CHAPTER 4 Organic psychiatry
General medical conditions are associated with psychological disorders in several ways. This chapter is not meant to be comprehensive, but rather aims to bring attention to important links between psychological function and other body functions. The presence of psychological illness does not exclude the presence of general medical illness and vice versa, even if the diagnosis explains all of the symptoms.
The presence of relevant general medical disorders (‘organic disorders’) must be considered with any presentation of psychological illness, particularly when severe or resistant to treatment. The interaction between general medical disorders and psychological disorders is complex and requires careful consideration. This chapter considers a variety of general medical or organic disorders that can cause significant psychological illness. Box 4.1 presents some of the more common associations between psychological symptoms and general medical disorders.
BOX 4.1 Common psychological disorders and potential contributing general medical disorders
Depressive disorders
Psychiatric disorders secondary to medical disorders
Delirium
Delirium is a syndrome characterised by concurrent disturbances of consciousness and attention, perception, thinking, memory, psychomotor behaviour, emotion and the sleep–wake cycle. Typical symptoms are shown in Box 4.2.
BOX 4.2 Typical symptoms of delirium
Management ultimately requires identification and appropriate treatment of the underlying cause. Management of immediate symptoms and reducing distress for the individual encompasses adequate lighting (to minimise misinterpretation of visual information), minimal noise, a calm, positive and reassuring approach, and a secure environment to maintain safety of self and others. Antipsychotic medications (see Box 4.3) can be helpful for the heightened arousal, anxiety and florid psychotic symptoms, but the response to treatment is often disappointing until the basic cause has been relieved.
BOX 4.3 Medications for the management of delirium
Dementia
Dementia is a syndrome secondary to brain disease which is progressive in nature and is accompanied by disorder of multiple higher cortical functions, including memory, thinking, orientation, comprehension, calculation, learning capacity, language and judgment. It is usually accompanied by deterioration in emotional regulation, social behaviour and/or motivation. It may occur at any age, but is most common in later life. Some forms are reversible, but many are not: common reversible and irreversible types of dementia are shown in Box 4.4. For more on dementia, see Chapter 17.
Huntington’s disease
Clinical features
Onset of the clinical syndrome can occur in adolescence, but is most commonly observed in the fifth decade. Cognitive dysfunction occurs early in the progression of the disease and may include impairment of memory (declarative and non-declarative), impairment of executive cognitive functions (e.g. verbal fluency, planning and sequential activities) and visuospatial skills. Abnormal movements are characteristic of the disease and include chorea and choreoathetosis, as well as impaired occulomotor functions, coordination of movement, dysphagia and dysarthria. Rigidity, bradykinesia, myoclonus/epilepsy, bruxism and dystonia may also arise. Apathy, irritability/aggression, dysphoria, generalised anxiety and obsessive-compulsive disorder arise commonly. Major mood disorders (major depressive disorder or bipolar disorder) and schizophreniform psychosis are seen in many patients with Huntington’s disease. The risk of suicide is very high once the diagnosis has been made.
Management
tetrabenazine (25 mg twice daily, increasing to a maximum of 200 mg daily); side effects can include sedation, depression, insomnia, dysphagia and Parkinsonism, or
Psychosis is treated using antipsychotic medications (see Ch 13). Myoclonus and epilepsy can be usefully helped with anticonvulsants, and botulinum toxin has been employed for bruxism and dystonia. Depression and anxiety disorders require antidepressants.
Acquired brain injury
Post-concussional syndrome and mild traumatic brain injury (TBI)
Mild TBI is defined as closed head injury which is associated with brief loss of consciousness (less than 20 minutes) or none, and anterograde amnesia of less than 24 hours. This may be accompanied by a ‘post-concussional syndrome’ (see Box 4.5).
Symptoms of post-concussional syndrome and mild TBI usually resolve within 6 months, but occasionally become more persistent, particularly when litigation is involved. The pathophysiology would appear to be axonal injury to neurons which usually recover over time. More severe rotational injury can lead to profound cognitive and other impairment.
Frontal lobe syndrome and personality disorder
Injury to the frontal lobes carries many effects, but the ‘frontal lobe syndrome’ refers to a cluster of symptoms and signs associated particularly with damage to the supraorbital prefrontal cortex (see Box 4.6).
BOX 4.6 Frontal lobe syndrome
Cognitive impairment
executive function (e.g. impaired judgment, difficulty with multiple cognitive tasking, abstract thinking, changing case, verbal fluency and rapid changes in motor tasks).
Psychological reactions such as grief, loss of confidence, altered sense of identity and anxiety about performance in tasks can occur in the setting of brain injury. Some people become behaviourally disturbed and aggressive after brain injury: management is as outlined in Chapter 15.
Cerebrovascular disease
Cerebrovascular disease in particular brain regions can provoke psychological illness, but in clinical practice the presentations are often less distinct (Table 4.1).
| Psychological disorder | Site of lesion (any pathology) |
|---|---|
| Depressive disorders | Frontal lobe and basal ganglia; particularly after cerebrovascular accidents and particularly left-sided lesions |
| Lesions in the parietal and occipital lobes, particularly left-sided; can also be associated with depression, but less often and less severely | |
| Mania | Right frontal and temporal lobe lesions, particularly orbitofrontal and basal temporal regions |
| Bipolar affective disorder | Basal ganglia and thalamic lesions, particularly right-sided |
| Anxiety disorders | Cortical lesions, particularly left-sided and left dorsolateral frontal lobe |
| Delusions and hallucinations | Temporo-parietal-occipital region, particularly right-sided |
| Apathy | Posterior internal capsule |
Neoplasia
Raised intracranial pressure can present with unusual symptoms, including atypical behaviour and unexplained headache. Sometimes, the tumour itself can produce neuropsychiatric symptoms, akin to those for cerebrovascular lesions (see Table 4.1).
Epilepsy
Seizures may remain focal in form or become generalised. Most seizures which provoke psychological phenomena are focal in form and the seizure includes psychological symptoms and signs. The core clinical feature of epilepsy is the stereotypic and repetitive nature of its symptoms and signs, which cascade along a regular sequence. Distinguishing some forms of epilepsy from psychological disorders can be difficult, particularly when both are present.
Frontal lobe seizures. These can be characterised by apparently bizarre behaviours, which may be mistaken for ‘pseudo-seizures’ (behaviour which resembles a seizure but is a manifestation of emotional distress). Consciousness may be lost or the seizures may include disruption of language, affect, cognitive function or behaviour.
Endocrine and metabolic disorders
Adrenal cortical disease
Cushing’s syndrome is commonly associated with depression but can also be accompanied by anxiety, cognitive impairment and psychosis. Addison’s disease can be associated with cognitive impairment, and rarely with depression, anxiety and psychosis, including delirium.
Exogenous corticosteroids
These may cause or precipitate mania, depression, irritability and psychosis, including delirium.
Vitamin deficiencies
Thiamine deficiency can precipitate Wernicke/Korsakoff’s encephalopathy (Box 4.7). All B group vitamin deficiencies can be associated with depressive symptoms, encephalopathy and dementia, except perhaps for riboflavin.
BOX 4.7 Wernicke/Korsakoff’s encephalopathy
Psychological responses to general medical conditions
Psychological disorders and interaction with general medical conditions
Endocrine/metabolic functions
Anxiety and depression can provoke significant changes in blood sugar levels and regulation of sex hormone production. Melancholic depression is associated with reduced hypothalamic response to circulating levels of cortisol, thyroxine/liothyronine and growth hormone. Anxiety can reduce release of antidiuretic hormone. Many other endocrine functions are also altered by mental state to a lesser extent. Bipolar disorders may be associated with a higher incidence of hypothyroidism, and schizophrenia is associated with a higher incidence of diabetes mellitus and hyperlipidaemia than occurs in the general population.
Respiratory disorders
CASE EXAMPLES: organic psychiatry
A 46-year-old woman presented with significant mood swings which lasted several weeks and were interspersed with periods of apparently normal mood and function lasting a week or more. She and her husband reported periods of elevated mood with increased spending, pressured speech, rapid shifting of thought content over multiple topics and a reduced need for sleep. While she regarded these times as entertaining and her husband enjoyed her increased libido, playfulness and more stimulating conversation, they both found the episodes exhausting and increasingly irritating. The periods of elation were interspersed with periods of depressed mood and tearfulness, accompanied by social and personal withdrawal. These times were unpleasant for everyone and very distressing. She had been diagnosed with multiple sclerosis about 5 years earlier and suffered fluctuating sensory changes over her body, intermittent reduction of power in her limbs which seemed unpredictable, and lapses in memory which were frustrating. Her behaviour seemed a little disinhibited at times, being overfamiliar with strangers and an inclination to giggle at unusual times. A diagnosis of an organic bipolar affective disorder was made. Management has been predominantly supportive psychotherapy with psychoeducation, but quetiapine gave some extra stability in mental state.
A 21-year-old woman presented with auditory hallucinations of several voices discussing her every action, delusions that her thoughts were being controlled by ‘electric waves’ coming from the house next door and the belief that her body was gradually changing in some peculiar fashion which she found frightening. At times, her speech became disordered with tangential thinking and loss of coherence. She was unable to concentrate at work and had to give up her job in a real estate office. Her parents reported that she had changed in personality over the previous 6 months and that she had spoken about ‘bizarre’ thoughts and was not the person she used to be. They said the changes had occurred at a frightening speed and that she ‘just changed without any warning’. A diagnosis of acute schizophrenia with disorganised features was made. After several weeks she suffered a generalised seizure and began to deteriorate in self-care and grooming. Her cognitive functions deteriorated further with severely impaired memory, poor judgment and increasing perplexity. An electroencephalography (EEG) revealed signs of subacute sclerosing pan-encephalitis (a degenerative disorder secondary to measles infection) and a history of severe measles was obtained from her parents. The diagnosis was changed to an organic schizophreniform psychosis. She continued to deteriorate and died 1 month later.
References and further reading
Clarke D., Kissane D., Trauer T., Smith G. Demoralization, anhedonia and grief in patients with severe physical illness. World Psychiatry. 2005;4(2):96-105.
Kandel E., Schwartz J., Jessell T., editors. Principles of neural science. New York: Elsevier, 2006.
Lishman W. Organic psychiatry. Oxford: Blackwell Scientific; 1998.
Yudofsky S., Hales R., editors. American psychiatric publishing textbook of neuropsychiatry and clinical neurosciences. Washington DC: American Psychiatric Association Publishing, 2002.
