Recent studies on Autism spectrum disorder, while focusing on adult subjects, stressed the presence of full-threshold and subthreshold autistic symptoms in clinical populations, also providing valuable insights on how neurodevelopmental alterations may increase the risk towards the development of other psychiatric conditions. The present review takes into account the most recurring topics in this literature, such as the research on autistic traits and ruminative thinking, collecting evidences on the effects of these elements in clinical presentations. In particular, while autistic traits and ruminative thinking seem to act as vulnerability factors towards the development of post-traumatic symptoms after life events, they could be considered the starting point of different kinds of psychopathological trajectories depending from the specific neurobiological asset and its interactions with environment. In order to rethink the literature within a coherent theoretical framework, the Adult Autism Subthreshold Model is then discussed.