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Contents:
Classification of epileptic seizures in adults
Incidence and prevalence
Drugs of choice for the treatment of epilepsy
Counselling points for patients with epilepsy
Who needs referral?
Anti epileptics and oral contraceptives
Pregnancy
Monitoring tests required with patients with antiepileptic drugs
Epilepsy and Driving.
Some references regarding epilepsy and general practice

Classification of epileptic seizures in adults

1. Partial seizures

A. Simple partial (no alteration of consciousness)

Results from focal epileptic discharge in a localised part of the brain. A simple partial motor seizure begins in the motor cortex. When it spreads sequentially through the motor strip, it is called a Jacksonian march.

B. Complex partial (with alteration of consciousness)

A prodrome is common and automatisms are seen in 90% of patients, with post ictal drowsiness in 75% of patients.

C. Partial becoming secondarily generalised (secondary generalised tonic-clonic seizures)

A partial seizure which spreads to the entire brain to produce a convulsion is a secondary generalised seizure.

2. Generalised seizures

A. Absence

A brief episode of unconsciousness with little or no motor accompaniment. (petit mal).

B. Myoclonic

Usually single, sudden, uncontrollable jerks.

C. Clonic

D. Tonic

E. Tonic-clonic

An epileptic attack in which there is loss of consciousness and generalised tonic then clonic muscle contractions.

F. Atonic

An attack in which there is generalised loss of muscle tone, and the patient falls down. Consciousness is not lost.

[Index]

Incidence and prevalence

NB there is an increased incidence of sudden unexpected death (x6) not entirely due to status epilepticus.

[Index]

Drugs of choice for the treatment of epilepsy

 
 

1st choice

Probable second choice

Last resort

Partial +/- SGTCs*

Carbamazepine
Sodium Valproate

Phenytoin
Vigabatrin
Lamotrigine
clobazam

Phenobarbitone
Primidone

Primary Generalised
Tonic-Clonic

Sodium valproate

Lamotrigine
Carbamazepine
Phenytoin
Clobazam

Phenobarbitone
Primidone

Absence

sodium valproate
Ethosuximide

Lamotrigine
Clobazam

 

Myoclonic

sodium valproate

Lamotrigine
Ethosuximide
Clobazam

 

*SGTCs=Secondary generalised tonic clonic seizures

[Index]

Counselling points for patients with epilepsy

1. Poor compliance is the most common cause for treatment failure
2. Patient must not run out of medication
3. Continue antiepileptics throughout illness, take an extra tablet if vomiting occurs soon after taking a tablet.
4. Medication should be taken regularly, as missed doses may provoke seizures
5. Encourage the use of a seizure diary.
6. Counsel patients on the use of contraceptives
7. Alcohol

8. Encourage patient to report side effects
9. British epilepsy Association

[Index]

Who needs referral?

Reasons for referral
a. To confirm the diagnosis

b. Choice of treatment is changing all the time therefore up to date opinion is required

c. Advice about driving, employment, schooling etc..
Most common complaint of patients is lack of information

d. Patients with special circumstances
e.g. pregnancy(see later)

e. Patients with continuing seizures

Diagnosis must be reconsidered

20% of patients with drug-resistant epilepsy have emotional attacks or non epileptic attacks.

Use of video telemetry and EEG are invaluable

[Index]

Anti epileptics and oral contraceptives

The effectiveness of both combined and progestogen only contraceptives may be considerably reduced by interaction with drugs that induce hepatic enzyme activity.

Anticonvulsants that induce hepatic enzyme activity:-

Loss of efficacy does not appear to be a problem with:-

However with the introduction of all anticonvulsants the patient should be asked to report any changes in the menstrual cycle

Family Planning association advises that in women who are unable to use an alternative form of contraception that a 50microgram pill be used.

If breakthrough bleeding occurs despite this either increase the dose of oestrogen or use a different form of contraception

Some feel that an additional form of contraception should be used, others feel that this is only necessary when adjustments are made in the anticonvulsant dose.

Depo-provera

No problems reported by the manufacturers

[Index]

Pregnancy

 
The risk of major malformations, minor anomalies and dysmorphic features is x2-3 higher in infants of mothers with epilepsy who receive treatment with epileptic drugs compared with the risk in infants of mothers without epilepsy
A possibility exists that some of the risk is caused by a genetic pre-disposition for birth defects inherent in certain families and therefore genetic counselling may be required
Possibilities for prenatal diagnosis of major malformations should be discussed. High resolution scanning can be done at 16-22 weeks gestation.
The effects of tonic-clonic seizures are not well studied but they may injure the mother and may result in miscarriage
All women contemplating pregnancy should take folic acid 5mg/day
I thepatient has been seizure free for at least 2 years, withdrawal of anticonvulsant should be considered
If anticonvulsant treatment is necessary then a switch to monotherapy may be necessary
The lowest dose and plasma level should be used.

[Index]

Monitoring tests required with patients with antiepileptic drugs

Drugs/Drug group Monitoring required

 
Drugs/Drug group Monitoring required
Carbamazepine Check blood levels only if there are continuing seizures or side- effects or to check compliance. FBC an LFTs before treatment and then regularly.
Phenytoin Check blood levels only if there are continuing seizures or side-effects or to check compliance. FBC an LFTs before treatment and then regularly. Check folic acid levels every six months
Barbiturates Check blood levels only if there are continuing seizures or side-effects or to check compliance
Valproate FBC an LFTs before treatment and then regularly. Blood concentrations are not clinically useful
Lamotrigine
Gabapentin Vigabatrin
Clobazam
No routine motoring is required

If a patient is well controlled there is no reason to check levels and if they are checked do not increase dose just to get it within the therapeutic range!!!

[Index]

Epilepsy and Driving.

The law and medical fitness to drive--a study of doctors' knowledge.
Doctors' knowledge on laws and recommendations regarding fitness to drive in certain medical conditions by a questionnaire survey. The results show the poor knowledge of doctors on several aspects of fitness to drive.
Postgrad Med J 1992 Aug

Regulations updated in 1994

Licence may be granted for 1,2 or 3 years provided

a) Free from any epileptic attack during the period of 1 year prior to the date of issue

OR

b) Nocturnal attacks only for 3 years

AND

c) Driving is not likely to be a source of danger to others

Licence may be changed to a 'till 70' if 6 years seizure free.

Medical Advice

Must be quite clear

1. Patient must be told he has epilepsy and that the law will prevent him from driving.

2. Emphasise to the patient that he must inform the DVLA.

3. Continued driving is illegal and may invalidate insurance cover.

4. Doctor has no legal responsibility to inform the DVLA

Must keep a written record

Confidentiality

A doctor should observe the code of professional conduct

GMC recognises that confidentiality may be breached where in the public interest failure to do so may place the patient or some other person at risk of serious harm or death.

In the first place the doctor must advise the patient to inform the DVLA

Subsequently he should challenge the patient and inform him that the doctor will have to inform the DVLA and WHY. This must be documented

If the patient does not inform the DVLA then the doctor should now do so.

If the doctor is aware that the DVLA had revoked the licence but the patient continues to drive the doctor may inform the police

Withdrawal of anticonvulsants.

There is a 40-50% risk of seizure recurrence in the succeeding 2 years

Most commonly as drugs are reduced and for six months after they have been stopped

Therefore under these circumstances it is advisable that the patient does not drive whilst the dose is being reduced and for six months after. But this is not enforced by the DVLA not is it a legal requirement.

Patients should also be aware that if they do have a seizure they will then be barred for a year after their last seizure

Isolated seizure

Defined as one or several seizures occurring in less than 24 hours

Patient must inform the DVLA

The licence will normally be revoked for one year or seizure free for 12 months.

If the seizure has been provoked e.g. drug abuse then the cause may be more relevant

Vocational drivers

Must be free

1. Epileptic attacks for >10years

AND

2. Have not taken anticonvulsants for 10 years

AND

3. Do not have a continuing structural cause.

[Index]

Some references regarding epilepsy and general practice

BJGP review Thapar: Care of patients with epilepsy in the community. BJGP Jan 1996

Literature study using Medline and Epidata

Specific problems and difficulties of managing patients with epilepsy in the community can be categorized as :

1. Lack of systematic follow up
Many reviews suggest that patients are not regularly followed up by either their GP or the hospital. The reasons for this haven't been explored and the effectiveness of systematic follow up needs to be researched.

2. Inappropriate polypharmacy
Studies show that between 35 to 60% of patients are on more than one drug
Optimum seizure control can be achieved for 70-80% of patients.
Polypharmacy increases side effects, may not be efficacious, reduces compliance and makes monitoring more difficult

3. Pt non compliance
50-70% of patients are compliant with med. from pt reporting and blood monitoring
Patients often decide to not comply due to stigma associated with treatment.
Need to discuss compliance and the possibility of stopping treatment with patients.

4. Failure of GP - pt communication
Studies have shown communication to be suboptimal. Many patients feeling they require more in formation than is given by their GPs

5. Low levels of pt knowledge
One study suggested that patients with epilepsy had the same knowledge about their condition than controls!!

Barriers to effective community care

1. Oganisational barriers
Computer searches fast but may be inaccurate e.g. some patients are taking anticonvulsants for conditions other than epilepsy
Notes review and interview, more time consuming
Call recall is often difficult and defaulters may be the most in need of follow up
Practice based epilepsy specialist nurses are advocated but a costly resource.

2.GP related barriers.
Reports suggest that most GPs feel that epilepsy is a complex disorder to manage.

3. Patient related barriers
Stigma felt by patients is often greater than the stigma enacted upon them by others.
Stigma increases with the severity of the illness
Stigma increases withdrawal and reduces attendance at special epilepsy clinics
Some patients do not have confidence in their GPs management of patients.

Initiatives to improve care for patients with epilepsy in the community
Local initiatives
Very little work on:
Practice based clinics
Epilepsy specialists nurses working in GP practices
Liaison nurses, between prim and sec care but also as an information base for GPs
Guidelines have been produced in certain regions e.g. by the Irish RCGP

National initiatives

Two recent initiatives sponsored by Wellcome
1. Epilepsy task force
multidisplinary group and patients group-s
Aims
to raise public awareness
lobby for appropriate primary and secondary care provision
establish guidelines and minimum standards for hospital OPD services

2. Epilepsy liaison nurse programme
Ran for a year in areas where there were specialised clinic
Helped GPs manage their patients
Helped GPs set up clinics and audit their care
Have not been fully evaluated


Epilepsy monitoring and advice recorded: GP's views, current practice and pt's preferences GP study of 37 GPs and 283 patients with epilepsy. BJGP 1996,46,11-14 Risdale et al
The majority (61%) of pt preferred their care to be supervised by their GPs
GPs reported that patients should be reviewed every 6 months (median 14 months)
GPs felt that a record should be made in the notes of the following in all patients:
Information % of notes with information recorded
Driving regulations 46
Drug side effects 9
Self help groups 3


35% of patients reported not getting enough advice.

A general practice records audit of the process of care for people with epilepsy.

 


AIM: The study was designed to examine the process of care for people with epilepsy through a region-wide audit of general practitioner records. METHOD: General practitioners in 31 randomly selected general practices in one UK health region undertook a notes audit for all patients identified as having active epilepsy (patients who had had seizures in the last 2 years, or were currently seizure-free but on antiepileptic medication). A standard pro forma was used to collect information relating to diagnosis, drug treatment, and primary and secondary care contacts. RESULTS: Recording of information in the notes was generally good, but poor for some key items essential to the effective management of the condition; results suggest that a number of recommendations about provision of care for epilepsy are not being met: in particular, EEG and CT investigations often appear poorly directed; prescribed antiepileptic therapy is not always optimal; significant numbers of patients are being treated in hospital by non-neurologists; there is little evidence of any regular review being undertaken by general practitioners of their patients with epilepsy; and counselling about the non-clinical aspects of epilepsy often appears inadequate. CONCLUSIONS: Despite recommendations in a number of recent reports, gaps and inconsistencies in epilepsy care persist, both at the primary and secondary level. The means by which such shortcomings can be reduced (e.g. by specialist epilepsy nurses working across the primary-secondary care interface) should now be systematically examined. The study has highlighted a need for evidence-based guidelines which span the primary-secondary care interface and clarify the contribution of the various practitioners involved in the provision of care for people with epilepsy.

Jacoby A Br J Gen Pract 1996 Oct 46


Francisco Machado 1/4/1997

 
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