Suicide Risk across Latent Class Subgroups: A Test of the Generalizability of the Interpersonal Psychological Theory of Suicide

It remains unclear whether the Interpersonal Psychological Theory of
Suicide (IPTS; Joiner, 2005) is generalizable to the population or holds more
explanatory power for certain subgroups compared to others. The aim of this
study was to (1) identify subgroups of individuals who endorsed suicide ideation
in the past month based on a range of mental health and demographic variables,
(2) compare levels of the IPTS constructs within these subgroups, and (3) test
the IPTS predictions for suicide ideation and suicide attempt for each group.
Latent class, negative binomial, linear, and logistic regression analyses were
conducted on population-based data obtained from 1,321 adults recruited from
Facebook. Among participants reporting suicide ideation, four distinct patterns
of risk factors emerged based on age and severity of mental health symptoms.
Groups with highly elevated mental health symptoms reported the highest
levels of thwarted belongingness and perceived burdensomeness. Tests of the
IPTS interactions provided partial support for the theory, primarily in young
adults with elevated mental health symptoms. Lack of support found for the
IPTS predictions across the subgroups and full sample in this study raise some
questions around the broad applicability of the theory.