Depression 15 Nov, 2021 Read Time: 2 mins

A constellation of symptoms

The symptoms of depression

Depression is a clinically heterogeneous condition, with a widely underestimated variety of symptoms spanning emotional, physical and cognitive domains.1,2 While patients must present with either depressed mood or anhedonia for a diagnosis of depression to be provided, a selection of the symptoms below can also contribute to their depressed state:1

 

Cognitive symptoms in particular are a poorly understood aspect of depression symptomatology in clinical practice.2 In fact, even DSM-5 does not cover the full range of cognitive symptoms which  present in patients with depression.1

Additional cognitive deficits seen in depression include:3-5

  • Difficulty in maintaining attention
  • Poor organisation/planning
  • Decline in mental sharpness
  • Difficulty learning new concepts
  • Reduced thinking speed
  • Poor judgement
  • Difficulty recalling words

Cognition and depression – the facts

Cognitive symptoms are a significant component of depression in many patients, and often persist beyond the cessation of emotional manifestations like sadness, anxiety and anhedonia1:

  • In a meta-analysis of 644 patients experiencing their first episode of major depression, cognitive performance was significantly impaired across domains including psychomotor speed, attention, visual learning and memory and executive function6
  • In a Dutch study of 267 patients with depression, cognitive symptoms were present 94% of the time during major depressive episodes7
  • In the same Dutch study, cognitive symptoms were shown to persist for an average of 44% of the time during periods of ‘remission’7

 

 

 

 

References

  1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Health Disorders. 5th Washington, DC: American Psychiatric Association; 2013.
  2. Jarema M et al. Cognitive dysfunction in depression – underestimated symptom or a new dimension? Psychiatr Pol 2014; 48(6): 1105-1116.
  3. Marazziti D et al. Cognitive impairment in major depression. Eur J Pharmacol 2010; 626(1): 83-86.
  4. Hammar A, Ardal G. Cognitive functioning in major depression – a summary. Front Human Neurosci 2009; 3-26.
  5. Fehnel SE et al. Patient-centered assessment of cognitive symptoms in depression. CNS Spectr 2013; 25:1-10.
  6. Lee RSC et al. A meta-analysis of cognitive deficits in first-episode Major Depressive Disorder. J Affect Disord 2012; 140: 113-124.
  7. Conradi HJ et al. Presence of individual (residual) symptoms during depressive episodes and periods of remission: a 3-year prospective study. Psychol Med 2011; 41(6): 1165-1174.