Serum brain-derived neurotrophic factor level is reduced in antidepressant-free patients with late-life depression

Abstract

Objectives. The aim of the present study is to investigate serum BDNF levels in older depressed patients as compared to healthy elderly controls. Methods. Twenty-nine elderly subjects with major depression and 42 healthy older adults were enrolled to this study. All depressed patients were antidepressant-free for at least 1 month prior clinical and laboratorial assessments. Serum BDNF levels were determined by sandwich ELISA. Results. BDNF levels were lower in elderly depressed patients as compared to controls (P=0.034). Patients with late-onset depression had the lowest BDNF level (median 478.5, interquartile range 373.5–740.9 pg/l) when compared to early-onset depression (median 620.7, interquartile range 366.1–971.9 pg/l) and healthy controls (median 711.3, interquartile range 534.7–1181.0 pg/l) (P<0.03). Conclusions. Reduced serum BDNF level may be a state marker of late-life depression in non-medicated elderly patients. Our findings provide further evidences that reduced neurotrophic support may have an important role in the physiopathology of late-life depression.

Key words::

• Brain-derived neurotrophic factor
• geriatric depression
• late-onset depression
• physiopathology
• cognition

Acknowledgements

This work was funded by grants from Rede Instituto Brasileiro de Neurociência (IBN Net/Finep), Funda-Ção de Amparo à Pesquisa do Estado de São Paulo (FAPESP, grant no. 02/12633-7), AssociaÇão Beneficente Alzira Denise Hertzog da Silva (ABADHS). The funding sources had no further role in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication.

Statement of interest

None to declare.