Week 3: Epidemiology of Mental Disorder

Question 1

The study of how diseases (or, more broadly, health problems) spread and affect a population.

Answer 1

Epidemiology

Question 2

The study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems.

Answer 2

Epidemiology

Question 3

What does Epidemiology involve?1

Answer 3

1) Defining ‘disorders’
2) Counting and mapping ‘disorders in place and time
3) Linking the occurrence of ‘disorder’ to potential causative factors
4) Identifying appropriate (public health) interventions

Question 4

Two strands of Epidemiology

Answer 4

1) Descriptive Epidemiology
2) Analytical Epidemiology

Question 5

This branch of epidemiology focuses on describing the characteristics of a disease or health condition within a population.

It aims to explain:
- prevalence
- incidence
- variations between populations
- comorbidities
- burden of disorder

Answer 5

Descriptive Epidemiology

Question 6

This branch of epidemiology aims to identify the causes and risk factors of a disease or health condition.

It involves studying different groups of people (e.g., those with and without the disorder) to determine the factors associated with its development.

Answer 6

Analytical Epidemiology

Question 7

Considered one of the founders of modern epidemiology.

His investigation of the 1854 cholera outbreak in London is a classic example of how epidemiological principles can be used to identify the cause of a disease and implement effective control measures.

Answer 7

John Snow

Question 8

A specialized field that applies epidemiological principles to the study of mental disorders.

Answer 8

Psychiatric Epidemiology

Question 9

Goals of Psychiatric Epidemiology

Answer 9

1) Understand mental disorders (onset, course, and outcomes)
2) Measure the burden on society
3) Identify risk factors
4) Develop prevention strategies

Question 10

The underlying biological, psychological, and social processes involved in the development of mental disorders.

Answer 10

Causal Mechanisms

Question 11

The prevalence, incidence, and variation of mental disorders within a population.D

Answer 11

Distribution

Question 12

Key Concepts in Psychiatric Epidemiology

Answer 12

1) Caseness
2) Incidence
3) Prevalence

Answer 12

Caseness

Answer 13

Incidence

Question 14

The presence of a mental disorder as determined by specific diagnostic criteria (e.g., those outlined in the DSM-5).

Answer 14

Prevalence

Question 15

The number of new cases of a mental disorder that occur within a specified period of time, typically a year.

Answer 15

Incidence

Question 16

The proportion of individuals in a population owho have a mental disorder (total number of cases) at a specific point in time (point prevalence) or over a defined period (e.g., one-year prevalence, lifetime prevalence).

Answer 16

Prevalence

Question 17

Steps in conducting Descriptive Epidemiology

Answer 17

1) Identify/define the population of interest
2) Select the sample of the population to study
3) Conduct structured interviews to collect data
4) Analyze data
5) Interpret findings
6) Disseminate results

Question 18

What does Analytical Epidemiology involve?

Answer 18

Population-based studies
Structured analysis
Correlation and causation: Ex. Case-control studies
Various methodologies: Ex. Cohort studies, twin studies, family studies

Question 19

Compare individuals with a mental disorder (cases) to individuals without the disorder (controls).

Answer 19

Case-control Studies

Question 20

Goal: Estimate the prevalence of mental disorders in various communities across the United States

Methods: Structured interviews based on DSM-III

Findings: Prevalence and distribution of mental disorders in different populations

Answer 20

Epidemiological Catchment Area (ECA) Studies (1980s)

Question 21

Goal: Examine the prevalence, comorbidity, and correlates of mental disorders in the United States

Methods: Large-scale survey with structured interviews based on DSM-III-R criteria

Findings: High prevalence of mental disorders, particularly comorbid conditions, and their impact on individuals and society

Answer 21

National Comorbidity Study (NCS) (1990s)

Question 22

Goal: Replicate the findings of the NCS and examine changes in the prevalence of mental disorders over time

Methods: Large-scale survey with structured interviews based on DSM-IV criteria

Findings: Confirmed the high prevalence of mental disorders and identified trends in their occurrence over time.

Answer 22

National Comorbidity Study Replication (NCSR) (2000s

Question 23

Is a statistical measure that compares the probability of an event occurring in an exposed group to the probability of it occurring in a non-exposed group.

Example: Doll and Hill’s study on smoking and lung cancer calculated the relative risk of lung cancer for smokers compared to non-smokers.

Answer 23

Relative Risk or Risk Ratio

Question 24

Key Findings from the National Comorbidity Study Replication (NCSR)

Answer 24

1) Mental illnesses are common
2) Early onset (24 y/o)
3) Serious or moderate severity
4) Comorbidity is common
5) Access to treatment is limited, delayed, or subpar

Question 25

Refers to the process of dividing a population into subgroups based on specific characteristics or variables. These subgroups are often called strata.

Example: In Doll and Hill’s study, the researchers stratified the population of smokers by smoking habits (e.g., light smokers, heavy smokers). This allowed them to examine how the risk of lung cancer varied across different levels of smoking exposure.

Answer 25

Stratification

Question 26

Is a statistical measure that compares the odds of an event occurring in one group to the odds of the event occurring in another group.

It is often used in epidemiological studies to assess the association between an exposure (e.g., smoking) and an outcome (e.g., lung cancer).

Answer 26

Odds Ratio

Question 27

Early epidemiological studies primarily focused on these factors such as migration, urban living, psychosocial stressors, and life events as potential risk factors for mental disorders.

Answer 27

Social Factors

Question 28

Examining the role of inflammation in common mental disorders.

Answer 28

Inflammatory Biomarkers

Question 28

This emerging field combines traditional epidemiological methods with biological and genetic approaches to investigate the underlying causes of mental disorders.

Answer 28

New Psychiatric Epidemiology

Question 28

refers to the underlying processes or factors that contribute to the development of a disease or condition.

In the context of mental disorders, it can involve biological, psychological, social, or environmental factors

Answer 28

Causal Mechanisms