Diagnosis and Classification of
Depression
POST IT …
Write down 7
characteristics
of depression?
Aim:
• Can I outline the clinical characteristics of
depression?
• Can I discuss issues relating to the reliability and
validity of diagnosis and/or classification of
depression?
 http://www.healthtalkonline.org/mental_heal
th/Depression/Topic/1495/Interview/875/Cli
p/3322/
Outline
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What is depression
Symptoms
Causes
Types
Risk Factors
 Women
 Elderly
 Young Adults
Outline
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Racial/Ethnic Disparities
Psychosocial/Environmental Factors
Burden
Detailing Messages
What Is Depression?
 A very common, highly treatable, medical
illness.
 Affects physical, mental and emotional
well-being.
 Affects basic, everyday activities like eating
and sleeping.
 Affects how people think about things and
feel about themselves.
What is Depression?
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In contrast to the normal emotional
experiences of sadness, loss, or passing mood
states, clinical depression is persistent and
can interfere significantly with an individual's
ability to function.
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People with depressive illness cannot just “pull
themselves together” and “get over it.”
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Depression often takes on a life of its own –
without treatment, symptoms can last months
or even years.
Symptoms of Depression
 Feeling sad, blue, or down in the dumps
 Loss of interest in things you usually enjoy
 Feeling slowed down or restless
 Having trouble sleeping or sleeping too much
Symptoms of Depression
 Loss of energy or feeling tired all the time
 Having an increase or decrease in appetite
or weight
 Having problems concentrating, thinking,
remembering or making decisions
 Feeling worthless or guilty
 Having thoughts of death or suicide
Symptoms of Depression
 People with Major Depression experience at
least five of these symptoms all day, nearly
every day, for at least 2 weeks.
 The symptoms cause clinically significant
distress or impairment in social, occupational,
or other important areas of functioning.
Causes of Depression
Causes not known, but current theories include:
 Genetic
• Runs in families
• However, depression can also occur in
people who have no family history.
 Environmental
• A serious loss, difficult relationship,
financial problem, or any stressful
(unwelcome or even desired) change in life
patterns can trigger a depressive episode.
Causes of Depression
 Personality Characteristics
 low self-esteem, pessimistic world view, low
stress tolerance
 Whether this represents a psychological
predisposition or an early form of the illness
is not clear.
 Biological
 Continues to be studied extensively
 Current thinking explores problems in brain
functioning in the following areas: Limbic
system, neurotransmitters and neurons,
hormones and the endocrine system
Causes of Depression
 Combination
 a combination of genetic, psychological,
environmental, and/ or biological factors
may contribute to the onset of a
depressive disorder.
Forms of Depression
 Major Depression
 At least 5 of the 9 symptoms of
depression present including either loss of
interest/pleasure or depressed mood;
symptoms interfere with daily functioning
 Minor Depression
 Fewer symptoms than major depression
with significant disability; shorter
duration than chronic depression
Forms of Depression
 Bipolar Disorder
 Cycling mood changes with severe highs
(mania) and severe lows (depression)
 Dysthymia
 Low grade chronic symptoms of
depression that last for a minimum of 2
years
Depression and Suicide
 Of those with MDD, close to 50% report
feelings of wanting to die, 33% consider
suicide and 8.8% report a suicide attempt.
 More than 90% of those who commit suicide
have a diagnosable psychiatric illness at the
time of death, usually depression, alcohol
abuse or both
Who is at risk for Depression?
Anyone is potentially at risk for a depressive
illness. Yet, these groups are believed to be at
higher risk:
 Older adults
 Young adults
 Women, pregnant and post partum women
 Note: women report depression about twice
as often as men. This may result from a
greater likelihood to discuss depression or to
seek help.
Depression in Women
 Depression is the second leading cause of
disease-related disability among women
 1 in 4 women will suffer from a Major
Depressive Episode during the course of their
lives as compared to 1 in 10 men.
• Women may be more likely to discuss
depression or to seek help.
 Women of childbearing age are at increased
risk for major depression
• Pregnancy and new motherhood may
increase the risk of depressive episodes
Depression in Older Adults
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Of the nearly 35 million Americans age 65 and older, an
estimated 2 million have a depressive illness (major depressive
disorder, dysthymic disorder, or bipolar disorder).
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Symptoms of clinical depression can be triggered by other
chronic illnesses common in later life, such as Alzheimer’s
disease, Parkinson’s disease, heart disease, cancer and
arthritis.
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Depression is one of the most common conditions associated
with suicide in older adults.
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Individuals age 65 and older have highest rates of suicide
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High suicide rate among older people (85 and older) is largely
accounted for by White men.
Depression in Young Adults
 10% of college students have been
diagnosed with depression, including 13%
of college women.
 Lifetime prevalence for MDE highest among
young adults age 18-25 (10%)
 Suicide is the third leading cause of death
for those aged 15-24
Additional Risk Factors for
Depression
 Family or personal history of depression
 Current substance abuse problem
 A major life stressor or change in life events;
i.e.: loss of a loved one or a job
 Chronic disease
Depression in Racial/Ethnic
Minorities
 Mental health needs of minority racial/
ethnic groups remain largely unmet .
 Certain groups have higher rates of major
depression
 Native Americans
 Women (middle aged, separated or divorced,
low-income)
 Mexican- American and white individuals
 Have significantly earlier onset of major
depressive disorder compared with African
Americans.
Depression in Racial/Ethnic
Minorities
 Latinos with self reported depression are less
likely to:
 receive any treatment for depression
 fill an antidepressant prescription
 receive adequate course of psychotherapy
 African American and Latinos are more likely
than Whites to be under-diagnosed and undertreated
 Minorities are less likely than Whites to receive
treatments that adhere to treatment guidelines
Explanatory Factors
 Lack of insurance coverage
 Poor access to appropriate screening and early
detection
 Tendency to attribute mental health problems
to religious and other cultural belief systems
 Lack of access to receptive and culturally
compatible providers
Psychosocial/Environmental
Factors
 Psychosocial health has been associated
with mental health in general and with
depression in particular
 Neighborhood social disorganization is
associated with depressive symptoms,
 Living in socio-economically deprived areas
is associated with depression. A recent
study found
 29 % - 58% were more likely to report part 6
month depression
 36% - 64 % were more likely to report lifetime
depression
Depression Burden
Untreated depression causes distress, disability,
and, most tragically suicide.
Depressive disorders are associated with
increased prevalence of chronic diseases (e.g.
asthma, diabetes)
Increased use of general medical services as
well as costlier health services, such as
Emergency Room and Inpatient.
Depression Burden
 Patients who are depressed are more likely to engage in
behaviors that contribute to poor health, such as
smoking, limited or no exercise, poor eating habits and
are likely to have greater difficulty managing their comorbid conditions.
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Depressive disorders are projected to become the
leading cause of disability and the second leading
contributor to the global burden of disease by 2020
 US workers with depression cost employers an estimated
$44 billion per year.
Detailing Messages
 Primary care physicians can effectively detect
and manage depression.
 Routinely screen for depression using a simple
2-question tool (PHQ2)
 Depression can be treated! Medication and
psychotherapy, alone or in combination, can
help most patients.
Detailing Messages
 Primary care physicians can effectively detect
and manage depression.
Detection of Depression: Why Screen
and Manage in primary care?
 Primary care is the 1st line of defense = To find
people who may be depressed or at risk for
depression who don’t know it
 Screening for depression in the primary care setting
improves detection rates
• US Preventative Service Task Force (USPSTF)
recommends screening adults for depression
in clinical practices that have systems in place
for accurate diagnosis, effective treatment,
and follow-up.
 Only 50% of those referred to specialty mental
health practitioners complete more than one visit
Detailing Messages
 Routinely screen for depression using a simple
2-question tool (PHQ2)
Depression Screening: PHQ2
 A physician can simply and quickly screen for
depression by asking 2 questions (PHQ2):
During the past 2 weeks, have you been bothered
by:
1. little interest or pleasure in doing things?
2. feeling down, depressed, or hopeless?
 The PHQ-2 is a valid and practical tool for
depression screening in busy medical settings.
Detailing Messages
 Depression can be treated! Medication and
psychotherapy, alone or in combination, can
help most patients.
Detailing Messages
 More than 80% of people with clinical depression can be
successfully treated.
 Antidepressants are the 1st line treatment for moderate to
severe depression
 About half of the moderate to severe episodes of depression
will improve with antidepressant treatment
 A combination of pharmacotherapy and psychotherapy may
improve treatment response , reduce risk of relapse, enhance
quality of life, and increase adherence to pharmacotherapy.
How RELIABLE are current
methods of diagnosing depression?
 Are the measuring instruments used such as
questionnaires or scales CONSISTENT?
 I will know if…
 Two independent assessors give the similar
diagnosis = INTER-RATER RELIABILITY or
 Test used to deliver the diagnosis are the
same over time = TEST – RETEST
Kraemer et al (2012) – much research
RELIABILITY
on evaluation of medical treatments,
but little on quality of diagnosis
How VALID are diagnostic
measures/classification systems?
 Does it measure something that is real and distinct from
other disorders?
 Does it measure what it claims to measure?
 Comorbidity – extent that 2 or more condition co-occur
 Content validity – does it measure what is sets out to
measure?
 Concurrent validity – extent to which it agrees/corresponds
with (concurs) with other existing standards
Why are reliability and validity
important?
• Faulty diagnosis
• Incorrect treatment
How is depression diagnosed and
measured?
 Structured Clinical Interview for the
assessment of major depressive disorder
 Beck Depression Inventory (BDI)
 International Classification of Diseases
(ICD)
 Diagnostic and Statistical Manual of Mental
Disorders (DSM)
 GP diagnosis/primary care diagnosis
DSM
Used in America
Requires that 5 of the clinical characteristics
occur every day for 2 weeks
+depressed mood or disinterest in pleasure
+impair functioning/cause significant distress
+not simply be attributed to bereavement
Endogenous depression = hormones
Reactive depression = triggered by external
events
Evaluation…
Equally valid to ICD
Keller (1995) – ‘fair to good’ inter-rater reliability but
‘fair’ at best test-retest reliability
This is supported by Zanarini (2000)
Keller suggested that this may be because:
sometimes 1 item disagreement makes a crucial difference for
diagnosis on the threshold (5/9 must be present)
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Zimmerman (2010) deems the DSM-IV too lengthy
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Krupski and Tiller (2001) found only 1/4 Aus and NZ doctors could list
5 symptoms which could lead to unreliable diagnosis
 Zimmerman created a brief version based on DSM based only on the
mood and cognitive symptoms and found 95% agreement with full DSM
IV
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ICD-10
 Used in the UK and Europe
 Very similar to DSM but requires that TWO
of three key symptoms must be present:
 (sad, depressed mood; loss of interest
and/or lack of energy)
 Andrews (1999) found this difference not to
produce a significant number of discrepant
responses = equal validity
Beck Depression Inventory (BDI)
21-item self-report questionnaire
designed to measure severity thus
helping to distinguish between
e.g. major depression and
Lobbesteal et al (2011) = inter-reliability
dysthemia
Research into reliability
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tested the Structured Clinical Interview
mixed sample of patients and non-patient
controls found moderate agreement (coefficient of .66)
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Beck et al (1996) = test-retest reliability
tested responses of 26 outpatients at 2 therapy
sessions one week apart using the BDI
found significant reliability (coefficient.93)
The BDI is also high
in content validity ( as the
criteria based on consensus
among clinicians and based
on psychiatric patients) AND
concurrent validity ( as it
concurs with other measures
such as the Hamilton Depressio
Scale)
Research into validity
 McCullough (2003) found few differences on a range of clinical,
psychosocial and treatment response variables when comparing
outpatients with different types of depression = invalid distinctions
between
different sub-types of depression
• Weel-Baumgarten (2006) suggests that GP
diagnoses may be biased based on previous patient knowledge = invalid
* Comorbidity – often two or more condition co-occur. Specifically, anxiety
disorders and major depression. Goodwin (2001) found suicidal thoughts
with just depression vs no psychiatric disorder to be 5x more likely and tripple
that if depression was combined with an panic disorder.
Cultural Differences
 Karanz (2005) – NY (36 South Asian and
37 European American)
 Tested cultural differences and found that
 Ethnic minorities = identified the ‘problem’
in terms of social and moral terms with suggested
treatments self-management and referral to nonprofessional help.
European Americans = emphasised biological
explanations for the symptoms, including hormonal
imbalance’ and ‘neurological problems’.