The quote titling this post - "specific clinical and neuropsychological dimensions might be related to suicidal behaviors in ASD [autism spectrum disorder]" - comes from the findings reported by Luisa Weiner and colleagues  (open-access). It adds to other recent research talking about how elements of autism *might* associate with suicidality (see here). I should warn you that some of the Weiner findings make for difficult reading.
Authors described a case report of "a 21-year-old male [Mr A] with ASD who attempted suicide twice, in the absence of other psychiatric diagnoses." They detail how, following some quite comprehensive observations, a possible *connection* was noted between his suicidality and "some of the core clinical and neuropsychological features of ASD."
A few important points are highlighted in the Weiner study: "Mr. A. reported that his suicidal thoughts started when he was 18, following an unrequited infatuation with a classmate – the result of a rational decision: he had decided to “fall in love” with her." Things did not however go as he planned, as we are told that: "He started having “obsessive negative thoughts”, and attempted suicide by jumping from a window." He survived but "his suicidal thoughts lingered, characterized by a restrictive, rigid pattern."
Researchers relied on the Beck Depression Inventory (BDI) to rule out depression in this case: his score "was in the normal range (3/63)." This inventory is one of a few that have been described as being "robust in their measurement properties in the general population"  but with perhaps more to do in the context of its use in autism. In the absence of depression or rather elevated self-report scores indicative of depression, authors suggest this raises "the question of whether the persistence of suicidal thoughts was associated with ASD-related features."
The Weiner findings have to be placed in the context of other independent research looking at suicidality and autism. First, risk of suicidality is seemingly heightened when autism is diagnosed (see here). Second, although depression - an important variable *linked* to suicidality - is over-represented in relation to autism (see here), questions are still being asked about the impact of depression in relation to suicidality accompanying autism in the context of an often complicated clinical picture (see here). Third, the idea that the features/traits of autism might themselves be independent predictors of suicidality in autism has been discussed on several research occasions (see here and see here and see here).
The culmination of all this work is that quite a lot more research and clinical resources need to be ploughed into looking at suicidality and autism. And, importantly, translating said research into real-world actions to potentially save lives.
If you need someone to talk to, there are organisations out there...
 Weiner L. et al. A case study of suicidality presenting as a restricted interest in autism Spectrum disorder. BMC Psychiatry. 2019; 19: 126.
 Cassidy SA. et al. Measurement properties of tools used to assess depression in adults with and without autism spectrum conditions: A systematic review. Autism Res. 2018 May;11(5):738-754.