How personality functioning shapes symptom development during and after treatment: A random intercept cross lagged...

Area of Science:

• Psychology
• Psychiatry
• Longitudinal Studies

Background:

• Understanding the long-term impact of personality functioning (PF) on mental and physical health is crucial for effective psychotherapy.
• Previous research has focused on between-person differences, but within-person fluctuations require further investigation.

Purpose of the Study:

• To investigate the long-term influence of within-person fluctuations in personality functioning (PF) on mental and physical symptoms in patients undergoing psychotherapy.
• To examine the longitudinal effects between PF and symptoms of depression, anxiety, and somatic distress.

Main Methods:

• Reanalysis of observational data from 2094 participants in the Multicenter Effectiveness Study of Inpatient Psychosomatic Psychotherapeutic Treatment (MEPP).
• Utilized a Random Intercept-Cross Lagged Panel Model (RI-CLPM) to assess within-person longitudinal effects.
• Controlled for demographic variables (age, sex) and treatment characteristics (condition, length).

Main Results:

• Significant between-person intercorrelations were found among all measured constructs.
• Personality functioning (PF) at hospital discharge predicted somatic symptom load, depressive symptoms, anxiety, and PF itself at follow-up.
• Depressive symptoms at baseline influenced general symptom burden and PF development during treatment, and strongly affected anxiety and somatic symptoms at follow-up.

Conclusions:

• Intraindividual deviations in personality functioning (PF) have a sustained impact on symptom development post-psychotherapy.
• Depressive symptoms play a significant role in psychotherapy outcomes, influencing both symptom burden and personality functioning.