Peter Lilliengren Universitetslektor, docent

Om mig

Jag är docent i klinisk psykologi, leg psykolog, leg psykoterapeut och handledarutbildad. Har ca 10 års yrkeserfarenhet som psykolog inom vuxenpsykiatrin. Doktorerade 2014 vid Stockholms Universitet med en avhandling som fokuserade på verksamma mekanismer i psykoanalytisk terapi med unga vuxna samt terapirelationen ur ett anknytningsteoretiskt perspektiv.

Arbetar idag 60% på Psykologiska Institutionen som lektor och resten av tiden i privat verksamhet med främst psykoterapi och handledning. Har ett generellt intresse för utfall- och processforskning inom psykodynamisk psykoterapi samt ett särskit intresse för s.k. affektfokuserade psykodynamiska korttidsterapier. Har genomgått terapeut- och handledarutbildning i Intensive Short-Term Dynamic Psychotherapy (ISTDP) vilket är den specifika psykodynamiska terapimodell jag främst arbetar med idag.

Jag har även ett allmänt intresse för olika försök till integration och eklekticism på psykoterapiområdet samt forskning kring verksamma faktorer inom olika terapiinriktningar. Min psykologexamensuppsats handlade om psykoterapiintegration ur ett psykodynamiskt perspektiv och för den erhöll jag andra pris i psykologförbundets uppsatstävling 2002.

Jag undervisar främst på psykoterapeutprogrammet med PDT-inriktning och har bl a kursansvar för kurserna "Psykoterapi under handledning", "Komplexa fall" samt "Introduktionskurs". Undervisar även en del på psykologprogrammet samt handleder uppsatser på olika nivåer.

Mitt huvudsakliga forskningsintresse är utfall och process i olika former av psykodynamiska psykoterapier samt betydelsen av gemensamma faktorer i psykoterapi mer generellt. Jag har även ett särksilt intresse för känslors betydelse i psykoterapi och är bl a projektledare för ett forskningsprojekt där vi undersöker effekten av känslofokuserade interventioner vid s.k. "medicinskt oförklarade symptom".

Du kan se mina publikationer i DiVA nedan eller på min fullständiga publiaktionslista här. pdf, 157.4 kB.


  • Anxiety pathways in ISTDP

    Artikel
    2025. Daniel Maroti, Emelie Hasselgren, Viktor Vallhagen, Johnny Hellgren, Peter Lilliengren, Robert Johansson.

    Although case studies support the notion of three anxiety pathways in Intensive Short-Term Dynamic Psychotherapy (ISTDP), empirical research remains scarce, highlighting the need to investigate how somatic symptoms cluster in line with ISTDP’s anxiety pathway theory using validated measures. This study therefore explored the clustering of self-reported somatic symptoms in 550 patients with persistent physical symptoms (PPS) from three previous randomized controlled trials, examining their potential alignment with the theory of unconscious anxiety and its discharge pathways, as proposed in ISTDP. Using the Patient Health Questionnaire-15 (PHQ-15), an exploratory factor analysis identified three symptom clusters—musculoskeletal, gastrointestinal, and cardiopulmonary—that together explained 40.1% of the variance. This three-factor structure, validated through confirmatory factor analysis, partially aligned with ISTDP’s conceptual anxiety pathways, though limitations were noted in capturing cognitive-perceptual disturbances. These findings suggest that self-reported symptom assessment can complement clinician-led methods in identifying anxiety-related symptom clusters, warranting further development of self-report tools within psychodynamic assessment frameworks.

    Läs mer om Anxiety pathways in ISTDP
  • A Randomized Cross-Over Trial Comparing Life Stress Interview Versus Basic Assessment of Psychiatric Symptoms for Patients With Persistent Physical Symptoms

    Artikel
    2025. Daniel Maroti, Malin Ljungdahl, Helena Petersen, Mattias Rööst, Fredrik Falkenström, Peter Lilliengren.

    Objective: This randomized cross-over trial aimed to compare the effects of a one-session emotion-focused intervention, the Life Stress Interview (LSI), with a Basic Assessment of Psychiatric Symptoms (BAS) condition for patients with persistent physical symptoms (PPS).Methods: One hundred eighty-nine participants (n=189), predominantly middle-aged females with high psychiatric comorbidity and persistent somatic symptoms, were randomly assigned to receive both LSI and BAS in varying order. Symptom change over time and interaction effects were analyzed using linear mixed models.Results: Both conditions led to significant reductions in somatic symptoms (PHQ-15; B=−0.51, 95% CI=−0.76, −0.26) and psychiatric distress over time, but no significant differences between LSI and BAS were observed. However, significant Sequence×Treatment interaction effects indicated that administering LSI first rather than second resulted in a steeper decline in somatic symptoms (PHQ-15: B=0.57, 95% CI=0.15, 1.00) and post-traumatic symptoms (PCL-5: B=1.85, 95% CI=0.05, 3.64), whereas the timing of BAS had little effect on outcome.Conclusion: Our finding that the LSI does not yield more symptom reduction in patients with PPS than a comparison diagnostic interview raises questions about the LSI’s unique value, although the observed sequence effect suggests that the LSI may enhance symptom improvement when followed by a psychiatric assessment. Moreover, both brief interventions appear to contribute to symptom reduction. A limitation is that prior psychotherapy experience may have reduced the LSI’s impact, and emotional processing during interviews was not assessed. Further research should explore how LSI can be integrated with other interventions to meet the diverse needs of patients with PPS.

    Läs mer om A Randomized Cross-Over Trial Comparing Life Stress Interview Versus Basic Assessment of Psychiatric Symptoms for Patients With Persistent Physical Symptoms
  • Interpersonal problems as a predictor of treatment outcome in adult depression

    Recension
    2025. Juan Martín Gómez Penedo, Manuel Meglio, Christoph Flückiger, Frederik J. Wienicke, Jasmijn Breunese, Marco Menchetti, Paola Rucci, Robert Johansson, Joel M. Town, Allan A. Abbass, Peter Lilliengren, R. Michael Bagby, Lena C. Quilty, Lotte H.J.M. Lemmens, Suzanne C. van Bronswijk, Michael Barkham, William B. Stiles, Gillian E. Hardy, Peter Fonagy, Patrick Luyten, Matthew P. Constantinou, Jacques P. Barber, Kevin S. McCarthy, Nili Solomonov, Anthony S. Joyce, Pim Cuijpers, Ellen Driessen.

    Objectives: Interpersonal problems are a fundamental feature of depression, but study-level meta-analyses of their association with treatment outcome have been limited by heterogeneity in primary studies' analyses and reported results. We conducted a pre-registered individual participant data meta-analysis (IPD-MA) to examine this relationship for adult depression. This meta-analytic strategy can reduce variability by standardizing data analysis across primary studies. Methods: We included studies examining the efficacy of five treatments for adult depression and assessing interpersonal problems at baseline. One-stage IPD-MA was conducted with three-level mixed models to determine whether baseline overall interpersonal distress, agency, and communion predicted depressive symptom level at post-treatment, 12-month, and 24-month follow-up. The moderating effect of treatment type was also investigated. Results: Ten studies (including n = 1282 participants) met inclusion criteria. Only overall interpersonal distress was negatively related with outcomes at post-treatment (γ = 0.11, CI95[0.06, 0.16], r = 0.11), 12-month follow-up (γ = 0.17, CI95[0.08, 0.25], r = 0.17), and 24-month follow-up (γ = 0.16, CI95[0.05, 0.26], r = 0.16), indicative of smaller effect sizes. The agency and communion dimensions were not significantly related to outcome. Treatment type did not significantly moderate interpersonal distress-outcome associations. Discussion: Results show a small association between patient baseline overall interpersonal distress and subsequent depression treatment outcome in brief treatments for depression. Further studies might require to account for therapist effects.

    Läs mer om Interpersonal problems as a predictor of treatment outcome in adult depression
  • Psychodynamic therapy can be adapted to and implemented in non-western cultures – a comment on the WHO treatment guideline for mental disorders

    Artikel
    2025. Falk Leichsenring, Allan Abbass, Peter Fonagy, Kenneth Levy, Peter Lilliengren, Patrick Luyten, Nick Midgley, Barbara Milrod.

    The WHO recently updated the guidelines for treating mental health conditions in low- and middle-income countries, emphasizing evidence-based manual-guided psychotherapeutic treatments. As a limitation, these recommendations predominantly endorse cognitive-behavior therapy for both adults and young people. In a comment, we emphasized that the WHO overlooked the significant evidence supporting other therapeutic approaches, including but not limited to psychodynamic therapy. The WHO responded to our comment in a reply by Carswell and colleagues. However, several statements made by the authors are debatable. In this short communication, we critically address these statements, showing that they are not tenable. As a conclusion we emphasize that it is necessary to embrace a broader array of empirical supported therapeutic methods to elevate the overall quality and efficacy of global mental health care. High-quality psychotherapy research in low- and middle-income countries is required, focusing not only on the narrow area of symptoms, but transdiagnostically on general psychopathology and psychosocial functioning, which are areas addressed in psychodynamic therapy.

    Läs mer om Psychodynamic therapy can be adapted to and implemented in non-western cultures – a comment on the WHO treatment guideline for mental disorders
  • The Efficacy of Experiential Dynamic Therapies

    Recension
    2025. Peter Lilliengren, Jakob Mechler, Karin Lindqvist, Daniel Maroti, Robert Johansson.

    There is a growing interest in clinical interventions targeting emotion regulation difficulties across mental health conditions. Experiential dynamic therapies (EDTs) are transdiagnostic, affect-focused, short-term psychodynamic therapy models that emphasize in-session emotional processing. This review provides a 10-year update on the efficacy of EDTs for mood, anxiety, personality and somatic symptom disorders in adults and children/adolescents. A comprehensive search identified 57 randomized controlled trials (n = 4330) conducted in Western (k = 38; n = 3178) and non-Western countries (k = 19; n = 1152) between 1978 and 2024. Random-effects meta-analyses on primary outcomes indicated large, significant effects for EDTs compared to inactive controls at post-treatment (Hedge's g = −0.96; k = 41) and follow-up (g = −1.11; k = 20). Compared to active controls, effects were small and non-significant post-treatment (g = −0.17; k = 27) but became significant at follow-up (g = −0.40; k = 19), suggesting a potential modest long-term advantage of EDTs. Despite substantial heterogeneity (I2 > 75%), results remained robust in sensitivity analyses. Moderator analyses revealed few significant findings, indicating relative consistency across diagnostic groups, treatment formats and active comparators. Non-Western and lower quality studies reported larger effects compared to inactive, but not active, controls. While cautious interpretation is warranted due to unexplained heterogeneity, findings support EDTs as efficacious transdiagnostic interventions for emotional disorders, with sustained benefits over time. Future research should prioritize large-scale, methodologically rigorous trials that explore mechanisms of change, optimize treatment delivery and identify moderators of long-term outcomes.

    Läs mer om The Efficacy of Experiential Dynamic Therapies

ERiCA

Inom ERiCA-projektet har vi utvecklat en internetförmedlad psykodynamisk terapi (IPDT) för ungdomar med depression. Behandlingen har prövats i två publicerade forskningsstudier med goda resultat. En tredje studie avslutades i december 2024.