Comorbidity Flashcards

Study Notes

Comorbidity Overview

Comorbidity is defined as the co-occurrence of two or more disorders within an individual, which can share etiologies or distinct pathophysiological processes.
Comorbidity is more common than not in clinical and epidemiological settings, affecting a majority of individuals diagnosed with mental illnesses.

Prevalence of Comorbidity

Around 50% of individuals diagnosed with mental illnesses report having a lifetime history of three or more disorders (multi-morbidity).
In clinical samples, up to 95% of individuals with a history of Major Depressive Disorder (MDD) or dysthymia also have an anxiety disorder.
Comorbidity rates are significantly higher for certain disorder pairings than would be expected by chance.

Impact of Comorbidity

Individuals with comorbid conditions experience poorer outcomes, including increased suicidal ideation and impaired social functioning.
Comorbidity is prevalent among both youth and adults and is associated with heightened symptom severity and varied treatment responses.
There is insufficient research on the treatment of comorbid disorders, complicating effective intervention strategies.

High Comorbidity Rates Causes

The precision of the DSM in defining disorder boundaries may contribute to artificially distinct diagnoses.
Increased disorder numbers in the DSM may lead to higher comorbidity rates due to the overlapping symptoms among disorders.
Factors such as sampling bias and risk factors prevalent in certain populations (e.g., low socioeconomic status, childhood maltreatment) exacerbate the comorbidity issue.

Models of Comorbidity

Two primary approaches to understanding comorbidity: Bivariate Models (focused on associations between two disorders) and Multivariate Models (addressing multiple disorders simultaneously).
Bivariate Models include Spurious Association Models and the Associated Liabilities Model, among others, to explain the interrelations between different disorders.

Specific Factors in Comorbidity

Dopamine pathways are implicated in various disorders, linking addiction with depression, schizophrenia, and anxiety.
Genetic and phenotypic models provide insights into the underlying liabilities contributing to mental disorders.

Cognitive/Affective and Information Processing Models

Cognitive models focus on negative self-schemas in depression and hyper-arousal in anxiety, indicating a cyclical interplay between these conditions.
Information Processing Models emphasize selective attention to threat in anxiety and mood congruence in memory pertaining to depression.

Testing and Reducing Comorbidity

Various methods for testing models of comorbidity include epidemiological studies, longitudinal studies, family studies, and treatment studies, revealing shared risk factors and the instability of comorbid conditions.
Potential strategies to reduce comorbidity issues include restructuring diagnostic categories based on symptom overlap and operationalizing conditions under empirically driven classification systems.

Comorbidity Between Specific Disorders

MDD and Generalized Anxiety Disorder (GAD) share symptoms, with over 60% of GAD patients also diagnosed with MDD.
Borderline Personality Disorder exhibits a 33% comorbidity rate with PTSD, often linked to traumatic childhood experiences.
Generalized Social Phobia shows a 59% comorbidity with Avoidant Personality Disorder, raising questions about their classification as distinct disorders or severity levels.
Approximately 75-90% of individuals with Dysthymia have experienced MDD, affirming strong associations between these mood disorders.

Distinct Disorders vs. Subtypes

Distinct disorders display different developmental trajectories, etiologies, brain mechanisms, and treatment responses, as seen in conditions like schizophrenia and ADHD.
Subtypes share the same developmental backgrounds and mechanisms but differ in clinical presentation.

Description

Test your knowledge with these flashcards on comorbidity. Explore definitions, prevalence, and understanding of the co-occurrence of disorders. Perfect for students and professionals in psychology and psychiatry.