Another dualism: cognitive versus personality predictors of rumination in later life depression

Rumination, a predisposing and perpetuating feature of depression, has been linked to personality and cognition. However, little is known about their comparative influence on rumination. This study examined personality and cognitive variables as predictors of rumination in early-onset, later life depression (LLD) relative to healthy controls (HC).

Participants were 98 adults aged 55-79 divided into an HC group and LLD group (including active and remitted depression). Secondary analysis considered the subset of LLD with a current depressive episode to investigate effects in state-level depression. Personality predictors included the five domains assessed by the NEO-PI-R. Cognitive domains were executive functioning, attention, and global cognitive ability. Hierarchical linear regressions included predictors of rumination, with variable blocks composed of 1) demographic characteristics, 2) group (LLD vs HC), 3) cognitive/personality variables, and 4) interaction terms for variables with significant main effects. Secondary state depression analysis considered MADRS score in the second block and select predictors in the third block.

Group (LLD vs HC) significantly predicted rumination in the primary analysis and remained significant following inclusion of all cognitive and personality variables. Neuroticism, and less significantly perseveration on the WCST, also predicted rumination; while there was some indication that cognitive variables were associated with increased rumination in LLD, results overall did not reach significance. MADRS score significantly predicted rumination in the secondary analysis, though predictor variables did not moderate this association.

Results demonstrate that personality, namely neuroticism, is more predictive of rumination than cognition in older adults. Depression history, neuroticism, and to a lesser extent cognitive flexibility were associated with higher levels of rumination in LLD, while only depression symptom severity was predictive of rumination in state depression. Findings suggest personality is more related to rumination than cognition in LLD, though the relationship may be distinct for state and trait depression.