ABSTRACT
Up-to-date information on the prevalence and trends of common mental disorders is relevant to health care policy and planning, owing to the high burden associated with these disorders. In the first wave of the third Netherlands Mental Health Survey and Incidence Study (NEMESIS-3), a nationally representative sample was interviewed face-to-face from November 2019 to March 2022 (6,194 subjects; 1,576 interviewed before and 4,618 during the COVID-19 pandemic; age range: 18-75 years). A slightly modified version of the Composite International Diagnostic Interview 3.0 was used to assess DSM-IV and DSM-5 diagnoses. Trends in 12-month prevalence rates of DSM-IV mental disorders were examined by comparing these rates between NEMESIS-3 and NEMESIS-2 (6,646 subjects; age range: 18-64 years; interviewed from November 2007 to July 2009). Lifetime DSM-5 prevalence estimates in NEMESIS-3 were 28.6% for anxiety disorders, 27.6% for mood disorders, 16.7% for substance use disorders, and 3.6% for attention-deficit/hyperactivity disorder. Over the last 12 months, prevalence rates were 15.2%, 9.8%, 7.1%, and 3.2%, respectively. No differences in 12-month prevalence rates before vs. during the COVID-19 pandemic were found (26.7% pre-pandemic vs. 25.7% during the pandemic), even after controlling for differences in socio-demographic characteristics of the respondents interviewed in these two periods. This was the case for all four disorder categories. From 2007-2009 to 2019-2022, the 12-month prevalence rate of any DSM-IV disorder significantly increased from 17.4% to 26.1%. A stronger increase in prevalence was found for students, younger adults (18-34 years) and city dwellers. These data suggest that the prevalence of mental disorders has increased in the past decade, but this is not explained by the COVID-19 pandemic. The already high mental disorder risk of young adults has particularly further increased in recent years.
ABSTRACT
OBJECTIVES: NEMESIS-3 (Netherlands Mental Health Survey and Incidence Study-3) is a psychiatric epidemiological cohort study of the Dutch general population that replicates and expands on two previous NEMESIS-studies conducted in 1996-1999 and 2007-2018 respectively. The main aims of NEMESIS-3 are to provide up-to-date information on the prevalence, incidence, course and consequences of mental disorders, their risk indicators, and to study the relevant time trends. This paper gives an overview of the objectives and methods of NEMESIS-3, especially of the recently completed first wave, and describes the sample characteristics. METHODS: NEMESIS-3 is based on a multistage, stratified random sampling of individuals aged 18-75 years. Face-to-face interviews were laptop computer-assisted and held at the respondent's home. A slightly modified Composite International Diagnostic Interview (CIDI) version 3.0 was used to assess both Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) and DSM-5 mental disorders. Two follow-up waves are planned three and six years after baseline. RESULTS: In the first wave, performed from November 2019 to March 2022, 6194 individuals were interviewed: 1576 respondents before and 4618 respondents during the COVID-19 pandemic. The average interview duration was 91 min and the response rate was 54.6%. The sample consisted of 50.4% women and had a mean age of 47.9 years. The sample was reasonable nationally representative, although some sociodemographic groups were somewhat underrepresented. CONCLUSIONS: Despite the COVID-19 restrictions, we were able to build a large and comprehensive dataset of good quality, permitting us to investigate the latest trends in mental health status, various new topics related to mental health, and the extent to which the pandemic has had an effect on the population's mental health.