22q11 deletion syndrome -- mental health in a life perspective
We talk to Lena Wallin about her research on 22q11 deletion syndrome
This month’s edition of Researcher’s Corner focuses on mental health in 22q11 deletion syndrome (22q11ds). Lena Wallin specialises in child and adolescent psychiatry and is currently a PhD student at the GNC. She is also clinically active in psychiatric services, working primarily with children and adolescents with bipolar or psychotic syndromes, obsessive-compulsive disorders, tics and selective mutism. Lena’s PhD project is titled “Mental health in 22q11-deletion syndrome from childhood to adult: a prospective longitudinal study of 90 individuals”.
What drew you to research? What are some of your main interests and how did you end up studying this issue specifically?
Ever since medical school I have always had a drive to delve deeper into my work – to really study and learn more about the field I am in. Not just because it is clinically useful, but because it makes my job more exciting and interesting as well. I love seeing such a clear connection between my research and the kind of clinical work I do every day; to reap the rewards of what I learn on a daily basis. I have been very interested in bipolar and psychotic syndromes for a long time, and through these conditions I eventually stumbled upon 22q11ds. When I heard that the GNC was planning on performing a follow-up study, looking specifically at mental health in adults with 22q11ds, I seized the opportunity right away. As a child and adolescent psychiatrist, getting the chance to observe how individuals develop into adulthood is especially valuable.
How did this project come about? What are you researching?
22q11ds is an inborn genetic disease afflicting around 1 in 4000 people, i.e. roughly 2000 Swedes – although these are conservative estimates, as there are likely quite a few unreported cases. 22q11ds usually affects several different organs. Underdeveloped thymus or parathyroid gland, along with heart and palate malformations are the most common issues. Effects on the brain often manifest later in life as varying degrees of cognitive difficulties and psychiatric conditions.
Symptoms typically include inborn heart problems, infections, feeding difficulties, speech and language difficulties, developmental delays and social interaction difficulties. Symptoms range from mild to severe. Brain-related effects include cognitive deficits and behavioural problems as well as psychiatric and neuropsychiatric symptoms.
The few long-term follow-ups that have been made show increased prevalence of autism, ADHD, anxiety syndrome, affective syndromes and schizophrenia/psychotic syndromes. 22q11ds is considered to be the strongest molecular genetic risk factor for psychosis. The risk of psychosis is 20-25 times higher than in the general population and 10 times higher than for other developmentally delayed groups.
How is the study structured?
We are planning on inviting people with the syndrome who have previously participated in a study at the GNC (Niklasson et al 2008) and are now at least 18 years old, i.e. about 90 of the 100 original participants. The participants are interviewed, asked to fill out self-scoring questionnaires and subjected to neuropsychological testing, eye movement tracking and medical examination. We will also run blood tests for genetic analysis and amino acid analysis. Parents are interviewed and asked to fill out questionnaires about their child’s development. Professor Eva Billstedt and Ingrid Vinsa are two of many people contributing to the study.
What is the purpose of the study?
Besides investigating and following up prevalence of neuropsychiatric symptoms and learning difficulties, we are also looking at prevalence and type of psychiatric conditions as well as how these develop over time. We are examining whether individuals with 22q11ds and comorbidity with ADHD, autism or intellectual disability are at greater risk of being afflicted with psychosis or other psychiatric illnesses. We are running blood tests for analysis of genetic markers and/or specific amino acid abnormalities associated with development of certain psychiatric and neuropsychiatric symptoms. We are also looking to systematically assess the participants’ quality of life.
Do you have any preliminary results?
The results indicate an increased prevalence of psychotic symptoms (approximately the same incidence indicated in previous studies). The one potential difference is that a rather large proportion of those with psychotic symptoms had them in conjunction with depression or high strain and stress. We can also see an increased prevalence of other psychiatric syndromes, both affective and anxiety disorders. Even though psychiatric symptoms are more common, the large majority of participants are neither in contact with nor regularly followed up by psychiatric services or other health care services.
What is the goal of your follow-up study? What clinical and practical significance might your research lead to in practice?
Learning more about the spectrum of cognitive, behavioural, neuropsychiatric and psychiatric symptoms as well as quality of life among individuals with 22q11ds will provide a larger knowledge base from which to build improved diagnostics and care. Increased knowledge about symptom development over time and identification of genetic risk factors can improve the chances of early diagnosis and treatment, which in turn might potentially improve the outcome in cases where e.g. psychosis or schizophrenia are involved.
Finally, identification of risk factors in 22q11ds can help us understand the genetic basis of behaviours and severe psychiatric disorders like schizophrenia and bipolar disorder.