Largest study on hoarding symptoms

This week, our latest study on hoarding symptoms in young people was published in Plos One. In this study, we used data from the Swedish Twin Registry  on twins in 3 samples (ages 15, 18 and 20-28 years). We had access to data for more than 16 000 twins (largest sample to date) and estimated the heritability at every age and also conducted longitudinal analyses on twins with data at ages 15 and 18. Our results showed that hoarding symptoms were heritable at all ages although the heritability decreased somewhat with age. Symptoms of hoarding were also moderately stable between ages 15 and 18, and this stability was largely due to genetic factors while non-shared environmental factors had a time-specific effect.

Follow the link below to access the publication:

Doctor Jesper Enander defended his thesis!

Jesper Enander today received his PhD after successfully defending his thesis today. Congratulations Jesper!



Jesper (the tallest) surrounded by his supervisors. To the left the opponent Prof Ulrike Buhlmann being distracted by Prof Jerker Hetta from the examination board.


The examination board: Klaas Wijma, Linköping University, Jerker Hetta and Kalle Lundgren, KI.




It’s done.

Manuel Mattheisen joins our group

Our collaborator Manuel Mattheisen, Associate Professor at Århus University, is now officially affiliated to Karolinska Institutet and our group.  He studied medicine at the University in Bonn and went on to be a research follow at Harvard Medical School before moving to Denmark. We are fortunate to enjoy his deep expertise in genetical methods. Check out his quite spectacular publication list here.





Jesper Enander to defend thesis on May 5th

Jesper is about to defend his thesis titled: “Etiology, prevalence, and development of a novel treatement for body dysmorphic disorder” May 5 at 09.00 in Lecture hall H1, Alfred Nobels Allé 23, Campus Flemingsberg. Do not miss! 

His Opponent will be Professor Ulrike Buhlman, University of Münster.

Examination Board:
Associate Professor Kalle Lundgren, Karolinska Institutet, Department of Molecular Medicine and Surgery

Professor Klaas Wijma, Linköping University, Department of Clinical and Experimental Medicine

Professor Jerker Hetta, Karolinska Institutet, Department of Clinical Neuroscience

Principal Supervisor:
Associate Professor Christian Rück, Karolinska Institutet, Department of Clinical Neuroscience

Professor David Mataix-Cols, Karolinska Institutet, Department of Clinical Neuroscience

Professor Paul Lichtenstein, Karolinska Institutet, Department of Medical Epidemiology and Biostatistics

Associate Professor Brjánn Ljótsson, Karolinska Institutet, Department of Clinical Neuroscience

A strong week for CBT-treatment of pediatric OCD

It has been an intense week for those involved in the treatment of OCD in children and adolescents. Fabian Lenhard has successfully defended his thesis, congratulations Fabian! His opponent was Professor John Piacentini from University of California, Los Angeles. Professor Piacentini is an experienced clinician and researcher in pediatric OCD. Yesterday he gave a lecture on the research frontiers in this field.


Fabian and his supervisors. From left to right: Erik Andersson, Eva Serlachius, Fabian Lenhard, Christian Rück, and David Mataix-Cols

Internet-delivered CBT for adolescents with OCD

The topic of Dr. Lenhard’s thesis is Internet-delivered Cognitive Behavior Therapy for Adolescents with Obsessive-Compulsive Disorder. You can find the thesis here:

He has developed and tested the treatment in an open trial and a randomized controlled trial. Analyses on cost-effectiveness and predictors of outcome are underway.


Fabian during his dissertation

The results from both the open trial and the randomized trial indicate that internet-delivered CBT is an effective treatment for adolescents with OCD. The pre-post within-group effect sizes were large in both trials.

Link to the open trial:

Link to the randomized trial:


Main results from the open trial.


Main results from the randomized trial

Professor John Piacentini: Optimizing Outcomes for Pediatric OCD

During his visit to Sweden, Professor Piacentini talked about research that aims to optimize outcomes in pediatric OCD. After receiving CBT, around 40 % of patients are in remission. While our treatments are effective for some, we still have a long way to go in order to treat every child and adolescent with OCD. Looking into specific mechanisms of change might be a way to optimize the current treatments.


Professor Piacentini of UCLA

Some suggested mechanisms include expectations of recovery (which might be mediated by home work compliance), the ability of a therapist to push exposures, and affect labeling (”I feel scared”) rather than cognitive restructuring during exposure.

Professor Piacentini also discussed recent work on neurotransmitters that directly target the underlying brain correlates of OCD. For example, glutamate levels might serve as a possible moderator of treatment outcome. We are awaiting the results from trials that aim to change glutamate levels pre-treatment to enhance the outcomes of CBT.

Rücklab visits professor Thalia Eley & EDIT lab at King’s college, London

Thalia Eley is professor of developmental behavioural genetics at SGDP centre, Institute of psychiatry, King’s College, London. She is also head of EDIT lab where the research focuses on the genetic and environmental effects on development and treatment of anxiety and depression amongst children.

IMG_0070Christian Rück, Thalia Eley, Evelyn Andersson, Julia Boberg & Chris
Rayner outside EDIT lab.

The EDIT lab team aim to explore why anxiety and depression disorders to some extend run in the family. On one hand they do twin studies to explore how much of variation in a phenotype, i.e. anxiety disorders, could be explained by genetic variance and on the other hand they perform studies on environmental factors to explore to what extent variation could be explained by nurture.

The BioPoRT project is a part of IAPT (Increasing access to psychological treatment) in the UK. The aim of  BioPoRT is to find predictors for treatment outcome, exploring both demographic variables as well as clinical and genetic factors. The latter is called therapygenetics, a term coined by Thalia Eley a few years ago.

Additionally the team do research on information processing.

We got a tour of the actual lab by the centre laboratory manager Bernard Freeman, where the whole genome sequencing (GWAS) is being executed. He showed us DNA extracted from salmon sperm and some very high tech machinery.

IMG_0077GWAS chip

IMG_0074Bernard Freeman with the double helix

The team also run the EDIT lab blog, a great source for novel research, interesting chronicles about bringing research into daily life hazzle (such as making your baby sleep) and the challenges one could face when working as a researcher.

Much of the work done at EDIT lab is related to the genetics work done at Rücklab, although our experience and knowledge in the field is a bit more scant. We look forward to future collaborations with the EDIT lab team.