Background: Studies of risk factors for suicidal behavior are typically restricted to narrow age ranges, making it difficult to determine if they have the same relevance or potency across the full adult lifespan.
Methods: This study examined selected clinical and neurocognitive risk factors for suicidal behavior – borderline personality traits, aggression, depressive rumination, memory performance, and language fluency– in a multi-site sample (N = 309, ages 16–80) of depressed patients with a recent (last 5 years) suicide attempt or no history of attempt, and demographically similar non-psychiatric controls. We examined cross-sectional age and attempter/non-attempter differences on these risk factors, and whether certain risk factors were more prominent discriminators of past suicide attempt earlier or later in the lifespan. Correlations with age were computed, and logistic regression was used to classify attempter status based on each risk factor and its interaction with age.
Results: Nearly all risk factors were negatively correlated with age. Borderline traits, aggression, memory, and category fluency each predicted attempter status (p < 0.05), but these effects were not different across ages. In contrast, the association between rumination and suicide attempt status differed across the lifespan, becoming a stronger discriminator of past suicidal behavior at older ages.
Limitations: The cross-sectional design limits our developmental findings.
Conclusions: Despite age-related changes in symptom severity or neurocognitive performance, key risk factors for suicidal behavior previously identified in studies with more restricted age-ranges are salient throughout the adult lifespan. In contrast, depressive rumination may be particularly salient in later life.