Cohort Profile Update: Mental Health Online Survey in the Estonian Biobank (EstBB MHoS)

Mental health problems, such as depression, anxiety, substance abuse and stress-related problems, are common in populations worldwide. It has been estimated that 30% of people are affected by a mental disorder during their lifetime. 2These disorders are associated with a notable societal burden, including reduced quality of life, increased healthcare costs and loss of productivity. 3However, psychiatric disorders are characterized by significant clinical heterogeneity and frequently exhibit a considerable overlap of symptoms and comorbidities across disorders that complicates clinical decision-making, thus affecting patient outcomes. In addition, the genetic investigations of psychiatric disorders are also affected by this heterogeneity. Non-specific phenotypes may lead to non-specific associations in genome-wide studies, Key Features• The Estonian Biobank (EstBB) is a population-based biobank cohort that currently comprises >212 000 individuals, representing 20%of the adult population in Estonia. EstBB is linked to and regularly updated with the national electronic health records (EHRs). • The Mental Health Online Survey (EstBB MHoS) was conducted in 2021 to significantly expand phenotyping on a broad range of mental health symptoms and related phenotypes not available in EHRs to facilitate research in psychiatric genomics. • A total of 86 244 individuals participated in the EstBB MHoS (age range 18-100 years), corresponding to a participation rate of 46. 7%. • The EstBB MHoS collected information on increased risk for various mental conditions, including current and lifetime depression, anxiety, mania, post-traumatic stress, disordered eating, alcohol and substance abuse, attention-deficit/hyperactivity disorder, adverse childhood and adulthood experiences, as well as psychiatric medication usage and treatment outcomes.