Doctor and patient: General principles of history taking

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1 Doctor and patient

General principles of history taking

Michael Glynn

Introduction

If asked why they entered medicine, most doctors would say that they wish to relieve human suffering and disease. In order to achieve this aim for every patient, it is essential to understand what has gone wrong with normal human physiology in that individual, and how the patient’s personality, beliefs and environment are interacting with the disease process. History taking and clinical examination are crucial initial steps to achieving this understanding, even in an era in which the availability of sophisticated investigations might suggest to a lay person that a blood test or scan will give all the answers. In addition, the distinction between cure of disease and relief of symptoms remains as valid today as in the past. No patient should leave a medical consultation feeling that nothing can be done to help them, even when the disease is incurable.

Clinical methods – the skills doctors use to diagnose and treat disease – are acquired during a lifetime of medical work. Indeed, they evolve and change as new techniques and new concepts arise, and as the experience and maturity of the doctor develop. Clinical methods are acquired by a combination of study and experience, and there is always something new to learn.

The aims of any first consultation are to understand patients’ own perceptions of their problems and to start or complete the process of diagnosis. This double aim requires a knowledge of disease and its patterns of presentation, together with an ability to interpret a patient’s symptoms (what the patient reports/complains of, e.g. cough or headache) and the findings on observation or physical examination (called physical signs or, often, simply ‘signs’). Appropriate skills are needed to elicit the symptoms from the patient’s description and conversation, and the signs by observation and by physical examination. This requires not only experience and considerable knowledge of people in general, but also the skill to strike up a relationship, in a short space of time, with a range of very different individuals.

There are two main steps to making a diagnosis:

1 To establish the clinical features by history and examination – this represents the clinical database.

2 To interpret the clinical database in terms of disordered function and potential causative pathologies, whether physical, mental, social or a combination of these.

This book is about this process. This chapter introduces the basic principles of history and examination, while more detail about the history and examination of each system (cardiovascular, respiratory, etc.) is set out in individual succeeding chapters. Throughout the book, the patient is referred to as ‘he’, the editors preferring this to ‘he/she’ or ‘they’ (except in specific scenarios involving female patients).

Setting the scene

Most medical encounters or consultations do not occur in hospital wards but in a primary care or outpatient setting. Whatever the setting, a certain stability to the context of the consultation, including the consulting room itself, the waiting area and all the associated staff, makes the process of clinical diagnosis easier. Patients are less often assessed in their own home than previously, and many doctors now find this a strange concept.

Meeting the patient in the waiting room allows the doctor to make an early assessment of his demeanour, hearing, walking and any accompanying persons. It is good to offer a greeting and careful introduction and to observe the response unobtrusively, but with care. Patients are easily confused by medical titles and hierarchies. All of the following questions should be quickly assessed:

Does the patient smile, or appear furtive or anxious?

Does the patient make good eye contact?

Is he frightened or depressed?

Are posture and stance normal?

Is he short of breath, or wheezing?

In some conditions (e.g. congestive heart failure, Parkinson’s disease, stroke, severe anaemia, jaundice), the nature of the problem is immediately obvious. It is very important to identify the patient correctly, particularly if he has a name that is very common in the local community. Carefully check the full name, date of birth and address.

Pleasant surroundings are very important. It is essential that both patient and doctor feel at ease, and especially that neither feels threatened by the encounter. Avoid having patients full-face across a desk. Note taking is important during consultations while being able to see the patient and establish eye contact, and to show sympathy and awareness of his needs during the discussion of symptoms, much of which may be distressing or even embarrassing. If the doctor is right-handed and the patient sits on their left, at an angle to the desk, the situation is less formal, and clues such as agitated foot and hand movements are more evident. If other people are present, arrange the seating to make it clear that it is the patient who is the centre of attention, rather than any others present.

History taking

Having overcome the strangeness of meeting and talking to a wide variety of people that they might not ordinarily meet, the new medical student usually feels that history taking ought to be fairly simple but that physical examination is full of pitfalls such as unrecognized heart murmurs and confusing parts of the neurological examination. However, the experienced doctor comes to realize that history taking is immensely skilled, and that the extent to which skill increases with experience is probably greater than for clinical examination.

Beginning the history

The process of gathering information about a patient often begins by reading any referral documentation and with the immediate introduction of doctor and patient. However, once the social introductions are achieved, the doctor will usually begin with a single opening question. Broadly, there are two ways to do this.

A single open-ended question along the lines of ‘Tell me about what has led up to you coming here today’ gives the opportunity for the patient to begin with what he feels to be most important to him and avoids any prejudgement of issues or exclusion of what at first hearing may seem less important. However, at this stage the patient may be very anxious and nervous and still making his own assessment of how he will react to the doctor as a person. A beginning which focuses on issues which may be more factual and less emotive can be more rewarding and lead to a more satisfactory consultation. Box 1.1 lists some of the areas of questioning that can be usefully included at the beginning of the history. It is important to inform the patient that this is going to be the order of things, so that he does not feel that his pressing problems are being ignored. A statement along the lines of ‘Before we discuss why you have come today, I want to ask you some background questions’ should inform the patient satisfactorily.

Box 1.1 Areas of questioning that can be covered at the beginning of history taking

Confirm date of birth and age

Occupation and occupational history

Past medical history

Smoking

Alcohol consumption

Drug and treatment history

Family history

There is a particular logic in taking the past medical history at this stage. For many conditions, the distinction as to what is a current problem and what is past history is unclear and arbitrary in the patient’s mind. A patient presenting with an acute exacerbation of chronic obstructive pulmonary disease may have a history of respiratory problems going back many years. Therefore, taking the history along a ‘timeline’ will often build up a much better picture of all of the patient’s problems, how they have developed and how they now interact with life and work.

Once these preliminaries have been completed, the doctor should use a simple and open-ended question to encourage the patient to give a full and free account of the current issues. Say something along the lines of ‘Tell me about what has led up to you coming here today’. This wording leaves as open as possible any question about the cause of the patient’s problems and why he is seeing a doctor, and could give rise to an initial answer beginning with such varied phrases as ‘I have this pain …’, ‘I feel depressed …’, ‘I am extremely worried about …’, ‘I don’t know but my family doctor thought …’, ‘My wife insisted …’ or even ‘I thought you would already know from the letter my family doctor wrote to you’. All these answers are perfectly valid but each gives a different clue as to what are the real issues for the patient, and how to develop the history-taking process further for that individual.

This part of history taking is probably the most important and the most dependent on the skill of the doctor. It is always tempting to interrupt too early and, once interrupted, the patient rarely completes what he was intending to say. Even when he appears to have finished giving his reasons for the consultation, always ask if there are any more broad areas that will need discussion before beginning to discuss each in more detail.

Developing themes

This stage of the history is likely to see the patient talking much more than the doctor, but it remains vital for the doctor to steer and mould the process so that the information gathered is complete, coherent and, if possible, logical. Some patients will present a clear, concise and chronologically perfect history with little prompting, although they are in the minority. For most patients, the doctor will need to do a substantial amount of clarifying and summarizing with statements such as ‘You mean that …’, ‘Can I go back to when …’, Can I check I have understood …’, So up to that point you …’, ‘I am afraid I am not at all clear about …’ and ‘I really do not understand, can we go over that again?’ If a patient clearly indicates that he does not wish to discuss particular aspects of the history, then this wish must be respected and the diagnosis based on what information is available, although it is also important to explain to the patient the limitations that may be imposed by this lack of information.

Non-verbal communication

Within any consultation, the non-verbal communication is as important as what the patient says. There may be contradictions such as a patient who does not admit to any worries or anxieties but who clearly looks as if he has many. Particular gestures during the description of pain symptoms can give vital clinical clues (Box 1.2). While concentrating on the conversation with the patient, the doctor should keep a wide awareness of all other clues that can be gleaned from the consultation. These include the patient’s demeanour, dress and appearance, any walking aids, the interaction between the patient and any accompanying people and the way that the patient reacts to the developing consultation.

Box 1.2 Particular gestures useful in analysing specific pain symptoms

A squeezing gesture to describe cardiac pain

Hand position to describe renal colic

Rubbing the sternum to describe heartburn

Rubbing the buttock and thigh to describe sciatica

Arms clenched around the abdomen to describe mid-gut colic

It is very important to use vocabulary that the patient will understand and use appropriately. This understanding needs to be on two levels: he must understand the basic words used, and his interpretation of those words must be understood and clarified by the doctor. Box 1.3 lists words and phrases that may be used in the consultation that the doctor needs to be very careful to clarify with the patient. If the patient uses one of the ordinary English words listed, its meaning must be clarified. A patient who says he is dizzy could be describing actual vertigo, but could just mean light-headedness or a feeling that he is going to faint. A patient who says that he has diarrhoea could mean liquid stools passed hourly throughout the day and night, or could mean a couple of urgent soft stools passed first thing in the morning only. Therefore, the doctor needs to use words that are almost certainly going to be clearly understood by the patient, and the doctor must clarify any word or phrase that the patient uses, to avoid any possibility of ambiguity.

Indirect and direct questions

Broadly, questions asked by the doctor can be divided into indirect or open-ended and direct or closed. Indirect or open-ended questions can be regarded as an invitation for the patient to talk about the general area that the doctor indicates is of interest. These questions will often start with phrases like ‘Tell me more about …’, ‘What do you think about …’, ‘How does that make you feel …’, ‘What happened next …’ or ‘Is there anything else you would like to tell me?’ They inform the patient that the agenda is very much with him, that he can talk about whatever is important and that the doctor has not prejudged any issues. If skilfully used, and if the doctor is sensitive to the clues presented in the answers, a series of such questions should allow the doctor to understand the issues that are most important from the patient’s point of view. The patient will also be allowed to describe things in his own words.

Many patients are in awe of doctors and have some conscious or subconscious need to please them and go along with what they say. If the doctor prejudges the patient’s problems and tends to ‘railroad’ the conversation to fit their assumed diagnosis too early in the process, then the patient can easily go along with this and give simple answers that do not fully describe his situation. Box 1.4 illustrates this extremely simple, common and important pitfall of history taking.

Box 1.4 Example of a history that leads to a poor conclusion

A GP is seeing a 58-year-old man who is known to be hypertensive and a smoker. The receptionist has already documented that he is coming in with a problem of chest pain. The GP makes an automatic assumption that the pain is most likely to be angina pectoris, because that is probably the most serious cause and the one that the patient is likely to be most worried about, and therefore starts taking the history with the specific purpose of confirming or refuting that diagnosis.

GP: I gather you’ve had some chest pain?

Patient: Yes, it’s been quite bad.

GP: Is it in the middle of your chest?

Patient: Yes.

GP: And does it travel to your left arm?

Patient: Yes – and to my shoulder.

GP: Does it come on when you walk?

Patient: Yes.

GP: And is it relieved by rest?

Patient: Yes – usually.

GP: I’m afraid I think this is angina and I will need to refer you to a heart specialist.

The GP has only asked very direct and closed questions. Each answer has begun with ‘Yes’. The patient has already been quite firmly tagged with a ‘label’ of angina, and anxiety has been raised by the specialist referral.

Alternatively, the GP keeps an open mind and starts as follows:

GP: Tell me why you have come to see me today.

Patient: Well – I have been having some chest pain.

GP: Tell me more about what it’s like.

Patient: It’s in the centre of my chest and tends to go to my left arm. Sometimes it comes on when I’ve been walking.

GP: Tell me more about that.

Patient: Sometimes it comes when I am walking and sometimes when I’m sitting down at home after a long walk.

GP: If the pain comes on when you are walking, what do you do?

Patient: I usually slow down, but if I’m in a hurry I can walk on with the pain.

GP: I am a little worried that this might be angina but some things suggest it might not be, so I am going to refer you to a heart specialist to make sure it isn’t angina.

The GP has asked questions which are either completely open-ended or leave the patient free to describe exactly what happens within a directed area of interest. Clarifying questions have been used. While being reassuring, the GP expresses some concern about angina, and is clear about the exact reason for the specialist referral (for clarification).

Disease-centred versus patient-centred

An interview that uses lots of direct questions is often ‘disease centred’, whereas a ‘patient centred’ interview will contain enough open-ended questions for patients to talk about all of their problems and give them enough time to do so. This will also help to avoid the situation in which the doctor and the patient have different agendas. There can often appear to be a conflict if the patient complains of symptoms that are probably not medically serious, such as tension headache, while the doctor is focusing on some potentially serious but relatively asymptomatic condition, such as anaemia or hypertension. In this situation, a patient-centred approach will allow the patient to air all of his problems, and will allow a skilled doctor to educate the patient as to why the other issues are also important and must not be ignored. A GP may rightly refuse a demand for antibiotics for a sore throat that is likely to be viral, but should use the opportunity to educate and inform the patient about the true place of antibiotic treatment and the risks of excess and inappropriate use. The doctor needs to grasp the difference between the disease framework (what the diagnosis is) and the illness framework (what the patient’s experiences, ideas, expectations and feelings are), and to be able to apply both frameworks to a clinical situation, varying the degree of each according to the differing demands.

Judging the severity of symptoms

Many symptoms are subjective and the degree of severity expressed by the patient will depend on his own personal reaction and also on how the symptoms interact with his life. A tiny alteration in the neurological function of the hands and fingers will make a huge impression on a professional musician, whereas most others might hardly notice the same dysfunction. A mild skin complaint might be devastating for a professional model but cause little worry in others.

Trying to assess how the symptoms interact with the patient’s life is an important skill of history taking. A simple question such as ‘How much does this bother you?’ might suffice. It may be helpful to ask specific questions about how the patient’s daily life is affected, with comparison to events that many patients will experience. Box 1.5 illustrates some of the relevant areas.

Box 1.5 Areas of everyday life that can be used as a reference for the severity, importance or clarification of symptoms

Exercise tolerance: ‘How far can you walk on the flat going at your own speed?’, ‘Can you climb one flight of stairs slowly without stopping?’, ‘Can you still do simple housework such as vacuum cleaning or making a bed?’

Work: ‘Has this problem kept you off work?’, ‘Why exactly have you not been able to work?’

Sport: ‘Do you play regular sport and has this been affected?’

Eating: ‘Has this affected your eating?’, ‘Do any particular foods cause trouble?’

Social life: ‘What do you do in your spare time and has this been restricted in any way?’, ‘Has your sex life been affected?’

Medical symptomatology often involves pain, which is probably more subjective than almost anything else. Many patients are stoical and bear severe pain uncomplainingly whereas others seem to complain much more about apparently less severe pain. A simple pain scale can be very helpful in assessing the severity of pain. The patient is asked to rate his pain on a scale from 1 to 10, with 1 being a pain that is barely noticeable and 10 the worst pain he can imagine, or the worst pain he has ever experienced. It is also useful to clarify what the reference point is for ‘10’, which for many women will be the pain of labour. The pain scale assessment is useful in diagnosis and in monitoring disease, treatment and analgesia. Assessing a patient with pain is discussed in more detail in Chapter 9.

Which issues are important?

A problem for those doctors wishing to take the history in chronological order – ‘Start at the beginning and tell me all about it’ – is that people usually start with the part of the problem that they regard as the most important. This is, of course, entirely relevant from the patient’s viewpoint, and it is also important to the doctor, since the issue that most bothers the patient is then brought to attention. Curing disease may not always be possible, so it is important to be aware of the important symptoms since, for example, pain may be relieved even though the underlying cause of the pain is still present. It is very common for the doctor to be pleased that one condition has been solved, but the patient still complains of the main symptom that he originally came with.

A schematic history

A suggested schematic history is detailed in Box 1.6. There will be many clinical situations in which it will be clear that a different scheme should be followed. An important part of learning about history taking is that each doctor develops their own personal scheme that works for them in the situations that they generally come across. Nevertheless, it is useful to start with a basic outline in mind.

Direct questions about bodily systems

Within the variety of disease processes that may present to doctors, many have features that occur in many of the bodily systems which at first may not seem to be related to the patient’s main complaint. A patient presenting with back pain may have had some haematuria from a renal cell carcinoma that has spread and is the cause of the presenting symptom. For this reason, any thorough assessment of a patient must include questions about all the bodily systems and not just areas that the patient perceives as problematic. This area of questioning should be introduced with a statement such as ‘I am now going to ask you about other possible symptoms that could be important and relevant to your problem’. A list of such question areas is given in Box 1.7.

Box 1.7 Bodily systems and questions relevant to taking a full history from most patients. If the specific questions have been covered by the history of the presenting complaint, they do not need to be included again. If the answers are positive, the characteristics of each must be clarified

Cardiorespiratory

Chest pain

Intermittent claudication

Cough with or without sputum

Haemoptysis

Gastrointestinal

Abdominal pain

Dyspepsia

Dysphagia

Nausea and/or vomiting

Degree of appetite

Weight loss or gain

Bowel pattern and any change

Rectal bleeding

Jaundice

Genitourinary

Menstrual irregularity – women

Urethral discharge – men

Locomotor

Joint pain

Change in mobility

Neurological

Transient loss of function (vision, speech, sight)

Paraesthesiae

In addition, during any medical consultation, however brief, it is the duty of the doctor to be alert to all aspects of the patient’s health and not just the area or problem that he has presented with. For example, a GP would not ignore a high blood pressure reading in a patient presenting with a rash, even though the two are probably not connected. This function of any consultation can be regarded as ‘screening’ the patient. In health economic terms, a true screening programme for a particular disease across a whole population (such as for cervical cancer) has to be evaluated as being useful, economic and with no negative effects. However, once the patient has attended a doctor with a complaint, a simple screening process can be incorporated into the consultation with little extra time or effort. The direct questions (and full routine examination) encompass this screening function as well as contributing to solving the patient’s presenting problems.

Clarifying detail

One of the basic principles of history taking is not to take what the patient says at face value but to clarify it as much as possible. Almost all of the history will involve clarification but there are specific areas where this is particularly important.

Pain

Whenever a patient complains of pain, there should follow a series of clarifying questions as listed in Box 1.8. Of all symptoms, pain is perhaps the most subjective and the hardest for the doctor to truly comprehend. A simple pain scale has been described above. The other characteristics are vital in analysing what might be the cause of pain. Some painful conditions have classic sites for the pain and the radiation (myocardial ischaemia is classically felt in the centre of the chest radiating to the left arm). Pain from a hollow organ is classically colicky (such as biliary or renal colic). The pain of a subarachnoid haemorrhage is classically very sudden, ‘like a hammer blow to the head’. Some pains have clear aggravating or relieving factors (peptic ulcer pain is classically worse when hungry and better after food). Colicky right upper quadrant abdominal pain accompanied by jaundice suggests a gallstone obstructing the bile duct and a headache accompanied by preceding flashing lights suggests migraine. It is always worth making sure that any symptom of pain has been clarified in this way, and while some of the points will come out in the open-ended part of the history taking, others will need specific questions.

Box 1.8 List of clarifications for a complaint of pain

Drug history

At first glance, asking a patient what drugs he is taking would seem to be one of the simplest and most reliable parts of taking a history. In practice, this could not be further from the truth, and there are many pitfalls for the inexperienced. This is partly because many patients are not very knowledgeable about their own medications, and also because patients often misinterpret the question, giving a very narrow answer when the doctor wants to know about medications in the widest sense. The need for clarification in the drug history is given in Box 1.9. The drug history, almost more than any other, benefits from being repeated at another time and in a slightly different way. For example, in trying to define a possible drug reaction as a cause of liver dysfunction, it is not unusual to find that the patient has taken a few relevant tablets (such as over-the-counter non-steroidal anti-inflammatory drugs) just before the onset of the problem, and only remembered or realized it was important to say so when asked repeatedly in great detail.

Family history

Like the drug history, the family history would seem at first glance to be simple and reliably quoted. In general this is true, but it can be dissected into sections that will uncover more information. These are set out in Box 1.10.

Box 1.10 Detail of the family history

Are there any illnesses that run in your family?

Occasionally this will reveal major genetic trends such as haemophilia. More often there will be an answer such as ‘They all have heart trouble’.

Basic family tree of first-degree relatives

This should be plotted on a diagram for most patients, including major illnesses and cause and age of any deaths.

Specific questions about occurrence of problems similar to the patient’s

Ask the patient about items in the developing differential diagnosis, for example ‘Does any one in your family have gallstones/epilepsy/high blood pressure?’ if these seem a likely diagnosis for the patient under consideration.

Occupational history

It is always useful to know the patient’s occupation if they have one, as it is such an important part of life and one with which any illness is bound to interact. In some situations, a patient’s occupation will be directly relevant to the diagnostic process. The classic industrial illnesses, such as lead poisoning and other toxic exposures, are now extremely rare in developed industrial countries, but accidental exposure continues to occur. Other problems, such as asbestosis or silicosis, produce effects many years after exposure, and a careful chronological occupational history may be required to elucidate the exposure. For patients with non-organic problems, the work environment can often be the trigger for the development of the problem.

Alcohol history

The detrimental effects of alcohol on health cause a variety of problems and the frequency of excess alcohol use in Western countries means that up to 10% of adult hospital inpatients have a problem related to alcohol. To make an accurate estimate of alcohol consumption and any possible dependency, it is essential to enquire carefully and not to take what the patient says at face value, but to probe the history in different ways (Box 1.11). For documentation, the reported amount should then be converted into units of alcohol per week (Box 1.12). If the reported amount seems at all excessive then an assessment should be made of possible dependency for which the CAGE questions are very useful (Box 1.13).

Box 1.11 Probing the alcohol history

Doctor: Do you drink any alcoholic drinks?

Patient: Oh yes, but not much – just socially.

Doctor: Do you drink some every day?

Patient: Yes.

Doctor: Tell me what you drink.

Patient: I usually have two pints of beer at lunchtime and two or three on my way home from work.

Doctor: And at the weekend?

Paitent: I usually go out Saturday nights and have four or five pints.

Doctor: Do you drink anything other than beer?

Patient: On Saturdays I have a double whisky with each pint.

The first answer does not suggest a problem. Based on the figures in Box 1.12, the actual amount adds up to 70 units per week which clearly confers considerable health risks to this patient.

Box 1.12 Units of alcohol (1 unit contains 10 g of pure alcohol)

The units of alcohol can be determined by multiplying the volume of the drink (in ml) by its % alcohol by volume (abv) and dividing this by 1000. For example, 1 pint (568 ml) of beer at 3.5% abv contains: (568 × 3.5) / 1000 = 1.988 units.

It is important to bear in mind that alcohol strength varies widely within each category of drink, but here is a guide to the most common alcoholic drinks:

Standard-strength beer (3.5% abv): 1 pint = 2 units

Very strong lagers (6% abv): 1 pint = 3.5 units

Spirits (whisky, gin, etc., 40% abv): 1 UK pub measure (about 25 ml) = 1 unit

Wine (12%): 1 standard glass (175 ml) = 2 units

Box 1.13 The CAGE assessment for alcohol dependency

C – Have you ever felt the need to Cut down your alcohol consumption?

A – Have you ever felt Angry at others criticizing your drinking?

G – Do you ever feel Guilty about excess drinking?

E – Do you ever drink in the mornings (Eye-opener)?

Two or more positive answers could indicate a problem of dependency.

Retrospective history

The concept of retrospective history taking is a refinement of taking the past medical history and develops the theme of never taking what the patient says at face value. Many patients will clearly say that they have had certain illnesses or previous symptoms using medical terminology. This information may not be accurate either because the patient has misinterpreted it or because they were given the wrong information or diagnosis in the first place. This area becomes particularly important if any new diagnosis is going to rely on this type of information. For instance, in assessing a patient presenting with chest pain at rest, a past history of angina of effort will be considered a risk factor for acute myocardial infarction and will increase the likelihood of that as the current diagnosis. However, on closer questioning, it might become clear that what the patient was told was angina (perhaps by a relative and not even a doctor) was in fact a vague chest ache coming on after a period of heavy work, and not a clear central chest pain coming on during exertion.

Clearly the possibility of retaking the history for everything the patient says about his medical past may not be practical in the time available, but the possibility and value of doing this should always be borne in mind and can radically alter the developing differential diagnosis.

Particular situations

It is true to say that while there are many themes, patterns and common areas to history taking, and some areas of history taking might seem routine, the process of history taking for different patients will never be identical. There are some particular and often challenging situations that deserve some further description.

Garrulous patients

A new medical student will soon meet a patient who says a huge amount without really revealing the information that goes towards a useful medical history. This will be in marked contrast to some other patients who, from the first introductory question (e.g. ‘Tell me about what has led up to you coming here today’), will reveal a perfect history with virtually no prompting. A fictitious, but typical, history from the former type of patient is given in Box 1.14. When faced with such a patient, the doctor will need to significantly alter the balance of open-ended and direct questions. Open-ended questions will tend to lead to such a patient giving a long recitation but with little useful content. The doctor will have to use many more clear direct questions which may just have yes/no answers. The overall history will inevitably be less satisfactory but it is not possible to get the ‘perfect’ history in every patient.

Box 1.14 A typical ‘garrulous’ history

Doctor: Tell me about what has led up to you coming here today.

Patient: Well doctor, you see, it was like this. I woke up one day last week – I am not quite sure which day it was – it might have been Tuesday – or, no, I remember it was Monday because my son came round later to visit – he always comes on a Monday because that’s his day off college – he’s studying law – I’m so pleased that he’s settled down to that – he was so wild when he was younger – do you know what he did once …?

Doctor (interrupting): Can you tell me what did happen when you woke up last Monday?

Patient: Oh yes – it was like this – I am not sure what woke me up – it may have been the pain – no, more likely it was the dustmen collecting the rubbish – they do come so early and make such a noise – that day it was even worse because their usual dustcart must have been broken and they came with this really old noisy one …

Doctor (interrupting): So you had some pain when you woke up then?

Patient: Yes – I think it must have been there when I woke up because I lay in bed wondering where on earth there might be some indigestion remedy – I knew I had some but I am one of those people who can never remember where things are – do you know what I managed to lose last year …?

Doctor (interrupting): Was the pain burning or crushing?

Patient: Well, that depends on what you mean by …

Doctor (interrupting): Yes, but did you have any crushing pain?

The doctor gradually changes from very open-ended to very closed questions in order to try to get some information that is useful to building up the diagnostic picture – eventually a question is asked that just has a yes/no answer.

Analysing symptoms

The objective of the history and examination is to begin identifying the disturbance of function and structure responsible for the patient’s symptoms. This is done by analysis of the symptoms and signs leading to a differential diagnosis (a list of possible diagnoses that will account for the symptoms and signs, usually set out in descending order of likelihood). This list of possibilities is then often refined by the use of special investigations but, in up to 80% of patients, the likely diagnosis is clear after the initial history and examination. The process of analysis can be likened to detective work, in which the symptoms and signs are the evidence. When a medical student is first faced with the myriad of data gleaned on taking a history, he is often baffled as to how to start the analysis, but inevitably the process becomes easier as more medical knowledge is acquired. An analysis of symptoms from a medical student is more based on facts learned from textbooks, whereas an experienced doctor will tend to base the analysis more on patterns of disease presentation that they have encountered many times. While the analytical process is largely acquired through this type of experience, some principles can be described.

‘Hard and soft’ symptoms

A detective analysing evidence of a crime will put a lot of weight on fingerprint or DNA evidence and less weight on identification evidence. The same principles apply to analysing symptoms. A ‘hard’ symptom can be thought of as one which, if clearly present, adds a lot of weight to a particular diagnosis. A ‘soft’ symptom may be thought of as one which is either reported by patients so variably that its true presence is often in doubt, or one which is present in such a variety of conditions as to not be useful in confirming or refuting a diagnosis. Examples of these two groupings are given in Box 1.15.

Time course

A simple epithet states that the type of symptom suggests the ‘anatomy’ of the problem and the time course the ‘pathology’ of it. For instance, a vascular event such as a myocardial infarct, stroke or subarachnoid haemorrhage usually has a sudden onset, whereas something that gradually progresses or for which the onset cannot be exactly dated by the patient, such as weight loss or dysphagia, may be a malignant process. There are some pitfalls in this type of analysis which must be borne in mind to avoid confusion.

Disease processes that gradually progress may start off by being asymptomatic and the patient may only notice symptoms when they start to interfere with his lifestyle and activities. For example, exertional breathlessness in a largely sedentary patient may develop late on in a cardiorespiratory disease process, whereas a patient who actively exercises is likely to notice symptoms much earlier. This phenomenon is also seen where the relevant bodily organ or system has a lot of reserve and the symptom may only show itself when the reserve is used up. This could be true for a relatively chronic liver disease such as primary biliary cirrhosis apparently presenting acutely. The proverb of the ‘straw that broke the camel’s back’ is a good analogy of this sort of situation (a camel is steadily loaded up with straw until suddenly it appears that a tiny piece of straw is sufficient to make the camel collapse). In addition, the disease process may have a step-wise worsening rather than a linear decline, such as in a situation of multiple small strokes when the patient may not present until a single small stroke makes a big difference to his functional ability.

Pattern recognition versus logical analysis

It is important to realize that in some clinical situations the diagnosis may be clear based on previous experience, and in others the diagnosis has to be built up through a process of logical analysis of symptoms, signs and special investigations. The fact that the process of gaining information from symptoms, signs and special investigations is never completely exact must also be borne in mind so that the patient with an atypical presentation is not assigned the wrong diagnosis. The area of medicine that probably most often uses pattern recognition is dermatology, but recently skin biopsies are used much more to clarify diagnoses that were previously assumed. A patient presenting with chest pain and signs of underperfusion may easily be thought to be having a myocardial infarction but a brief history of the character of the pain (tearing and going through to the back) may prompt a search for a dissecting aortic aneurysm.

Negative data

An experienced history taker will begin the analysis from the outset of the clinical encounter. This means that during the initial process and without the need for so much later review, questions can be asked for which a negative answer is as important as a positive one. These questions are usually very specific and direct, often with a yes/no answer. A patient whose presenting complaint is exertional chest pain can immediately be asked if the pain is worse on increased exertion and how long a period of rest is needed to relieve it. Pain that is not predictably produced by exertion and is not reliably relieved by rest may well not be angina pectoris. However, it remains very important that interjected questions of this type do not spoil the flow of the patient’s story.

What does the patient actually want?

If a patient comes to a doctor with a long history, it is always worth trying to find out why he has come for medical help and what he actually wants from the consultation. There may be various scenarios as listed in Box 1.16. It is always worth trying to find out which might apply to the patient, because it sets the scene for giving advice and treatment, particularly if an exact diagnosis or a complete treatment cannot be provided. It is often much easier to reassure a patient that there is nothing seriously wrong than to give him an exact diagnosis or fully relieve his symptoms.