The appropriate and timely
diagnosis and management of older persons with
impaired cognition can make a critical difference
to their overall health and ability to function
independently.
Common causes of impaired cognition in older persons
can be broadly classified into delirium, dementia
and depression.
Delirium is an acute or sub-acute
change in the mental state that is common in frail
older persons. It can arise as a result of a myriad
of conditions that include infections, strokes,
medication side-effects, heart failure, abnormal
metabolic states (e.g. poorly controlled diabetes
mellitus, abnormally low or high sodium levels).
It is known that persons who suffer from delirium
are often seriously ill. They are at greater risk
of developing complications from their acute illness
and may be at increased risk of developing dementia
later on.
It is important for older persons with a recent
change in mental state to be assessed by a medical
practitioner at the earliest possible instance,
as many of the causes of delirium are amenable
to medical interventions.
Dementia affects 4 to 13% of
older persons above the age of 65, depending on
the system of classification that is being applied
to make the diagnosis. While it is common for
older persons to suffer from some degree of memory
loss, it does not mean that memory loss equates
dementia. It is also equally important to realize
that ageing does not inadvertently lead to dementia
and that significant memory loss is not "normal"
in older persons. Persons are diagnosed to have
dementia when they have a sustained loss of intellectual
abilities and memory that is of sufficient severity
to affect their ability to function in their usual
manner in everyday life.
As much as 3 to 10 % of persons presenting with
features that are consistent with a diagnosis
of dementia actually have conditions that are
potentially reversible. These may include brain
tumours, blood clots within the brain or metabolic
disorders. Even when the cognitive syndrome is
not reversible, modalities exist that may help
to retard the progression of a proportion of dementia
sufferers.
In addition, apart from the
decline in intellectual function, dementia sufferers
often have significant neuro-psychiatric and behavioural
problems that result in severe stress to their
care-givers and may place the sufferers and their
loved ones at risk of harm.
Early recognition of this cognitive
syndrome, coupled with proper assessment and intervention
may result in improvement in outcomes as well
as a reduction in carer stress and an improved
quality of life for the patients as well as their
care-givers.
Depression
is a common example of the non-specific and atypical
presentation of illness in older persons. Features
suggestive of depression in older persons may
arise from a range of treatable physical illnesses,
but may also be the presenting manifestations
of a major depressive illness. Depression in older
persons is thus often under-diagnosed.
Recognition and appropriate
management of interactions between the symptoms
and signs of depression secondary to physical
illnesses and those caused primarily by psychiatric
disorders can help prevent medical morbidity and
result in improved quality of life.
Examples of physical illnesses
that may manifest with depressive symptoms include
heart failure, metabolic conditions such as hyperthyroidism
or hypothyroidism, abnormal sodium levels, chronic
pain syndromes or even medication side effects.
For primary affective disorders,
effective strategies for intervention that include
pharmacotherapy and non-pharmacological means
are readily available. |
