White matter fiber microstructure is associated with prior hospitalizations rather than acute symptomatology in major
Susanne Meinert1, Elisabeth J Leehr1, Dominik Grotegerd1
1Department of Psychiatry, University of Münster, Münster, Germany.
Background:
Eighty percent of all patients suffering from major depressive disorder (MDD) relapse at least once in their lifetime. Thus, understanding the neurobiological underpinnings of the course of MDD is of utmost importance. A detrimental course of illness in MDD was most consistently associated with superior longitudinal fasciculus (SLF) fiber integrity. As similar associations were, however, found between SLF fiber integrity and acute symptomatology, this study attempts to disentangle associations attributed to current depression from long-term course of illness.
Methods:
A total of 531 patients suffering from acute (N = 250) or remitted (N = 281) MDD from the FOR2107-cohort were analyzed in this cross-sectional study using tract-based spatial statistics for diffusion tensor imaging. First, the effects of disease state (acute v. remitted), current symptom severity (BDI-score) and course of illness (number of hospitalizations) on fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity were analyzed separately. Second, disease state and BDI-scores were analyzed in conjunction with the number of hospitalizations to disentangle their effects.
Results:
Disease state (pFWE < 0.042) and number of hospitalizations (pFWE< 0.032) were associated with decreased FA and increased MD and RD in the bilateral SLF. A trend was found for the BDI-score (pFWE > 0.067). When analyzed simultaneously only the effect of course of illness remained significant (pFWE < 0.040) mapping to the right SLF.
Conclusions:
Decreased FA and increased MD and RD values in the SLF are associated with more hospitalizations when controlling for current psychopathology. SLF fiber integrity could reflect cumulative illness burden at a neurobiological level and should be targeted in future longitudinal analyses.
Insights
Major depressive disorder (MDD) relapse is common. This study found that reduced integrity of the superior longitudinal fasciculus (SLF) is linked to a worse illness course, not just current symptoms.
Area of Science:
- Neuroscience
- Psychiatry
- Medical Imaging
Background:
- Major Depressive Disorder (MDD) has a high lifetime relapse rate, necessitating understanding its neurobiological basis.
- The superior longitudinal fasciculus (SLF) has been implicated in MDD, but its association with illness course versus acute symptoms is unclear.
Purpose of the Study:
- To investigate the neurobiological underpinnings of Major Depressive Disorder (MDD) course.
- To differentiate the effects of current depression severity from the long-term illness trajectory on SLF integrity.
Main Methods:
- Cross-sectional study of 531 patients with acute or remitted MDD.
- Diffusion tensor imaging (DTI) and tract-based spatial statistics (TBSS) were used to analyze SLF integrity.
- Statistical analyses examined the impact of disease state, symptom severity (BDI-score), and hospitalization history on DTI metrics (FA, MD, RD).
Main Results:
- Both disease state and hospitalization history were associated with decreased fractional anisotropy (FA) and increased mean diffusivity (MD) and radial diffusivity (RD) in the bilateral SLF.
- When analyzed together, only the number of hospitalizations remained a significant predictor of altered SLF integrity, specifically in the right SLF.
- Current symptom severity (BDI-score) showed a trend towards association but did not reach statistical significance.
Conclusions:
- Reduced SLF fiber integrity, indicated by decreased FA and increased MD/RD, is associated with a history of more hospitalizations in MDD patients, independent of current symptom severity.
- SLF integrity may serve as a neurobiological marker for cumulative illness burden in MDD.
- Future longitudinal studies should examine SLF integrity to better understand the progression of MDD.
More Related Videos
Related Concept Videos
01:27Depressive Disorders: MDD and Dysthymia
01:27Depressive Disorders: Etiology
Biological Factors in Depression
Biological predispositions significantly influence the risk of developing depressive disorders. Genetic studies highlight the role of variations in the serotonin transporter...