What factors affect the recurrence of epilepsy?

Patient's question:

Epilepsy has been going on for years, and it's still unclear. Why does epilepsy relapse? Many people ask me, but I don't understand either.

Doctor's answer:

The Impact on Epilepsy Recurrence in First-Degree Relatives of Idiopathic Epilepsy
The prevalence rate of epilepsy in first-degree relatives of idiopathic epilepsy is 2%-6%, higher than that of the general population (0.5%-1%). Idiopathic epilepsy actually encompasses various diseases and syndromes with different genetic forms, involving one or multiple genes. For example, childhood absence epilepsy is autosomal dominant, while idiopathic infantile spasms are autosomal recessive. In most cases, the inherited predisposition only increases the risk of seizure recurrence, and its penetrance is also limited by age. For instance, in childhood absence epilepsy characterized by 3H2 spike-and-wave complexes on EEG, more than 40% of siblings exhibit the same abnormal EEG at the appropriate age (5-16 years), but only 1/4 of them experience clinical recurrence, suggesting the role of environmental factors. In first-degree relatives of symptomatic epilepsy patients, the epilepsy prevalence rate is 1.5%, which is also higher than the general population, indicating the genetic influence of epilepsy when the same condition occurs. Some causes of symptomatic epilepsy, such as febrile seizures and tuberous sclerosis, are themselves genetic disorders.
2. Environmental Factors
① Age: Age affects the incidence, recurrence type, etiology, and prognosis of epilepsy. The onset of epilepsy is most common before the age of 20, accounting for 60%-80%. In terms of age and etiology, epilepsy recurrence in the neonatal and infantile periods is often due to organic brain diseases, such as birth injuries, infections, and congenital brain abnormalities. Primary epilepsy typically begins to recur before the age of 20, with two peak ages: 6-10 years and 14-17 years. In young and adult populations, traumatic brain injury is a significant factor or cause, while intracranial tumors are more common in middle age, and cerebrovascular diseases dominate in the elderly. On the other hand, the process of brain development also influences the form of epilepsy recurrence. For example, childhood absence epilepsy often begins around the age of 6-7 and may transition to generalized tonic-clonic seizures after puberty. Similarly, infantile spasms typically start before the age of 1 and may later evolve into atypical absence seizures or generalized tonic-clonic seizures.
② Endocrine: In female patients, any type of seizure recurrence tends to increase during the menstrual period and ovulation period. Experimental evidence shows that seizures are most likely to occur during periods of declining estrogen and rapid progesterone decline. Some patients experience seizures only during the menstrual period, a condition known as menstrual epilepsy. A few patients may have seizures only in the early stages of pregnancy, a condition referred to as gestational epilepsy.
③ Sleep: Idiopathic tonic-clonic seizures and myoclonic seizures often occur after waking up in the morning, while infantile spasms typically recur upon waking or before sleep. Benign childhood central-temporal lobe epilepsy mostly recurs during sleep. Additionally, insufficient sleep often leads to recurrence.
④ Triggers: Besides insufficient sleep, fatigue, hunger, constipation, alcohol consumption, emotional excitement, as well as various transient metabolic disorders and allergic reactions, can trigger seizures in patients. Hyperventilation can provoke absence seizures, excessive fluid intake can trigger tonic-clonic seizures, and flashing lights can induce myoclonic seizures.