Change Mechanisms in Brief Interpersonal Psychotherapy for Perinatal Depression: A Qualitative Study

Background and Purpose: Interpersonal psychotherapy (IPT; 16 acute sessions) and its brief version (IPT-B; 8 acute sessions) have received support as an effective intervention to treat acute depression, antenatal and postpartum depression, and prevent depressive relapse through maintenance sessions. Despite its effectiveness, as demonstrated in numerous studies, it is not clear how interpersonal psychotherapy alleviates depression. Lipsitz and Markowitz (2013) proposed four mechanisms of change derived from IPT’s interpersonal model: 1) enhancing social support, 2) decreasing interpersonal stress, 3) facilitating emotional processing, and 4) improving interpersonal skills.

The present study contributes to the literature by exploring how women who received IPT and women who received usual care for depression in the perinatal period evaluated their respective experiences, after the trial was completed. We considered what they viewed as change mechanisms, how barriers to care were overcome, and how they were feeling at the end compared to at the beginning of the trial.

Methods: The MOMCare Study recruited a sample of 168 women from clinics in the Public Health Seattle-King County system, who were suffering from depression and/or dysthymia. The women were randomized to receive the study intervention (IPT and/or medications), or usual care. The final outcome assessment occurred at 18 months post-baseline. After the randomized control trial (RCT) was completed, a qualitative study was conducted with 16 participants from the RCT. The sample was evenly split on intervention group, depression improvement at 12 months, and co-morbid PTSD status. The average age was 34, and 69% were non-Hispanic white. Interviews were conducted by phone, and included semi-structured open-ended questions and probes, developed by the research team through an iterative process. Questions elicited participants’ experiences with depression treatment, evaluation of treatment, and assessment of their change in mood. Interviews were transcribed, and coded using an integrative approach, applying principles of inductive reasoning and predetermined, theoretically-derived codes (based on the four identified mechanisms).

Findings: Women in the study intervention reported positive feelings about their therapists and overall were very satisfied with the program. Compared with the usual care group, they expressed more success in identifying and expressing emotions, being able to reflect on emotions, and being able to regulate emotions. They reported dealing with an interpersonal problem or reducing interpersonal stress, and improving interpersonal skills. Differences were not apparent for improved social support or utilization of case management. Several women in the usual care group reported difficulties accessing mental health treatment and frustrations with their care; women in the study intervention praised the program for “not giving up on them”, “being flexible with their schedules”, and for “helping them make it through such a difficult time”.

Conclusion and Implications: Findings provide support for the role of IPT in decreasing interpersonal stress, facilitating emotional processing, and improving interpersonal skills resulting in alleviation of depression symptoms. Enhancement of social supports was equally endorsed by those in the intervention and control groups. IPT was well-received by study participants, and results support the value of interpersonal psychotherapy for high risk pregnant and parenting women who are depressed.