Subject: A retrospective cross-sectional, observational survey study to analyse role of sodium valproate in the treatment of epilepsy.

Epilepsy is a neurological disorder that is characterized by an enduring predisposition to generate epileptic seizures and the associated cognitive, psychological and social consequences.¹

Epilepsy is the third leading contributor to the global burden of disease for neurological disorders the global burden of disease for neurological disorders and affects 65 million people worldwide.^{2, 3} According meta-analysis of international studies, the prevalence of meta-analysis of international studies, the prevalence of epilepsy is 6.4 cases per 1,000 persons and the annual incidence is 67.8 cases per 100,000 person-years.⁴

It is estimated that there are more than 10 million persons with epilepsy (PWE) in India.⁵ Its prevalence is about 1% in our population. The prevalence is higher in the rural (1.9%) compared to urban population (0.6%).^{6, 7}

Seizures occur when there is abnormal synchronous neuronal firing in a section of the brain, or throughout the entirety of the brain, when networks are irregularly formed or are perturbed by a structural, infectious, or metabolic disturbance. In children, the most common causes of seizures are genetic, injury due to perinatal insults, and malformations of cortical development.⁸ In adults without a genetic predisposition to epilepsy, common aetiologies for seizures include encephalitis/meningitis, traumatic brain injury, and brain tumours.⁹ In elderly patients, epilepsy is usually the result of primary neurodegenerative disorders, head trauma, and brain tumours.^{10, 11}

Epilepsy can persist for years and often for the patient's lifetime. ASDs (Anti-seizure drug) are the primary therapy for epilepsy and are symptomatic treatments that control seizures.¹² The choice of ASDs varies with different seizure types and epileptic syndromes.¹³ About 30 ASDs are currently used, of which most were approved over the last 30 years.¹³

Sodium valproate is an anticonvulsant. There is substantial evidence that Valproic acid increases γ- aminobutyric acid (GABA) synthesis and release and potentiates by these mechanisms GABAergic transmission in specific brain regions. Valproic acid has also been found to reduce the release of the excitatory amino acid β-hydroxybutyric acid and to attenuate neuronal excitation mediated by activation of N-methyl-D-aspartate (NMDA) glutamate receptors. In addition to these effects, valproic acid exerts direct actions on excitable membranes, including blockade of voltage-dependent sodium channels.¹⁴

A prospective randomized comparative study conducted during the period from April 2014 to March 2015, on adult patients suffering from idiopathic generalized tonic-clonic seizure (GTCS) showed Valproic acid is more effective than lamotrigine as first-line drug in the treatment of adults with newly diagnosed idiopathic generalized tonic-clonic seizures. After three months of treatment, 53.33% patients taking Valproic acid and 26.67% patients taking lamotrigine group were seizure-free. At six months, seizure freedom was observed in 63.33% patients taking Valproic acid and 46.67% patients taking lamotrigine. At the last observation after 12 months follow up, 76.67% patients taking Valproic acid and 56.67% patients taking lamotrigine were seizure-free. This difference was statistically significant (p < 0.03).¹⁵