Insects Unlocked

Original Neurosciences, Nobel Medical College, Biratnagar Corresponding author Dr

Original article

Kafle DR1 Shah SP 2

Institute of
Neurosciences, Nobel Medical College, Biratnagar

Corresponding author

Dr Dilli Ram Kafle

Nobel medical College,
Kanchanbari,Biratnagar, Nepal

Email:[email protected]

 ABSTRACT

Introduction

Epilepsy is a common disorder. About
three quarter of newly diagnosed people achieve remission after starting
treatment and almost a quarter develop drug-resistant epilepsy. About one quarter
of patients with first unprovoked seizure will have recurrence in the first
year while about one third of patients with a first unprovoked seizure will
have further seizures within five years.

Objective

The aim of the study was to find out
the risk of recurrence of seizure after a first unprovoked seizure in Nepalese
population.

Methodology

It is a Descriptive Cross-sectional
study which was conducted at Nobel Medical College from December 2014 to
November 2017

Results

 Eighty six patients participated in our study.
Recurrence of seizure occurred in 21(24.4%) patients within the study period of
3 years. Having an abnormal EEG, history of status epilepticus, a family
history of seizure and abnormal neuroimaging predicted further seizure
recurrence. Starting an antiepileptic after first seizure did not predict
further seizure recurrence.

Conclusion

Epilepsy is a common problem in the general population. Almost
fifty percent of the patients with first seizure had identifiable cause.
Recurrence of seizure was observed in almost a quarter of patients within the
study period of three years.

Key words: Epilepsy,
seizure recurrence, Electroencephalography

 

 

INTRODUCTION

The incidence of single seizure
in general population is about 5%, whereas epilepsy develops in 1-2% population.1 Epilepsy
is defined as 2 or more episodes of unprovoked seizures 24 hours apart. 2 Most
of the studies have shown that approximately one third of patients with single
seizure will experience a second one.3, 4

 The risk of recurrence among those patients who
have a first seizure seems to vary which may be explained by differences in
study design or differences in the characteristics of the study groups. About
35 percent of patients with a first seizure have a second recurrence within the
subsequent three to five years.5-7

                                       

This study addresses the
influence of various factors on recurrence of a single unprovoked idiopathic seizure
with regards to duration of seizure, family history of seizure, EEG finding and
use of anticonvulsant medication. 

 

METHODOLOGY

All the patients presenting with first seizure
at Nobel medical College from December 2014 to November 2017 participated in the
study. Detailed information regarding age, sex, time
from onset of seizure and seeking medical help or starting antiepileptic medication,
time of the occurrence of seizure, abnormal physical examination and family
history of seizure were obtained. The patient’s seizures were categorized
by etiology 8   as idiopathic (seizures in the absence of a
brain insult) or remote symptomatic (seizure in individuals with a
prior history of CNS insult) such as head trauma, cerebrovascular accident 9,
central nervous system infection 10  
or static encephalopathy from birth .11, 12 

 

The definition
of single seizure included status epilepticus  and clusters of seizures
(2 or more) in the same 24-hour period. Patients with   acute symptomatic
seizures were excluded from the study.

 

Neuroimaging
(Either CT scan or MRI of the brain) and Electroencephalography were done in
all patients presenting with seizure. Informed consent was taken from all the
patients. Ethical clearance for the study was obtained from the Institutional
Review Board.

 

 

 

 

 

 

 

 

RESULTS

The demographic
profile of the patients and their clinical characteristics are presented in table
1.

Table 1: Demographic profile of the study population Baseline Data (n=86)

Men
Women

61(71%)
25(29%)

Age of
Patients(Yrs)

34±16.7

Seizure type (Focal+
Secondarily generalized)
Generalized

21(24.4%)
65(75.6%)

Age at onset
of seizure

34±17

Duration of
seizure before starting treatment(In months)

5±4

Family
History of epilepsy

18(21%)

History of
status epilepticus

14(16.3%)

Aura

17(19.8%)

Recurrence of seizure
   No recurrence of seizure

21(24.4%)
65(75.6%)

Medication
               Monotherapy:
              Polytherapy

 
70(81.4%)
0

Compliance
with medication
Compliant
Noncompliant

 
79(91.9%)
7(8.1%)

Electroencephalography
      Normal
      Abnormal

 
50(58%)
36(42%)

Neuroimaging
(CT or MRI)
             Normal
            Abnormal

 
40(46.5%)
46(53.5%)

Documented
precipitant for
seizure

40(46.5%)

 

Eighteen (21%)
patients reported having a family history of seizure. Electroencephalography
was normal in 50 (58%) patients and abnormal in 36 (42%) patients. Status
epilepticus was seen in 14 (16.3%) patients. Either CT scan or MRI of brain was
done in all patients presenting with seizure. Neurocysticercosis was diagnosed based
on neuroimaging finding. Neuroinfection was confirmed by lumber puncture and
CSF analysis. Other causes of seizure were identified based on neuroimaging.

 

 

 

Table 2: Age distribution of study population (years)

Age
distribution of study
population(years)

Years

?20

20(23.2%)

21-40

38(44%)

41-60

22(25.6)

?60

6(7%)

 

 

Table 3: Precipitants of seizure

Precipitants

Number of
patients

Sleep
deprivation

15(17.4%)

Alcohol

10(11.6%)

Emotional
stress

6(7%)

Hunger

5(5.8%)

Fatigue

4(4.6%)

Forty
(46.5%) patients reported having one or more precipitants for their seizure.
The precipitants in decreasing order were sleep deprivation, alcohol intake,
emotional stress, hunger and fatigue.

 

 

Table 4: Duration of seizure before first
starting medication

Duration of seizure before first starting
medication

Number of
patients

Less than 1
week

50(58%)

1 week to 1
month

15(17.4%)

1 month to
less than 6 months

6(7%)

More than 6
months to less than 1 year

10(11.6%)

More than 1
year

5(5.8%)

 

 

 

 

Table 5: Neuroimaging finding in patients with first
seizure

Neuroimaging
finding

Number of
patients

Normal

40(46.5%)

Neurocysticercosis
and calcified granuloma

25(29%)

stroke

14(16.3%)

Neuroinfection

2(2.3%)

Brain tumor

3(3.5%)

Cerebral atrophy

1(1.1%)

Others      

1(1.1%)

 

 

DISCUSSION

 

In our study we find
risk for recurrence following a 1st seizure to be 24.4% at 3 years.
Earlier studies have reported seizure recurrence following 1st seizure from 31% to 71% 13-19.
Such variation may be due to difference in basic study design,
characteristics of populations studied, mean duration of follow-up, and methods
of statistical analysis.

 

 

In our study causal factor for seizure could be
identified in 46.5% of patients based on neuroimaging and cerebrospinal fluid
analysis. Recurrence of seizure was found to be 60% in those patients with
identified causes. This was much higher than the patients with idiopathic

seizure with recurrence risk of 20% over the study
period of 3 years. Our
study showed slightly different percentage for causal factors of seizure than
the study done by Rajbhandari in Nepal.20 our study was done in
patients with first seizure unlike the former study which was done in patients
with first and recurrent seizure. Both the studies however found
neurocystercosis to be the most common identifiable cause of seizure in
Nepalese population. The presence of abnormal neuroimaging was not
significantly associated with seizure recurrence.

 

 

In the present study electroencephalography was done
in all patients presenting with first seizure. An abnormal EEG predicts seizure
recurrence, although there has not been agreement on the nature of the EEG
abnormality. In our study a generalized sharp wave pattern, a focal abnormality
on EEG and an abnormal EEG was associated with an increased recurrence risk.

 

In our study
anticonvulsants were prescribed to those patients whose risk of recurrence was
assumed to be high. This included patients with abnormal neuroimaging finding, family
history of epilepsy in first degree relative, abnormal physical examination and
abnormal EEG finding. Recurrence risk of seizure did not differ significantly
between those who were prescribed antiepileptic and those who were not.

 

 

 

Eighteen
(21%) patients reported having a family history of epilepsy in first degree
relative. Those patients with family history of epilepsy in their first degree
relative had higher rate of recurrence of seizure than those who did not have a
family history of seizure.

 

 

 

 

 

 

 

 

 

 

CONCLUSION

Epilepsy is a common problem in the general population. Most of
the patients with first seizure had identifiable cause. Recurrence of seizure
was observed in almost a quarter of patients within the study period of three
years.

 

 

RECOMMENDATION

Our study identifies
common causes of seizure like neurocysticercosis in our country. This is
preventable if attention is given to hygiene and sanitation. This study can be
applied as a basis by the policy makers in the process of reducing the prevalence
of seizure .

 

 

LIMITATION OF THE STUDY

Data was collected
from Nobel medical college, Biratnagar, which is a tertiary care centre. Thus,
this study may not reflect exact epidemiology of the population.

 

 

 

ACKNOWLEDGEMENT

We would like to
acknowledge all of our patients and their family members who were eager to give
information about their illness.

 

 

 

CONFLICT OF INTEREST

None

 

 

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