Schizoid personality types often lack the ability to assess the impact of their own actions in social situations.A person with SzPD may feel suffocated when their personal space is violated and take actions to avoid this feeling. People who have SzPD tend to be happiest when in relationships in which their partner places few emotional or intimate demands on them and does not expect phatic or social niceties. It is not necessarily people they want to avoid, but negative or positive emotional expectations, emotional intimacy and self-disclosure. Therefore, it is possible for individuals with SzPD to form relationships with others based on intellectual, physical, familial, occupational or recreational activities, as long as there is no need for emotional intimacy. Donald Winnicott explains this is because schizoid individuals "prefer to make relationships on their own terms and not in terms of the impulses of other people." Failing to attain that, they prefer isolation. In general, friendship among schizoids is usually limited to one person, often also schizoid, forming what has been called a union of two eccentrics; "within it – the ecstatic cult of personality, outside it – everything is sharply rejected and despised".Although there is the belief people with SzPD are complacent and unaware of their feelings, many recognize their differences from others.
A 2011 study on suicidal inpatients at a Moscow hospital found that schizoids were the least common patients, while those with cluster B personality disorders were the most common. Asperger syndrome
Several studies have reported an overlap or comorbidity with the autism spectrum disorder Asperger syndrome. Asperger syndrome had traditionally been called "schizoid disorder of childhood", and Eugen Bleuler coined both the terms "autism" and "schizoid" to describe withdrawal to an internal fantasy, against which any influence from outside becomes an intolerable disturbance. In a 2012 study of a sample of 54 young adults with Asperger syndrome, it was found that 26% of them also met criteria for SzPD, the highest comorbidity out of any personality disorder in the sample (the other comorbidities were 19% for obsessive–compulsive personality disorder, 13% for avoidant personality disorder and one female with schizotypal personality disorder). Additionally, twice as many men with Asperger syndrome met criteria for SzPD than women. While 41% of the whole sample were unemployed with no occupation, this rose to 62% for the Aspergers and SzPD comorbid group. Tantam suggested that Asperger syndrome may confer an increased risk of developing SzPD. A 2019 study found that 54% of a group of males aged 11 to 25 with Asperger syndrome showed significant SzPD traits, with 6% meeting full diagnostic criteria for SzPD, compared to 0% of a control.In the 2012 study, it was noted that the DSM may complicate diagnosis by requiring the exclusion of a pervasive developmental disorder (PDD) before establishing a diagnosis of SzPD.