Psychiatric Illness (Mental Disorders)

Key definitions

• Mental disorder - clinically significant behavioural or psychological syndrome associated with psychological distress or functional disability
• Disability - decreased ability to carry out routine self care, care of dependents, occupation or typical social interactions
• Personality - characteristic emotional and behavioural traits in day-to-day living established in early adulthood and remain stable and predictable
• Personality disorder - maladaptive patterns of relating to and perceiving the environment or themselves that are established in early adulthood
• Emotion - a complex feeling state with psychic, somatic and behavioral components e.g. anxious, pounding heart, fidgeting
• Interpreting and managing symptoms of specific mental disorders is always done in the context of the pre-existing personality traits of the patient

Psychopathology

Aetiology / Pathogenesis

• similar approach to organic (physical) illness
• predisposing, perpetuating, precipitating factors (e.g. genetic predisposition, difficult social situation, recreational drug use)
• can be congenital e.g. mental retardation or acquired e.g. dementia
• often multifactorial and not as clearly defined as for physical illnesses
• typically considered under a biopsychosocial model e.g. depression: adrenergic/serotonergic neurotransmitter deficiency, obsessive personality, traumatic life events

Natural history

• whereas personality traits are pervasive, many psychiatric illnesses can wax and wane with return to normal function e.g. Bipolar Affective Disorder
• the natural history of a psychiatric illness can vary from chronic and unremitting, recurrently episodic to brief and self-limiting

Psychiatric symptoms and Signs

highly developed lexicon of psychological symptoms and signs

Encompasses the following:

• Appearance e.g. dress style, grooming, deportment
• Behaviour e.g. mannerisms, gestures
• Conversation (Speech) - e.g. articulation, coherence, volume, rate
• Thought - form e.g. how words and connections are made; & content e.g. concepts, meaning and thoughts being conveyed
• Affect - observed range of emotions in the immediate context
• Mood - pervasive and sustained emotion being experienced
• Perception - how sensory inputs are registered e.g. hallucinations
• Cognition (see Mini-mental exam below)

Mini-mental exam

• Consciousness - sense of awareness and surrounding
• Alertness
• Memory (includes remote, recent, immediate recall)
• Concentration - with mental tasks e.g. arithmetic
• Attention - response to external stimuli
• Abstraction - e.g. interpreting proverbs
• Reading & Writing
• Visual-spatial ability e.g. drawing or copying diagrams

Classification of mental illness

• various systems but DSM-IV is popular
• ICD-10 includes both organic and psychiatric illness
• by nature any one classification system is arbitrary and there may be multiple ways of organising the observations
• isolated symptoms and signs can be seen in normal patients, those with physical illness or across several mental illnesses
• symptoms may be shared by several conditions but does not mean that the conditions are related or that the significance or aetiology are the same.
• intensity, duration and frequency of symptoms needs to be considered.
• diagnosis is established on the unique patterns and clusters of psychological symptoms and signs (in conjunction with the epidemiological patterns, chronology of illness, likely aetiological factors and response to treatment)
• diagnosis much more heavily reliant on the clinical data rather than adjunctive diagnostics such as imaging and pathology tests
  

DSM formulation

Structures biopsychosocial problems according to the following system as an overview of the issues pertaining to the psychological status of the patient

• Axis I - Major psychiatric illness e.g. schizophrenia, bipolar affective disorder
• Axis II - Personality disorders
• Axis III - Physical disorders - especially chronic illness or acute conditions affecting mental state
• Axis IV - Current psychosocial or environmental stressors
• Axis V - Global assessment of function (over a certain period)

The psychiatric history

• not only focuses on the current symptoms and signs but the chronological development
• chronology focuses on considering the natural and treated history of symptoms and precipitating events
• emphasis is placed on the social and developmental history of the patient that predispose to or perpetuate the illness
• developmental issues include perinatal factors, upbringing, family structure, education, relationship and marital history, established personality traits
• other considerations include family history of psychiatric illness and recreational drug history