| Poster | Poster Session 09 Program Schedule
02/16/2024
03:30 pm - 04:45 pm
Room: Majestic Complex (Posters 61-120)
Poster Session 09: Epilepsy | Oncology | MS | Infectious Disease
Final Abstract #102
Vitamin B12 deficiencies moderate the relationship between higher depressive symptoms and lower left hippocampal volumes in older adults
Zachary Salling, Georgia State University, Atlanta, United States
Allyson Box, Georgia State University, Atlanta, United States
Vonetta Dotson, Georgia State University, Atlanta, United States
Category: Aging
Keyword 1: depression
Keyword 2: hippocampus
Objective:
Volume of the hippocampus, an area associated with memory, is known to decline in late life. Additionally, the literature indicates that lower hippocampal volumes are associated with depression and vitamin B12 deficiencies. However, whether vitamin B12 deficiencies moderate the association between depression and hippocampal volumes in older adults remains largely unexplored. Therefore, we examined the associations of self-reported depressive symptoms, vitamin B12 deficiency, and their interaction with hippocampal volumes in late life.
Participants and Methods:
The sample included 57 dementia-free participants (aged 68-93 yrs, 78.68 ± 6.68 yrs, 68% white, 88% female) from the National Alzheimer's Coordinating Center (NACC) dataset, with 19 of them exhibiting a vitamin B12 deficiency and the other 38 randomly selected from the full NACC sample based on demographic matching to the B12 deficiency group. Depressive symptoms were assessed using the total score from the Geriatric Depression Scale, 15-item (GDS-15), and vitamin B12 deficiencies were self-reported. Left and right hippocampal volumes (in cm3) were quantified using automated procedures in FreeSurfer. Multiple linear regression analyses were conducted, with the GDS-15 total score, vitamin B12 deficiency, and their interaction predicting left and right hippocampal volumes. Total brain volume, sex, race, and age were controlled for in the analysis. Follow-up analyses incorporated separate regressions for participants with and without vitamin B12 deficiency to investigate significant interaction effects.
Results:
The interaction between GDS-15 total scores and vitamin B12 deficiencies was significant for the left hippocampus (R2 = 0.44; p = 0. 04), but not for the right hippocampus (R2 = 0.33 p > 0. 05). Follow-up analyses showed that higher GDS-15 scores were significantly associated with smaller volumes in the left hippocampus for participants with B12 deficiency (R2 = 0.66; p = 0.003), but not for participants without a vitamin B12 deficiency (R2 = 0.47; p > 0.05).
Conclusions:
The present findings are in line with the existing literature showing associations among vitamin B12 deficiencies, depression, and lower hippocampal volume. Results suggest vitamin B12 deficiency moderates the relationship between depressive symptoms and hippocampal volumes, such that people with vitamin B12 deficiency have a stronger relationship between higher depressive symptoms and hippocampal volumes than people without a deficiency. The left-lateralized hippocampal effect may be related to the deficits in episodic memory function that have been previously associated with depression and vitamin B12 deficiencies. Future studies with larger samples and longitudinal follow-up could explore the association of vitamin B12 deficiencies, depression, and episodic memory functioning in older adults to test this possibility. Given the link between hippocampal volume decline and subsequent cognitive impairment and dementia in older adults, findings from the current study highlight the importance of incorporating assessment and treatment of B12 deficiencies in older adults reporting depressive symptoms.
|
|---|
