For a study, the researchers investigated the potential association between autism spectrum disorder and hydrocephalus in a large population-based cohort. The cohort consisted of 86,571 individuals, of which 14,654 were diagnosed with autism spectrum disorder, 28,606 were population controls, and the remaining were diagnosed with other psychiatric disorders. Researchers identified 201 hydrocephalus cases, 68 among autism spectrum disorder patients and 40 among authorities (OR3.77, 95% CI2.48–5.78), which corresponds to an absolute risk of 0.46% (i.e., approximately one in 217 children with autism spectrum disorder had co-occurring hydrocephalus). The autism spectrum disorder-hydrocephalus relation was significant over the entire subgroup spectrum of autism spectrum disorder. Given the considerable risk of hydrocephalus among patients with autism spectrum disorder, researchers suggested that patients with autism spectrum disorder should be examined for co-occurring hydrocephalus on a routine basis as timely neurosurgical intervention was essential. Likewise, attention must be paid to traits of autism spectrum disorder in children with hydrocephalus. The outlines called for future investigations on a potentially shared etiology between hydrocephalus and autism spectrum disorder, including the role of abnormal CSF dynamics in the pathogenesis of autism spectrum disorder.