Depression Flashcards
Depression
treated as a mood disorder alongside bipolar disorders
opposite is mania
DSM Criteria
persistent depressed mood and/or marked loss of interest
at least 5 of the following symptoms (change in weight/appetite, altered sleep, psychomotor agitation/retardation, fatigue/loss of energy, worthlessness/guilt, impaired concentration/indecision, thoughts of death)
lasts at least 2 weeks
clinically significant impairment
symptoms not better accounted for by other conditions or due to effects of substance use
Issue in diagnosis
5 symptoms needed but some people may only experience 3 yet feel equal or greater distress and impairment in functioning
Epidemiology
Waraich et al., 2004 - lifetime risk is 4-10% for major depression
average age for first onset = 20 years
2x more common in women than men
rare in children (Nolen-Hoeksema, 2002)
episodic, average episode lasts 6-months
Simon et al., 2002 - 50% still have diagnosis after 1 year
Relapse and recurrence
for many it is recurrent
Belsher and Costello, 1988 - 50% relapse after 1 year
Kupfer, 1991 - 90% of those who have had three episode will have another episode whereas 50% of those who have one episode will have further episodes
Impact of depression
Thomas and Morris, 2003 - at least £8 billion lost productivity in UK annually
at least £370 million spent on treatment in UK annually - 84% of this is on antidepressant medication
stigmatisation - if this becomes normalised through treatment as biological illness then run risk of medicalisation of normal everyday experience of negative emotions
Approaches to depression
Biological: neural processes, genetics
Psychological theories: psychodynamics, behavioural model (reward and reinforcement), cognitive model (learned helplessness)
Social theory: life events
Aetiology:
Biological approach
Neurochemical processes
serotonin and norepinephrine found to be important in depression (low levels)
many of these theories are inconsistent and difficult to understand
quite simplistic
Aetiology:
Biological approach
Genetic influence
depression shares some extent of heritability - but not greatly
Sullivan 2000 - meta-analysis of family/twin studies - found although depression is heritable, environmental influences are substantial
Plomin, 1990 - twins interviewed regarding negative life events - estimate heritability of controllable and uncontrollable life events - genes found to influence likelihood that certain types of negative events will occur
Aetiology:
Psychodynamic approach
depression is response to loss
first stage response = introjection (fallback to oral stage) - begin to experience self-hatred
not everyone has experienced loss so introduced symbolic loss (loss of significance to individual)
some empirical evidence but evidence also supports other psychological theories
Aetiology:
Behavioural approach
Reward and reinforcement
Fester, 1973; Lewinsohn, 1974
symptoms are consequence of low rates of positive reinforcement
non-rewarded behaviours no longer performed - extinction - leads to inertia/inactivity and behavioural vacuum
depressed mood changes behaviour and social skills impaired
Support for behavioural approach
Lewinsohn and Graf, 1973 - 90 participants interviewed about daily activities - depressed group had lower positive activities than control groups - no. of positive activities correlated significantly with mood
Jacobson et al., 2004 - those with depression report fewer rewards in their life than those without depression- introduction of rewards elevates mood
Aetiology:
Cognitive approach
Learned helplessness
Seligman, 1975 - negative life events may lead to a cognitive set that teaches individuals to become helpless, lethargic and depressed
perceived uncontrollability of these life events results in thinking that these negative life events will happen whatever they do
support: Seligman, 1975
- dogs subject to inescapable shock, found escape responses were later impaired, learned helplessness proposed to have parallels with depression
Abramson, 1989 - adds in hopelessness - belief that negative events will recur
Aetiology:
Cognitive approach
Negative cognition
Beck, 1967
depression caused by biases in thinking and processing information
formation of negative schema - negative triad (negative views of self, world and future)
so when critical incidents occur these schemas are activated and lead to automatically negative thoughts and depressive symptoms
Support for negative cognition approach
Gotlib and Cane, 1987 - depressed individuals were slower at naming colour of negative words (emotional stroop test) than positive words - suggests attention drawn to meaning of negative words
Miranda and Persons, 1988 - 30 women with depression, 13 without - dysfunctional attitude scale assess cognition proposed by Beck - depression vulnerable individuals showed increases in depressogenic cognition with increasing negative mood
Aetiology:
Social factors
Life events
Finlay-Jones and Brown, 1991 - 151 women - life events assesed 12-m prior to interview or disorder onset - depression primarily associated with loss events, anxiety with danger events
Aetiology:
Social factors
Vulnerability model
Brown and Harris, 1978 - sample of women - higher rates of life events and depression in working class vs middle class women - social difficulties/vulnerability factors alone are not triggers of depression but do increase proneness
Limitations of social theory (4)
issues in assessing life events
descriptive not explanatory
not all depressive episodes preceded by negative life event
limited implications for treatment
Treating depression:
NICE, 2004
should be tailored to severity of symptoms - stepped-care model
- GPs advised to ensure proper assessment not just medication
- medication should be only for moderate to severe depression
- mild depression to be treated with brief behavioural and cognitive interventions first
Treating depression:
Biological therapy
Drug therapy
try to address imbalance of serotonin and norepinephrine
3 main types: tricyclic drugs, monoamine oxidase inhibitors and selective serotonin reuptake inhibitors
most common are SSRIs
Support for drug therapy
Fournier, 2010 - effectiveness of drugs increases with severity of symptoms
Gitlin, 2002 - approx. 60-65% those on tricyclic drugs show improvement
Thase et al., 1995 - 50% of those on MAOIs show improvement
Limitations of drug therapy
no evidence for long term benefits once stopped - relapse common
it is more effective to combine it with psychological therapies
Hollon et al., 2005 - overall results of effectiveness of drug therapy are disappointing
Treating depression:
Biological therapy
ECT
first discovered in 1938
originally used for schizophrenia, now used for severe depression
pass current through head for approx. 30 secs
only short-term relief
many side effects - i.e. memory loss
Treating depression:
Psychological therapy
Behavioural activation therapy
negative life event may represent loss of important sources of reward and reinforcement
aims to increase access to pleasant events and rewards
setting patterns of activities and getting routine
Dimidjian et al., 2006 - treats avoidance behaviours and targets maladaptive behaviours
Support for behavioural activation therapy
Gortner et al., 1998 - as effective as CBT in preventing relapse after 12 months
Treating depression:
Psychological therapy
Cognitive therapy
one of most successful and most widely adopted therapies
developed by Beck
structured treatment
teaches client to recognise negative thinking patterns, re-evaluate these using cognitive and behavioural strategies, challenge these negative thoughts and then replace them
Support for cognitive therapy
Rush et al., 1977 - as effective as drug therapy in treating symptoms
Blackburn and Moorhead, 2000 - superior to drug therapy at 1 year follow up
Challenge to cognitive therapy
still some debate over how it achieves its effects
Treating depression:
Psychological therapy
Mindfulness-based cognitive therapy
attempt to combat linkage between periods of dysphoria and onset of negative thinking - prevent relapse
learn to recognise automatic modes and respond by taking decentred perspective, accepting difficulties and following action plan for dealing with early indicators of relapse
Support for MBCT
Piet and Hougaard, 2011 - 593 pps in meta-analysis - MBCT reduced risk of relapse by 34% compared to usual treatment or placebo
Ma and Teasdale, 2004 - MBCT reduced relapse from 78% to 36% - significant therapeutic gains
