Seizures & Other Possible Connections
Age
Asthma
Congestive Heart Failure
Depression
Embolic Conditions
Gender
Hypertension
Illicit Drugs
Immunization
Race
Age
Although young children are at risk of experiencing seizures, the risk in adults increases as we age. It is not known if this is because of aging itself, or because of the accumulated effects of a lifetime of repeated exposure to the various toxins in our environments.
Asthma
Although one study suggests that a history of asthma may increase the risk for epilepsy, conclusive evidence of increased prevalence of epilepsy among those with asthma has not been found.
However, many studies have shown that chronic administration of certain drugs used for treating asthma, especially when used in combination with other drugs, may cause many complications, including status epilepticus.
[1]
Theophylline is one such drug that has come up in medical reports relatively often. This drug is commonly used to treat chronic asthma. It has a very low therapeutic index, which increases its likelihood of toxicity. Various studies have shown that large doses of theophylline administered to patients can induce status epilepticus. For instance, one study at Children's Memorial Hospital has found that a low percentage of children have seizures when large doses of theophylline are in their blood stream.
[2] Most of these children are previously neurologically normal.
1. Status Epilepticus in an Asthmatic Child. Casha, P. et al., Arch Pediatr. 1994. (9):816-818.
2. Theophylline Toxicity in Children: A Retrospective View. Powell, EC. et al., Pediatr Emerg Care. 1993. (3):129-133.
Congestive Heart Failure
Although congestive heart failure does not cause epilepsy, it may "predict" it (by being a "marker" for other cardiac factors possibly linked to seizures).
Depression
Some studies suggest an association between depression and an increased risk for epilepsy. Some treatments for depression have also been associated with an increased risk for epilepsy. Some anti-seizure medications may alter the mood, precipitating depression. Many people living with epilepsy (up to 20%) also experience depression; their interactive effects are not really known.
No increase in risk for epilepsy has been suggested or identified for other major psychiatric disorders.
Embolic Conditions
Two case studies have suggested a possible association between cardiac embolic stroke risk factors (valvular disease, atrial fibrillations, myocardial infarction) with a 2- to 3-fold increase in risk for epilepsy. More study is needed.
Gender
Population-based studies show the incidence of unprovoked seizures and epilepsy to be higher in males than in females. (This is after accounting for added risk factors, such as head injury, stroke or CNS infections, all of which occur more frequently in males.) While, these gender-based differences are not statistically significant, they may provide clues for future research.
Hypertension
Some studies suggest that hypertension (high blood pressure) may be associated with an increased risk for epilepsy. Other studies suggest that this may be the case only if there is left ventricular hypertrophy (increase in the size of constituent cells). However, more study is needed.
Illicit Drugs
Many illicit drugs, especially heroin, are with an increased risk for epilepsy. Cannabis (marijuana) may be protective (lower the risk of epilepsy) for some types of seizures.
Immunization
There has been considerable controversy about immunization and the risk of encephalopathy (any degenerative disease of the brain) leading to the development of epilepsy. Encephalopathies have been reported for virtually all vaccines; the vaccine for pertussis (whooping cough) has been linked to some severe childhood epileptic syndromes. Yet cutting back on its use led to an epidemic of pertussis in Britain in the late 1970s.
Studies show that there is a very slight increased risk (between 1 in 100,000 and 1 in 300,000 vaccinations) for an acute neurologic syndrome occurring within 1 week of immunization, but that after 1 year, none had any recognizable syndrome and developed epilepsy. Other problems could be attributed to other clinical explanations.
Other studies show an increased risk for a febrile seizure within 1 month of immunization. Many vaccines (including that for pertussis) are "pyrogens", causing a low-grade fever in many children receiving them. This fever may trigger a febrile seizure in susceptible children.
Although there is a small risk, the risks associated with the childhood diseases being vaccinated against are far greater.
Race
Studies do not show any evidence of different risk factors which cannot be attributed to socioeconomic and environmental factors.
