Autism Spectrum Disorder: An Update on the Pathophysiology and Management Strategies

Autism is a complex neurobehavioral and neurodevelopment disorder with impairments in sociability, language, repetitive, and restrictive stereotypical behaviour as the core symptoms. The term “autism” was first introduced in DSM-III in the year 1980; however, it was changed to autism spectrum disorder (ASD) in DSM-V. It starts in early childhood at the age of around 3 years and persists throughout life. According to data from the Centres for Disease Control and Prevention (CDC), USA, the prevalence of ASD has increased from 1 in 88 (2008 data) to 1 in 59 (2018 data). Being a complex neurological disorder, its etiology is not clear. However, numerous neurochemical pathways have been explicated that may be responsible for the development of this disorder. Besides, it has been evidenced that immune dysfunction and genetic predisposition have a major role in its progression. Some of the major neurochemical systems implicated to be involved in its etiology are glutaminergic and GABAergic as major and others such as DAergic system, adrenergic system, serotonergic system, and the endocannabinoid system. These above-mentioned pathways are crucial in the maturation and development of neurons in different parts of the brain, thus, alteration in any of these pathways enumerates a significant role in the progression of ASD. Current treatment options are antipsychotic medications, which only provide symptomatic relief for behavioral and psychiatric complications such as irritability, anxiety, mood fluctuations,etc.. These medications are not effective in treating the core symptoms of ASD. Given the lack of effective treatment options for ASD, drugs targeting the core pathology of the disorder are the need of the hour. Although numerous studies have discussed pharmacotherapy for ASD, the present chapter, more importantly, focuses on the available treatment options for ASD and updates on the recent research approaches for the prevention and treatment of ASD.