depression

9511213674_31a3c06cc7_z

Introduction

Clinical, unipolar depression is more than just feeling low for a day or two.

Depression is characterised as episodes of sadness, loss of interest and pleasure, often including feelings of low self-worth. Depression can also include a range of physiological symptoms, such as fatigue, pain, diminished appetite, lack of interest in sex, disturbed sleep, and poor concentration.

The World Health Organisation estimates that, globally, as many as 350 million people are affected at any given time, with one person in 20 reporting an episode of depression in a 12 month period (in a global sample of 17 countries). They describe depression as the leading cause of disability worldwide.

What we know already

We know that, despite the considerable global burden of depression, not everybody receives treatment, with figures ranging from 50% to 10% in less developed countries.

Evidence suggests that combined psychological and pharmacological treatments seem to work well. Broadly, we know that psychotherapies work in many cases – but not every time. We know that neurochemical factors, such as serotonergic dysfunction, play an important role in depression, which goes a long way in explaining the efficacy of SSRI treatments.

We also know that depression has a nasty habit of recurrence, and some psychological interventions, such as Mindfulness-Based Cognitive Therapy (MBCT) is recommended particularly for people who have experienced multiple episodes of depression, but not are currently severely depressed.

We know that people living with chronic physical illness are more likely to experience depression, and this combination is linked with poorer clinical outcomes.

Importantly though, we know that people with depression can still enjoy themselves, and a common misconception in depression is that people feel totally awful all of the time.

Areas of uncertainty

There is much still to determine. For example, we know that depression is hereditable, however the extent of heredity versus environmental influences are unclear.

We are also unsure as to the precise mechanisms that determine those who respond best to treatments, be they psychopharmacological, or psychological, or both.

What’s in the pipeline?

Despite advances in our understanding of depression, and how it is treated, it remains a highly recurrent difficulty, with many people not achieving complete remission between episodes.

Preventative interventions, either physiological, or psychological, may improve people’s resilience to depression, particularly those identified as being highly prone.

References

Cuijpers, P. (2015). Psychotherapies for adult depression: recent developments. Current Opinion in Psychiatry, 28, 24-29. [Abstract]

Naylor, C., Parsonage, M., McDaid, D., Knapp, M., Fossey, M. and Galea, A. (2012) Long-term conditions and mental health: the cost of co-morbidities. The King’s Fund, London, UK [PDF]

World Health Organisation (2015).Factsheet 369: Depression [Link]

Photo Credits

Sascha Kohlmann CC BY 2.0

Acknowledgement

Written by: Patrick Kennedy-Williams
Reviewed by:
Last updated: Nov 2015
Review due: Sep 2016

Our depression Blogs

Antidepressants: what is the Smallest Worthwhile Difference?

Performance,Rating,Or,Customer,Feedback,,Credit,Score,Or,Satisfaction,Measurement,

Linda Gask summarises findings from a cross-sectional online survey that investigated the Smallest Worthwhile Difference necessary for individuals with depression to consider taking antidepressants.

[read the full story...]

Cannabis use disorder associated with increased risk of both psychotic and nonpsychotic unipolar depression and bipolar disorder

Cannabis plant

Jack Wilson critiques a recent Danish longitudinal study published in JAMA Psychiatry, which suggests that cannabis use disorder is independently associated with bipolar disorder and unipolar depression.

[read the full story...]

Inflammation and depression: new insights into sex differences in adolescents

Illustration set of 9 different faces of all sexes and races . Also available in other sets.

Sophie Fairweather explores a recent paper which suggests that the inflammatory cytokines IL-2 and IL-6 are associated with both the risk of developing depression, and with depression severity, although this relationship is modified by sex.

[read the full story...]

Shorter sleep and depression: what role do our genes play?

sander-sammy-DIBwWsoshGE-unsplash

Nick Donnelly discusses how one’s genetic predisposition to shorter sleep is associated with the onset of depression in older adults.

[read the full story...]

What’s BESST for young people? Efficacy of CBT-informed workshops for stress management in older adolescents

Portrait,Of,Smiling,Male,And,Female,High,School,Students,Wearing

Matthias Schwannauer explores the BESST cluster randomised controlled trial, which is out today in The Lancet Psychiatry. BESST stands for Brief Educational Workshops in Secondary Schools Trial.

[read the full story...]

Are psychological interventions effective in preventing relapse and recurrence in depression?

Depressed,Woman,Having,A,Counseling,Session

Andrea Cipriani is back, this time writing with Rosario Aronica to summarise an individual patient data meta-analysis on the use of psychological interventions for preventing relapse in depression.

[read the full story...]

How do Black and South Asian women experience perinatal mental health services?

Illustration,Of,A,Pregnant,Woman,With,Perinatal,Depression

KCL Masters student Madeline Katta-Worae considers a UK qualitative study of perinatal mental health services, which explores the experiences of ethnically minoritised women.

[read the full story...]

Keep on movin’… Even small doses of physical activity can lower our risk of depression

A senior man preparing a two-handed basketball shoot.  Isolated on white.

Elli Kypraiou considers a systematic review published in JAMA Psychiatry, which suggests that relatively small doses of physical activity were associated with substantially lower risks of depression.

[read the full story...]

(Brain) sex matters

milad-fakurian-58Z17lnVS4U-unsplash

Paris Lalousis reviews a recent study that looks into the differences in brain connectivity between males and females, which suggests a potential sex-based divergence in the neurobiological underpinnings of psychiatric disorders.

[read the full story...]

From mother to child: the role of racism and trauma in the intergenerational transmission of depression

lawrence-crayton-KXOaNSU63NE-unsplash

Lisa Lloyd and Krupa Sheth summarise a study investigating the role of racism and trauma on the intergenerational transmission of depression between Black mothers and their children.

[read the full story...]