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Association between BDNF levels and suicidal behaviour: a systematic review and meta-analysis.

Eisen RB, Perera S, Banfield L, Anglin R, Minuzzi L, Samaan Z - Syst Rev (2015)

Bottom Line: The qualitative review of the literature did not provide consistent support for an association between BDNF levels and suicidal behaviour.The evidence has significant methodological limitations.PROSPERO CRD42015015871.

View Article: PubMed Central - PubMed

Affiliation: MiNDS Neuroscience Graduate Program, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L8, Canada. eisenrb@mcmaster.ca.

ABSTRACT

Background: Suicidal behaviour is a complex phenomenon with a multitude of risk factors. Brain-derived neurotrophic factor (BDNF), a protein crucial to nervous system function, may be involved in suicide risk. The objective of this systematic review is to evaluate and summarize the literature examining the relationship between BDNF levels and suicidal behaviour.

Methods: A predefined search strategy was used to search MEDLINE, EMBASE, PsychINFO, and CINAHL from inception to December 2015. Studies were included if they investigated the association between BDNF levels and suicidal behaviours (including completed suicide, attempted suicide, or suicidal ideation) by comparing BDNF levels in groups with and without suicidal behaviour. Only the following observational studies were included: case-control and cohort studies. Both clinical- and community-based samples were included. Screening, data extraction, and risk of bias assessment were conducted in duplicate.

Results: Six-hundred thirty-one articles were screened, and 14 were included in the review. Three studies that assessed serum BDNF levels in individuals with suicide attempts and controls were combined in a meta-analysis that showed no significant association between serum BDNF and suicide attempts. The remaining 11 studies were not eligible for the meta-analysis and provided inconsistent findings regarding associations between BDNF and suicidal behaviour.

Conclusions: The findings of the meta-analysis indicate that there is no significant association between serum BDNF and attempted suicide. The qualitative review of the literature did not provide consistent support for an association between BDNF levels and suicidal behaviour. The evidence has significant methodological limitations.

Systematic review registration: PROSPERO CRD42015015871.

No MeSH data available.


Related in: MedlinePlus

Serum BDNF in attempted suicide. Legend: Forest plot representing the differences in serum BDNF level between individuals with suicide attempts and psychiatric controls
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Fig2: Serum BDNF in attempted suicide. Legend: Forest plot representing the differences in serum BDNF level between individuals with suicide attempts and psychiatric controls

Mentions: A meta-analysis was performed using the results of three case-control studies that compared serum BDNF levels between suicide attempters and psychiatric controls [29, 34, 43] (Figure 2). These studies were selected for inclusion in the meta-analysis based on their similar study designs (all case-control studies), definitions of suicidal behaviour (attempted suicide), and comparison groups (psychiatric controls). A random-effects model was used. The pooled estimate revealed a standardized mean difference (SMD) of −0.32 (95 % CI −1.01 to 0.37), which corresponds to a small effect size according to Cohen’s criteria [44]. However, this estimate was not significant (p = 0.36) and was associated with substantial heterogeneity (I2 = 73 %, p = 0.02).


Association between BDNF levels and suicidal behaviour: a systematic review and meta-analysis.

Eisen RB, Perera S, Banfield L, Anglin R, Minuzzi L, Samaan Z - Syst Rev (2015)

Serum BDNF in attempted suicide. Legend: Forest plot representing the differences in serum BDNF level between individuals with suicide attempts and psychiatric controls
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4697315&req=5

Fig2: Serum BDNF in attempted suicide. Legend: Forest plot representing the differences in serum BDNF level between individuals with suicide attempts and psychiatric controls
Mentions: A meta-analysis was performed using the results of three case-control studies that compared serum BDNF levels between suicide attempters and psychiatric controls [29, 34, 43] (Figure 2). These studies were selected for inclusion in the meta-analysis based on their similar study designs (all case-control studies), definitions of suicidal behaviour (attempted suicide), and comparison groups (psychiatric controls). A random-effects model was used. The pooled estimate revealed a standardized mean difference (SMD) of −0.32 (95 % CI −1.01 to 0.37), which corresponds to a small effect size according to Cohen’s criteria [44]. However, this estimate was not significant (p = 0.36) and was associated with substantial heterogeneity (I2 = 73 %, p = 0.02).

Bottom Line: The qualitative review of the literature did not provide consistent support for an association between BDNF levels and suicidal behaviour.The evidence has significant methodological limitations.PROSPERO CRD42015015871.

View Article: PubMed Central - PubMed

Affiliation: MiNDS Neuroscience Graduate Program, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L8, Canada. eisenrb@mcmaster.ca.

ABSTRACT

Background: Suicidal behaviour is a complex phenomenon with a multitude of risk factors. Brain-derived neurotrophic factor (BDNF), a protein crucial to nervous system function, may be involved in suicide risk. The objective of this systematic review is to evaluate and summarize the literature examining the relationship between BDNF levels and suicidal behaviour.

Methods: A predefined search strategy was used to search MEDLINE, EMBASE, PsychINFO, and CINAHL from inception to December 2015. Studies were included if they investigated the association between BDNF levels and suicidal behaviours (including completed suicide, attempted suicide, or suicidal ideation) by comparing BDNF levels in groups with and without suicidal behaviour. Only the following observational studies were included: case-control and cohort studies. Both clinical- and community-based samples were included. Screening, data extraction, and risk of bias assessment were conducted in duplicate.

Results: Six-hundred thirty-one articles were screened, and 14 were included in the review. Three studies that assessed serum BDNF levels in individuals with suicide attempts and controls were combined in a meta-analysis that showed no significant association between serum BDNF and suicide attempts. The remaining 11 studies were not eligible for the meta-analysis and provided inconsistent findings regarding associations between BDNF and suicidal behaviour.

Conclusions: The findings of the meta-analysis indicate that there is no significant association between serum BDNF and attempted suicide. The qualitative review of the literature did not provide consistent support for an association between BDNF levels and suicidal behaviour. The evidence has significant methodological limitations.

Systematic review registration: PROSPERO CRD42015015871.

No MeSH data available.


Related in: MedlinePlus