History taking

Introduction

Taking a patient’s history (Fig. 1) is the most important part of the clinical assessment. The history is used to find out the nature of the neurological problem, and how it is affecting the patient. It also puts this in the context of previous medical problems, medical problems in the family, occupation and social circumstances, and other aspects of the patient’s life. The elements of a neurological history are the same as for any other subject, but because many neurological diagnoses are based solely on the history it carries greater emphasis (Box 1).

Fig. 1 How to take a neurological history.

The history is usually presented in a conventional way (Box 2) so that doctors being told, or reading, the history know what they are going to be told about next. Doctors often adapt their method depending on the clinical problem with which they are faced. This section is organized in the usual way in which a history is presented, recognizing that sometimes the history can be obtained in a different order.

Basic background information

It is worthwhile establishing initially some basic background information: the age, sex, handedness and occupation, or previous occupation, of the patient. These factors change the patient’s risk of different diseases.

Handedness is important. The left hemisphere controls language in almost all right-handed individuals, and in 70% of patients who are left-handed or ambidextrous.

Presenting complaint

Give the patient the opportunity to describe the problem in his or her own words. This is best done with an open question such as ‘tell me all about it …’ and then avoiding interrupting. Most patients will describe their problems in less than a minute. It is remarkable how often patients will use the same form of words to describe particular problems. For ‘It was like being hit on the head with a bat’, read subarachnoid haemorrhage until proved otherwise. ‘My hands go dead at night. When I wake it helps if I shake them’ suggests carpal tunnel syndrome. ‘The pain in my cheek is sudden, like a red hot needle’ suggests trigeminal neuralgia.

Frequently patients have trouble describing the feelings or sensations that they have experienced. This will require you to help interpret what they tell you – from everyday language into medical English. Patients find some sensations particularly difficult: for example, dizziness can mean light-headedness, a sensation of rotational vertigo or a feeling of being distant, among others (p. 46); the term numbness can be used by patients to mean weakness, loss of sensation or stiffness. Your knowledge of the range of symptoms that people feel will help to sort out what the patient means.

After clarifying the nature of the symptoms you need to determine the time course. Establish the onset of the symptoms (sudden or gradual), their progression (progressive, stepwise or intermittent) and their duration. If possible, some sort of measure should be used: how far the patient could walk at various times, when the patient started to use a walking stick, and so on. The time course is critical to interpretation of the history. For example, a 50-year-old woman has had an episode of unilateral visual loss:

If it was of sudden onset (‘like a shutter coming down’) and resolved over 5 min, she has had amaurosis fugax (a retinal transient ischaemic attack).

If it developed progressively from the centre of the vision over 15 min with bright lights at the edges, resolving after 15 min followed by a headache, it was a migraine aura.

If there was a gradual loss of vision over 24 h with pain on eye movement and gradual recovery over 6 weeks, it was optic neuritis.

A 60-year-old man has developed a right-sided weakness affecting his face, arm and leg:

If of sudden onset, he has had a stroke.

If it developed over 10 days, beginning 10 days after a moderate head injury, it is probably a subdural haematoma.

If it developed over 4 months, it is probably a tumour.

Hypothesis testing

The next stage is to develop hypotheses on the basis of the initial description as to the possible site of the abnormality or type of syndrome. These hypotheses can be tested by:

Asking about other symptoms that might further help to localize the cause of the symptoms. For example, a 45-year-old man has a slowly progressive weakness and stiffness in both legs and tends to trip on small steps. His symptoms suggest a bilateral upper motor neurone lesion so you should ask about (i) other symptoms of spinal cord lesions – sensory symptoms in the legs and bladder and bowel function; (ii) the upper level of the symptoms – if the arms are affected this suggests cervical cord disease, if there are brain stem symptoms then the lesion must be higher, or there is more than one lesion; (iii) other clues that might suggest the level such as back or neck pain.

Asking about other recognized symptoms of a particular clinical syndrome. For example, in a patient with suspected Parkinson’s disease, asking whether there has been any change in the writing; in suspected multiple sclerosis, asking if symptoms are worse after a bath or in hot weather.

Asking about risk factors for the condition and associated diseases. For example, in a patient in whom you suspect a stroke, asking about vascular risk factors (hypertension, smoking, diabetes) and associated vascular disease (ischaemic heart disease, peripheral vascular disease).

This process may involve testing more than one hypothesis.

Common difficulties in taking a history

Too much incidental detail: ‘Do you know Gloucester at all? Well, just behind the bus station there’s a chemist …’ Gently redirect the patient to give more relevant history.

Lists of medical contacts: ‘So I went to see my doctor, and he said … And then the specialist in Oxford thought …’ If you need to know what another doctor did or thought, contact them directly.

Forgetting everyday events: most young women taking the oral contraceptive pill do not consider this to be tablets or medicines so you have to ask directly about them.

History needed from someone else: ‘The first I knew about it was when I came to in the hospital’. In patients with blackouts or altered consciousness and impairment of higher function it is important to get a witnessed account of events from whoever is available – relative, friend or passer-by.

History just doesn’t seem to make sense: this tends to happen in patients with speech problems, memory or concentration difficulties and in patients with non-organic disease. Think of aphasia, depression, dementia and hysteria.

Neurological screening questions

After the investigative phase of history taking, usually one asks further standard screening questions for other aspects of neurological disease (Box 3). If the hypothesis is correct this usually does not throw up any surprises.

Box 3 Neurological screening questions

Do you have, or have you had?

headaches

memory disturbance

dizziness or giddiness

blackouts

change in taste or smell

visual problems

double vision

difficulty with speech

difficulty with swallowing

weakness in your arms or legs

numbness or tingling

Past medical history

This needs to be documented. It is always useful to consider the basis for any diagnosis given by the patient. For example, a patient whose past medical history starts with ‘known epilepsy’ may not have epilepsy, but once accepted it rarely gets questioned and patients may be inappropriately treated.

Drug history

Current therapy is important. In some conditions, prior exposure to particular drugs can be important: for example, movement disorders can occur following phenothiazine exposure, whether taken for psychiatric indications, sickness or as a vestibular sedative. Young women often forget to mention that they take oral contraceptives.

Family history

Many of the degenerative diseases of the nervous system are familial. It is important to take a detailed family history when those conditions are being considered. In some circumstances patients can be reluctant to tell you about certain inherited problems, for example Huntington’s disease. On other occasions other family members can be very mildly affected: for example, in the Charcot Marie Tooth disease, some family members will simply be aware that they have high arched feet. This can also be sought in the history.

Drawing a family tree is often helpful: a ‘negative’ family history is more informative in a large family than in an only child.

Social history

The impact of a neurological problem will vary according to the social circumstances of an individual and this will be important in the further management of a patient. For example, a heavy-goods vehicle driver diagnosed with epilepsy will lose his job but epilepsy may have much less effect on someone who can take public transport to work.

The home circumstances, housing, family support and finances of a patient with a neurological disability are very important in the management.

The detail required depends on the clinical problem. In a patient with difficulty walking, the home circumstances need to be clearly defined. (Are there stairs? Is there a toilet downstairs? Are there steps between rooms or into the home?) The level of social support available may significantly affect management: a patient with an able-bodied spouse may be able to manage at home with a greater disability than someone living alone. Such details are redundant in a patient who only complains of a headache.

It is important to try to consider the whole patient and how the neurological problem may affect the patient’s life.

History taking

The history is the most important part of the clinical assessment.

The time course of the symptoms gives an insight into the pathological process.

The history should be used to construct and test hypotheses about the diagnosis.

The history is used to put the current problems into the context of the patient’s previous medical problems, their family history and their social and financial situation.