Temperament, adversity may offer clues to psychiatric vulnerability: study, PgII

Key Highlights:

• A transdiagnostic study by researchers at NIMHANS, Bengaluru, found that temperamental traits and adverse childhood experiences (ACEs) together indicate vulnerability to major psychiatric disorders.
• The study, published in the Journal of Affective Disorders, examined 1,162 adults, including those with psychiatric disorders, unaffected first-degree relatives, and healthy controls.
• Participants were drawn from 393 multiplex families with diagnoses of schizophrenia, bipolar disorder, obsessive-compulsive disorder (OCD), and alcohol use disorder (AUD).
• The research identified familial sharing across four temperamental domains despite varied psychiatric diagnoses within families.
• Alcohol Use Disorder (AUD) showed the clearest interaction between temperament and childhood adversity.
• The findings were validated using an independent community-based cohort from the Consortium for Vulnerability to Externalizing Disorders and Addiction (c-VEDA).

Detailed Insights:

• The study investigated four dimensions of adult temperament: negative affectivity, extraversion/surgency, effortful control, and orienting sensitivity.
• Data for the study was sourced from the erstwhile Accelerator programme for Discovery in Brain disorders using Stem cells (ADBS) project, funded by the Department of Biotechnology and Pratiksha Trust.
• The ADBS project is now known as the Rohini Nilekani Centre for Brain and Mind at NIMHANS.
• Specific temperamental characteristics were associated with different disorders; for instance, OCD was linked to higher negative affectivity and orienting sensitivity.
• The study highlighted that temperament does not map onto psychiatric disorders in a simple one-to-one manner, suggesting complex interactions.
• While temperament has a heritable component, the study did not directly establish genetic causation for the observed temperamental characteristics.
• The researchers cautioned that the cross-sectional nature of the study means it cannot establish causation between temperament, childhood experiences, and psychiatric disorders.
• External validation using the c-VEDA cohort indicated that the associations found in family-based samples might extend to broader community populations for some disorders like AUD, bipolar disorder, and OCD.
• The study emphasizes the need for prospective studies to observe unaffected family members over time to determine if temperamental characteristics precede illness onset.

Key Concepts Involved:

• Transdiagnostic Study: Research that examines mechanisms or factors common across multiple psychiatric diagnoses, rather than focusing on a single disorder.
• Temperament: Innate, constitutionally based individual differences in emotional, motor, and attentional reactivity and self-regulation.
• Adverse Childhood Experiences (ACEs): Potentially traumatic events that occur in childhood, such as abuse, neglect, or household dysfunction.
• Multiplex Families: Families in which multiple members have been diagnosed with psychiatric disorders, often used in genetic and familial studies.