Fluctuating emotions, fluctuating risk? Evidence from a high-frequency EMA study of affective dynamics and suicidal...

Affect plays an important role in suicidal ideation (SI), yet little is known about how affective dynamics relate to momentary and between-person differences in SI. This study is the first to systematically examine multiple indices of affective dynamics in relation to passive and active SI, using high-frequency ecological momentary assessment (EMA) in a high-risk clinical sample.

Seventy-four psychiatric inpatients diagnosed with major depressive disorder completed six days of EMA with ten prompts per day measuring positive affect (PA), negative affect (NA), and passive and active SI. Within- and between-person associations of affective intensity and affective dynamics, including variability, instability, acute changes, and inertia, in relation to SI were examined.

Momentary increases in PA were associated with lower, whereas increases in NA were associated with higher passive and active SI, even after controlling for SI at the previous assessment. Moment-to-moment instability in PA showed concurrent associations with lower SI, but these effects were attenuated after accounting for prior SI. No within-person associations were observed for NA instability or acute changes in affect. At the between-person level, higher average levels, greater variability, and higher inertia of PA were associated with lower overall SI, whereas higher average NA was associated with greater SI. Dynamic indices of NA were not associated with SI.

Affective intensity showed the most robust associations with SI at both analytical levels. Dynamic features of PA, particularly between persons, may contribute to differentiating SI severity in high-risk inpatients with depression, with relevant clinical implications discussed.