A meta-analysis of acute use of alcohol and the risk of suicide attempt

Abstract

Background: No review has used a meta-analytic approach to estimate common odds ratios (ORs) for the effect of acute use of alcohol (AUA) on suicide attempts. We aim to report the results of the first meta-analysis of controlled epidemiological studies on AUA and suicide attempt.

Method: The English-language literature on Medline, PsycINFO and Google Scholar was searched for original articles and critical review on AUA and suicide attempt (period 1996-2015). Studies had to report an OR estimate for this association. Common ORs and 95% confidence intervals (CIs) from random effects in meta-analyses for any AUA and two levels of alcohol use on suicide attempt were calculated.

Results: In all, seven studies provided OR estimates for the likelihood of suicide attempt by AUA, compared with those who did not drink alcohol. Studies used case-control (n 3) and case-crossover designs (n 4). Meta-analysis revealed a common OR of 6.97 (95% CI 4.77-10.17) for any AUA. Using four studies, 'low levels of acute drinking' resulted in an OR of 2.71 (95% CI 1.56-4.71) and 'high levels' had an OR of 37.18 (95% CI 17.38-79.53).

Conclusions: AUA is associated with increased likelihood of a suicide attempt, particularly at high doses. Such data should be incorporated into estimates of the burden of disease associated with alcohol use, which are currently limited by a consideration of only alcohol's chronic effects. Future research should focus on the mechanisms through which AUA confers risk for attempt.

Keywords: Acute alcohol use; case–control studies; case–crossover studies; meta-analyses; suicide attempt.

Figure 1

Forest plot showing effect sizes for suicide attempt according to any acute alcohol use in individual studies Heterogeneity Q = 9.32 (5 df); p = 0.097 Egger's test for small-study effects p = 0.251 Ca-XO: Case-Crossover, CaCo:Case-Control, fem:Female, BAC: Blood Alcohol Concentration Hou: Houston, Phila: Philadelphia, MS: Mississippi 2004 Multisite (4 countries): US, CA, MX & AU 2016 Multisite (17 countries): AR, BY, BR, CA, CN, CR, DO, GT, GY, IN, IE, KR, MX, NI, PA, SE & TW

Figure 2

Forest plot showing effect sizes for suicide attempt according to 'low acute alcohol use' in individual studies Heterogeneity Q = 2.4 (3 df); p = 0.494 Egger's test for small-study effects p = 0.251 Ca-XO: Case-Crossover, CaCo:Case-Control, fem:Female, BAC: Blood Alcohol Concentration Phila: Philadelphia, MS: Mississippi 2016 Multisite (17 countries): AR, BY, BR, CA, CN, CR, DO, GT, GY, IN, IE, KR, MX, NI, PA, SE & TW

Figure 3

Forest plot showing effect sizes for suicide attempt according to 'heavy acute alcohol use' in individual studies Heterogeneity Q = 2.02 (3 df); p = 0.567 Egger's test for small-study effects p = 0.879 Ca-XO: Case-Crossover, CaCo:Case-Control, fem:Female, BAC: Blood Alcohol Concentration Phila: Philadelphia, MS: Mississippi 2016 Multisite (17 countries): AR, BY, BR, CA, CN, CR, DO, GT, GY, IN, IE, KR, MX, NI, PA, SE & TW