fbpx Depression: predicting therapeutic response | Progress In Mind

Depression: predicting therapeutic response

Professor Yamawaki describes predicting therapeutic response

Efforts to personalise choice of initial therapy and any adjustments needed in cases of inadequate response are highly worthwhile. But we are at an early stage in our efforts to find biomarkers that distinguish likely responders from those less likely to benefit from a particular treatment.

Might longer be better?

Switching to an antidepressant with a different mechanism of action is often suggested when a patient does not respond adequately to one agent even after six to eight weeks of treatment. Work from the multinational Group for the Study of Resistant Depression (GSRD) challenged this view, according to Siegfried Kasper, Austria. It may be that staying with an antidepressant with the same mechanism of action for a longer period is more beneficial than switching.

Staying with an antidepressant with the same mechanism of action for a longer period is more beneficial than switching

More recently, the GSRD has been trying to develop a model that distinguishes between patients who do not respond adequately to a 6-8 week trial of one agent; treatment resistant depression, which is defined as non-response to adequate trial of two or more agents of different classes; and “chronic non-response”, the term used to categorize patients who have not been helped despite treatment with several antidepressants for more than twelve months.

Allelic combinations may predict response

A decade of work suggested that specific clinical features and individual single nucleotide polymorphisms (SNPs) provided little guidance to clinical outcome. This prompted the investigators to look at the interactions between clinical variables and SNPs in the hope that a pattern of features might prove more helpful. 

They are currently suggesting that the absence of melancholia plus a set of three SNPs – the allelic combination of GG-GG-TT for rs6265, rs7430 and rs6313 of the BDNF, PPP3CC and HTR2A genes –might be such a combination. Around 62% of patients with these features showed a relevant HAM-D while only 34% of the study population as a whole responded to this extent.

Such studies, therefore, promise increasing ability to distinguish patients according to likelihood of response, but the large amount of data generated by this and other projects means that machine learning techniques are needed to handle it; and the output will be complex statistical algorithms.

Studies promise increasing ability to distinguish patients according to likelihood of response

Despite all we have learned about the variable aetiology and clinical presentation of depression, deciding between psychotherapy and pharmacotherapy, and prescribing a specific anti-depressant in an individual patient, largely remain a process of trial and error.

Imaging biomarkers for drug responses

Several fMRI studies suggested that greater baseline activity in the anterior cingulate cortex (ACC) and medial prefrontal cortex (mPFC) is associated with better response to SSRIs

There are still no widely accepted biomarkers to assist in making diagnosis more precise, nor in aiding choice of treatment in specific cases. So it perhaps not surprising that we seem stuck with response rates to drug treatment of 50% or less. Can neuroimaging, and functional MRI (fMRI) in particular, make a helpful contribution in this setting?, asked Shigeto  Yawamaki, Japan.

Using tasks requiring response to emotional stimuli, several fMRI studies in patients with depression have suggested that greater baseline activity in the anterior cingulate cortex (ACC) and medial prefrontal cortex (mPFC) is associated with better response to SSRIs. In contrast, greater baseline activity in the amygdala seemed to predict better response to CBT.

Attention has recently focused on resting state fMRI as a means of investigating potential, clinically  significant differences in brain circuitry underlying processing of reward and regulation of emotion. There is some evidence, for example, that treatment with SSRIs increases resting state connectivity between subcortical areas and the ACC. But, Professor Yawamaki cautioned, it is unlikely that any single clinical or imaging marker will adequately predict likelihood of response to specific kinds of intervention or classes of antidepressant.

You are leaving Progress in Mind
Le informazioni contenute nel nuovo sito prescelto possono non essere conformi al D.Ivo 219/06 che regola la pubblicità dei medicinali per uso umano e le opinioni espresse non riflettono necessariamente le posizioni dell’azienda, non sono da essa avvallate.
Accesso riservato a Operatori Sanitari
Per accedere si prega di registrarsi o, in caso sia già stato fatto, di autenticarsi
L’accesso a Progress in Mind Italia è consentito unicamente ai Professionisti Sanitari. I contenuti di questo sito sono prodotti da un team dedicato di Professionisti Sanitari e medical writer il cui obiettivo è presentare le novità scientifiche più recenti insieme ad opinioni di esperti ed approfondimenti in ambito psichiatrico e neurologico. Per poter accedere al sito è, quindi, necessario registrarsi e fornire alcuni dati così da poter verificare che l‘utente sia un Professionista Sanitario.
ACCESSO RISERVATO A OPERATORI SANITARI AUTORIZZATI
Per accedere alla pagina si prega di registrarsi o, in caso sia già stato fatto, di autenticarsi. La pagina per la quale sta richiedendo l'accesso ospita materiale formativo comunque attinente all'impiego di medicinali prodotti o commercializzati da Lundbeck. Con riferimento al Decreto Legislativo n.219 del 24 aprile 2006 e s.m.i., art. 119, art. 121 comma 1 e art. 124 commi 4 e 8, Lundbeck limita l'accesso ai contenuti presenti nella pagina PIM Academy a medici specialisti e farmacisti ospedalieri.
Hello
Please confirm your email
We have just sent you an email, with a confirmation link.
Before you can gain full access - you need to confirm your email.
The information on this site is exclusively intented for health care professionals.
All the information included in the Website is related to products of the local market and, therefore, directed to health professionals legally authorized to prescribe or dispense medications with professional practice. The technical information of the drugs is provided merely informative, being the responsibility of the professionals authorized to prescribe drugs and decide, in each concrete case, the most appropriate treatment to the needs of the patient.
Congress
Register for access to Progress in Mind in your country