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Abstract:
Old age is the most common time in life to develop
epilepsy. Diagnosis and treatment of disease
in elderly people needs special capabilities.
There is no exception for epilepsy in this regard.
According to research a high incidence of convulsion
in aged people is increasing. Average life expectancy
at birth has increased by 20 years since 1950,
to 66 years and is expected to extend a further
10 years by mid-century.
This
demographic triumph means that the number of
older people will increase from about 600 million
in 2000 to almost 2,000 million in 2050. The
provision of both health and social care to
older people is a necessity.
Incidence
of epilepsy in the elderly (over 80 years old)
is 140 in 100,000. Diagnosis of this disease
is so important in old age people because problems
such as Transient Ischaemic Attack (T.I.A),
cardiovascular problems, and transient confusion
in patients with dementia, neurogenic syncope,
and Transient Global Amnesia (TGA), can mimic
or be feigned by it. Sometimes the picture of
symptoms is different between young and older
persons; and may even appear as non-convulsive
status epilepticus (NCSE). On the other hand,
senile changes that cause epilepsy in elderly
must be subject to further studies.
Treatment
and selection of drugs in elderly people needs
special consideration. Different changes such
as metabolic changes, changes in brain tolerance
to drugs and side effects, changes in function
of bodily organs, associated diseases and consumption
of various drugs at the same time, provide many
challenges during the treatment process. The
knowledge regarding the importance of epilepsy
in elderly is increasing. Nowadays, senile affairs
and the problem of elderly people is regarded
seriously and consequently there is hope that
in the near future the knowledge and understanding
about effective factors regarding epilepsy in
old age persons, such as senile changes of brain
and its effect on epilepsy, will be expanded
and increase.
Key
Words: Epilepsy; Elderly; Diagnosis; Treatment.
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Introduction
Average life expectancy
at birth has increased by 20 years since 1950, to
66 years, and is expected to extend a further 10 years
by mid-century. This demographic triumph means that
the number of older people will increase from about
600 million in 2000 to almost 2,000 million in 2050.
The provision of both health and social care to older
people is a truth.
Nowadays, through use
of health/treatment interventions and expansion of
science, the age of people in societies has been increased.
Due to the increase of age, diseases of this population
will have special importance. Old age is the most
common time in life to develop epilepsy. Making a
secure diagnosis can be difficult, and piecing together
an accurate picture of events may take some time.
Neurological diseases have a special place among different
diseases in elderly. Epilepsy is one of these diseases
that may be developed in this age for the first time,
or had been prolonged from previous years to this
special senile condition. Epilepsy, besides physical
effects, can cause severe psychological impacts in
elderly people, and in some ways, affect quality of
life. There are reports that incidence of epilepsy,
for the first time, in this age range, is increasing
(Bergey, 1994). After initial incidence in the first
years of life, for a few decades, the incidence up
to 65 years of age will be stable. After 65 years
of age, abruptly, the incidence of epilepsy will be
increased (Hauser , 1992).
Due to organic factors,
some of which are indicated below, epilepsy in elderly
people can appear as a primary or secondary condition:
| 1) |
Metabolic
disorders such as hyperglycemia, hypoglycemia
, hyponatremia , uremia , hypocalcemia. |
| 2) |
Sudden
interruption of drugs like barbiturates and benzodiazepines. |
| 3) |
Intaking
of drugs which increase the risk of incidence
of epilepsy such as phenotiazins , tri-cyclic
antidepressants , theophylline , antibiotics. |
| 4) |
Infections
: meningitis , pneumonia , urinary infection. |
| 5) |
Trauma |
| 6) |
Cerebrovascular
Accident (CVA) |
| 7) |
Dementia |
| 8) |
Neoplasm |
Primary or idiopathic
epilepsy make approximately 50% of epilepsy in old
age people. Incidence of epilepsy in elderly, in different
studies, have been mentioned 100-140 per 10/0000 (Hauser,et
al,1993). In one study the incidence of acute convulsion
(for the first time) in the age more than 65 years,
have been depicted 24-30 % (Sanders,et al, 1990).
Also, 30% of convulsion in elderly people have status
convulsion, which is twice of this condition in lower
ages (Towne, et al, 1994). Status convulsion is so
important in emergency cases in neurology science.
Diagnosis of epilepsy in elderly
people
Because epilepsy in old-age
persons can mimic other diseases, its diagnosis is
difficult. Unfortunately, in most cases the diagnosis
is not correct. Fortunately, nowadays, knowledge in
this regard has increased and medical/ therapeutic
personnel have more information and research on the
topic.
The primary evaluation of
epileptic persons is the same as for other ages. A
precise history must be taken from the patient and
his/her family. Exact questions regarding type of
seizures and risk factors such as head trauma (hard
or soft) should be asked. The incidence of complex
partial epilepsy in old ages is higher and after 60
years of age the rate of incidence, is abruptly increased.
This is in contrast with the young ages, that is,
the generalized, tonic-colonic epilepsy has the highest
rate of incidence. On the other hand, it is confirmed
that the postictal condition in elderly people differs
from young people. This condition is longer in older
persons and sometimes its duration is a few days or
even many weeks and, mostly presents as loss of memory,
behavioural disorder, aphasia or motor (movement)
disorder. Incidence of epilepsy with non-specific
signs in the elderly, is so important:
| 1) |
One of these
signs is behavioral disorder which is produced
intermittently, especially when it is accompanied
by cognitive disorders. Sometimes patients are
referred with symptoms of dementia, and because
the incidence of it is high in old-ages, the diagnosis
of epilepsy may be missed. |
| 2) |
Neurogenic
syncope: On the whole, diagnosis of neurologic
syncope is not problematic. With case history,
and assessment of postictal condition, the type
of epilepsy can be differentiated. |
| 3) |
Cardiac diseases
include: intermittent arrhythmia such as atrial
fibrillation (AF), supra-ventricular tachycardia,
Stoke Adams attack can result in syncope. Sometimes
syncope is followed by convulsions. After treatment
of cardiac disease, the syncope will be treated. |
| 4) |
Vascular
diseases of the brain such as T.I.A: In this case
accompanying of other neurologic signs like hemiparesis,
hemiplegia, hemisensory or parastesis could be
assigned as a diagnosis of TIA. In cases with
motor signs the diagnosis is simple but if the
sensory signs exist on their own, diagnosis of
epilepsy will be difficult (Penfield et al, 1959).
In these cases, EEG especially can be helpful
and in 10% of cases, will be positive (Devinsky,
et al, 1988). |
| 5) |
Drop-attack:
In this condition the patient may fall abruptly
immediately after standing and sometimes drops
objects. Sometimes, falling itself causes injuries. |
| 6) |
Epileptic
aphasia: one of the problem in the diagnosis of
epilepsy in T.I.A is the epileptic aphasia; especially
in patients with the history of C.V.A., at least
once(Rosenbaum et al,1986). The process of producing
aphasia can help us to differentiate it from T.I.A.
In epileptic aphasia there is no neurological
sign. EEG is helpful in this regard. |
| 7) |
T.G.A: Beginning
of memory loss is abrupt in these diseases and
short term memory is mostly affected. In T.G.A
the patient asks the same questions sequentially.
The average time for one T.G.A is 7-9 hours (Caplan,et
al,1985). During the attack, EEG is normal (Gloor,
in press). Generally, it is presents onece in
a lifetime, but sometimes it happens more than
once. |
| 8) |
NCSE: these
attacks are present as mild confusion amnesia,
or severe loss of consciousness. Sometimes it
is prolonged, for hours, days or months. The main
cause of NCSE is the cessation of Benzodiazepines,
so the history of drug consumption can be helpful.
EEG is also useful. Opiate consumption can produce
and cause NCSE and delay the diagnosis of epilepsy
for a long time. |
Para clinical affairs
Because the toxic and metabolic
aspects are the main and common causes of epilepsy,
each patient who has epilepsy for the first time,
must be evaluated for cell blood count (CBC), Biochemical
tests such an electrolytes, calcium and liver and
kidney tests. One of the important tests is EEG which
must be performed.
EEG is helpful in the diagnosis
of disease and type of epilepsy. In elderly people,
there is a change in EEG which is not considered as
epilepsy. These changes are: slowing and decreasing
of EEG voltage especially if these changes are of
the diffuse type.
CT-Scans and Magnetic Resonance
Imaging (MRI) are the remaining tests for elderly
people with a history of the first (or one) epileptic
attack. These are helpful in diagnosis of brain vascular
and tumoral problems, which are a common cause of
epilepsy in elderly persons.
Assessment of cerebrospinalfluid
(C.S.F) is helpful, especially when epilepsy is associated
with fever or whenever there is suspicion of the presence
of meningitis.
Treatment
The main goal of treatment
is prevention of epileptic attack recurring. So, whenever
there is any reason for recurrent epilepsy, therapeutics
must be commenced. Pateints with epilepsy with clear
and exact symptoms, such as disturbance in electrolyte
concentration, need to take anti-convulsive drugs
so that resumption of seizures can be avoided.
According to several factors
the probability of epilepsy may be predicted in elderly
people with :
1) Movement problems after attack (postictal paralysis)
2) Partial seizure
3) Family history
4) Abnormal EEG
5) Abnormal neurologic examination.
All of these factors contrinute
to an increased incidence of epilepsy in such patients.
In elderly people, due to
the changes in all systems of the body, drug consumption
should be considered carefully; such as:
| 1) |
Digestive
system: Mucous atrophy in this system due to the
changes in serum levels and drug uptake. |
| 2) |
Kidney function:
function of kidney is decreased after 20 years
of age and at 80 years old is halved. So, drugs
which are exhausted by the kidney may be increased
at the serum. |
| 3) |
Liver
function: lack of liver function declines and
drugs which are metabolized in liver, consequently
the serum level of this drug is increased. |
| 4) |
Increases
of lymph tissues in elderly people cause changes
in serum levels. |
| 5) |
Albumin serum
decrease: drugs which are bond with albumin (like
phenytoin, valporate sodium) show toxicity symptoms
sooner. |
| 6) |
Increase
of half life of drugs in elderly people. |
| 7) |
Brain atrophy
and, consequently, production of further sleepy
status is aqffected by anti-convulsive drugs. |
Drug application
Today there is a vast variety of drugs for treatment
of epilepsy in elderly people, especially since 1993
and with the introduction of a new generation of anticonvulsive
drugs, new possibilities have been supported. Among
various old drugs, carbamazepin, alone or with valporate
sodium, provides first step (frontline) treatment.
Among the newer drugs, gabapentin and lamotrigine
have special importance and the consumption of tiagabine
and topiramate is increasing.
Carbamazepin
Carbamazepin is well tolerated by old age persons.
It has low side effects. Despite phenytoin it has
no great fluctuation in serum levels. According to
the physiologic condition of elderly people, consumption
of it during 24 hour must be twice only. It is mainly
used in partial epilepsy.
Valporate
Valporate has been used for more than 20 years. In
comparison with carbamazepin and phenytoin it has
a more effective spectrum, and sois useful in primary
tonic-colonic epilepsy treatment. It is also useful
in secondary generalized epilepsy (Mattson, et al,
1992). Considering its short half life, this drug
should be delivered in several doses. Its main side
effects are: tremor, weight increase, hair loss.
Gabapentin
Gabapentin is useful in partial epilepsy, and causes
increase in gamma aminobutyric acid (GABA) levels
of the brain. It has a 9 hour half life and must be
used three times per day. It does not case any change
in the outflow of urine, and has no great side effect
and can be tolerated well by elderly people.
Lamotrigine
Lamotrigine acts as a glutamate neurotransmitter;
and is metabolized by the liver. 10% of it, is discarded
by urine. It is useful in treatment of partial epilepsy.
It has a 24 hour half life, so, must be used in two
doses.
Topiramate
Topiranate is used to assist in treatment of partial
epilepsy. It has a 24 hour half life and must be used
in two doses; it has low side effects and can be tolerated
by elderly people. The main outflow for it, is via
the kidney.
Tiagabine
Specifically, Tiagabine inhibits reuptake of GABA
and increases its concentration in the brain. It is
useful in treatment of partial epilepsy. It is metabolized
in the liver. It has a nine hour half life and must
be used with different doses.
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