History
A 71-year-old ex-cleaner is brought to the follow-up neurology clinic by her daughter and a carer from the residential home where she resides. She has been diagnosed with Parkinson’s disease for 7 years and has managed reasonably well with a combination of caribidopa 25 mg and levodopa 100 mg two tablets three times daily. Her cognition has been worsening gradually from a Mini Mental State Examination score of 24/30 two years ago to 20/30 on her current visit. She reports no change in herself but her daughter says that over the past 6 months her mother has been exhibiting periods of ‘weird behaviour’ – screaming and shouting for hours followed by periods of tearfulness and uncontrollable sobbing. When agitated, she has been disinhibited, taking her clothes off and swearing in a manner very uncharacteristic of her. She sings loudly and cheerfully making everyone laugh with ‘lewd jokes’. When tearful, she has appeared profoundly slowed down and has spoken of wanting to stay in bed, not being able to face the day ahead. Her sleep has been disturbed and so too her appetite. At times, she has refused to go down to the dining room. Her mobility has worsened. Her shuffling gait and tremors have worsened and so too her bradykinesia. According to her carer, her personality has changed a lot over the past year or so. She has become more reserved and does not enjoy bingo or shopping trips. She does look forward to her daughter’s visit, but of late has not been as enthusiastic as she used to be. Her daughter visits her three times a week and is very close to her. Her husband died 10 years ago. She has settled well at the residential home and is quite popular with staff and other residents. She has no history of any other physical or psychiatric illness.
Mental state examination
She appears well-dressed though there is some evidence of self-neglect. Her hair looks messy and her nails are dirty. She walks in with a stooped posture and takes slow shuffling steps. She has a prominent resting tremor when she sits down. Her head nods and her hands rhythmically move. She is cooperative, pleasant and establishes a good rapport. She reports her mood to be normal but on direct questioning she becomes tearful, saying she can’t help crying. Her affect is blunted. Her speech is soft and slow. There is no formal thought disorder. Cognitive examination reveals impairments in attention span, registration, recall, writing, construction and 3-stage command. She has some insight into her condition, acknowledging her mobility problems and the need for treatment. However, she denies being disinhibited saying ‘she was just being happy’.
ANSWER 70
This woman has a diagnosis of Parkinson’s disease (PD), which is being treated with levodopa. She is now presenting with lability of mood associated with further deterioration of her cognitive abilities and her movement disorder. Differential diagnoses that need to be considered include the following:
• Dementia – risk of dementia may be increased up to three-fold in patients with PD.
The majority of PD patients may have mild dementia characterized by memory problems and slow thinking, as may be likely in this case and up to 20% may progress to severe dementia. The presence of cognitive changes must lead to referral to a psychiatrist or a neurologist to consider the possible diagnosis of dementia and its possible aetiology, including vascular dementia, Huntington’s disease,
Hallervorden–Spatz disease, progressive supranuclear palsy and other rare conditions which may present with cognitive deterioration and movement disorder.
• Depression – is seen more commonly in PD (nearly 50%) than in other similar
disabling conditions and is unrelated to duration of illness or to level of disability. PD may often present with symptoms of depression or anxiety. Females are more likely to be affected. Emotional insecurity, pessimism, lack of confidence in socializing or going out, poor motivation and increased concern about health are more common presenting symptoms.
• Mania – manic or other psychotic episodes are extremely rare in PD though
psychotic depression may be seen in a small proportion of cases.
• Iatrogenic – psychosis, affective disorders, delirium and impulsive behaviours can
occur as iatrogenic conditions secondary to overmedication with levodopa or anticholinergic medications. Impulsive behaviours can include hypersexuality, dopamine dysregulation syndrome with addiction to dopaminergic medications, as well as compulsive, addictive, repetitive or reward seeking behaviours. Fourteen per cent of patients on dopamine agonists engage in pathological or harmful gambling. Up to 3% of PD patients seen in specialist clinics exhibit hypersexuality or dopamine dysregulation. Psychiatric side effects are seen in 10% of cases increasing up to 60% in those on treatment over 6 years. Psychotic episodes, with delusions and
hallucinations, may be precipitated in those with past history of psychosis or may occur as a new episode later in treatment. Visual hallucinations are more common (unlike schizophrenia where auditory hallucinations predominate) and insight is often preserved. They usually respond to reduction of antiparkinsonian treatment. Where this is not possible, treatment with atypical antipsychotics is appropriate, but with careful vigilance for worsening of motor symptoms. Mood disorders including mania, severe depression and anxiety can occur as treatment complications. Acute
confusional states with disorientation and hallucinations may also be seen.
In this case, there are periods of low mood and tearfulness alternating with periods of hyperactivity, agitation and elated mood. This is most likely associated with on–off periods related to medication.
• Psychiatric complications such as depression, mania, psychosis and cognitive disorders such as dementia or delirium are often associated with PD and/or secondary to medications used to treat PD.
• These complications increase with chronicity of illness and treatment and a high index of suspicion is needed to identify and effectively treat them.
KEY POINTS
History
A surgical colleague rings you up. He has a 75-year-old woman who needs an operation to remove a breast lump. The lump is malignant but is isolated and there is no evidence of any local or distant spread. Your colleague explains he has told the woman that the operation is fairly straightforward and that after the operation she would be treated with radiotherapy. He states that she is saying she has no wish to have the operation. He is struggling to understand her decision because not having the operation reduces her chances of survival. He wants you to come and assess her because he feels she must have a mental illness which is rendering her incapable of making the right decision.
Questions
• Who should assess capacity?
• What conditions must be fulfilled for a person to have capacity to make a particular decision?
• What should happen here?