(298) A nationwide study of psychotherapy treatment at Danish psychiatric clinics

Background: Psychotherapy holds few side effects and is first-line treatment for depression, anxiety and obsessive compulsive disorder (OCD).

Objectives: We aimed to quantify use of psychotherapy and characterize patients receiving therapy at Danish psychiatric hospital clinics.

Methods: Using the Danish National Patient Register (DNPR), we included all individuals registered with a first ever psychotherapy procedure code during 2010-2021, limiting to individuals born after 1969. The DNPR also provided information on recorded psychiatric disorder diagnoses. We calculated annual incidence rates of psychotherapy and characterized incident users of psychotherapy according to psychiatric disorder diagnosis and filling of psychotropic prescriptions six months prior to therapy initiation. We also determined type of therapy (individual, group, or family) and median number of sessions within the first year after initiation. All analyses were stratified by sex and age groups (3-17 vs. ≥18 years).

Results: The incidence of psychotherapy treatment increased in Denmark from 2010 to 2015, whereafter it stabilized for youths and declined for adults. Incidence rates were almost twice as high for females as for males in both age groups. Anxiety disorders including OCD were the most common psychiatric disorders among users of psychotherapy, constituting approximately 30% of all diagnoses for youths and 40% for adults in 2020. Almost three out of four children and adolescents were psychotropic-naïve when initiating psychotherapy in 2020, whereas that was the case for less than half of adults (45-47%).
Individual psychotherapy was the most common type of therapy, constituting 60% and 65% of therapy for girls and boys, respectively, and 66% and 74% for women and men, respectively. Family therapy was used for 24% of girls and 20% of boys but rarely in adult psychiatry (≤1%). The median number of individual therapy sessions within the first year was four sessions for adults (Interquartile range (IQR) 1-10), three for boys (IQR 1-8) and five for girls (IQR 2-9).

Conclusions: Use of psychotherapy in Danish psychiatric clinics increased at the beginning of the study period but decreased from 2016 onwards for adults and remained stable for youths. Anxiety disorders and OCD were the most common disorders in patients offered psychotherapy, which reflects the solid evidence base of the efficacy of psychotherapy for these conditions. Although frequent interventions are the most important predictor of effective psychotherapy treatment, most patients had only 3-5 sessions within the first year.