Interaction between stress and the BDNF Val66Met polymorphism in depression: a systematic review and meta-analysis

• Published in: BMC medicine Vol. 12; p. 7
• Main Authors: Hosang, Georgina M, Shiles, Celia, Tansey, Katherine E, McGuffin, Peter, Uher, Rudolf
• Format: Journal Article
• Language: English
• Published: England BioMed Central 16-01-2014
• Subjects: Brain-Derived Neurotrophic Factor - genetics; Child abuse & neglect; Depression - diagnosis; Depression - genetics; Depression - psychology; Humans; Medical research; Meta-analysis; Methionine - genetics; Older people; Polymorphism, Genetic - genetics; Stress; Stress, Psychological - diagnosis; Stress, Psychological - genetics; Stress, Psychological - psychology; Studies; Valine - genetics
• ISSN: 1741-7015
• DOI: 10.1186/1741-7015-12-7

Major depression is a disabling psychiatric illness with complex origins. Life stress (childhood adversity and recent stressful events) is a robust risk factor for depression. The relationship between life stress and Val66Met polymorphism in the brain-derived neurotrophic factor (BDNF) gene has received much attention. The aim of the present work was to review and conduct a meta-analysis on the results from published studies examining this interaction.
A literature search was conducted using PsychINFO and PubMed databases until 22 November 2013. A total of 22 studies with a pooled total of 14,233 participants met the inclusion criteria, the results of which were combined and a meta-analysis performed using the Liptak-Stouffer z-score method.
The results suggest that the Met allele of BDNF Val66Met significantly moderates the relationship between life stress and depression (P = 0.03). When the studies were stratified by type of environmental stressor, the evidence was stronger for an interaction with stressful life events (P = 0.01) and weaker for interaction of BDNF Val66Met with childhood adversity (P = 0.051).
The interaction between BDNF and life stress in depression is stronger for stressful life events rather than childhood adversity. Methodological limitations of existing studies include poor measurement of life stress.