and tricyclic antidepressants.
The study’s lead researcher, Professor Carmine Pariante, said: ‘About a third of patients might have these inflammatory markers and they would be people we might encourage to go on more aggressive treatment.
‘We would not want to go in prescribing too much medicine if it’s not necessary, but we would want to escalate people sooner rather than later if they need it.’
The researchers believe that the new test will allow health professionals to more accurately prescribe medication to mental health patients. Currently, patients do not remain on the first antidepressant they are prescribed in about half of all cases.
Depression is unfortunately one of the currencies of modern general practice, and GPs have two main tools at their disposal — medication and counselling. The waiting times for counselling can unfortunately be very long, so many have to resort to prescribing antidepressant medication, and there are many options available on the market.
Half of the time the first choice of treatment fails to work, causing frustration for both doctor and patient, but also increasing the risk of worsening depression and self-harm in that time.
Anything that could help doctors identify which treatment would best suit a depressed patient would not only be revolutionary but also have significant implications for speed of recovery and costs to the NHS.
This blood test — admittedly only carried out on a very small number of volunteers — does appear to show real promise and raises the longer-term hope that a simple test could be available in a few years to allow the best treatment to be started straight away.
As always, these results now have to be replicated with large patient numbers but the science would suggest that this may well occur, opening the door to individualised treatment in depressed people. An interesting, highly important and significant test to help our depressed patients may now be just around the corner.
Research score: 4/5