The chicken or the egg – PTSD or MDD which to treat first

Clinicians are often faced with comorbid presentations with PTSD. Grinage (2003) reported that at least one additional psychiatric disorder is present in 88.3 percent of men and 79.0 percent of women who have a history of PTSD.  Recent research by at team from Flinders University, Angelakis and colleagues (2020) helps clinicians with the decision-making process when faced with a client suffering from PTSD and Major Depressive Disorder.  The classic chicken or the egg dilemma.

Angelakis and colleagues (2020) found that Cognitive Processing Therapy (CPT) followed by Behavioural Activation Therapy (BA) had better outcomes in terms of larger effect sizes and loss of diagnoses compared to CPT alone and compared to Behavioural Activation Therapy followed by CPT.  They reported that at 6-month follow-up greater numbers of the CPT followed by BA group were estimated to have achieved good end-state for remission of both PTSD and depression compared to the two other groups. Angelakis et. al. (2020) cautioned that their sample size was modest.

As well as indicating the order of treatment for co-morbid presentations Angelakis and colleague’s (2020) paper also highlights the importance of Behavioural Activation Therapy in the treatment of Major Depressive Disorder. This is pertinent for clinicians who may be treating clients with cognitive therapies (such as CPT); to remember the importance of behavioural components in therapy. Similarly, in the age of telehealth and COVID-19 where therapy can be focussed on the cognitive components of a client’s difficulties behavioural activation may slip off the agenda.



Angelakis, S., Weber, N., & Nixon, R. (2020). Comorbid posttraumatic stress disorder and major depressive disorder: The usefulness of a sequential treatment approach within a randomised design. Journal of anxiety disorders76, 102324.

Grinage B. D. (2003). Diagnosis and management of post-traumatic stress disorder. American family physician68(12), 2401–2408.