How Our Life History Informs a Diagnosis of Dementia
It’s standard practice when we go to a doctor with symptoms that require a diagnosis; the physician turns detective. They look at the clues, our physiological, psychological and social functioning and any changes that have occured over time. They carry out tests and take a history that they hope will pinpoint the cause of the illness.
When people present with dementia-type symptoms, taking a history is not always easy. Often, a reliable witness has to be tracked down who can give accurate information. Sometimes a spouse or sibling will be able to shed light on the patient’s current problems, such as the changes in their behavior, the changes in their memory, their deficits in daily functioning. The doctor needs to know how long these changes have been going on for and if they have progressed.
Taking a history can be difficult. The doctor’s office or clinics in hospital settings can cause stress. The patient and their loved one or caregiver may need to be encouraged to give focus to incidents of disorientation, forgetfulness, misplace objects, organizing tasks (executive functioning). The person with dementia may not recognise familiar friends and relatives, buildings or places. Their moods may have slowly undergone dramatic changes over a given period of time. It is like a big jigsaw. Each piece of history helps makes the picture of what is happening clearer.
For instance, when my father’s memory failed dramatically it was as a result of a small stroke. Amongst other things, he thought my sister lived and cared for her children alone (she had in fact remarried 13 years earlier and her children were grown up). He held that belief for a number of weeks until he recovered, but then he had another stroke following which he deteriorated significantly. His medical history included a diagnosis of congestive cardiac failure, high blood pressure and significant renal failure A previously active, social man was felled by disease. His diagnosis was that his dementia was vascular in origin. His medications and subsequent treatments were geared to that diagnosis.
A clinician as medical detective, has to determine whether any medical or psychiatric factors preceded the onset of syptoms. Head injury is a risk factor for Alzheimer’s disease, as is age. The older the patient the more likely a diagnosis of Alzheimer’s. A history of apathy may be a feature of Alzheimer’s or may be a symptom of a psychiatric illness such as depression. Seizures may be caused by the brain damage of Alzheimer’s or it may be the patient has a tumor or metabolic disorder. Previous drug treatments may give the physician the clue to causation or this may be a new symptom.
Diagnosing diseases accurately is not a simple task. It is easy to see why training takes many years and why teams of clinicians are required, each with their own speciality for us to know what is wrong and how best to treat it.