The impact of alcohol use on tuberculosis treatment outcomes: a systematic review and meta-analysis

Abstract

Alcohol use is associated with increased risk of developing tuberculosis (TB) disease, yet the impact of alcohol use on TB treatment outcomes has not been summarized. We aimed to quantitatively review evidence of the relationship between alcohol use and poor TB treatment outcomes. We conducted a systematic review of PubMed, EMBASE, and Web of Science (January 1980-May 2018). We categorized studies as having a high- or low-quality alcohol use definition and examined poor treatment outcomes individually and as two aggregated definitions (i.e., including or excluding loss to follow-up [LTFU]). We analyzed drug-susceptible (DS-) and multidrug-resistant (MDR-) TB studies separately. Our systematic review yielded 111 studies reporting alcohol use as a predictor of DS- and MDR-TB treatment outcomes. Alcohol use was associated with increased odds of poor treatment outcomes (i.e., death, treatment failure, and LTFU) in DS (OR 1.99, 95% CI 1.57-2.51) and MDR-TB studies (OR 2.00, 95% CI 1.73-2.32). This association persisted for aggregated poor treatment outcomes excluding LTFU, each individual poor outcome, and across sub-group and sensitivity analyses. Only 19% of studies used high-quality alcohol definitions. Alcohol use significantly increased the risk of poor treatment outcomes in both DS- and MDR-TB patients. This study highlights the need for improved assessment of alcohol use in TB outcomes research and potentially modified treatment guidelines for TB patients who consume alcohol.

Figure 1

PRISMA flow chart of studies included in the meta-analysis. *Japanese (n = 21), German (n = 8), Polish (n = 5), and Hungarian (n = 1). ^†Three citations were split due to reporting on two unique cohorts, therefore were treated as two studies each. ^‡List not mutually exclusive as many studies report more than one outcome. ^§Death or treatment failure. TB = tuberculosis; LTBI = latent tuberculosis infection; WHO = World Health Organization; LTFU = loss to follow-up; PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

Figure 2

A) Forest plots of the association between alcohol use and Poor Outcome A (i.e., death, failure, and LTFU) for both DS-TB and MDR-TB studies and the breakdown of participants with poor outcome by exposure group. B) Forest plots of the association between alcohol use and Poor Outcome B (i.e., death and failure) for both DS-TB and MDR-TB studies and the breakdown of participants with poor outcome by exposure group. Squares indicate ORs from individual studies; square size reflects the statistical weight of the study. Horizontal lines indicate 95% CIs. Diamonds represent the combined ORs and 95% CIs. The vertical solid line shows no effect (OR = 1). The P values are from tests that the combined ORs equal 1. OR = odds ratio; CI = confidence interval; DS-TB = drug-susceptible tuberculosis; MDR-TB = multidrug-resistant TB; LTFU = loss to follow-up.

Figure 2

A) Forest plots of the association between alcohol use and Poor Outcome A (i.e., death, failure, and LTFU) for both DS-TB and MDR-TB studies and the breakdown of participants with poor outcome by exposure group. B) Forest plots of the association between alcohol use and Poor Outcome B (i.e., death and failure) for both DS-TB and MDR-TB studies and the breakdown of participants with poor outcome by exposure group. Squares indicate ORs from individual studies; square size reflects the statistical weight of the study. Horizontal lines indicate 95% CIs. Diamonds represent the combined ORs and 95% CIs. The vertical solid line shows no effect (OR = 1). The P values are from tests that the combined ORs equal 1. OR = odds ratio; CI = confidence interval; DS-TB = drug-susceptible tuberculosis; MDR-TB = multidrug-resistant TB; LTFU = loss to follow-up.